View source for Rendering engine

Stunts' rendering engine has (at least) two layers.

Layer 1 determines which tiles should be drawn, and which shapes in each tile. This task is performed by the function called [https://github.com/4d-stunts/restunts/blob/master/src/restunts/c/frame.c update_frame].

Layer 2 takes each shape and determines its primitives. This task is performed by the function called [https://github.com/4d-stunts/restunts/blob/master/src/restunts/c/shape3d.c transformed_shape_op] (at least as of commit aec11f4; a better name could be helpful).

Both layer 1 and layer 2 were ported to C language as part of the [[Restunts]] project. However, while level 1's code is readable and straightforward ([[HerrNove]] left comments in most of the functions and can support if further help is needed), level 2 remains mostly a mystery. Most of the instructions are just uncommented disassembly from IDA, and some parts are simply not implemented.

=== Layer 1 ===

TODO. For now, have a look at [https://marnetto.net/2025/02/20/broderbund-stunts-1 this writeup],especially the section “A tile-based graphics engine”.

=== Layer 2 ===

TODO

'''Notes'''

* Flagging polygons as 2-sided disables angular culling
* The first shapes in a car file are taken by Stunts to be the front wheels. They are subject to special geometrical transformations when the car steers, to make them turn with respect to the car's body.


[[Category:Internals]]