Through a process of elimination, I found the problem was assigning a variable from another that contains a sprite.
This fragment demonstrates the problem.
Code: Select all
a = sprite_build([[1, 0, 0, 0, 1], [0, 1, 0, 1, 0], [0, 0, 1, 0, 0], [0, 1, 0, 1, 0], [1, 0, 0, 0, 1]]);
b = a;