I am reading this lesson from scratchapixel. To my understanding (and the example given in the same website) M is the matrix that transforms from local to world.
Giong through the paragraph before figure 7, though, I get the following:
If we know the 4x4 matrix M that transforms a coordinate system A into a coordinate system B ...
Say A is the local coord system and B is the world coord system. Therefore M transforms from local to world.
... then if we transform a point whose coordinates are originally defined with respect to A with the inverse of M (...), we get the coordinates of P with respect to B.
We know, A = local coord system. The Plocal = local point coords are (-0.5, 0.5, -0.5). Then, as the quoted text says, we transform Plocal with the inverse of M to get the point w.r.t. to B = woorld coord system
However, this last operation (statement) confuses me, since the example they give the do Pworld = Plocal * M. But from the quoted text I understand that Pworld = inv(M) * Plocal
Can someone help me figuring out what am I missing? Is the wording of the text wrong?