1 files changed, 39 insertions, 0 deletions
diff --git a/Runtime/Graphics/ETC2Decompression.h b/Runtime/Graphics/ETC2Decompression.h
new file mode 100644
index 0000000..5e97047
--- /dev/null
+++ b/Runtime/Graphics/ETC2Decompression.h
@@ -0,0 +1,39 @@
+#ifndef ETC2DECOMPRESSION_H
+#define ETC2DECOMPRESSION_H
+
+#include "UnityPrefix.h"
+
+// ETC-2 decompressor
+//
+// Input is expected to be in standard ETC-2 (+EAC) memory layout. In ETC2 block size is 64b
+// and alpha EAC block adds another 64b.
+//
+// Output must be RGBA with 8 bits for each channel, stored in R, G, B, A order
+// (from offset 0 to 3).
+//
+// Texture sizes that are not exactly divisible by block size are supported. In such
+// case block count is rounded up and extra decoded pixels are just ignored.
+
+//! ETC2 memory layout configuration
+enum
+{
+	kETC2BlockWidth						= 4,
+	kETC2BlockHeight					= 4,
+	kETC2UncompressedPixelSizeA8		= 1,
+	kETC2UncompressedPixelSizeRGB8		= 3,
+	kETC2UncompressedPixelSizeRGBA8		= 4,
+	kETC2UncompressedBlockSizeA8		= kETC2BlockWidth*kETC2BlockHeight*kETC2UncompressedPixelSizeA8,
+	kETC2UncompressedBlockSizeRGB8		= kETC2BlockWidth*kETC2BlockHeight*kETC2UncompressedPixelSizeRGB8,
+	kETC2UncompressedBlockSizeRGBA8		= kETC2BlockWidth*kETC2BlockHeight*kETC2UncompressedPixelSizeRGBA8
+};
+
+//! Decompress ETC2 to RGBA8 buffer
+void DecompressETC2_RGB8 (UInt8* dst, const UInt8* src, int width, int height);
+
+//! Decompress ETC2 with punchthrough alpha to RGBA8 buffer
+void DecompressETC2_RGB8_A1 (UInt8* dst, const UInt8* src, int width, int height);
+
+//! Decompress ETC2+EAC to RGBA8 buffer
+void DecompressETC2_RGBA8 (UInt8* dst, const UInt8* src, int width, int height);
+
+#endif