Add create minimal set option.

src/nvtt/squish/colourset.cpp

@@ -28,12 +28,11 @@
 namespace squish {
 
 // @@ Add flags:
-// - FindColorMatch
-// - DXT1a
+// - MatchTransparent
 // - WeightColorByAlpha
 
 	
-ColourSet::ColourSet( u8 const* rgba, int flags )
+ColourSet::ColourSet( u8 const* rgba, int flags, bool createMinimalSet/*=false*/ )
   : m_count( 0 ), 
 	m_transparent( false )
 {
@@ -49,26 +48,11 @@ ColourSet::ColourSet( u8 const* rgba, int flags )
 		{
 			m_remap[i] = -1;
 			m_transparent = true;
-		//	continue;
+			if (createMinimalSet) continue;
 		}
 		
-#if 1
-		// normalise coordinates to [0,1]
-		float x = ( float )rgba[4*i + 2] / 255.0f;
-		float y = ( float )rgba[4*i + 1] / 255.0f;
-		float z = ( float )rgba[4*i + 0] / 255.0f;
-		
-		// ensure there is always non-zero weight even for zero alpha
-		float w = ( float )( rgba[4*i + 3] + 1 ) / 256.0f;
-
-		// add the point
-		m_points[m_count] = Vec3( x, y, z );
-		m_weights[m_count] = ( weightByAlpha ? w : 1.0f );
-		m_remap[i] = m_count;
-		
-		// advance
-		++m_count;
-#else
+		if (createMinimalSet)
+		{
 			// loop over previous points for a match
 			for( int j = 0;; ++j )
 			{
@@ -97,7 +81,8 @@ ColourSet::ColourSet( u8 const* rgba, int flags )
 				bool match = ( rgba[4*i] == rgba[4*j] )
 					&& ( rgba[4*i + 1] == rgba[4*j + 1] )
 					&& ( rgba[4*i + 2] == rgba[4*j + 2] )
-				&& ( rgba[4*j + 3] != 0 || !isDxt1 );
+					&& ( rgba[4*j + 3] != 0 || !isDxt1 ); // @@ I think this check is not necessary.
+
 				if( match )
 				{
 					// get the index of the match
@@ -112,7 +97,25 @@ ColourSet::ColourSet( u8 const* rgba, int flags )
 					break;
 				}
 			}
-#endif
+		}
+		else
+		{
+			// normalise coordinates to [0,1]
+			float x = ( float )rgba[4*i + 2] / 255.0f;
+			float y = ( float )rgba[4*i + 1] / 255.0f;
+			float z = ( float )rgba[4*i + 0] / 255.0f;
+			
+			// ensure there is always non-zero weight even for zero alpha
+			float w = ( float )( rgba[4*i + 3] + 1 ) / 256.0f;
+
+			// add the point
+			m_points[m_count] = Vec3( x, y, z );
+			m_weights[m_count] = ( weightByAlpha ? w : 1.0f );
+			m_remap[i] = m_count;
+			
+			// advance
+			++m_count;
+		}
 	}
 	
 #if SQUISH_USE_SIMD

src/nvtt/squish/colourset.h

@@ -37,7 +37,7 @@ namespace squish {
 class ColourSet
 {
 public:
-	ColourSet( u8 const* rgba, int flags );
+	ColourSet( u8 const* rgba, int flags, bool createMinimalSet = false );
 
 	int GetCount() const { return m_count; }
 	Vec3 const* GetPoints() const { return m_points; }