Add comparison operator for pixels

PVRTCEncoder/src/Pixel.cpp

@@ -163,5 +163,19 @@ namespace PVRTCC {
     return r;
   }
 
+  bool Pixel::operator==(const Pixel &other) const {
+    uint8 depths[4];
+    other.GetBitDepth(depths);
+
+    bool ok = true;
+    for(int i = 0; i < 4; i++) {
+      ok = ok && m_BitDepth[i] == depths[i];
+
+      uint8 mask = (1 << depths[i]) - 1;
+      const uint8 c = other.Component(i) & mask;
+      ok = ok && (c == (Component(i) & mask));
+    }
+    return ok;
+  }
 
 }  // namespace PVRTCC

PVRTCEncoder/src/Pixel.h

@@ -111,6 +111,9 @@ class Pixel {
   // up in the most-significant byte.
   uint32 PackRGBA() const;
 
+  // Tests for equality by comparing the values and the bit depths.
+  bool operator==(const Pixel &) const;
+
  private:
   union {
     struct {