Moved Shaders src to CodeWalker.Shaders

CodeWalker.Shaders/PPReduceTo0DCS.hlsl

@@ -0,0 +1,54 @@
+StructuredBuffer<float> Input : register( t0 );
+RWStructuredBuffer<float> Result : register( u0 );
+
+cbuffer cbCS : register( b0 )
+{
+    uint4    g_param;   // g_param.x is the actual elements contained in Input
+                        // g_param.y is the x dimension of the Dispatch call
+};
+
+#define groupthreads 128
+groupshared float accum[groupthreads];
+
+[numthreads(groupthreads,1,1)]
+void main( uint3 Gid : SV_GroupID, uint3 DTid : SV_DispatchThreadID, uint3 GTid : SV_GroupThreadID, uint GI : SV_GroupIndex )
+{
+    if ( DTid.x < g_param.x )
+        accum[GI] = Input[DTid.x];
+    else
+        accum[GI] = 0;
+
+    // Parallel reduction algorithm follows 
+    GroupMemoryBarrierWithGroupSync();
+    if ( GI < 64 )
+        accum[GI] += accum[64+GI];  
+
+    GroupMemoryBarrierWithGroupSync();
+    if ( GI < 32 )    
+        accum[GI] += accum[32+GI];
+
+    GroupMemoryBarrierWithGroupSync();
+    if ( GI < 16 )
+        accum[GI] += accum[16+GI];
+
+    GroupMemoryBarrierWithGroupSync();
+    if ( GI < 8 ) 
+        accum[GI] += accum[8+GI];
+
+    GroupMemoryBarrierWithGroupSync();
+    if ( GI < 4 )
+        accum[GI] += accum[4+GI];
+
+    GroupMemoryBarrierWithGroupSync();
+    if ( GI < 2 )
+        accum[GI] += accum[2+GI];
+
+    GroupMemoryBarrierWithGroupSync();
+    if ( GI < 1 )
+        accum[GI] += accum[1+GI];
+
+    if ( GI == 0 )
+    {        
+        Result[Gid.x] = accum[0];
+    }
+}