I’ve been “greyboxing” a large level for a commercial project (essentially blocking out without textures to test the layout, just lighting with dynamic vertex lighting… alongside that I’ve been experimenting with GLSL, lightmapping and materials in general, ready for the next pass.
I have a milestone at the end of this week, so started to lightmap the whole thing today…
BANG, now I have textures flickering on and off the geometry, applied to faces that have no material or UV editor assigned texture, and textured materials that start corrupt, but when I turn the camera they start rendering correctly…looks like memory trampling that I used to see at my old companies ps2 engine…
I’m also getting random triangle sorting very badly ( or just not being drawn). luckily I can do the milestone without lightmaps, it just won’t be quite as good as I hoped. This doesn’t look good for the next milestone however as I need a large part of the world multi textured for that.
sadly because of NonDisclosureAgreement I can’t post the file here, I can just describe the problem!
I had hoped that I could do the whole thing inside the blender GE, but if I can’t resolve this issue that would be impossible!
I’m mixing textured and untextured objects on different layers , some with a large bounding boxs, all overlapping…
the world is approx 650 units @1m per unit… the main area is 100 units in the middle. vertex count is around 80 000 face count 78400 (mostly quads) Mem 45M (81m)
I’m running Linux (ubuntu gutsy) with an nvidia Geforce go 7950GTX running the non free drivers (it should be able to eat this scene for breakfast, and indeed I’ve run much more complex counts from within blender…
Try booting into windows and see how the proper drivers operate…
If you have the same problems, you might want to look into buying a new graphics adapter.
What you are describing is what it looks like when there is a GPU failure.
It’s the same in windows… only the frame rate’s a lot less!
I’m pretty sure it’s a software thing though, (better be, a fried graphics card is all I need!)
it looks a lot like when a games team is transitioning the renderer and the assets have’t been updated to the new system…
Makes me think it must be in the combination of sizes, object centers, clipping, culling, and the various render systems (un-textured, textured, gLSL…)
haven’t tried using tris yet either…
These shots don’t give anything away, but illustrate the problem…
shot 1, left sphere is corrupt, turn, get shot 2 with sphere drawn right
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the garbage to the right of the figure looks like flipped normals, but is just bad sorting… the uvz are probably highly discontinuous here…
Turns out it was stupidity on my part… apart from 1 mystery…
I hadn’t assigned materials to some of the meshes, but had assigned lightmaps in UVeditor… these are the objects that were displaying correctly then flicking to corrupted madness…
adding a material with “texface” and a channel set to use UV fixed the flicking…
Strangely this wasn’t a problem on my old computer with an older graphics card!
The sorting problem, it seems I had turned on “use alpha” in the texture buttons by mistake, (probably trying to bug fix the sorting… Strangely this in itself din’t fix the problem, but turning it off and turning on ztransp fixed it!
I thought ztransp was only for when you had transparent stuff, but it’s helped here.
I still get some sorting issues, but they are limited to when i move across the seam between two objects, and then only on the adjacent polygons.
