On Tue, Jan 06, 2015 at 11:15:58PM +0100, John Paul Adrian Glaubitz wrote: > What exactly do you mean with "rendering tricks"? I'm not such an > expert on OpenSCAD yet. Just recently discovered it thanks to > Torsten :).
openscad utilizes libopencsg, which does geometry differences by flipping around the semantics of the z buffer. (eg to render a spherical hole in a cube, it renders the cube first, then inverts the z-buffer semantics from only rendering pixels in front of already painted pixels to only rendering pixels behind already painted pixels, and then paints the backfaces of the sphere). thus, boolan operations on solids are possible without calculating intersection points of faces, and do things fast on the graphics card ... provided there is one. situations without proper graphics cards are now ok-ish-ly dealt with by software rendering for regression tests, but the emulated graphics card of virtualbox still fails (as it did with the wheezy released openscad), so that's the things i'd need testing from real wheezies. basically, if example001 shows the same after pressing f5 and f6, the graphics card tricks at least basically work. there is a regression testing mechanism in the `openscad-testrun` binary, but i wouldn't rely on that yet for it has to deal with off-screen rendering buffer allocations the real openscad doesn't have to deal with. best regards chrysn
signature.asc
Description: Digital signature
