How to make Interactive Texture?

Thanks DJMidKnight for the answer. I will check that out.But i dont need a button in room. I have attached a image. you can see from that i have created two HUD buttons (Floor,Wall). When i click on that I want the texture to change respective of what I’m clicking. You can see from the image i have posted before that I am doing this action by pressing G. I want the same effect to come on these HUD Buttons. Thanks in advance.

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