private Vector3 RenderPixel(Scene scene, int screenX, int screenY, float dX, float dY, int pictureHeight,
int pictureWidth)
{
var viewportX = (screenX + dX)/pictureWidth*2 - 1;
// Screen Y is pointed down
var viewportY = 1 - (screenY + dY)/pictureHeight*2;
return scene.SampleColor(viewportX, viewportY, 4);
}
