so they will not be zero when viewing the board com the top/bot.
This was causing problems with BBox intersect function that was using
invDir values.
Fixes lp:1828747
https://bugs.launchpad.net/kicad/+bug/1828747
Additionally, fix an unreported bug allowing zoom level to get stuck at
MAX_ZOOM.
Fixes: lp:1625754 (3dviewer zoom not limited with Use touchpad to pan)
https://bugs.launchpad.net/kicad/+bug/1625754
+re-implement anti-aliasing, making it more acurate, not blured, better
and much faster (unsing much less lines of code)
+rewrite some function on camera and raypacket.
+small improvements on raytracing realtime, remove useless ifs
comparisons.
* Split and rewrite the preview window and canvas.
* Create a new class for handling the board information.
* Adds new render targets: openGL, legacy, and ray tracing.
* Render targets take full advantage of the new 3D plugins system and 3D cache
for a fast 3D model loading.
* Faster board loading.
* New OpenGL render is faster than the old one.
* New ray tracing render target with a post processing shader.
* Use of new 3D plugins (WRL, X3D, STEP and IGES) and 3D model caching.
* Preview of 3D model while browsing the file name.
* 3D preview of the footprint while adding / align 3D shapes.
* Render of 3D models according to attributes: Normal, Normal+Insert, Virtual.
* Pivot rotation centered in one point over the PCB board.
* Shortcuts keys improved for XYZ orientation..
* Animated camera.
Mario Luzeiro
Simon Wells
José Ignacio Romero
Jon Neal
Cirilo Bernardo
Mario Luzeiro