POLYTYPE_ATEX (3) - Linux Man Pages
POLYTYPE_ATEX: Polygon rendering mode type Allegro game programming library.
POLYTYPE_ATEX - Polygon rendering mode type Allegro game programming library.
An affine texture mapped polygon. This stretches the texture across the
polygon with a simple 2d linear interpolation, which is fast but not
mathematically correct. It can look OK if the polygon is fairly small or
flat-on to the camera, but because it doesn't deal with perspective
foreshortening, it can produce strange warping artifacts. To see what this
means, run Allegro's test program and see what happens to the polygon3d()
test when you zoom in very close to the cube.