I also have a similar engine, it's called PixelPerfectEngine (repository found here
, and it's still under development, and I still haven't tested it on Raspberry Pi as some of the drawing functions still don't have non-SSE2 implementations. It's written in D, but with the LDC compiler it should work with Raspberry Pi (well, after I write non-x86 implementations of the drawing functions).
Currently implemented features:
-Tile and sprite layers.
-8 bit bitmaps for accessing a 256 color palette set somewhere in the memory (including the 65536 color master palette), 16 bit bitmaps for accessing any color of the master palette, 32 bit bitmaps for non-indexed bitmaps.
-Transparency support via alpha blending. Blitter is also available if transparencies are not needed (no real performance benefits on my AMD Athlon 64 x2 config).
-Built in AmigaOS/RiscOS influenced framework for various applications (eg: in-engine editor)
Planned in the future:
-Custom sound engine with sample-based synthesizer.
-Sprite scaling and rotation.
-GPU acceleration through either OpenCL, Cuda, or GPU assembly (which is required for the Broadcom Videocore IV).