WINTERMUTE: Avoid doing alpha-blits when image doesn't have alpha.

Also detect images with only binary alpha.

1 files changed, 6 insertions, 0 deletions

diff --git a/engines/wintermute/graphics/transform_struct.h b/engines/wintermute/graphics/transform_struct.h
index a54c4cc5d0..f4f97d1ea9 100644
--- a/engines/wintermute/graphics/transform_struct.h
+++ b/engines/wintermute/graphics/transform_struct.h
@@ -42,6 +42,12 @@ const int32 kDefaultOffsetX = 0;
 const int32 kDefaultOffsetY = 0;
 const int32 kDefaultAngle = 0;
 
+enum AlphaType {
+	ALPHA_OPAQUE = 0,
+	ALPHA_BINARY = 1,
+	ALPHA_FULL = 2
+};
+
 struct TransformStruct {
 private:
 	void init(Point32 zoom, uint32 angle, Point32 hotspot, bool alphaDisable, TSpriteBlendMode blendMode, uint32 alpha, bool mirrorX, bool mirrorY, Point32 offset);