LCDBitmap *fadeGradientTransparent = pd->graphics->loadBitmap("images/fade-gradient-transparent", NULL);
int width;
pd->graphics->getBitmapData(fadeGradientTransparent, &width, NULL, NULL, NULL, NULL);
pd->system->logToConsole("%i should be 512", width);
If you build a C project with the above code and include the image below, it will disregard several columns of pixels:
(Note: if you don't see the image above, make sure this web page is displayed with Dark Mode turned off. It's a black image with transparent regions.)
Discovered on a Mac, building with CMake.
The image is 512x20, and the last 20 or so pixels on its end are black and opaque. The C API says it's only 496 pixels wide.