I'd prefer not to change it. Mathematically, 0 degrees is right. Consider that movement at 0 degrees is X + D cos(0) on the X axis and Y + D sin (0) on the Y axis. cos(0) is 1 and sin(0) is 0, meaning movement right on the X axis at an angle of 0 degrees. It is very much beneficial to keep it plainly mathematical like this: if you hack it so 0 degrees is up, the formula begin to look like cos(angle - 90), with a modification to the angle. This means you can no longer express in your events custom movement as being X + D cos(angle): you will have to also apply the hack to make it compatible with Construct's built in angles, and any modification would not be obvious to a game developer. Even worse if people can invent their own angle systems: in any given game, you simply would have no idea what an angle actually means (would 0 degrees mean up? left? down? south-south-west?). I certainly want to avoid situations where people have to invert, offset and normalise angles just to make them compatible with some other angle system, I've had to do that before for games and it's nontrivial.