Update README.md

README.md

@@ -4,4 +4,38 @@
 
 3D software rasterizer for (not only) resource-limited computers.
 
-If you like this, you may also like my similar project: [raycastlib](https://gitlab.com/drummyfish/raycastlib).
+If you like this, you may also like my similar project: [raycastlib](https://gitlab.com/drummyfish/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. 
+- 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
+
+- 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 int arithmetic, some types of movement may be jerky.
+
+TODO
+
+## how to use
+
+TODO
+
+## tips
+
+- 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.