Repo created

libs/shaders/Metal/screen_quad.metal

@@ -0,0 +1,40 @@
+#include <metal_stdlib>
+#include <simd/simd.h>
+using namespace metal;
+
+typedef struct
+{
+  float2 a_position [[attribute(0)]];
+  float2 a_texCoords [[attribute(1)]];
+} Vertex_T;
+
+typedef struct
+{
+  float4 position [[position]];
+  float2 texCoords;
+} Fragment_T;
+
+typedef struct
+{
+  float u_opacity;
+  float u_invertV;
+} Uniforms_T;
+
+vertex Fragment_T vsScreenQuad(const Vertex_T in [[stage_in]],
+                               constant Uniforms_T & uniforms [[buffer(1)]])
+{
+  Fragment_T out;
+  out.position = float4(in.a_position, 0.0, 1.0);
+  out.texCoords = mix(in.a_texCoords, float2(in.a_texCoords.x, 1.0 - in.a_texCoords.y), uniforms.u_invertV);
+  return out;
+}
+
+fragment float4 fsScreenQuad(const Fragment_T in [[stage_in]],
+                             constant Uniforms_T & uniforms [[buffer(0)]],
+                             texture2d<float> u_colorTex [[texture(0)]],
+                             sampler u_colorTexSampler [[sampler(0)]])
+{
+  float4 color = u_colorTex.sample(u_colorTexSampler, in.texCoords);
+  color.a *= uniforms.u_opacity;
+  return color;
+}