如何使用Pixmap Libgdx进行碰撞

I am making a game where a block that is black is falling down in a white background. My avatar, which is red is dodging the black blocks but if it hits the black block, the game is over. Can someone give me a hand in starting this? I just want the avatar to check if the pixel at the location of the block is black or white. Thanks.I am making a game where a block that is black