测试代码备份

DevelopmentPods/FUSBDAlphaPlayer/FUSBDAlphaPlayer/Classes/Render/bd_shaders.metal

@@ -29,20 +29,27 @@ fragment float4 samplingShader(RasterizerData input [[stage_in]],
                texture2d<float> textureUV [[ texture(BDAlphaPlayerFragmentTextureIndexTextureUV) ]],
                constant BDAlphaPlayerConvertMatrix *convertMatrix [[ buffer(BDAlphaPlayerFragmentInputIndexMatrix) ]])
 {
-    constexpr sampler textureSampler (mag_filter::linear, min_filter::linear);
+    constexpr sampler textureSamplerLinear (mag_filter::linear, min_filter::linear);
+    constexpr sampler textureSamplerNearest (mag_filter::nearest, min_filter::nearest);
 
-    float tcx = input.textureCoordinate.x / 2 + 0.5;
+    // 主体颜色采样（右半边）
+    float2 colorTexCoord = float2(input.textureCoordinate.x / 2 + 0.5, input.textureCoordinate.y);
+    float yColor = textureY.sample(textureSamplerLinear, colorTexCoord).r;
+    float2 uvColor = textureUV.sample(textureSamplerLinear, colorTexCoord).rg;
 
-    float3 yuv = float3(textureY.sample(textureSampler, float2(tcx, input.textureCoordinate.y)).r,
-                          textureUV.sample(textureSampler, float2(tcx, input.textureCoordinate.y)).rg);
+    float3 yuvColor = float3(yColor, uvColor);
+    float3 rgb = convertMatrix->matrix * (yuvColor + convertMatrix->offset);
 
-    float3 rgb = convertMatrix->matrix * (yuv + convertMatrix->offset);
+    // Alpha 采样（左半边）
+    float2 alphaTexCoord = float2(input.textureCoordinate.x / 2, input.textureCoordinate.y);
+    float yAlpha = textureY.sample(textureSamplerNearest, alphaTexCoord).r;
 
-    float3 alpha = float3(textureY.sample(textureSampler, float2(input.textureCoordinate.x / 2, input.textureCoordinate.y)).r,
-    textureUV.sample(textureSampler, float2(input.textureCoordinate.x / 2, input.textureCoordinate.y)).rg);
+    // 映射 Alpha 范围
+    #define ALPHA_MIN 0.1
+    #define ALPHA_MAX 0.9
+    float finalAlpha = saturate((yAlpha - ALPHA_MIN) / (ALPHA_MAX - ALPHA_MIN));
 
-    float3 alphargb = convertMatrix->matrix * (alpha + convertMatrix->offset);
-    return float4(rgb, alphargb.r);
+    return float4(rgb, finalAlpha);
 }