int scene_polygon3d(int type, BITMAP *texture, int vc, V3D *vtx[]);
int scene_polygon3d_f(int type, BITMAP *texture, int vc, V3D_f *vtx[]);
Arguments are the same as for polygon3d(), except the bitmap is missing. The one passed to clear_scene() will be used.
Unlike polygon3d(), the polygon may be concave or self-intersecting. Shapes that penetrate one another may look OK, but they are not really handled by this code.
Note that the texture is stored as a pointer only, and you should keep the actual bitmap around until render_scene(), where it is used.
Since the FLAT style is implemented with the low-level hline() function, the FLAT style is subject to DRAW_MODEs. All these modes are valid. Along with the polygon, this mode will be stored for the rendering moment, and also all the other related variables (color_map pointer, pattern pointer, anchor, blender values).
The settings of the CPU_MMX and CPU_3DNOW flags of the cpu_capabilities global variable on entry in this routine affect the choice of low-level asm routine that will be used by render_scene() for this polygon.