Basic texture support

draw/draw_qr/draw_qr.odin

@@ -0,0 +1,78 @@
+package draw_qr
+
+import draw ".."
+import "../../qrcode"
+
+// A registered QR code texture, ready for display via draw.rectangle_texture.
+QR :: struct {
+	texture_id: draw.Texture_Id,
+	size:       int, // modules per side (e.g. 21..177)
+}
+
+// Encode text as a QR code and register the result as an R8 texture.
+// The texture uses Nearest_Clamp sampling by default (sharp module edges).
+// Returns ok=false if encoding or registration fails.
+@(require_results)
+create_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,
+) -> (
+	qr: QR,
+	ok: bool,
+) {
+	qrcode_buf: [qrcode.BUFFER_LEN_MAX]u8
+	encode_ok := qrcode.encode(text, qrcode_buf[:], ecl, min_version, max_version, mask, boost_ecl)
+	if !encode_ok do return {}, false
+	return create(qrcode_buf[:])
+}
+
+// Register an already-encoded QR code buffer as an R8 texture.
+// qrcode_buf must be the output of qrcode.encode (byte 0 = side length, remaining = bit-packed modules).
+@(require_results)
+create :: proc(qrcode_buf: []u8) -> (qr: QR, ok: bool) {
+	size := qrcode.get_size(qrcode_buf)
+	if size == 0 do return {}, false
+
+	// Build R8 pixel buffer: 0 = light, 255 = dark
+	pixels := make([]u8, size * size, context.temp_allocator)
+	for y in 0 ..< size {
+		for x in 0 ..< size {
+			pixels[y * size + x] = 255 if qrcode.get_module(qrcode_buf, x, y) else 0
+		}
+	}
+
+	id, reg_ok := draw.register_texture(
+		draw.Texture_Desc {
+			width = u32(size),
+			height = u32(size),
+			depth_or_layers = 1,
+			type = .D2,
+			format = .R8_UNORM,
+			usage = {.SAMPLER},
+			mip_levels = 1,
+			kind = .Static,
+		},
+		pixels,
+	)
+	if !reg_ok do return {}, false
+
+	return QR{texture_id = id, size = size}, true
+}
+
+// Release the GPU texture.
+destroy :: proc(qr: ^QR) {
+	draw.unregister_texture(qr.texture_id)
+	qr.texture_id = draw.INVALID_TEXTURE
+	qr.size = 0
+}
+
+// Convenience: build a Clay_Image_Data for embedding a QR in Clay layouts.
+// Uses Nearest_Clamp sampling (set via Sampler_Preset at draw time, not here) and Fit mode
+// to preserve the QR's square aspect ratio.
+clay_image :: proc(qr: QR, tint: draw.Color = draw.WHITE) -> draw.Clay_Image_Data {
+	return draw.clay_image_data(qr.texture_id, fit = .Fit, tint = tint)
+}