WIP, NOT WORKABLE YET!

small3dlib

3D software rasterizer for (not only) resource-limited computers.

If you like this, you may also like my similar project: raycastlib.

eye-candy previews

TODO

features

• Very fast, small and efficient.
• Uses only integer math (32bit).
• No dependencies (uses only stdint standard library), extremely portable.
• Single header, KISS.
• Pure C99, tested to run as C++ as well.
• Still flexible -- pixels are left for you to draw in any way you want with a custom fragment-shader like function.
• Perspective correction, 3 modes: none (linear only), full (per-pixel), approximation (per-N-pixels).
• Different drawing strategies to choose from: none, z-buffer (none, full, reduced), triangle sorting (back-to-front, fron-to-back with stencil buffer).
• Triangles provide barycentric coordinates, thanks to which practically anything that can be achieved with OpenGL can be achieved (texturing, shading, normal-mapping, transparency, PBR, shadow mapping, ...).
• Tested on multiple platforms (PC, Arduboy, Pokitto, Gamebuino META).
• Many compile-time options to tune the performance vs quality.
• Well commented and formatted code.
• Completely free of legal restrictions, do literally everything you want.

limitations

• Some values, like screen resolution, are a compile-time option due to performance and simplicity, and can't change during runtime.
• No scenegraph (object parenting), just a scene list. Parenting can still be achieved by using cutom transform matrices.
• Though performance is high, due to multiplatformness it can't match platform-specific rasterizers written in assembly.
• Proper near-plane culling (subdividing triangles) is missing. You can either cull whole triangles completely or "push" them by the near plane. These options are okay when drawing a models not very close to the camera, but e.g. 3D environments may suffer from artifacts.
• Due to the limitations of 32bit integer arithmetics, some types of movement (particularly camera) may look jerky, and artifact may appear in specific situations.

how to use

TODO

tips/troubleshooting

• Seeing buggy triangles flashing in front of the camera? With the limited 32bit arithmetic far-away things may be overflowing. Try to scale down the scene. If you also don't mind it, set S3L_STRICT_NEAR_CULLING to 1 -- this should probably solve it.
• Sorted mode sorts triangles before drawing, but sometimes you need to control the drawing order more precisely. This can be done by reordering the objects in the scene list or rendering the scene multiple times without clearing the screen.