=== Coordinates ===
* sx,sy,dx and dy use image space coordinates. This is Image space width can be 256, 512, 1024 or 2048 pixels width. Image space coordinates are not the same as the display coordinates and display width and height. Coordinate masking is based on image space coordinates.
* the image space height is computed from the vram size, bits per pixel and image space width based on an equation like this: