Android diagonal triangle buttons

Question

I am working on an android application.

I need to have 2 buttons but similar to the following picture.

The red triangle is a button and the yellow is another button.

How can this be achieved?

Is there a way to do it other than having it as 1 picture and then checking the touch position? because that would involve a lot of math and might not be precise. Also if I use this method I cannot have a clicked state on the each button seperatly. (like when the button grays out on touch down)

Thanks for any tips.