Why are the mouse coords that GLFW returns like 20 pixels off in the y axis? Screen resolution on my TV is 1360 x 768. The little red cube above the mouse is hovering almost directly over 0,0,0 in world space, but the mouse cursor is 20 pixels below it on y axis. If I adjust my screen height variable to 748 instead of 768 then the cube and mouse cursor line up perfectly.