Is there a standard way to let users rotate objects?

1. How do I rotate an object in OpenGL?
2. How is rotating an object different from flipping?
3. How do you rotate doors in Dungeondraft?

How do I rotate an object in OpenGL?

To rotate around a different point, the formula: X = cx + (x-cx)*cosA - (y-cy)*sinA, Y = cy + (x-cx)*sinA + (y-cy)*cosA, cx, cy is centre coordinates, A is the angle of rotation. The OpenGL function is glRotatef (A, x, y, z).

How is rotating an object different from flipping?

When you rotate an object, it moves left or right around an axis and keeps the same face toward you. When you flip an object, the object turns over, either vertically or horizontally, so that the object is now a mirror image.

How do you rotate doors in Dungeondraft?

You can click and drag on it to rotate the object, use the arrows to the side for precise adjustments, or just use your scroll wheel. The scale slider below changes what size the object is. To quickly adjust this, you can hold ALT then scroll to adjust the size as you'd like.