Freeware cross-platform scanline based 2D graphics engine for the creation of retro/style arcade games. It natively supports raster effects (changing rendering parameters between scanlines) which were an advanced technique of high profile 2D games. It features background transform (rotation & scaling), sprite scaling, transparency effects, built-in animation sequencer for tiles, sprites & palettes. C API and python wrapper.
This example uses two multiplexing layers, raster effect to generate the sky gradient, variable blending for the clouds, and sprite animation for the objects.