I have a 400x400 image which I need to tile in allegro 5. It will need to tile various sizes so I cannot simply create a larger image. However, a google search returned nothing about this, nor did a search on this site. Is there any way of doing this (like what you can do in DirectX/OpenGL with texture wrapping, clamping and reflecting) without drawing the image over and over again?
Both graphic APIs do that internally, but there is no "tiling" function included on Allegro so you have to implement your own.
Render time impact will be almost non-existing since you will still be below the MILLIONS of triangles per second current cards can draw. As a bonus, you can use al_hold_bitmap_drawing(true) then draw the tiles you wish from the same bitmap to have even more framerate.