Hi @dhart, I find that setting the variable transform of IAS build input using the object-to-world matrix is correct.
Here is my simple test:
- First, I make the camera look at the center of the scene's AABB. I construct the AABB according to the local mesh transformed by object-to-world matrix.
- Then, while running my program, I can see my scene only if I set the variable transform as the object-to-world matrix instead of the world-to-object one.
And I find what sutil/Scene.cpp does is also to set that variable as an object-to-world matrix.
So, the annotation of the header file seems wrong.
By the way, I find another mistake of the header file sutil/Aabb.h (line 31):
- Should #include instead of a repeat #include