Backdrop Path + Cybersteel (#23)

Co-authored-by: Zachary Levy <zachary@sunforge.is> Reviewed-on: #23
2026-05-01 05:43:10 +00:00
parent e36229a3ef
commit 5317b8f142
66 changed files with 5806 additions and 2427 deletions
@@ -0,0 +1,118 @@
+#pragma clang diagnostic ignored "-Wmissing-prototypes"
+
+#include <metal_stdlib>
+#include <simd/simd.h>
+
+using namespace metal;
+
+struct Uniforms
+{
+    float2 inv_working_size;
+    uint pair_count;
+    uint mode;
+    float2 direction;
+    float inv_downsample_factor;
+    float _pad0;
+    float4 kernel0[32];
+};
+
+struct main0_out
+{
+    float4 out_color [[color(0)]];
+};
+
+struct main0_in
+{
+    float2 p_local [[user(locn0)]];
+    float4 f_color [[user(locn1)]];
+    float2 f_half_size [[user(locn2), flat]];
+    float4 f_radii [[user(locn3), flat]];
+    float f_half_feather [[user(locn4), flat]];
+};
+
+static inline __attribute__((always_inline))
+float3 blur_sample(thread const float2& uv, constant Uniforms& _108, texture2d<float> blur_input_tex, sampler blur_input_texSmplr)
+{
+    float3 color = blur_input_tex.sample(blur_input_texSmplr, uv).xyz * _108.kernel0[0].x;
+    float2 axis_step = _108.direction * _108.inv_working_size;
+    for (uint i = 1u; i < _108.pair_count; i++)
+    {
+        float w = _108.kernel0[i].x;
+        float off = _108.kernel0[i].y;
+        float2 step_uv = axis_step * off;
+        color += (blur_input_tex.sample(blur_input_texSmplr, (uv - step_uv)).xyz * w);
+        color += (blur_input_tex.sample(blur_input_texSmplr, (uv + step_uv)).xyz * w);
+    }
+    return color;
+}
+
+static inline __attribute__((always_inline))
+float sdRoundedBox(thread const float2& p, thread const float2& b, thread const float4& r)
+{
+    float2 _36;
+    if (p.x > 0.0)
+    {
+        _36 = r.xy;
+    }
+    else
+    {
+        _36 = r.zw;
+    }
+    float2 rxy = _36;
+    float _50;
+    if (p.y > 0.0)
+    {
+        _50 = rxy.x;
+    }
+    else
+    {
+        _50 = rxy.y;
+    }
+    float rr = _50;
+    float2 q = abs(p) - b;
+    if (rr == 0.0)
+    {
+        return fast::max(q.x, q.y);
+    }
+    q += float2(rr);
+    return (fast::min(fast::max(q.x, q.y), 0.0) + length(fast::max(q, float2(0.0)))) - rr;
+}
+
+static inline __attribute__((always_inline))
+float sdf_alpha(thread const float& d, thread const float& h)
+{
+    return 1.0 - smoothstep(-h, h, d);
+}
+
+fragment main0_out main0(main0_in in [[stage_in]], constant Uniforms& _108 [[buffer(0)]], texture2d<float> blur_input_tex [[texture(0)]], sampler blur_input_texSmplr [[sampler(0)]], float4 gl_FragCoord [[position]])
+{
+    main0_out out = {};
+    if (_108.mode == 0u)
+    {
+        float2 uv = gl_FragCoord.xy * _108.inv_working_size;
+        float2 param = uv;
+        float3 color = blur_sample(param, _108, blur_input_tex, blur_input_texSmplr);
+        out.out_color = float4(color, 1.0);
+        return out;
+    }
+    float2 param_1 = in.p_local;
+    float2 param_2 = in.f_half_size;
+    float4 param_3 = in.f_radii;
+    float d = sdRoundedBox(param_1, param_2, param_3);
+    if (d > in.f_half_feather)
+    {
+        discard_fragment();
+    }
+    float grad_magnitude = fast::max(fwidth(d), 9.9999999747524270787835121154785e-07);
+    float d_n = d / grad_magnitude;
+    float h_n = in.f_half_feather / grad_magnitude;
+    float2 uv_1 = (gl_FragCoord.xy * _108.inv_downsample_factor) * _108.inv_working_size;
+    float3 color_1 = blur_input_tex.sample(blur_input_texSmplr, uv_1).xyz;
+    float3 tinted = mix(color_1, color_1 * in.f_color.xyz, float3(in.f_color.w));
+    float param_4 = d_n;
+    float param_5 = h_n;
+    float coverage = sdf_alpha(param_4, param_5);
+    out.out_color = float4(tinted * coverage, coverage);
+    return out;
+}
+