1 files changed, 27 insertions, 3 deletions
diff --git a/libvo/d3d_shader_yuv.hlsl b/libvo/d3d_shader_yuv.hlsl
index 9d46e536fc..b17e257210 100644
--- a/libvo/d3d_shader_yuv.hlsl
+++ b/libvo/d3d_shader_yuv.hlsl
@@ -1,20 +1,44 @@
 // Compile with:
 // fxc.exe /Tps_2_0 /Fhd3d_shader_yuv.h d3d_shader_yuv.hlsl /Vnd3d_shader_yuv
+// fxc.exe /Tps_2_0 /Fhd3d_shader_yuv_2ch.h d3d_shader_yuv.hlsl /Vnd3d_shader_yuv_2ch /DUSE_2CH=1
+
+// Be careful with this shader. You can't use constant slots, since we don't
+// load the shader with D3DX. All uniform variables are mapped to hardcoded
+// constant slots.
 
 sampler2D tex0 : register(s0);
 sampler2D tex1 : register(s1);
 sampler2D tex2 : register(s2);
 
 uniform float4x4 colormatrix : register(c0);
+uniform float2 depth : register(c5);
+
+#ifdef USE_2CH
+
+float1 sample(sampler2D tex, float2 t)
+{
+    // Sample from A8L8 format as if we sampled a single value from L16.
+    // We compute the 2 channel values back into one.
+    return dot(tex2D(tex, t).xw, depth);
+}
+
+#else
+
+float1 sample(sampler2D tex, float2 t)
+{
+    return tex2D(tex, t).x;
+}
+
+#endif
 
 float4 main(float2 t0 : TEXCOORD0,
             float2 t1 : TEXCOORD1,
             float2 t2 : TEXCOORD2)
             : COLOR
 {
-    float4 c = float4(tex2D(tex0, t0).x,
-                      tex2D(tex1, t1).x,
-                      tex2D(tex2, t2).x,
+    float4 c = float4(sample(tex0, t0),
+                      sample(tex1, t1),
+                      sample(tex2, t2),
                       1);
     return mul(c, colormatrix);
 }