Method convertScreenToMap

src/Battlescape/Camera.cpp:458–474

* Converts screen coordinates to map coordinates. * @param screenX Screen x position. * @param screenY Screen y position. * @param mapX Map x position. * @param mapY Map y position. */

 * @param mapY Map y position.
 */
void Camera::convertScreenToMap(int screenX, int screenY, int *mapX, int *mapY) const
{
	// add half a tileheight to the mouseposition per layer we are above the floor
	screenY += (-_spriteWidth/2) + (_mapOffset.z) * ((_spriteHeight + _spriteWidth / 4) / 2);

	// calculate the actual x/y pixelposition on a diamond shaped map
	// taking the view offset into account
	*mapY = - screenX + _mapOffset.x + 2 * screenY - 2 * _mapOffset.y;
	*mapX = screenY - _mapOffset.y - *mapY / 4 - (_spriteWidth/4);

	// to get the row&col itself, divide by the size of a tile
	*mapX /= (_spriteWidth / 4);
	*mapY /= _spriteWidth;

	minMaxInt(mapX, -1, _mapsize_x);
	minMaxInt(mapY, -1, _mapsize_y);
}

/**
 * Converts map coordinates X,Y,Z to screen positions X, Y.