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Texture Rendering (#9)

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Co-authored-by: Zachary Levy <zachary@sunforge.is>
Reviewed-on: #9
This commit was merged in pull request #9.
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Zachary Levy
2026-04-22 00:05:08 +00:00
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@@ -47,68 +47,107 @@ primitives and effects can be added to the library without architectural changes
### Overview: three pipelines
The 2D renderer will use three GPU pipelines, split by **register pressure compatibility** and
**render-state requirements**:
The 2D renderer uses three GPU pipelines, split by **register pressure** (main vs effects) and
**render-pass structure** (everything vs backdrop):
1. **Main pipeline** — shapes (SDF and tessellated) and text. Low register footprint (~18–22
registers per thread). Runs at high GPU occupancy. Handles 90%+ of all fragments in a typical
frame.
1. **Main pipeline** — shapes (SDF and tessellated), text, and textured rectangles. Low register
footprint (~18–24 registers per thread). Runs at full GPU occupancy on every architecture.
Handles 90%+ of all fragments in a typical frame.
2. **Effects pipeline** — drop shadows, inner shadows, outer glow, and similar ALU-bound blur
effects. Medium register footprint (~48–60 registers). Each effects primitive includes the base
shape's SDF so that it can draw both the effect and the shape in a single fragment pass, avoiding
redundant overdraw.
redundant overdraw. Separated from the main pipeline to protect main-pipeline occupancy on
low-end hardware (see register analysis below).
3. **Backdrop-effects pipeline** — frosted glass, refraction, and any effect that samples the current
render target as input. High register footprint (~70–80 registers) and structurally requires a
`CopyGPUTextureToTexture` from the render target before drawing. Separated both for register
pressure and because the texture-copy requirement forces a render-pass-level state change.
3. **Backdrop pipeline** — frosted glass, refraction, and any effect that samples the current render
target as input. Implemented as a multi-pass sequence (downsample, separable blur, composite),
where each individual pass has a low-to-medium register footprint (~15–40 registers). Separated
from the other pipelines because it structurally requires ending the current render pass and
copying the render target before any backdrop-sampling fragment can execute — a command-buffer-
level boundary that cannot be avoided regardless of shader complexity.
A typical UI frame with no effects uses 1 pipeline bind and 0 switches. A frame with drop shadows
uses 2 pipelines and 1 switch. A frame with shadows and frosted glass uses all 3 pipelines and 2
switches plus 1 texture copy. At ~5μs per pipeline bind on modern APIs, worst-case switching overhead
is under 0.15% of an 8.3ms (120 FPS) frame budget.
switches plus 1 texture copy. At ~1–5μs per pipeline bind on modern APIs, worst-case switching
overhead is negligible relative to an 8.3ms (120 FPS) frame budget.
### Why three pipelines, not one or seven
The natural question is whether we should use a single unified pipeline (fewer state changes, simpler
code) or many per-primitive-type pipelines (no branching overhead, lean per-shader register usage).
The dominant cost factor is **GPU register pressure**, not pipeline switching overhead or fragment
shader branching. A GPU shader core has a fixed register pool shared among all concurrent threads. The
compiler allocates registers pessimistically based on the worst-case path through the shader. If the
shader contains both a 20-register RRect SDF and a 72-register frosted-glass blur, _every_ fragment
— even trivial RRects — is allocated 72 registers. This directly reduces **occupancy** (the number of
warps that can run simultaneously), which reduces the GPU's ability to hide memory latency.
#### Main/effects split: register pressure
Concrete example on a modern NVIDIA SM with 65,536 registers:
A GPU shader core has a fixed register pool shared among all concurrent threads. The compiler
allocates registers pessimistically based on the worst-case path through the shader. If the shader
contains both a 20-register RRect SDF and a 48-register drop-shadow blur, _every_ fragment — even
trivial RRects — is allocated 48 registers. This directly reduces **occupancy** (the number of
warps/wavefronts that can run simultaneously), which reduces the GPU's ability to hide memory
latency.
| Register allocation | Max concurrent threads | Occupancy |
| ------------------------- | ---------------------- | --------- |
| 20 regs (RRect only) | 3,276 | ~100% |
| 48 regs (+ drop shadow) | 1,365 | ~42% |
| 72 regs (+ frosted glass) | 910 | ~28% |
Each GPU architecture has a **register cliff** — a threshold above which occupancy starts dropping.
Below the cliff, adding registers has zero occupancy cost.
For a 4K frame (3840×2160) at 1.5× overdraw (~12.4M fragments), running all fragments at 28%
occupancy instead of 100% roughly triples fragment shading time. At 4K this is severe: if the main
pipeline's fragment work at full occupancy takes ~2ms, a single unified shader containing the glass
branch would push it to ~6ms — consuming 72% of the 8.3ms budget available at 120 FPS and leaving
almost nothing for CPU work, uploads, and presentation. This is a per-frame multiplier, not a
per-primitive cost — it applies even when the heavy branch is never taken.
On consumer Ampere/Ada GPUs (RTX 30xx/40xx, 65,536 regs/SM, max 1,536 threads/SM, cliff at ~43 regs):
The three-pipeline split groups primitives by register footprint so that:
| Register allocation | Reg-limited threads | Actual (hw-capped) | Occupancy |
| ----------------------- | ------------------- | ------------------ | --------- |
| 20 regs (main pipeline) | 3,276 | 1,536 | 100% |
| 32 regs | 2,048 | 1,536 | 100% |
| 48 regs (effects) | 1,365 | 1,365 | ~89% |
- Main pipeline (~20 regs): 90%+ of fragments run at near-full occupancy.
- Effects pipeline (~55 regs): shadow/glow fragments run at moderate occupancy; unavoidable given the
blur math complexity.
- Backdrop-effects pipeline (~75 regs): glass fragments run at low occupancy; also unavoidable, and
structurally separated anyway by the texture-copy requirement.
On Volta/A100 GPUs (65,536 regs/SM, max 2,048 threads/SM, cliff at ~32 regs):
This avoids the register-pressure tax of a single unified shader while keeping pipeline count minimal
(3 vs. Zed GPUI's 7). The effects that drag occupancy down are isolated to the fragments that
actually need them.
| Register allocation | Reg-limited threads | Actual (hw-capped) | Occupancy |
| ----------------------- | ------------------- | ------------------ | --------- |
| 20 regs (main pipeline) | 3,276 | 2,048 | 100% |
| 32 regs | 2,048 | 2,048 | 100% |
| 48 regs (effects) | 1,365 | 1,365 | ~67% |
**Why not per-primitive-type pipelines (GPUI's approach)?** Zed's GPUI uses 7 separate shader pairs:
On low-end mobile (ARM Mali Bifrost/Valhall, 64 regs/thread, cliff fixed at 32 regs):
| Register allocation | Occupancy |
| -------------------- | -------------------------- |
| 0–32 regs (main) | 100% (full thread count) |
| 33–64 regs (effects) | ~50% (thread count halves) |
Mali's cliff at 32 registers is the binding constraint. On desktop the occupancy difference between
20 and 48 registers is modest (89–100%); on Mali it is a hard 2× throughput reduction. The
main/effects split protects 90%+ of a frame's fragments (shapes, text, textures) from the effects
pipeline's register cost.
For the effects pipeline's drop-shadow shader — erf-approximation blur math with several texture
fetches — 50% occupancy on Mali roughly halves throughput. At 4K with 1.5× overdraw (~12.4M
fragments), a single unified shader containing the shadow branch would cost ~4ms instead of ~2ms on
low-end mobile. This is a per-frame multiplier even when the heavy branch is never taken, because the
compiler allocates registers for the worst-case path.
All main-pipeline members (SDF shapes, tessellated geometry, text, textured rectangles) cluster at
12–24 registers — below the cliff on every architecture — so unifying them costs nothing in
occupancy.
**Note on Apple M3+ GPUs:** Apple's M3 introduces Dynamic Caching (register file virtualization),
which allocates registers at runtime based on actual usage rather than worst-case. This weakens the
static register-pressure argument on M3 and later, but the split remains useful for isolating blur
ALU complexity and keeping the backdrop texture-copy out of the main render pass.
#### Backdrop split: render-pass structure
The backdrop pipeline (frosted glass, refraction, mirror surfaces) is separated for a structural
reason unrelated to register pressure. Before any backdrop-sampling fragment can execute, the current
render target must be copied to a separate texture via `CopyGPUTextureToTexture` — a command-buffer-
level operation that requires ending the current render pass. This boundary exists regardless of
shader complexity and cannot be optimized away.
The backdrop pipeline's individual shader passes (downsample, separable blur, composite) are
register-light (~15–40 regs each), so merging them into the effects pipeline would cause no occupancy
problem. But the render-pass boundary makes merging structurally impossible — effects draws happen
inside the main render pass, backdrop draws happen inside their own bracketed pass sequence.
#### Why not per-primitive-type pipelines (GPUI's approach)
Zed's GPUI uses 7 separate shader pairs:
quad, shadow, underline, monochrome sprite, polychrome sprite, path, surface. This eliminates all
branching and gives each shader minimal register usage. Three concrete costs make this approach wrong
for our use case:
@@ -120,7 +159,7 @@ typical UI frame with 15 scissors and 3–4 primitive kinds per scissor, per-kin
~45–60 draw calls and pipeline binds; our unified approach produces ~15–20 draw calls and 1–5
pipeline binds. At ~5μs each for CPU-side command encoding on modern APIs, per-kind splitting adds
375–500μs of CPU overhead per frame — **4.5–6% of an 8.3ms (120 FPS) budget** — with no
compensating GPU-side benefit, because the register-pressure savings within the simple-SDF tier are
compensating GPU-side benefit, because the register-pressure savings within the simple-SDF range are
negligible (all members cluster at 12–22 registers).
**Z-order preservation forces the API to expose layers.** With a single pipeline drawing all kinds
@@ -159,10 +198,10 @@ in submission order:
~60 boundary warps at ~80 extra instructions each), unified divergence costs ~13μs — still 3.5×
cheaper than the pipeline-switching alternative.
The split we _do_ perform (main / effects / backdrop-effects) is motivated by register-pressure tier
boundaries where occupancy differences are catastrophic at 4K (see numbers above). Within a tier,
unified is strictly better by every measure: fewer draw calls, simpler Z-order, lower CPU overhead,
and negligible GPU-side branching cost.
The split we _do_ perform (main / effects / backdrop) is motivated by register-pressure boundaries
and structural render-pass requirements (see analysis above). Within a pipeline, unified is
strictly better by every measure: fewer draw calls, simpler Z-order, lower CPU overhead, and
negligible GPU-side branching cost.
**References:**
@@ -172,6 +211,16 @@ and negligible GPU-side branching cost.
https://github.com/zed-industries/zed/blob/cb6fc11/crates/gpui/src/platform/mac/shaders.metal
- NVIDIA Nsight Graphics 2024.3 documentation on active-threads-per-warp and divergence analysis:
https://developer.nvidia.com/blog/optimize-gpu-workloads-for-graphics-applications-with-nvidia-nsight-graphics/
- NVIDIA Ampere GPU Architecture Tuning Guide — SM specs, max warps per SM (48 for cc 8.6, 64 for
cc 8.0), register file size (64K), occupancy factors:
https://docs.nvidia.com/cuda/ampere-tuning-guide/index.html
- NVIDIA Ada GPU Architecture Tuning Guide — SM specs, max warps per SM (48 for cc 8.9):
https://docs.nvidia.com/cuda/ada-tuning-guide/index.html
- CUDA Occupancy Calculation walkthrough (register allocation granularity, worked examples):
https://leimao.github.io/blog/CUDA-Occupancy-Calculation/
- Apple M3 GPU architecture — Dynamic Caching (register file virtualization) eliminates static
worst-case register allocation, reducing the occupancy penalty for high-register shaders:
https://asplos.dev/wiki/m3-chip-explainer/gpu/index.html
### Why fragment shader branching is safe in this design
@@ -442,25 +491,40 @@ Wallace's variant) and vger-rs.
- Vello's implementation of blurred rounded rectangle as a gradient type:
https://github.com/linebender/vello/pull/665
### Backdrop-effects pipeline
### Backdrop pipeline
The backdrop-effects pipeline handles effects that sample the current render target as input: frosted
glass, refraction, mirror surfaces. It is structurally separated from the effects pipeline for two
reasons:
The backdrop pipeline handles effects that sample the current render target as input: frosted glass,
refraction, mirror surfaces. It is separated from the effects pipeline for a structural reason, not
register pressure.
1. **Render-state requirement.** Before any backdrop-sampling fragment can run, the current render
target must be copied to a separate texture via `CopyGPUTextureToTexture`. This is a command-
buffer-level operation that cannot happen mid-render-pass. The copy naturally creates a pipeline
boundary.
**Render-pass boundary.** Before any backdrop-sampling fragment can run, the current render target
must be copied to a separate texture via `CopyGPUTextureToTexture`. This is a command-buffer-level
operation that cannot happen mid-render-pass. The copy naturally creates a pipeline boundary that no
amount of shader optimization can eliminate — it is a fundamental requirement of sampling a surface
while also writing to it.
2. **Register pressure.** Backdrop-sampling shaders read from a texture with Gaussian kernel weights
(multiple texture fetches per fragment), pushing register usage to ~70–80. Including this in the
effects pipeline would reduce occupancy for all shadow/glow fragments from ~30% to ~20%, costing
measurable throughput on the common case.
**Multi-pass implementation.** Backdrop effects are implemented as separable multi-pass sequences
(downsample → horizontal blur → vertical blur → composite), following the standard approach used by
iOS `UIVisualEffectView`, Android `RenderEffect`, and Flutter's `BackdropFilter`. Each individual
pass has a low-to-medium register footprint (~15–40 registers), well within the main pipeline's
occupancy range. The multi-pass approach avoids the monolithic 70+ register shader that a single-pass
Gaussian blur would require, making backdrop effects viable on low-end mobile GPUs (including
Mali-G31 and VideoCore VI) where per-thread register limits are tight.
The backdrop-effects pipeline binds a secondary sampler pointing at the captured backdrop texture. When
no backdrop effects are present in a frame, this pipeline is never bound and the texture copy never
happens — zero cost.
**Bracketed execution.** All backdrop draws in a frame share a single bracketed region of the command
buffer: end the current render pass, copy the render target, execute all backdrop sub-passes, then
resume normal drawing. The entry/exit cost (texture copy + render-pass break) is paid once per frame
regardless of how many backdrop effects are visible. When no backdrop effects are present, the bracket
is never entered and the texture copy never happens — zero cost.
**Why not split the backdrop sub-passes into separate pipelines?** The individual passes range from
~15 to ~40 registers, which does cross Mali's 32-register cliff. However, the register-pressure argument
that justifies the main/effects split does not apply here. The main/effects split protects the
_common path_ (90%+ of frame fragments) from the uncommon path's register cost. Inside the backdrop
pipeline there is no common-vs-uncommon distinction — if backdrop effects are active, every sub-pass
runs; if not, none run. The backdrop pipeline either executes as a complete unit or not at all.
Additionally, backdrop effects cover a small fraction of the frame's total fragments (~5% at typical
UI scales), so the occupancy variation within the bracket has negligible impact on frame time.
### Vertex layout
@@ -483,19 +547,21 @@ The `Primitive` struct for SDF shapes lives in the storage buffer, not in vertex
```
Primitive :: struct {
kind: Shape_Kind, // 0: enum u8
flags: Shape_Flags, // 1: bit_set[Shape_Flag; u8]
_pad: u16, // 2: reserved
bounds: [4]f32, // 4: min_x, min_y, max_x, max_y
color: Color, // 20: u8x4
_pad2: [3]u8, // 24: alignment
params: Shape_Params, // 28: raw union, 32 bytes
bounds: [4]f32, // 0: min_x, min_y, max_x, max_y
color: Color, // 16: u8x4, unpacked in shader via unpackUnorm4x8
kind_flags: u32, // 20: (kind as u32) | (flags as u32 << 8)
rotation: f32, // 24: shader self-rotation in radians
_pad: f32, // 28: alignment
params: Shape_Params, // 32: raw union, 32 bytes (two vec4s of shape-specific data)
uv_rect: [4]f32, // 64: texture UV sub-region (u_min, v_min, u_max, v_max)
}
// Total: 60 bytes (padded to 64 for GPU alignment)
// Total: 80 bytes (std430 aligned)
```
`Shape_Params` is a `#raw_union` with named variants per shape kind (`rrect`, `circle`, `segment`,
etc.), ensuring type safety on the CPU side and zero-cost reinterpretation on the GPU side.
etc.), ensuring type safety on the CPU side and zero-cost reinterpretation on the GPU side. The
`uv_rect` field is used by textured SDF primitives (Shape_Flag.Textured); non-textured primitives
leave it zeroed.
### Draw submission order
@@ -506,7 +572,7 @@ Within each scissor region, draws are issued in submission order to preserve the
2. Bind **main pipeline, tessellated mode** → draw all queued tessellated vertices (non-indexed for
shapes, indexed for text). Pipeline state unchanged from today.
3. Bind **main pipeline, SDF mode** → draw all queued SDF primitives (instanced, one draw call).
4. If backdrop effects are present: copy render target, bind **backdrop-effects pipeline** → draw
4. If backdrop effects are present: copy render target, bind **backdrop pipeline** → draw
backdrop primitives.
The exact ordering within a scissor may be refined based on actual Z-ordering requirements. The key
@@ -539,12 +605,180 @@ changes.
- Valve's original SDF text rendering paper (SIGGRAPH 2007):
https://steamcdn-a.akamaihd.net/apps/valve/2007/SIGGRAPH2007_AlphaTestedMagnification.pdf
### Textures
Textures plug into the existing main pipeline — no additional GPU pipeline, no shader rewrite. The
work is a resource layer (registration, upload, sampling, lifecycle) plus two textured-draw procs
that route into the existing tessellated and SDF paths respectively.
#### Why draw owns registered textures
A texture's GPU resource (the `^sdl.GPUTexture`, transfer buffer, shader resource view) is created
and destroyed by draw. The user provides raw bytes and a descriptor at registration time; draw
uploads synchronously and returns an opaque `Texture_Id` handle. The user can free their CPU-side
bytes immediately after `register_texture` returns.
This follows the model used by the RAD Debugger's render layer (`src/render/render_core.h` in
EpicGamesExt/raddebugger, MIT license), where `r_tex2d_alloc` takes `(kind, size, format, data)`
and returns an opaque handle that the renderer owns and releases. The single-owner model eliminates
an entire class of lifecycle bugs (double-free, use-after-free across subsystems, unclear cleanup
responsibility) that dual-ownership designs introduce.
If advanced interop is ever needed (e.g., a future 3D pipeline or compute shader sharing the same
GPU texture), the clean extension is a borrowed-reference accessor (`get_gpu_texture(id)`) that
returns the underlying handle without transferring ownership. This is purely additive and does not
require changing the registration API.
#### Why `Texture_Kind` exists
`Texture_Kind` (Static / Dynamic / Stream) is a driver hint for update frequency, adopted from the
RAD Debugger's `R_ResourceKind`. It maps directly to SDL3 GPU usage patterns:
- **Static**: uploaded once, never changes. Covers QR codes, decoded PNGs, icons — the 90% case.
- **Dynamic**: updatable via `update_texture_region`. Covers font atlas growth, procedural updates.
- **Stream**: frequent full re-uploads. Covers video playback, per-frame procedural generation.
This costs one byte in the descriptor and lets the backend pick optimal memory placement without a
future API change.
#### Why samplers are per-draw, not per-texture
A sampler describes how to filter and address a texture during sampling — nearest vs bilinear, clamp
vs repeat. This is a property of the _draw_, not the texture. The same QR code texture should be
sampled with `Nearest_Clamp` when displayed at native resolution but could reasonably be sampled
with `Linear_Clamp` in a zoomed-out thumbnail. The same icon atlas might be sampled with
`Nearest_Clamp` for pixel art or `Linear_Clamp` for smooth scaling.
The RAD Debugger follows this pattern: `R_BatchGroup2DParams` carries `tex_sample_kind` alongside
the texture handle, chosen per batch group at draw time. We do the same — `Sampler_Preset` is a
parameter on the draw procs, not a field on `Texture_Desc`.
Internally, draw keeps a small pool of pre-created `^sdl.GPUSampler` objects (one per preset,
lazily initialized). Sub-batch coalescing keys on `(kind, texture_id, sampler_preset)` — draws
with the same texture but different samplers produce separate draw calls, which is correct.
#### Textured draw procs
Textured rectangles route through the existing SDF path via `draw.rectangle_texture` and
`draw.rectangle_texture_corners`, mirroring `draw.rectangle` and `draw.rectangle_corners` exactly —
same parameters, same naming — with the color parameter replaced by a texture ID plus an optional
tint.
An earlier iteration of this design considered a separate tessellated `draw.texture` proc for
"simple" fullscreen quads, on the theory that the tessellated path's lower register count (~16 regs
vs ~24 for the SDF textured branch) would improve occupancy at large fragment counts. Applying the
register-pressure analysis from the pipeline-strategy section above shows this is wrong: both 16 and
24 registers are well below the register cliff (~43 regs on consumer Ampere/Ada, ~32 on Volta/A100),
so both run at 100% occupancy. The remaining ALU difference (~15 extra instructions for the SDF
evaluation) amounts to ~20μs at 4K — below noise. Meanwhile, splitting into a separate pipeline
would add ~1–5μs per pipeline bind on the CPU side per scissor, matching or exceeding the GPU-side
savings. Within the main pipeline, unified remains strictly better.
The naming convention follows the existing shape API: `rectangle_texture` and
`rectangle_texture_corners` sit alongside `rectangle` and `rectangle_corners`, mirroring the
`rectangle_gradient` / `circle_gradient` pattern where the shape is the primary noun and the
modifier (gradient, texture) is secondary. This groups related procs together in autocomplete
(`rectangle_*`) and reads as natural English ("draw a rectangle with a texture").
Future per-shape texture variants (`circle_texture`, `ellipse_texture`, `polygon_texture`) are
reserved by this naming convention and require only a `Shape_Flag.Textured` bit plus a small
per-shape UV mapping function in the fragment shader. These are additive.
#### What SDF anti-aliasing does and does not do for textured draws
The SDF path anti-aliases the **shape's outer silhouette** — rounded-corner edges, rotated edges,
stroke outlines. It does not anti-alias or sharpen the texture content. Inside the shape, fragments
sample through the chosen `Sampler_Preset`, and image quality is whatever the sampler produces from
the source texels. A low-resolution texture displayed at a large size shows bilinear blur regardless
of which draw proc is used. This matches the current text-rendering model, where glyph sharpness
depends on how closely the display size matches the SDL_ttf atlas's rasterized size.
#### Fit modes are a computation layer, not a renderer concept
Standard image-fit behaviors (stretch, fill/cover, fit/contain, tile, center) are expressed as UV
sub-region computations on top of the `uv_rect` parameter that both textured-draw procs accept. The
renderer has no knowledge of fit modes — it samples whatever UV region it is given.
A `fit_params` helper computes the appropriate `uv_rect`, sampler preset, and (for letterbox/fit
mode) shrunken inner rect from a `Fit_Mode` enum, the target rect, and the texture's pixel size.
Users who need custom UV control (sprite atlas sub-regions, UV animation, nine-patch slicing) skip
the helper and compute `uv_rect` directly. This keeps the renderer primitive minimal while making
the common cases convenient.
#### Deferred release
`unregister_texture` does not immediately release the GPU texture. It queues the slot for release at
the end of the current frame, after `SubmitGPUCommandBuffer` has handed work to the GPU. This
prevents a race condition where a texture is freed while the GPU is still sampling from it in an
already-submitted command buffer. The same deferred-release pattern is applied to `clear_text_cache`
and `clear_text_cache_entry`, fixing a pre-existing latent bug where destroying a cached
`^sdl_ttf.Text` mid-frame could free an atlas texture still referenced by in-flight draw batches.
This pattern is standard in production renderers — the RAD Debugger's `r_tex2d_release` queues
textures onto a free list that is processed in `r_end_frame`, not at the call site.
#### Clay integration
Clay's `RenderCommandType.Image` is handled by dereferencing `imageData: rawptr` as a pointer to a
`Clay_Image_Data` struct containing a `Texture_Id`, `Fit_Mode`, and tint color. Routing mirrors the
existing rectangle handling: zero `cornerRadius` dispatches to `draw.texture` (tessellated), nonzero
dispatches to `draw.rectangle_texture_corners` (SDF). A `fit_params` call computes UVs from the fit
mode before dispatch.
#### Deferred features
The following are plumbed in the descriptor but not implemented in phase 1:
- **Mipmaps**: `Texture_Desc.mip_levels` field exists; generation via SDL3 deferred.
- **Compressed formats**: `Texture_Desc.format` accepts BC/ASTC; upload path deferred.
- **Render-to-texture**: `Texture_Desc.usage` accepts `.COLOR_TARGET`; render-pass refactor deferred.
- **3D textures, arrays, cube maps**: `Texture_Desc.type` and `depth_or_layers` fields exist.
- **Additional samplers**: anisotropic, trilinear, clamp-to-border — additive enum values.
- **Atlas packing**: internal optimization for sub-batch coalescing; invisible to callers.
- **Per-shape texture variants**: `circle_texture`, `ellipse_texture`, etc. — reserved by naming.
**References:**
- RAD Debugger render layer (ownership model, deferred release, sampler-at-draw-time):
https://github.com/EpicGamesExt/raddebugger — `src/render/render_core.h`, `src/render/d3d11/render_d3d11.c`
- Casey Muratori, Handmade Hero day 472 — texture handling as a renderer-owned resource concern,
atlases as a separate layer above the renderer.
## 3D rendering
3D pipeline architecture is under consideration and will be documented separately. The current
expectation is that 3D rendering will use dedicated pipelines (separate from the 2D pipelines)
sharing GPU resources (textures, samplers, command buffer lifecycle) with the 2D renderer.
## Multi-window support
The renderer currently assumes a single window via the global `GLOB` state. Multi-window support is
deferred but anticipated. When revisited, the RAD Debugger's bucket + pass-list model
(`src/draw/draw.h`, `src/draw/draw.c` in EpicGamesExt/raddebugger) is worth studying as a reference.
RAD separates draw submission from rendering via **buckets**. A `DR_Bucket` is an explicit handle
that accumulates an ordered list of render passes (`R_PassList`). The user creates a bucket, pushes
it onto a thread-local stack, issues draw calls (which target the top-of-stack bucket), then submits
the bucket to a specific window. Multiple buckets can exist simultaneously — one per window, or one
per UI panel that gets composited into a parent bucket via `dr_sub_bucket`. Implicit draw parameters
(clip rect, 2D transform, sampler mode, transparency) are managed via push/pop stacks scoped to each
bucket, so different windows can have independent clip and transform state without interference.
The key properties this gives RAD:
- **Per-window isolation.** Each window builds its own bucket with its own pass list and state stacks.
No global contention.
- **Thread-parallel building.** Each thread has its own draw context and arena. Multiple threads can
build buckets concurrently, then submit them to the render backend sequentially.
- **Compositing.** A pre-built bucket (e.g., a tooltip or overlay) can be injected into another
bucket with a transform applied, without rebuilding its draw calls.
For our library, the likely adaptation would be replacing the single `GLOB` with a per-window draw
context that users create and pass to `begin`/`end`, while keeping the explicit-parameter draw call
style rather than adopting RAD's implicit state stacks. Texture and sampler resources would remain
global (shared across windows), with only the per-frame staging buffers and layer/scissor state
becoming per-context.
## Building shaders
GLSL shader sources live in `shaders/source/`. Compiled outputs (SPIR-V and Metal Shading Language)

202
draw/draw.odin
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@@ -63,15 +63,17 @@ Rectangle :: struct {
}
Sub_Batch_Kind :: enum u8 {
Shapes, // non-indexed, white texture, mode 0
Shapes, // non-indexed, white texture or user texture, mode 0
Text, // indexed, atlas texture, mode 0
SDF, // instanced unit quad, white texture, mode 1
SDF, // instanced unit quad, white texture or user texture, mode 1
}
Sub_Batch :: struct {
kind: Sub_Batch_Kind,
offset: u32, // Shapes: vertex offset; Text: text_batch index; SDF: primitive index
count: u32, // Shapes: vertex count; Text: always 1; SDF: primitive count
kind: Sub_Batch_Kind,
offset: u32, // Shapes: vertex offset; Text: text_batch index; SDF: primitive index
count: u32, // Shapes: vertex count; Text: always 1; SDF: primitive count
texture_id: Texture_Id,
sampler: Sampler_Preset,
}
Layer :: struct {
@@ -95,35 +97,60 @@ Scissor :: struct {
GLOB: Global
Global :: struct {
odin_context: runtime.Context,
pipeline_2d_base: Pipeline_2D_Base,
text_cache: Text_Cache,
layers: [dynamic]Layer,
scissors: [dynamic]Scissor,
tmp_shape_verts: [dynamic]Vertex,
tmp_text_verts: [dynamic]Vertex,
tmp_text_indices: [dynamic]c.int,
tmp_text_batches: [dynamic]TextBatch,
tmp_primitives: [dynamic]Primitive,
tmp_sub_batches: [dynamic]Sub_Batch,
tmp_uncached_text: [dynamic]^sdl_ttf.Text, // Uncached TTF_Text objects to destroy after end()
clay_memory: [^]u8,
msaa_texture: ^sdl.GPUTexture,
curr_layer_index: uint,
max_layers: int,
max_scissors: int,
max_shape_verts: int,
max_text_verts: int,
max_text_indices: int,
max_text_batches: int,
max_primitives: int,
max_sub_batches: int,
dpi_scaling: f32,
msaa_width: u32,
msaa_height: u32,
sample_count: sdl.GPUSampleCount,
clay_z_index: i16,
cleared: bool,
// -- Per-frame staging (hottest — touched by every prepare/upload/clear cycle) --
tmp_shape_verts: [dynamic]Vertex, // Tessellated shape vertices staged for GPU upload.
tmp_text_verts: [dynamic]Vertex, // Text vertices staged for GPU upload.
tmp_text_indices: [dynamic]c.int, // Text index buffer staged for GPU upload.
tmp_text_batches: [dynamic]TextBatch, // Text atlas batch metadata for indexed drawing.
tmp_primitives: [dynamic]Primitive, // SDF primitives staged for GPU storage buffer upload.
tmp_sub_batches: [dynamic]Sub_Batch, // Sub-batch records that drive draw call dispatch.
tmp_uncached_text: [dynamic]^sdl_ttf.Text, // Uncached TTF_Text objects destroyed after end() submits.
layers: [dynamic]Layer, // Draw layers, each with its own scissor stack.
scissors: [dynamic]Scissor, // Scissor rects that clip drawing within each layer.
// -- Per-frame scalars (accessed during prepare and draw_layer) --
curr_layer_index: uint, // Index of the currently active layer.
dpi_scaling: f32, // Window DPI scale factor applied to all pixel coordinates.
clay_z_index: i16, // Tracks z-index for layer splitting during Clay batch processing.
cleared: bool, // Whether the render target has been cleared this frame.
// -- Pipeline (accessed every draw_layer call) --
pipeline_2d_base: Pipeline_2D_Base, // The unified 2D GPU pipeline (shaders, buffers, samplers).
device: ^sdl.GPUDevice, // GPU device handle, stored at init.
samplers: [SAMPLER_PRESET_COUNT]^sdl.GPUSampler, // Lazily-created sampler objects, one per Sampler_Preset.
// -- Deferred release (processed once per frame at frame boundary) --
pending_texture_releases: [dynamic]Texture_Id, // Deferred GPU texture releases, processed next frame.
pending_text_releases: [dynamic]^sdl_ttf.Text, // Deferred TTF_Text destroys, processed next frame.
// -- Textures (registration is occasional, binding is per draw call) --
texture_slots: [dynamic]Texture_Slot, // Registered texture slots indexed by Texture_Id.
texture_free_list: [dynamic]u32, // Recycled slot indices available for reuse.
// -- MSAA (once per frame in end()) --
msaa_texture: ^sdl.GPUTexture, // Intermediate render target for multi-sample resolve.
msaa_width: u32, // Cached width to detect when MSAA texture needs recreation.
msaa_height: u32, // Cached height to detect when MSAA texture needs recreation.
sample_count: sdl.GPUSampleCount, // Sample count chosen at init (._1 means MSAA disabled).
// -- Clay (once per frame in prepare_clay_batch) --
clay_memory: [^]u8, // Raw memory block backing Clay's internal arena.
// -- Text (occasional — font registration and text cache lookups) --
text_cache: Text_Cache, // Font registry, SDL_ttf engine, and cached TTF_Text objects.
// -- Resize tracking (cold — checked once per frame in resize_global) --
max_layers: int, // High-water marks for dynamic array shrink heuristic.
max_scissors: int,
max_shape_verts: int,
max_text_verts: int,
max_text_indices: int,
max_text_batches: int,
max_primitives: int,
max_sub_batches: int,
// -- Init-only (coldest — set once at init, never written again) --
odin_context: runtime.Context, // Odin context captured at init for use in callbacks.
}
Init_Options :: struct {
@@ -168,22 +195,30 @@ init :: proc(
}
GLOB = Global {
layers = make([dynamic]Layer, 0, INITIAL_LAYER_SIZE, allocator = allocator),
scissors = make([dynamic]Scissor, 0, INITIAL_SCISSOR_SIZE, allocator = allocator),
tmp_shape_verts = make([dynamic]Vertex, 0, BUFFER_INIT_SIZE, allocator = allocator),
tmp_text_verts = make([dynamic]Vertex, 0, BUFFER_INIT_SIZE, allocator = allocator),
tmp_text_indices = make([dynamic]c.int, 0, BUFFER_INIT_SIZE, allocator = allocator),
tmp_text_batches = make([dynamic]TextBatch, 0, BUFFER_INIT_SIZE, allocator = allocator),
tmp_primitives = make([dynamic]Primitive, 0, BUFFER_INIT_SIZE, allocator = allocator),
tmp_sub_batches = make([dynamic]Sub_Batch, 0, BUFFER_INIT_SIZE, allocator = allocator),
tmp_uncached_text = make([dynamic]^sdl_ttf.Text, 0, 16, allocator = allocator),
odin_context = odin_context,
dpi_scaling = sdl.GetWindowDisplayScale(window),
clay_memory = make([^]u8, min_memory_size, allocator = allocator),
sample_count = resolved_sample_count,
pipeline_2d_base = pipeline,
text_cache = text_cache,
layers = make([dynamic]Layer, 0, INITIAL_LAYER_SIZE, allocator = allocator),
scissors = make([dynamic]Scissor, 0, INITIAL_SCISSOR_SIZE, allocator = allocator),
tmp_shape_verts = make([dynamic]Vertex, 0, BUFFER_INIT_SIZE, allocator = allocator),
tmp_text_verts = make([dynamic]Vertex, 0, BUFFER_INIT_SIZE, allocator = allocator),
tmp_text_indices = make([dynamic]c.int, 0, BUFFER_INIT_SIZE, allocator = allocator),
tmp_text_batches = make([dynamic]TextBatch, 0, BUFFER_INIT_SIZE, allocator = allocator),
tmp_primitives = make([dynamic]Primitive, 0, BUFFER_INIT_SIZE, allocator = allocator),
tmp_sub_batches = make([dynamic]Sub_Batch, 0, BUFFER_INIT_SIZE, allocator = allocator),
tmp_uncached_text = make([dynamic]^sdl_ttf.Text, 0, 16, allocator = allocator),
device = device,
texture_slots = make([dynamic]Texture_Slot, 0, 16, allocator = allocator),
texture_free_list = make([dynamic]u32, 0, 16, allocator = allocator),
pending_texture_releases = make([dynamic]Texture_Id, 0, 16, allocator = allocator),
pending_text_releases = make([dynamic]^sdl_ttf.Text, 0, 16, allocator = allocator),
odin_context = odin_context,
dpi_scaling = sdl.GetWindowDisplayScale(window),
clay_memory = make([^]u8, min_memory_size, allocator = allocator),
sample_count = resolved_sample_count,
pipeline_2d_base = pipeline,
text_cache = text_cache,
}
// Reserve slot 0 for INVALID_TEXTURE
append(&GLOB.texture_slots, Texture_Slot{})
log.debug("Window DPI scaling:", GLOB.dpi_scaling)
arena := clay.CreateArenaWithCapacityAndMemory(min_memory_size, GLOB.clay_memory)
window_width, window_height: c.int
@@ -230,12 +265,23 @@ destroy :: proc(device: ^sdl.GPUDevice, allocator := context.allocator) {
if GLOB.msaa_texture != nil {
sdl.ReleaseGPUTexture(device, GLOB.msaa_texture)
}
process_pending_texture_releases()
destroy_all_textures()
destroy_sampler_pool()
for ttf_text in GLOB.pending_text_releases do sdl_ttf.DestroyText(ttf_text)
delete(GLOB.pending_text_releases)
destroy_pipeline_2d_base(device, &GLOB.pipeline_2d_base)
destroy_text_cache()
}
// Internal
clear_global :: proc() {
// Process deferred texture releases from the previous frame
process_pending_texture_releases()
// Process deferred text releases from the previous frame
for ttf_text in GLOB.pending_text_releases do sdl_ttf.DestroyText(ttf_text)
clear(&GLOB.pending_text_releases)
GLOB.curr_layer_index = 0
GLOB.clay_z_index = 0
GLOB.cleared = false
@@ -265,6 +311,7 @@ measure_text_clay :: proc "c" (
context = GLOB.odin_context
text := string(text.chars[:text.length])
c_text := strings.clone_to_cstring(text, context.temp_allocator)
defer delete(c_text, context.temp_allocator)
width, height: c.int
if !sdl_ttf.GetStringSize(get_font(config.fontId, config.fontSize), c_text, 0, &width, &height) {
log.panicf("Failed to measure text: %s", sdl.GetError())
@@ -454,15 +501,24 @@ append_or_extend_sub_batch :: proc(
kind: Sub_Batch_Kind,
offset: u32,
count: u32,
texture_id: Texture_Id = INVALID_TEXTURE,
sampler: Sampler_Preset = .Linear_Clamp,
) {
if scissor.sub_batch_len > 0 {
last := &GLOB.tmp_sub_batches[scissor.sub_batch_start + scissor.sub_batch_len - 1]
if last.kind == kind && kind != .Text && last.offset + last.count == offset {
if last.kind == kind &&
kind != .Text &&
last.offset + last.count == offset &&
last.texture_id == texture_id &&
last.sampler == sampler {
last.count += count
return
}
}
append(&GLOB.tmp_sub_batches, Sub_Batch{kind = kind, offset = offset, count = count})
append(
&GLOB.tmp_sub_batches,
Sub_Batch{kind = kind, offset = offset, count = count, texture_id = texture_id, sampler = sampler},
)
scissor.sub_batch_len += 1
layer.sub_batch_len += 1
}
@@ -502,6 +558,7 @@ prepare_clay_batch :: proc(
mouse_wheel_delta: [2]f32,
frame_time: f32 = 0,
custom_draw: Custom_Draw = nil,
temp_allocator := context.temp_allocator,
) {
mouse_pos: [2]f32
mouse_flags := sdl.GetMouseState(&mouse_pos.x, &mouse_pos.y)
@@ -541,7 +598,8 @@ prepare_clay_batch :: proc(
case clay.RenderCommandType.Text:
render_data := render_command.renderData.text
txt := string(render_data.stringContents.chars[:render_data.stringContents.length])
c_text := strings.clone_to_cstring(txt, context.temp_allocator)
c_text := strings.clone_to_cstring(txt, temp_allocator)
defer delete(c_text, temp_allocator)
// Clay render-command IDs are derived via Clay's internal HashNumber (Jenkins-family)
// and namespaced with .Clay so they can never collide with user-provided custom text IDs.
sdl_text := cache_get_or_update(
@@ -551,6 +609,46 @@ prepare_clay_batch :: proc(
)
prepare_text(layer, Text{sdl_text, {bounds.x, bounds.y}, color_from_clay(render_data.textColor)})
case clay.RenderCommandType.Image:
render_data := render_command.renderData.image
if render_data.imageData == nil do continue
img_data := (^Clay_Image_Data)(render_data.imageData)^
cr := render_data.cornerRadius
radii := [4]f32{cr.topLeft, cr.topRight, cr.bottomRight, cr.bottomLeft}
// Background color behind the image (Clay allows it)
bg := color_from_clay(render_data.backgroundColor)
if bg[3] > 0 {
if radii == {0, 0, 0, 0} {
rectangle(layer, bounds, bg)
} else {
rectangle_corners(layer, bounds, radii, bg)
}
}
// Compute fit UVs
uv, sampler, inner := fit_params(img_data.fit, bounds, img_data.texture_id)
// Draw the image — route by cornerRadius
if radii == {0, 0, 0, 0} {
rectangle_texture(
layer,
inner,
img_data.texture_id,
tint = img_data.tint,
uv_rect = uv,
sampler = sampler,
)
} else {
rectangle_texture_corners(
layer,
inner,
radii,
img_data.texture_id,
tint = img_data.tint,
uv_rect = uv,
sampler = sampler,
)
}
case clay.RenderCommandType.ScissorStart:
if bounds.width == 0 || bounds.height == 0 do continue

175
draw/draw_qr/draw_qr.odin Normal file
View File

@@ -0,0 +1,175 @@
package draw_qr
import draw ".."
import "../../qrcode"
// Returns the number of bytes to_texture will write for the given encoded
// QR buffer. Equivalent to size*size*4 where size = qrcode.get_size(qrcode_buf).
texture_size :: #force_inline proc(qrcode_buf: []u8) -> int {
size := qrcode.get_size(qrcode_buf)
return size * size * 4
}
// Decodes an encoded QR buffer into tightly-packed RGBA pixel data written to
// texture_buf. No allocations, no GPU calls. Returns the Texture_Desc the
// caller should pass to draw.register_texture alongside texture_buf.
//
// Returns ok=false when:
// - qrcode_buf is invalid (qrcode.get_size returns 0).
// - texture_buf is smaller than to_texture_size(qrcode_buf).
@(require_results)
to_texture :: proc(
qrcode_buf: []u8,
texture_buf: []u8,
dark: draw.Color = draw.BLACK,
light: draw.Color = draw.WHITE,
) -> (
desc: draw.Texture_Desc,
ok: bool,
) {
size := qrcode.get_size(qrcode_buf)
if size == 0 do return {}, false
if len(texture_buf) < size * size * 4 do return {}, false
for y in 0 ..< size {
for x in 0 ..< size {
i := (y * size + x) * 4
c := dark if qrcode.get_module(qrcode_buf, x, y) else light
texture_buf[i + 0] = c[0]
texture_buf[i + 1] = c[1]
texture_buf[i + 2] = c[2]
texture_buf[i + 3] = c[3]
}
}
return draw.Texture_Desc {
width = u32(size),
height = u32(size),
depth_or_layers = 1,
type = .D2,
format = .R8G8B8A8_UNORM,
usage = {.SAMPLER},
mip_levels = 1,
kind = .Static,
},
true
}
// Allocates pixel buffer via temp_allocator, decodes qrcode_buf into it, and
// registers with the GPU. The pixel allocation is freed before return.
//
// Returns ok=false when:
// - qrcode_buf is invalid (qrcode.get_size returns 0).
// - temp_allocator fails to allocate the pixel buffer.
// - GPU texture registration fails.
@(require_results)
register_texture_from_raw :: proc(
qrcode_buf: []u8,
dark: draw.Color = draw.BLACK,
light: draw.Color = draw.WHITE,
temp_allocator := context.temp_allocator,
) -> (
texture: draw.Texture_Id,
ok: bool,
) {
tex_size := texture_size(qrcode_buf)
if tex_size == 0 do return draw.INVALID_TEXTURE, false
pixels, alloc_err := make([]u8, tex_size, temp_allocator)
if alloc_err != nil do return draw.INVALID_TEXTURE, false
defer delete(pixels, temp_allocator)
desc := to_texture(qrcode_buf, pixels, dark, light) or_return
return draw.register_texture(desc, pixels)
}
// Encodes text as a QR Code and registers the result as an RGBA texture.
//
// Returns ok=false when:
// - temp_allocator fails to allocate.
// - The text cannot fit in any version within [min_version, max_version] at the given ECL.
// - GPU texture registration fails.
@(require_results)
register_texture_from_text :: proc(
text: string,
ecl: qrcode.Ecc = .Low,
min_version: int = qrcode.VERSION_MIN,
max_version: int = qrcode.VERSION_MAX,
mask: Maybe(qrcode.Mask) = nil,
boost_ecl: bool = true,
dark: draw.Color = draw.BLACK,
light: draw.Color = draw.WHITE,
temp_allocator := context.temp_allocator,
) -> (
texture: draw.Texture_Id,
ok: bool,
) {
qrcode_buf, alloc_err := make([]u8, qrcode.buffer_len_for_version(max_version), temp_allocator)
if alloc_err != nil do return draw.INVALID_TEXTURE, false
defer delete(qrcode_buf, temp_allocator)
qrcode.encode_auto(
text,
qrcode_buf,
ecl,
min_version,
max_version,
mask,
boost_ecl,
temp_allocator,
) or_return
return register_texture_from_raw(qrcode_buf, dark, light, temp_allocator)
}
// Encodes arbitrary binary data as a QR Code and registers the result as an RGBA texture.
//
// Returns ok=false when:
// - temp_allocator fails to allocate.
// - The payload cannot fit in any version within [min_version, max_version] at the given ECL.
// - GPU texture registration fails.
@(require_results)
register_texture_from_binary :: proc(
bin_data: []u8,
ecl: qrcode.Ecc = .Low,
min_version: int = qrcode.VERSION_MIN,
max_version: int = qrcode.VERSION_MAX,
mask: Maybe(qrcode.Mask) = nil,
boost_ecl: bool = true,
dark: draw.Color = draw.BLACK,
light: draw.Color = draw.WHITE,
temp_allocator := context.temp_allocator,
) -> (
texture: draw.Texture_Id,
ok: bool,
) {
qrcode_buf, alloc_err := make([]u8, qrcode.buffer_len_for_version(max_version), temp_allocator)
if alloc_err != nil do return draw.INVALID_TEXTURE, false
defer delete(qrcode_buf, temp_allocator)
qrcode.encode_auto(
bin_data,
qrcode_buf,
ecl,
min_version,
max_version,
mask,
boost_ecl,
temp_allocator,
) or_return
return register_texture_from_raw(qrcode_buf, dark, light, temp_allocator)
}
register_texture_from :: proc {
register_texture_from_text,
register_texture_from_binary
}
// Default fit=.Fit preserves the QR's square aspect; override as needed.
clay_image :: #force_inline proc(
texture: draw.Texture_Id,
tint: draw.Color = draw.WHITE,
) -> draw.Clay_Image_Data {
return draw.clay_image_data(texture, fit = .Fit, tint = tint)
}

5
draw/examples/hellope.odin
View File

@@ -78,10 +78,11 @@ hellope_shapes :: proc() {
draw.ellipse(base_layer, {410, 340}, 50, 30, {255, 200, 50, 255}, rotation = spin_angle)
// Circle orbiting a point (moon orbiting planet)
// Convention B: center = pivot point (planet), origin = offset from moon center to pivot.
// Moon's visual center at rotation=0: planet_pos - origin = (100, 450) - (0, 40) = (100, 410).
planet_pos := [2]f32{100, 450}
moon_pos := planet_pos + {0, -40}
draw.circle(base_layer, planet_pos, 8, {200, 200, 200, 255}) // planet (stationary)
draw.circle(base_layer, moon_pos, 5, {100, 150, 255, 255}, origin = {0, 40}, rotation = spin_angle) // moon orbiting
draw.circle(base_layer, planet_pos, 5, {100, 150, 255, 255}, origin = {0, 40}, rotation = spin_angle) // moon orbiting
// Ring arc rotating in place
draw.ring(base_layer, {250, 450}, 15, 30, 0, 270, {100, 100, 220, 255}, rotation = spin_angle)

5
draw/examples/main.odin
View File

@@ -57,7 +57,7 @@ main :: proc() {
args := os.args
if len(args) < 2 {
fmt.eprintln("Usage: examples <example_name>")
fmt.eprintln("Available examples: hellope-shapes, hellope-text, hellope-clay, hellope-custom")
fmt.eprintln("Available examples: hellope-shapes, hellope-text, hellope-clay, hellope-custom, textures")
os.exit(1)
}
@@ -66,9 +66,10 @@ main :: proc() {
case "hellope-custom": hellope_custom()
case "hellope-shapes": hellope_shapes()
case "hellope-text": hellope_text()
case "textures": textures()
case:
fmt.eprintf("Unknown example: %v\n", args[1])
fmt.eprintln("Available examples: hellope-shapes, hellope-text, hellope-clay, hellope-custom")
fmt.eprintln("Available examples: hellope-shapes, hellope-text, hellope-clay, hellope-custom, textures")
os.exit(1)
}
}

272
draw/examples/textures.odin Normal file
View File

@@ -0,0 +1,272 @@
package examples
import "../../draw"
import "../../draw/draw_qr"
import "core:os"
import sdl "vendor:sdl3"
textures :: proc() {
if !sdl.Init({.VIDEO}) do os.exit(1)
window := sdl.CreateWindow("Textures", 800, 600, {.HIGH_PIXEL_DENSITY})
gpu := sdl.CreateGPUDevice(draw.PLATFORM_SHADER_FORMAT, true, nil)
if !sdl.ClaimWindowForGPUDevice(gpu, window) do os.exit(1)
if !draw.init(gpu, window) do os.exit(1)
JETBRAINS_MONO_REGULAR = draw.register_font(JETBRAINS_MONO_REGULAR_RAW)
FONT_SIZE :: u16(14)
LABEL_OFFSET :: f32(8) // gap between item and its label
//----- Texture registration ----------------------------------
checker_size :: 8
checker_pixels: [checker_size * checker_size * 4]u8
for y in 0 ..< checker_size {
for x in 0 ..< checker_size {
i := (y * checker_size + x) * 4
is_dark := ((x + y) % 2) == 0
val: u8 = 40 if is_dark else 220
checker_pixels[i + 0] = val // R
checker_pixels[i + 1] = val / 2 // G — slight color tint
checker_pixels[i + 2] = val // B
checker_pixels[i + 3] = 255 // A
}
}
checker_texture, _ := draw.register_texture(
draw.Texture_Desc {
width = checker_size,
height = checker_size,
depth_or_layers = 1,
type = .D2,
format = .R8G8B8A8_UNORM,
usage = {.SAMPLER},
mip_levels = 1,
},
checker_pixels[:],
)
defer draw.unregister_texture(checker_texture)
stripe_w :: 16
stripe_h :: 8
stripe_pixels: [stripe_w * stripe_h * 4]u8
for y in 0 ..< stripe_h {
for x in 0 ..< stripe_w {
i := (y * stripe_w + x) * 4
stripe_pixels[i + 0] = u8(x * 255 / (stripe_w - 1)) // R gradient left→right
stripe_pixels[i + 1] = u8(y * 255 / (stripe_h - 1)) // G gradient top→bottom
stripe_pixels[i + 2] = 128 // B constant
stripe_pixels[i + 3] = 255 // A
}
}
stripe_texture, _ := draw.register_texture(
draw.Texture_Desc {
width = stripe_w,
height = stripe_h,
depth_or_layers = 1,
type = .D2,
format = .R8G8B8A8_UNORM,
usage = {.SAMPLER},
mip_levels = 1,
},
stripe_pixels[:],
)
defer draw.unregister_texture(stripe_texture)
qr_texture, _ := draw_qr.register_texture_from("https://x.com/miiilato/status/1880241066471051443")
defer draw.unregister_texture(qr_texture)
spin_angle: f32 = 0
//----- Draw loop ----------------------------------
for {
defer free_all(context.temp_allocator)
ev: sdl.Event
for sdl.PollEvent(&ev) {
if ev.type == .QUIT do return
}
spin_angle += 1
base_layer := draw.begin({width = 800, height = 600})
// Background
draw.rectangle(base_layer, {0, 0, 800, 600}, {30, 30, 30, 255})
//----- Row 1: Sampler presets (y=30) ----------------------------------
ROW1_Y :: f32(30)
ITEM_SIZE :: f32(120)
COL1 :: f32(30)
COL2 :: f32(180)
COL3 :: f32(330)
COL4 :: f32(480)
// Nearest (sharp pixel edges)
draw.rectangle_texture(
base_layer,
{COL1, ROW1_Y, ITEM_SIZE, ITEM_SIZE},
checker_texture,
sampler = .Nearest_Clamp,
)
draw.text(
base_layer,
"Nearest",
{COL1, ROW1_Y + ITEM_SIZE + LABEL_OFFSET},
JETBRAINS_MONO_REGULAR,
FONT_SIZE,
color = draw.WHITE,
)
// Linear (bilinear blur)
draw.rectangle_texture(
base_layer,
{COL2, ROW1_Y, ITEM_SIZE, ITEM_SIZE},
checker_texture,
sampler = .Linear_Clamp,
)
draw.text(
base_layer,
"Linear",
{COL2, ROW1_Y + ITEM_SIZE + LABEL_OFFSET},
JETBRAINS_MONO_REGULAR,
FONT_SIZE,
color = draw.WHITE,
)
// Tiled (4x repeat)
draw.rectangle_texture(
base_layer,
{COL3, ROW1_Y, ITEM_SIZE, ITEM_SIZE},
checker_texture,
sampler = .Nearest_Repeat,
uv_rect = {0, 0, 4, 4},
)
draw.text(
base_layer,
"Tiled 4x",
{COL3, ROW1_Y + ITEM_SIZE + LABEL_OFFSET},
JETBRAINS_MONO_REGULAR,
FONT_SIZE,
color = draw.WHITE,
)
//----- Row 2: Sampler presets (y=190) ----------------------------------
ROW2_Y :: f32(190)
// QR code (RGBA texture with baked colors, nearest sampling)
draw.rectangle(base_layer, {COL1, ROW2_Y, ITEM_SIZE, ITEM_SIZE}, {255, 255, 255, 255}) // white bg
draw.rectangle_texture(
base_layer,
{COL1, ROW2_Y, ITEM_SIZE, ITEM_SIZE},
qr_texture,
sampler = .Nearest_Clamp,
)
draw.text(
base_layer,
"QR Code",
{COL1, ROW2_Y + ITEM_SIZE + LABEL_OFFSET},
JETBRAINS_MONO_REGULAR,
FONT_SIZE,
color = draw.WHITE,
)
// Rounded corners
draw.rectangle_texture(
base_layer,
{COL2, ROW2_Y, ITEM_SIZE, ITEM_SIZE},
checker_texture,
sampler = .Nearest_Clamp,
roundness = 0.3,
)
draw.text(
base_layer,
"Rounded",
{COL2, ROW2_Y + ITEM_SIZE + LABEL_OFFSET},
JETBRAINS_MONO_REGULAR,
FONT_SIZE,
color = draw.WHITE,
)
// Rotating
rot_rect := draw.Rectangle{COL3, ROW2_Y, ITEM_SIZE, ITEM_SIZE}
draw.rectangle_texture(
base_layer,
rot_rect,
checker_texture,
sampler = .Nearest_Clamp,
origin = draw.center_of(rot_rect),
rotation = spin_angle,
)
draw.text(
base_layer,
"Rotating",
{COL3, ROW2_Y + ITEM_SIZE + LABEL_OFFSET},
JETBRAINS_MONO_REGULAR,
FONT_SIZE,
color = draw.WHITE,
)
//----- Row 3: Fit modes + Per-corner radii (y=360) ----------------------------------
ROW3_Y :: f32(360)
FIT_SIZE :: f32(120) // square target rect
// Stretch
uv_s, sampler_s, inner_s := draw.fit_params(.Stretch, {COL1, ROW3_Y, FIT_SIZE, FIT_SIZE}, stripe_texture)
draw.rectangle(base_layer, {COL1, ROW3_Y, FIT_SIZE, FIT_SIZE}, {60, 60, 60, 255}) // bg
draw.rectangle_texture(base_layer, inner_s, stripe_texture, uv_rect = uv_s, sampler = sampler_s)
draw.text(
base_layer,
"Stretch",
{COL1, ROW3_Y + FIT_SIZE + LABEL_OFFSET},
JETBRAINS_MONO_REGULAR,
FONT_SIZE,
color = draw.WHITE,
)
// Fill (center-crop)
uv_f, sampler_f, inner_f := draw.fit_params(.Fill, {COL2, ROW3_Y, FIT_SIZE, FIT_SIZE}, stripe_texture)
draw.rectangle(base_layer, {COL2, ROW3_Y, FIT_SIZE, FIT_SIZE}, {60, 60, 60, 255})
draw.rectangle_texture(base_layer, inner_f, stripe_texture, uv_rect = uv_f, sampler = sampler_f)
draw.text(
base_layer,
"Fill",
{COL2, ROW3_Y + FIT_SIZE + LABEL_OFFSET},
JETBRAINS_MONO_REGULAR,
FONT_SIZE,
color = draw.WHITE,
)
// Fit (letterbox)
uv_ft, sampler_ft, inner_ft := draw.fit_params(.Fit, {COL3, ROW3_Y, FIT_SIZE, FIT_SIZE}, stripe_texture)
draw.rectangle(base_layer, {COL3, ROW3_Y, FIT_SIZE, FIT_SIZE}, {60, 60, 60, 255}) // visible margin bg
draw.rectangle_texture(base_layer, inner_ft, stripe_texture, uv_rect = uv_ft, sampler = sampler_ft)
draw.text(
base_layer,
"Fit",
{COL3, ROW3_Y + FIT_SIZE + LABEL_OFFSET},
JETBRAINS_MONO_REGULAR,
FONT_SIZE,
color = draw.WHITE,
)
// Per-corner radii
draw.rectangle_texture_corners(
base_layer,
{COL4, ROW3_Y, FIT_SIZE, FIT_SIZE},
{20, 0, 20, 0},
checker_texture,
sampler = .Nearest_Clamp,
)
draw.text(
base_layer,
"Per-corner",
{COL4, ROW3_Y + FIT_SIZE + LABEL_OFFSET},
JETBRAINS_MONO_REGULAR,
FONT_SIZE,
color = draw.WHITE,
)
draw.end(gpu, window)
}
}

37
draw/pipeline_2d_base.odin
View File

@@ -35,6 +35,7 @@ Shape_Kind :: enum u8 {
Shape_Flag :: enum u8 {
Stroke,
Textured,
}
Shape_Flags :: bit_set[Shape_Flag;u8]
@@ -106,9 +107,10 @@ Primitive :: struct {
rotation: f32, // 24: shader self-rotation in radians (used by RRect, Ellipse)
_pad: f32, // 28: alignment to vec4 boundary
params: Shape_Params, // 32: two vec4s of shape params
uv_rect: [4]f32, // 64: u_min, v_min, u_max, v_max (default {0,0,1,1})
}
#assert(size_of(Primitive) == 64)
#assert(size_of(Primitive) == 80)
pack_kind_flags :: #force_inline proc(kind: Shape_Kind, flags: Shape_Flags) -> u32 {
return u32(kind) | (u32(transmute(u8)flags) << 8)
@@ -566,6 +568,7 @@ draw_layer :: proc(
current_mode: Draw_Mode = .Tessellated
current_vert_buf := main_vert_buf
current_atlas: ^sdl.GPUTexture
current_sampler := sampler
// Text vertices live after shape vertices in the GPU vertex buffer
text_vertex_gpu_base := u32(len(GLOB.tmp_shape_verts))
@@ -584,14 +587,24 @@ draw_layer :: proc(
sdl.BindGPUVertexBuffers(render_pass, 0, &sdl.GPUBufferBinding{buffer = main_vert_buf, offset = 0}, 1)
current_vert_buf = main_vert_buf
}
if current_atlas != white_texture {
// Determine texture and sampler for this batch
batch_texture: ^sdl.GPUTexture = white_texture
batch_sampler: ^sdl.GPUSampler = sampler
if batch.texture_id != INVALID_TEXTURE {
if bound_texture := texture_gpu_handle(batch.texture_id); bound_texture != nil {
batch_texture = bound_texture
}
batch_sampler = get_sampler(batch.sampler)
}
if current_atlas != batch_texture || current_sampler != batch_sampler {
sdl.BindGPUFragmentSamplers(
render_pass,
0,
&sdl.GPUTextureSamplerBinding{texture = white_texture, sampler = sampler},
&sdl.GPUTextureSamplerBinding{texture = batch_texture, sampler = batch_sampler},
1,
)
current_atlas = white_texture
current_atlas = batch_texture
current_sampler = batch_sampler
}
sdl.DrawGPUPrimitives(render_pass, batch.count, 1, batch.offset, 0)
@@ -632,14 +645,24 @@ draw_layer :: proc(
sdl.BindGPUVertexBuffers(render_pass, 0, &sdl.GPUBufferBinding{buffer = unit_quad, offset = 0}, 1)
current_vert_buf = unit_quad
}
if current_atlas != white_texture {
// Determine texture and sampler for this batch
batch_texture: ^sdl.GPUTexture = white_texture
batch_sampler: ^sdl.GPUSampler = sampler
if batch.texture_id != INVALID_TEXTURE {
if bound_texture := texture_gpu_handle(batch.texture_id); bound_texture != nil {
batch_texture = bound_texture
}
batch_sampler = get_sampler(batch.sampler)
}
if current_atlas != batch_texture || current_sampler != batch_sampler {
sdl.BindGPUFragmentSamplers(
render_pass,
0,
&sdl.GPUTextureSamplerBinding{texture = white_texture, sampler = sampler},
&sdl.GPUTextureSamplerBinding{texture = batch_texture, sampler = batch_sampler},
1,
)
current_atlas = white_texture
current_atlas = batch_texture
current_sampler = batch_sampler
}
sdl.DrawGPUPrimitives(render_pass, 6, batch.count, 0, batch.offset)
}

95
draw/shaders/generated/base_2d.frag.metal
View File

@@ -25,6 +25,7 @@ struct main0_in
float4 f_params2 [[user(locn3)]];
uint f_kind_flags [[user(locn4)]];
float f_rotation [[user(locn5), flat]];
float4 f_uv_rect [[user(locn6), flat]];
};
static inline __attribute__((always_inline))
@@ -69,6 +70,12 @@ float sdf_stroke(thread const float& d, thread const float& stroke_width)
return abs(d) - (stroke_width * 0.5);
}
static inline __attribute__((always_inline))
float sdf_alpha(thread const float& d, thread const float& soft)
{
return 1.0 - smoothstep(-soft, soft, d);
}
static inline __attribute__((always_inline))
float sdCircle(thread const float2& p, thread const float& r)
{
@@ -127,12 +134,6 @@ float sdSegment(thread const float2& p, thread const float2& a, thread const flo
return length(pa - (ba * h));
}
static inline __attribute__((always_inline))
float sdf_alpha(thread const float& d, thread const float& soft)
{
return 1.0 - smoothstep(-soft, soft, d);
}
fragment main0_out main0(main0_in in [[stage_in]], texture2d<float> tex [[texture(0)]], sampler texSmplr [[sampler(0)]])
{
main0_out out = {};
@@ -169,6 +170,25 @@ fragment main0_out main0(main0_in in [[stage_in]], texture2d<float> tex [[textur
float param_6 = stroke_px;
d = sdf_stroke(param_5, param_6);
}
float4 shape_color = in.f_color;
if ((flags & 2u) != 0u)
{
float2 p_for_uv = in.f_local_or_uv;
if (in.f_rotation != 0.0)
{
float2 param_7 = p_for_uv;
float param_8 = in.f_rotation;
p_for_uv = apply_rotation(param_7, param_8);
}
float2 local_uv = ((p_for_uv / b) * 0.5) + float2(0.5);
float2 uv = mix(in.f_uv_rect.xy, in.f_uv_rect.zw, local_uv);
shape_color *= tex.sample(texSmplr, uv);
}
float param_9 = d;
float param_10 = soft;
float alpha = sdf_alpha(param_9, param_10);
out.out_color = float4(shape_color.xyz, shape_color.w * alpha);
return out;
}
else
{
@@ -177,14 +197,14 @@ fragment main0_out main0(main0_in in [[stage_in]], texture2d<float> tex [[textur
float radius = in.f_params.x;
soft = fast::max(in.f_params.y, 1.0);
float stroke_px_1 = in.f_params.z;
float2 param_7 = in.f_local_or_uv;
float param_8 = radius;
d = sdCircle(param_7, param_8);
float2 param_11 = in.f_local_or_uv;
float param_12 = radius;
d = sdCircle(param_11, param_12);
if ((flags & 1u) != 0u)
{
float param_9 = d;
float param_10 = stroke_px_1;
d = sdf_stroke(param_9, param_10);
float param_13 = d;
float param_14 = stroke_px_1;
d = sdf_stroke(param_13, param_14);
}
}
else
@@ -197,19 +217,19 @@ fragment main0_out main0(main0_in in [[stage_in]], texture2d<float> tex [[textur
float2 p_local_1 = in.f_local_or_uv;
if (in.f_rotation != 0.0)
{
float2 param_11 = p_local_1;
float param_12 = in.f_rotation;
p_local_1 = apply_rotation(param_11, param_12);
float2 param_15 = p_local_1;
float param_16 = in.f_rotation;
p_local_1 = apply_rotation(param_15, param_16);
}
float2 param_13 = p_local_1;
float2 param_14 = ab;
float _560 = sdEllipse(param_13, param_14);
d = _560;
float2 param_17 = p_local_1;
float2 param_18 = ab;
float _616 = sdEllipse(param_17, param_18);
d = _616;
if ((flags & 1u) != 0u)
{
float param_15 = d;
float param_16 = stroke_px_2;
d = sdf_stroke(param_15, param_16);
float param_19 = d;
float param_20 = stroke_px_2;
d = sdf_stroke(param_19, param_20);
}
}
else
@@ -220,10 +240,10 @@ fragment main0_out main0(main0_in in [[stage_in]], texture2d<float> tex [[textur
float2 b_1 = in.f_params.zw;
float width = in.f_params2.x;
soft = fast::max(in.f_params2.y, 1.0);
float2 param_17 = in.f_local_or_uv;
float2 param_18 = a;
float2 param_19 = b_1;
d = sdSegment(param_17, param_18, param_19) - (width * 0.5);
float2 param_21 = in.f_local_or_uv;
float2 param_22 = a;
float2 param_23 = b_1;
d = sdSegment(param_21, param_22, param_23) - (width * 0.5);
}
else
{
@@ -243,16 +263,16 @@ fragment main0_out main0(main0_in in [[stage_in]], texture2d<float> tex [[textur
}
float ang_start = mod(start_rad, 6.283185482025146484375);
float ang_end = mod(end_rad, 6.283185482025146484375);
float _654;
float _710;
if (ang_end > ang_start)
{
_654 = float((angle >= ang_start) && (angle <= ang_end));
_710 = float((angle >= ang_start) && (angle <= ang_end));
}
else
{
_654 = float((angle >= ang_start) || (angle <= ang_end));
_710 = float((angle >= ang_start) || (angle <= ang_end));
}
float in_arc = _654;
float in_arc = _710;
if (abs(ang_end - ang_start) >= 6.282185077667236328125)
{
in_arc = 1.0;
@@ -277,9 +297,9 @@ fragment main0_out main0(main0_in in [[stage_in]], texture2d<float> tex [[textur
d = (length(p) * cos(bn)) - radius_1;
if ((flags & 1u) != 0u)
{
float param_20 = d;
float param_21 = stroke_px_3;
d = sdf_stroke(param_20, param_21);
float param_24 = d;
float param_25 = stroke_px_3;
d = sdf_stroke(param_24, param_25);
}
}
}
@@ -287,10 +307,9 @@ fragment main0_out main0(main0_in in [[stage_in]], texture2d<float> tex [[textur
}
}
}
float param_22 = d;
float param_23 = soft;
float alpha = sdf_alpha(param_22, param_23);
out.out_color = float4(in.f_color.xyz, in.f_color.w * alpha);
float param_26 = d;
float param_27 = soft;
float alpha_1 = sdf_alpha(param_26, param_27);
out.out_color = float4(in.f_color.xyz, in.f_color.w * alpha_1);
return out;
}

BIN
draw/shaders/generated/base_2d.frag.spv
View File

Binary file not shown.

23
draw/shaders/generated/base_2d.vert.metal
View File

@@ -19,6 +19,7 @@ struct Primitive
float _pad;
float4 params;
float4 params2;
float4 uv_rect;
};
struct Primitive_1
@@ -30,6 +31,7 @@ struct Primitive_1
float _pad;
float4 params;
float4 params2;
float4 uv_rect;
};
struct Primitives
@@ -45,6 +47,7 @@ struct main0_out
float4 f_params2 [[user(locn3)]];
uint f_kind_flags [[user(locn4)]];
float f_rotation [[user(locn5)]];
float4 f_uv_rect [[user(locn6)]];
float4 gl_Position [[position]];
};
@@ -55,7 +58,7 @@ struct main0_in
float4 v_color [[attribute(2)]];
};
vertex main0_out main0(main0_in in [[stage_in]], constant Uniforms& _12 [[buffer(0)]], const device Primitives& _72 [[buffer(1)]], uint gl_InstanceIndex [[instance_id]])
vertex main0_out main0(main0_in in [[stage_in]], constant Uniforms& _12 [[buffer(0)]], const device Primitives& _74 [[buffer(1)]], uint gl_InstanceIndex [[instance_id]])
{
main0_out out = {};
if (_12.mode == 0u)
@@ -66,18 +69,20 @@ vertex main0_out main0(main0_in in [[stage_in]], constant Uniforms& _12 [[buffer
out.f_params2 = float4(0.0);
out.f_kind_flags = 0u;
out.f_rotation = 0.0;
out.f_uv_rect = float4(0.0, 0.0, 1.0, 1.0);
out.gl_Position = _12.projection * float4(in.v_position * _12.dpi_scale, 0.0, 1.0);
}
else
{
Primitive p;
p.bounds = _72.primitives[int(gl_InstanceIndex)].bounds;
p.color = _72.primitives[int(gl_InstanceIndex)].color;
p.kind_flags = _72.primitives[int(gl_InstanceIndex)].kind_flags;
p.rotation = _72.primitives[int(gl_InstanceIndex)].rotation;
p._pad = _72.primitives[int(gl_InstanceIndex)]._pad;
p.params = _72.primitives[int(gl_InstanceIndex)].params;
p.params2 = _72.primitives[int(gl_InstanceIndex)].params2;
p.bounds = _74.primitives[int(gl_InstanceIndex)].bounds;
p.color = _74.primitives[int(gl_InstanceIndex)].color;
p.kind_flags = _74.primitives[int(gl_InstanceIndex)].kind_flags;
p.rotation = _74.primitives[int(gl_InstanceIndex)].rotation;
p._pad = _74.primitives[int(gl_InstanceIndex)]._pad;
p.params = _74.primitives[int(gl_InstanceIndex)].params;
p.params2 = _74.primitives[int(gl_InstanceIndex)].params2;
p.uv_rect = _74.primitives[int(gl_InstanceIndex)].uv_rect;
float2 corner = in.v_position;
float2 world_pos = mix(p.bounds.xy, p.bounds.zw, corner);
float2 center = (p.bounds.xy + p.bounds.zw) * 0.5;
@@ -87,8 +92,8 @@ vertex main0_out main0(main0_in in [[stage_in]], constant Uniforms& _12 [[buffer
out.f_params2 = p.params2;
out.f_kind_flags = p.kind_flags;
out.f_rotation = p.rotation;
out.f_uv_rect = p.uv_rect;
out.gl_Position = _12.projection * float4(world_pos * _12.dpi_scale, 0.0, 1.0);
}
return out;
}

BIN
draw/shaders/generated/base_2d.vert.spv
View File

Binary file not shown.

18
draw/shaders/source/base_2d.frag
View File

@@ -7,6 +7,7 @@ layout(location = 2) in vec4 f_params;
layout(location = 3) in vec4 f_params2;
layout(location = 4) flat in uint f_kind_flags;
layout(location = 5) flat in float f_rotation;
layout(location = 6) flat in vec4 f_uv_rect;
// --- Output ---
layout(location = 0) out vec4 out_color;
@@ -130,6 +131,23 @@ void main() {
d = sdRoundedBox(p_local, b, r);
if ((flags & 1u) != 0u) d = sdf_stroke(d, stroke_px);
// Texture sampling for textured SDF primitives
vec4 shape_color = f_color;
if ((flags & 2u) != 0u) {
// Compute UV from local position and half_size
vec2 p_for_uv = f_local_or_uv;
if (f_rotation != 0.0) {
p_for_uv = apply_rotation(p_for_uv, f_rotation);
}
vec2 local_uv = p_for_uv / b * 0.5 + 0.5;
vec2 uv = mix(f_uv_rect.xy, f_uv_rect.zw, local_uv);
shape_color *= texture(tex, uv);
}
float alpha = sdf_alpha(d, soft);
out_color = vec4(shape_color.rgb, shape_color.a * alpha);
return;
}
else if (kind == 2u) {
// Circle — rotationally symmetric, no rotation needed

4
draw/shaders/source/base_2d.vert
View File

@@ -12,6 +12,7 @@ layout(location = 2) out vec4 f_params;
layout(location = 3) out vec4 f_params2;
layout(location = 4) flat out uint f_kind_flags;
layout(location = 5) flat out float f_rotation;
layout(location = 6) flat out vec4 f_uv_rect;
// ---------- Uniforms (single block — avoids spirv-cross reordering on Metal) ----------
layout(set = 1, binding = 0) uniform Uniforms {
@@ -29,6 +30,7 @@ struct Primitive {
float _pad; // 28-31: alignment padding
vec4 params; // 32-47: shape params part 1
vec4 params2; // 48-63: shape params part 2
vec4 uv_rect; // 64-79: u_min, v_min, u_max, v_max
};
layout(std430, set = 0, binding = 0) readonly buffer Primitives {
@@ -45,6 +47,7 @@ void main() {
f_params2 = vec4(0.0);
f_kind_flags = 0u;
f_rotation = 0.0;
f_uv_rect = vec4(0.0, 0.0, 1.0, 1.0);
gl_Position = projection * vec4(v_position * dpi_scale, 0.0, 1.0);
} else {
@@ -61,6 +64,7 @@ void main() {
f_params2 = p.params2;
f_kind_flags = p.kind_flags;
f_rotation = p.rotation;
f_uv_rect = p.uv_rect;
gl_Position = projection * vec4(world_pos * dpi_scale, 0.0, 1.0);
}

164
draw/shapes.odin
View File

@@ -68,6 +68,19 @@ emit_rectangle :: proc(x, y, width, height: f32, color: Color, vertices: []Verte
vertices[offset + 5] = solid_vertex({x, y + height}, color)
}
@(private = "file")
prepare_sdf_primitive_textured :: proc(
layer: ^Layer,
prim: Primitive,
texture_id: Texture_Id,
sampler: Sampler_Preset,
) {
offset := u32(len(GLOB.tmp_primitives))
append(&GLOB.tmp_primitives, prim)
scissor := &GLOB.scissors[layer.scissor_start + layer.scissor_len - 1]
append_or_extend_sub_batch(scissor, layer, .SDF, offset, 1, texture_id, sampler)
}
// ----- Drawing functions ----
pixel :: proc(layer: ^Layer, pos: [2]f32, color: Color) {
@@ -83,6 +96,7 @@ rectangle_gradient :: proc(
temp_allocator := context.temp_allocator,
) {
vertices := make([]Vertex, 6, temp_allocator)
defer delete(vertices, temp_allocator)
corner_top_left := [2]f32{rect.x, rect.y}
corner_top_right := [2]f32{rect.x + rect.width, rect.y}
@@ -115,6 +129,7 @@ circle_sector :: proc(
vertex_count := segment_count * 3
vertices := make([]Vertex, vertex_count, temp_allocator)
defer delete(vertices, temp_allocator)
start_radians := math.to_radians(start_angle)
end_radians := math.to_radians(end_angle)
@@ -167,6 +182,7 @@ circle_gradient :: proc(
vertex_count := segment_count * 3
vertices := make([]Vertex, vertex_count, temp_allocator)
defer delete(vertices, temp_allocator)
step_angle := math.TAU / f32(segment_count)
@@ -238,6 +254,7 @@ triangle_lines :: proc(
temp_allocator := context.temp_allocator,
) {
vertices := make([]Vertex, 18, temp_allocator)
defer delete(vertices, temp_allocator)
write_offset := 0
if !needs_transform(origin, rotation) {
@@ -273,6 +290,7 @@ triangle_fan :: proc(
triangle_count := len(points) - 2
vertex_count := triangle_count * 3
vertices := make([]Vertex, vertex_count, temp_allocator)
defer delete(vertices, temp_allocator)
if !needs_transform(origin, rotation) {
for i in 1 ..< len(points) - 1 {
@@ -312,6 +330,7 @@ triangle_strip :: proc(
triangle_count := len(points) - 2
vertex_count := triangle_count * 3
vertices := make([]Vertex, vertex_count, temp_allocator)
defer delete(vertices, temp_allocator)
if !needs_transform(origin, rotation) {
for i in 0 ..< triangle_count {
@@ -352,17 +371,20 @@ triangle_strip :: proc(
// ----- SDF drawing functions ----
// Compute new center position after rotating a center-parametrized shape
// around a pivot point. The pivot is at (center + origin) in world space.
// Compute the visual center of a center-parametrized shape after applying
// Convention B origin semantics: `center` is where the origin-point lands in
// world space; the visual center is offset by -origin and then rotated around
// the landing point.
// visual_center = center + R(θ) · (-origin)
// When θ=0: visual_center = center - origin (pure positioning shift).
// When origin={0,0}: visual_center = center (no change).
@(private = "file")
compute_pivot_center :: proc(center: [2]f32, origin: [2]f32, rotation_deg: f32) -> [2]f32 {
if origin == {0, 0} do return center
theta := math.to_radians(rotation_deg)
cos_angle, sin_angle := math.cos(theta), math.sin(theta)
// pivot = center + origin; new_center = pivot + R(θ) * (center - pivot)
return(
center +
origin +
{cos_angle * (-origin.x) - sin_angle * (-origin.y), sin_angle * (-origin.x) + cos_angle * (-origin.y)} \
)
}
@@ -378,6 +400,13 @@ rotated_aabb_half_extents :: proc(half_width, half_height, rotation_radians: f32
// Draw a filled rectangle via SDF (analytical anti-aliasing at all orientations).
// `roundness` is a 0–1 fraction controlling uniform corner rounding — 0 is sharp, 1 is fully rounded.
// For per-corner pixel-precise rounding, use `rectangle_corners` instead.
//
// Origin semantics:
// `origin` is a local offset from the rect's top-left corner that selects both the positioning
// anchor and the rotation pivot. `rect.x, rect.y` specifies where that anchor point lands in
// world space. When `origin = {0, 0}` (default), `rect.x, rect.y` is the top-left corner.
// When `origin = center_of_rectangle(rect)`, `rect.x, rect.y` is the visual center.
// Rotation always occurs around the anchor point.
rectangle :: proc(
layer: ^Layer,
rect: Rectangle,
@@ -394,6 +423,7 @@ rectangle :: proc(
// Draw a stroked rectangle via SDF (analytical anti-aliasing at all orientations).
// `roundness` is a 0–1 fraction controlling uniform corner rounding — 0 is sharp, 1 is fully rounded.
// For per-corner pixel-precise rounding, use `rectangle_corners_lines` instead.
// Origin semantics: see `rectangle`.
rectangle_lines :: proc(
layer: ^Layer,
rect: Rectangle,
@@ -409,6 +439,7 @@ rectangle_lines :: proc(
}
// Draw a rectangle with per-corner rounding radii via SDF.
// Origin semantics: see `rectangle`.
rectangle_corners :: proc(
layer: ^Layer,
rect: Rectangle,
@@ -430,12 +461,12 @@ rectangle_corners :: proc(
half_width := rect.width * 0.5
half_height := rect.height * 0.5
rotation_radians: f32 = 0
center_x := rect.x + half_width
center_y := rect.y + half_height
center_x := rect.x + half_width - origin.x
center_y := rect.y + half_height - origin.y
if needs_transform(origin, rotation) {
rotation_radians = math.to_radians(rotation)
transform := build_pivot_rotation({rect.x, rect.y}, origin, rotation)
transform := build_pivot_rotation({rect.x + origin.x, rect.y + origin.y}, origin, rotation)
new_center := apply_transform(transform, {half_width, half_height})
center_x = new_center.x
center_y = new_center.y
@@ -474,6 +505,7 @@ rectangle_corners :: proc(
}
// Draw a stroked rectangle with per-corner rounding radii via SDF.
// Origin semantics: see `rectangle`.
rectangle_corners_lines :: proc(
layer: ^Layer,
rect: Rectangle,
@@ -496,12 +528,12 @@ rectangle_corners_lines :: proc(
half_width := rect.width * 0.5
half_height := rect.height * 0.5
rotation_radians: f32 = 0
center_x := rect.x + half_width
center_y := rect.y + half_height
center_x := rect.x + half_width - origin.x
center_y := rect.y + half_height - origin.y
if needs_transform(origin, rotation) {
rotation_radians = math.to_radians(rotation)
transform := build_pivot_rotation({rect.x, rect.y}, origin, rotation)
transform := build_pivot_rotation({rect.x + origin.x, rect.y + origin.y}, origin, rotation)
new_center := apply_transform(transform, {half_width, half_height})
center_x = new_center.x
center_y = new_center.y
@@ -539,7 +571,114 @@ rectangle_corners_lines :: proc(
prepare_sdf_primitive(layer, prim)
}
// Draw a rectangle with a texture fill via SDF. Supports rounded corners via `roundness`,
// rotation, and analytical anti-aliasing on the shape silhouette.
// Origin semantics: see `rectangle`.
rectangle_texture :: proc(
layer: ^Layer,
rect: Rectangle,
id: Texture_Id,
tint: Color = WHITE,
uv_rect: Rectangle = {0, 0, 1, 1},
sampler: Sampler_Preset = .Linear_Clamp,
roundness: f32 = 0,
origin: [2]f32 = {0, 0},
rotation: f32 = 0,
soft_px: f32 = 1.0,
) {
cr := min(rect.width, rect.height) * clamp(roundness, 0, 1) * 0.5
rectangle_texture_corners(
layer,
rect,
{cr, cr, cr, cr},
id,
tint,
uv_rect,
sampler,
origin,
rotation,
soft_px,
)
}
// Draw a rectangle with a texture fill and per-corner rounding radii via SDF.
// Origin semantics: see `rectangle`.
rectangle_texture_corners :: proc(
layer: ^Layer,
rect: Rectangle,
radii: [4]f32,
id: Texture_Id,
tint: Color = WHITE,
uv_rect: Rectangle = {0, 0, 1, 1},
sampler: Sampler_Preset = .Linear_Clamp,
origin: [2]f32 = {0, 0},
rotation: f32 = 0,
soft_px: f32 = 1.0,
) {
max_radius := min(rect.width, rect.height) * 0.5
top_left := clamp(radii[0], 0, max_radius)
top_right := clamp(radii[1], 0, max_radius)
bottom_right := clamp(radii[2], 0, max_radius)
bottom_left := clamp(radii[3], 0, max_radius)
padding := soft_px / GLOB.dpi_scaling
dpi_scale := GLOB.dpi_scaling
half_width := rect.width * 0.5
half_height := rect.height * 0.5
rotation_radians: f32 = 0
center_x := rect.x + half_width - origin.x
center_y := rect.y + half_height - origin.y
if needs_transform(origin, rotation) {
rotation_radians = math.to_radians(rotation)
transform := build_pivot_rotation({rect.x + origin.x, rect.y + origin.y}, origin, rotation)
new_center := apply_transform(transform, {half_width, half_height})
center_x = new_center.x
center_y = new_center.y
}
bounds_half_width, bounds_half_height := half_width, half_height
if rotation_radians != 0 {
expanded := rotated_aabb_half_extents(half_width, half_height, rotation_radians)
bounds_half_width = expanded.x
bounds_half_height = expanded.y
}
prim := Primitive {
bounds = {
center_x - bounds_half_width - padding,
center_y - bounds_half_height - padding,
center_x + bounds_half_width + padding,
center_y + bounds_half_height + padding,
},
color = tint,
kind_flags = pack_kind_flags(.RRect, {.Textured}),
rotation = rotation_radians,
uv_rect = {uv_rect.x, uv_rect.y, uv_rect.width, uv_rect.height},
}
prim.params.rrect = RRect_Params {
half_size = {half_width * dpi_scale, half_height * dpi_scale},
radii = {
top_right * dpi_scale,
bottom_right * dpi_scale,
top_left * dpi_scale,
bottom_left * dpi_scale,
},
soft_px = soft_px,
stroke_px = 0,
}
prepare_sdf_primitive_textured(layer, prim, id, sampler)
}
// Draw a filled circle via SDF.
//
// Origin semantics (Convention B):
// `origin` is a local offset from the shape's center that selects both the positioning anchor
// and the rotation pivot. The `center` parameter specifies where that anchor point lands in
// world space. When `origin = {0, 0}` (default), `center` is the visual center.
// When `origin = {r, 0}`, the point `r` pixels to the right of the shape center lands at
// `center`, shifting the shape left by `r`.
circle :: proc(
layer: ^Layer,
center: [2]f32,
@@ -576,6 +715,7 @@ circle :: proc(
}
// Draw a stroked circle via SDF.
// Origin semantics: see `circle`.
circle_lines :: proc(
layer: ^Layer,
center: [2]f32,
@@ -613,6 +753,7 @@ circle_lines :: proc(
}
// Draw a filled ellipse via SDF.
// Origin semantics: see `circle`.
ellipse :: proc(
layer: ^Layer,
center: [2]f32,
@@ -659,6 +800,7 @@ ellipse :: proc(
}
// Draw a stroked ellipse via SDF.
// Origin semantics: see `circle`.
ellipse_lines :: proc(
layer: ^Layer,
center: [2]f32,
@@ -709,6 +851,7 @@ ellipse_lines :: proc(
}
// Draw a filled ring arc via SDF.
// Origin semantics: see `circle`.
ring :: proc(
layer: ^Layer,
center: [2]f32,
@@ -751,6 +894,7 @@ ring :: proc(
}
// Draw stroked ring arc outlines via SDF.
// Origin semantics: see `circle`.
ring_lines :: proc(
layer: ^Layer,
center: [2]f32,

6
draw/text.odin
View File

@@ -139,6 +139,7 @@ text :: proc(
temp_allocator := context.temp_allocator,
) {
c_str := strings.clone_to_cstring(text_string, temp_allocator)
defer delete(c_str, temp_allocator)
sdl_text: ^sdl_ttf.Text
cached := false
@@ -180,6 +181,7 @@ measure_text :: proc(
allocator := context.temp_allocator,
) -> [2]f32 {
c_str := strings.clone_to_cstring(text_string, allocator)
defer delete(c_str, allocator)
width, height: c.int
if !sdl_ttf.GetStringSize(get_font(font_id, font_size), c_str, 0, &width, &height) {
log.panicf("Failed to measure text: %s", sdl.GetError())
@@ -244,7 +246,7 @@ bottom_right_of_text :: proc(text_string: string, font_id: Font_Id, font_size: u
// After calling this, subsequent text draws with an `id` will re-create their cache entries.
clear_text_cache :: proc() {
for _, sdl_text in GLOB.text_cache.cache {
sdl_ttf.DestroyText(sdl_text)
append(&GLOB.pending_text_releases, sdl_text)
}
clear(&GLOB.text_cache.cache)
}
@@ -257,7 +259,7 @@ clear_text_cache_entry :: proc(id: u32) {
key := Cache_Key{id, .Custom}
sdl_text, ok := GLOB.text_cache.cache[key]
if ok {
sdl_ttf.DestroyText(sdl_text)
append(&GLOB.pending_text_releases, sdl_text)
delete_key(&GLOB.text_cache.cache, key)
}
}

414
draw/textures.odin Normal file
View File

@@ -0,0 +1,414 @@
package draw
import "core:log"
import "core:mem"
import sdl "vendor:sdl3"
Texture_Id :: distinct u32
INVALID_TEXTURE :: Texture_Id(0) // Slot 0 is reserved/unused
Texture_Kind :: enum u8 {
Static, // Uploaded once, never changes (QR codes, decoded PNGs, icons)
Dynamic, // Updatable via update_texture_region
Stream, // Frequent full re-uploads (video, procedural)
}
Sampler_Preset :: enum u8 {
Nearest_Clamp,
Linear_Clamp,
Nearest_Repeat,
Linear_Repeat,
}
SAMPLER_PRESET_COUNT :: 4
Fit_Mode :: enum u8 {
Stretch, // Fill rect, may distort aspect ratio (default)
Fit, // Preserve aspect, letterbox (may leave margins)
Fill, // Preserve aspect, center-crop (may crop edges)
Tile, // Repeat at native texture size
Center, // 1:1 pixel size, centered, no scaling
}
Texture_Desc :: struct {
width: u32,
height: u32,
depth_or_layers: u32,
type: sdl.GPUTextureType,
format: sdl.GPUTextureFormat,
usage: sdl.GPUTextureUsageFlags,
mip_levels: u32,
kind: Texture_Kind,
}
// Internal slot — not exported.
@(private)
Texture_Slot :: struct {
gpu_texture: ^sdl.GPUTexture,
desc: Texture_Desc,
generation: u32,
}
// State stored in GLOB
// This file references:
// GLOB.device : ^sdl.GPUDevice
// GLOB.texture_slots : [dynamic]Texture_Slot
// GLOB.texture_free_list : [dynamic]u32
// GLOB.pending_texture_releases : [dynamic]Texture_Id
// GLOB.samplers : [SAMPLER_PRESET_COUNT]^sdl.GPUSampler
Clay_Image_Data :: struct {
texture_id: Texture_Id,
fit: Fit_Mode,
tint: Color,
}
clay_image_data :: proc(id: Texture_Id, fit: Fit_Mode = .Stretch, tint: Color = WHITE) -> Clay_Image_Data {
return {texture_id = id, fit = fit, tint = tint}
}
// ---------------------------------------------------------------------------------------------------------------------
// ----- Registration -------------
// ---------------------------------------------------------------------------------------------------------------------
// Register a texture. Draw owns the GPU resource and releases it on unregister.
// `data` is tightly-packed row-major bytes matching desc.format.
// The caller may free `data` immediately after this proc returns.
@(require_results)
register_texture :: proc(desc: Texture_Desc, data: []u8) -> (id: Texture_Id, ok: bool) {
device := GLOB.device
if device == nil {
log.error("register_texture called before draw.init()")
return INVALID_TEXTURE, false
}
assert(desc.width > 0, "Texture_Desc.width must be > 0")
assert(desc.height > 0, "Texture_Desc.height must be > 0")
assert(desc.depth_or_layers > 0, "Texture_Desc.depth_or_layers must be > 0")
assert(desc.mip_levels > 0, "Texture_Desc.mip_levels must be > 0")
assert(desc.usage != {}, "Texture_Desc.usage must not be empty (e.g. {.SAMPLER})")
// Create the GPU texture
gpu_texture := sdl.CreateGPUTexture(
device,
sdl.GPUTextureCreateInfo {
type = desc.type,
format = desc.format,
usage = desc.usage,
width = desc.width,
height = desc.height,
layer_count_or_depth = desc.depth_or_layers,
num_levels = desc.mip_levels,
sample_count = ._1,
},
)
if gpu_texture == nil {
log.errorf("Failed to create GPU texture (%dx%d): %s", desc.width, desc.height, sdl.GetError())
return INVALID_TEXTURE, false
}
// Upload pixel data via a transfer buffer
if len(data) > 0 {
data_size := u32(len(data))
transfer := sdl.CreateGPUTransferBuffer(
device,
sdl.GPUTransferBufferCreateInfo{usage = .UPLOAD, size = data_size},
)
if transfer == nil {
log.errorf("Failed to create texture transfer buffer: %s", sdl.GetError())
sdl.ReleaseGPUTexture(device, gpu_texture)
return INVALID_TEXTURE, false
}
defer sdl.ReleaseGPUTransferBuffer(device, transfer)
mapped := sdl.MapGPUTransferBuffer(device, transfer, false)
if mapped == nil {
log.errorf("Failed to map texture transfer buffer: %s", sdl.GetError())
sdl.ReleaseGPUTexture(device, gpu_texture)
return INVALID_TEXTURE, false
}
mem.copy(mapped, raw_data(data), int(data_size))
sdl.UnmapGPUTransferBuffer(device, transfer)
cmd_buffer := sdl.AcquireGPUCommandBuffer(device)
if cmd_buffer == nil {
log.errorf("Failed to acquire command buffer for texture upload: %s", sdl.GetError())
sdl.ReleaseGPUTexture(device, gpu_texture)
return INVALID_TEXTURE, false
}
copy_pass := sdl.BeginGPUCopyPass(cmd_buffer)
sdl.UploadToGPUTexture(
copy_pass,
sdl.GPUTextureTransferInfo{transfer_buffer = transfer},
sdl.GPUTextureRegion{texture = gpu_texture, w = desc.width, h = desc.height, d = desc.depth_or_layers},
false,
)
sdl.EndGPUCopyPass(copy_pass)
if !sdl.SubmitGPUCommandBuffer(cmd_buffer) {
log.errorf("Failed to submit texture upload: %s", sdl.GetError())
sdl.ReleaseGPUTexture(device, gpu_texture)
return INVALID_TEXTURE, false
}
}
// Allocate a slot (reuse from free list or append)
slot_index: u32
if len(GLOB.texture_free_list) > 0 {
slot_index = pop(&GLOB.texture_free_list)
GLOB.texture_slots[slot_index] = Texture_Slot {
gpu_texture = gpu_texture,
desc = desc,
generation = GLOB.texture_slots[slot_index].generation + 1,
}
} else {
slot_index = u32(len(GLOB.texture_slots))
append(&GLOB.texture_slots, Texture_Slot{gpu_texture = gpu_texture, desc = desc, generation = 1})
}
return Texture_Id(slot_index), true
}
// Queue a texture for release at the end of the current frame.
// The GPU resource is not freed immediately — see "Deferred release" in the README.
unregister_texture :: proc(id: Texture_Id) {
if id == INVALID_TEXTURE do return
append(&GLOB.pending_texture_releases, id)
}
// Re-upload a sub-region of a Dynamic texture.
update_texture_region :: proc(id: Texture_Id, region: Rectangle, data: []u8) {
if id == INVALID_TEXTURE do return
slot := &GLOB.texture_slots[u32(id)]
if slot.gpu_texture == nil do return
device := GLOB.device
data_size := u32(len(data))
if data_size == 0 do return
transfer := sdl.CreateGPUTransferBuffer(
device,
sdl.GPUTransferBufferCreateInfo{usage = .UPLOAD, size = data_size},
)
if transfer == nil {
log.errorf("Failed to create transfer buffer for texture region update: %s", sdl.GetError())
return
}
defer sdl.ReleaseGPUTransferBuffer(device, transfer)
mapped := sdl.MapGPUTransferBuffer(device, transfer, false)
if mapped == nil {
log.errorf("Failed to map transfer buffer for texture region update: %s", sdl.GetError())
return
}
mem.copy(mapped, raw_data(data), int(data_size))
sdl.UnmapGPUTransferBuffer(device, transfer)
cmd_buffer := sdl.AcquireGPUCommandBuffer(device)
if cmd_buffer == nil {
log.errorf("Failed to acquire command buffer for texture region update: %s", sdl.GetError())
return
}
copy_pass := sdl.BeginGPUCopyPass(cmd_buffer)
sdl.UploadToGPUTexture(
copy_pass,
sdl.GPUTextureTransferInfo{transfer_buffer = transfer},
sdl.GPUTextureRegion {
texture = slot.gpu_texture,
x = u32(region.x),
y = u32(region.y),
w = u32(region.width),
h = u32(region.height),
d = 1,
},
false,
)
sdl.EndGPUCopyPass(copy_pass)
if !sdl.SubmitGPUCommandBuffer(cmd_buffer) {
log.errorf("Failed to submit texture region update: %s", sdl.GetError())
}
}
// ---------------------------------------------------------------------------------------------------------------------
// ----- Helpers -------------
// ---------------------------------------------------------------------------------------------------------------------
// Compute UV rect, recommended sampler, and inner rect for a given fit mode.
// `rect` is the target drawing area; `texture_id` identifies the texture whose
// pixel dimensions are looked up via texture_size().
// For Fit mode, `inner_rect` is smaller than `rect` (centered). For all other modes, `inner_rect == rect`.
fit_params :: proc(
fit: Fit_Mode,
rect: Rectangle,
texture_id: Texture_Id,
) -> (
uv_rect: Rectangle,
sampler: Sampler_Preset,
inner_rect: Rectangle,
) {
size := texture_size(texture_id)
texture_width := f32(size.x)
texture_height := f32(size.y)
rect_width := rect.width
rect_height := rect.height
inner_rect = rect
if texture_width == 0 || texture_height == 0 || rect_width == 0 || rect_height == 0 {
return {0, 0, 1, 1}, .Linear_Clamp, inner_rect
}
texture_aspect := texture_width / texture_height
rect_aspect := rect_width / rect_height
switch fit {
case .Stretch: return {0, 0, 1, 1}, .Linear_Clamp, inner_rect
case .Fill: if texture_aspect > rect_aspect {
// Texture wider than rect — crop sides
scale := rect_aspect / texture_aspect
margin := (1 - scale) * 0.5
return {margin, 0, 1 - margin, 1}, .Linear_Clamp, inner_rect
} else {
// Texture taller than rect — crop top/bottom
scale := texture_aspect / rect_aspect
margin := (1 - scale) * 0.5
return {0, margin, 1, 1 - margin}, .Linear_Clamp, inner_rect
}
case .Fit:
// Preserve aspect, fit inside rect. Returns a shrunken inner_rect.
if texture_aspect > rect_aspect {
// Image wider — letterbox top/bottom
fit_height := rect_width / texture_aspect
padding := (rect_height - fit_height) * 0.5
inner_rect = Rectangle{rect.x, rect.y + padding, rect_width, fit_height}
} else {
// Image taller — letterbox left/right
fit_width := rect_height * texture_aspect
padding := (rect_width - fit_width) * 0.5
inner_rect = Rectangle{rect.x + padding, rect.y, fit_width, rect_height}
}
return {0, 0, 1, 1}, .Linear_Clamp, inner_rect
case .Tile:
uv_width := rect_width / texture_width
uv_height := rect_height / texture_height
return {0, 0, uv_width, uv_height}, .Linear_Repeat, inner_rect
case .Center:
u_half := rect_width / (2 * texture_width)
v_half := rect_height / (2 * texture_height)
return {0.5 - u_half, 0.5 - v_half, 0.5 + u_half, 0.5 + v_half}, .Nearest_Clamp, inner_rect
}
return {0, 0, 1, 1}, .Linear_Clamp, inner_rect
}
texture_size :: proc(id: Texture_Id) -> [2]u32 {
if id == INVALID_TEXTURE do return {0, 0}
slot := &GLOB.texture_slots[u32(id)]
return {slot.desc.width, slot.desc.height}
}
texture_format :: proc(id: Texture_Id) -> sdl.GPUTextureFormat {
if id == INVALID_TEXTURE do return .INVALID
return GLOB.texture_slots[u32(id)].desc.format
}
texture_kind :: proc(id: Texture_Id) -> Texture_Kind {
if id == INVALID_TEXTURE do return .Static
return GLOB.texture_slots[u32(id)].desc.kind
}
// Internal: get the raw GPU texture pointer for binding during draw.
@(private)
texture_gpu_handle :: proc(id: Texture_Id) -> ^sdl.GPUTexture {
if id == INVALID_TEXTURE do return nil
idx := u32(id)
if idx >= u32(len(GLOB.texture_slots)) do return nil
return GLOB.texture_slots[idx].gpu_texture
}
// Deferred release (called from draw.end / clear_global)
@(private)
process_pending_texture_releases :: proc() {
device := GLOB.device
for id in GLOB.pending_texture_releases {
idx := u32(id)
if idx >= u32(len(GLOB.texture_slots)) do continue
slot := &GLOB.texture_slots[idx]
if slot.gpu_texture != nil {
sdl.ReleaseGPUTexture(device, slot.gpu_texture)
slot.gpu_texture = nil
}
slot.generation += 1
append(&GLOB.texture_free_list, idx)
}
clear(&GLOB.pending_texture_releases)
}
@(private)
get_sampler :: proc(preset: Sampler_Preset) -> ^sdl.GPUSampler {
idx := int(preset)
if GLOB.samplers[idx] != nil do return GLOB.samplers[idx]
// Lazily create
min_filter, mag_filter: sdl.GPUFilter
address_mode: sdl.GPUSamplerAddressMode
switch preset {
case .Nearest_Clamp:
min_filter = .NEAREST; mag_filter = .NEAREST; address_mode = .CLAMP_TO_EDGE
case .Linear_Clamp:
min_filter = .LINEAR; mag_filter = .LINEAR; address_mode = .CLAMP_TO_EDGE
case .Nearest_Repeat:
min_filter = .NEAREST; mag_filter = .NEAREST; address_mode = .REPEAT
case .Linear_Repeat:
min_filter = .LINEAR; mag_filter = .LINEAR; address_mode = .REPEAT
}
sampler := sdl.CreateGPUSampler(
GLOB.device,
sdl.GPUSamplerCreateInfo {
min_filter = min_filter,
mag_filter = mag_filter,
mipmap_mode = .LINEAR,
address_mode_u = address_mode,
address_mode_v = address_mode,
address_mode_w = address_mode,
},
)
if sampler == nil {
log.errorf("Failed to create sampler preset %v: %s", preset, sdl.GetError())
return GLOB.pipeline_2d_base.sampler // fallback to existing default sampler
}
GLOB.samplers[idx] = sampler
return sampler
}
// Internal: destroy all sampler pool entries. Called from draw.destroy().
@(private)
destroy_sampler_pool :: proc() {
device := GLOB.device
for &s in GLOB.samplers {
if s != nil {
sdl.ReleaseGPUSampler(device, s)
s = nil
}
}
}
// Internal: destroy all registered textures. Called from draw.destroy().
@(private)
destroy_all_textures :: proc() {
device := GLOB.device
for &slot in GLOB.texture_slots {
if slot.gpu_texture != nil {
sdl.ReleaseGPUTexture(device, slot.gpu_texture)
slot.gpu_texture = nil
}
}
delete(GLOB.texture_slots)
delete(GLOB.texture_free_list)
delete(GLOB.pending_texture_releases)
}