Separate dither matrix per color channel

--HG--
branch : develop

code/nel/tools/3d/tga_2_dds/tga2dds.cpp

@@ -359,13 +359,27 @@ void dividSize (CBitmap &bitmap)
 	}
 }
 
-const int bayerDiv8[4][4] = {
+const int bayerDiv8R[4][4] = {
+	7, 3, 6, 2,
+	1, 5, 0, 4,
+	6, 2, 7, 3,
+	0, 4, 1, 5,
+};
+
+const int bayerDiv8G[4][4] = {
 	0, 4, 1, 5,
 	6, 2, 7, 3,
 	1, 5, 0, 4,
 	7, 3, 6, 2,
 };
 
+const int bayerDiv8B[4][4] = {
+	5, 1, 4, 0, 
+	3, 7, 2, 6, 
+	4, 0, 5, 1, 
+	2, 6, 3, 7, 
+};
+
 // ***************************************************************************
 int main(int argc, char **argv)
 {
@@ -618,9 +632,9 @@ int main(int argc, char **argv)
 		for (uint32 i = 0; i < rgba.size(); i += 4)
 		{
 			NLMISC::CRGBA &c = reinterpret_cast<NLMISC::CRGBA &>(rgba[i]);
-			c.R = (uint8)std::min(255, (int)c.R + bayerDiv8[x % 4][y % 4]);
+			c.R = (uint8)std::min(255, (int)c.R + bayerDiv8R[x % 4][y % 4]);
-			c.G = (uint8)std::min(255, (int)c.G + bayerDiv8[x % 4][y % 4]);
+			c.G = (uint8)std::min(255, (int)c.G + bayerDiv8G[x % 4][y % 4]);
-			c.B = (uint8)std::min(255, (int)c.B + bayerDiv8[x % 4][y % 4]);
+			c.B = (uint8)std::min(255, (int)c.B + bayerDiv8B[x % 4][y % 4]);
 			++x;
 			x %= w;
 			if (x == 0)