how to apply an animation into a triangle(Processing)

Question

I want to create a simple animation, that can only show in a specific area, such as triange. I already have the animation, a rotating picture. but I dont know how to put it into the triangle. the function texture() can only apply images into a specific area. is there other ways to do that? thx!

Answer 1

I can think o several ways to do something like this.

One (Hard) - make the picture a texture on a triangle in 3D, rotate the view by some amount each draw, change the amount each draw.

Two (Medium) - PImage.mask(PImage); where the mask is a picture of a black triangle on a white background

Three (Medium) - use your photoshop skillz to mask the frames of the animation with a trangle before you even export it.

Can we get some more detail here?