public void DrawUV( Texture srv, Vector3 leftTopCorner, Vector3 rightBottomCorner, Color color, float u, float v, float tw, float th, int clipRectIndex=0 )
{
PushQuad(srv,
new SpriteVertex(leftTopCorner.X, leftTopCorner.Y, leftTopCorner.Z, color, u + 0, v + 0 , clipRectIndex ),
new SpriteVertex(rightBottomCorner.X, leftTopCorner.Y, leftTopCorner.Z, color, u + tw, v + 0 , clipRectIndex ),
new SpriteVertex(rightBottomCorner.X, leftTopCorner.Y, rightBottomCorner.Z, color, u + tw, v + th, clipRectIndex ),
new SpriteVertex(leftTopCorner.X, leftTopCorner.Y, rightBottomCorner.Z, color, u + 0, v + th, clipRectIndex ));
}