Hi all,
I'd like to consult this omniscient list for a tiny bit of further information. :) The last thing I need to get to work right before I can merge my code into SVN is transformations for 3D boxes (haven't really gotten to touch them so far). Actually, I thought they shouldn't be hard to understand but I find myself fiddling with them and the things that happen are slightly different from what I expect. Would anyone mind giving me some hints as to what happens / should happen in an item's transform method?
As I understand it, the transformation matrix is passed in, but what exactly is coded in this matrix? It looks like an affine transformation, but which point is considered the origin? If I simply multiply some corner, say, with this matrix then the image is off by a certain translation. Is this the translation occurring in the matrix? Where does it come from? Should I simply discard it (as seems to be done for sp_rect)? Or how else can I extract the information I need? Unfortunately I can't simply copy the code from sp-rect.cpp because the boxes are internally stored in a more complicated way than rectangles.
Thanks in advance, Max
P.S.: Upon re-reading this email some ideas of how it could work are forming in my mind but right now I'm too tired to test them. I'm going to get me some hours of sleep and try again, but if anyone has any hints in the meantime I'd still be grateful. ;)