利用者:DingTo/GSoC 2014/Weekly Reports/Week5

Week 5

What I did this week

• Merged master into my branch (took some time, due to several conflicts) and updated QBVH Code in my Branch with the new SSE classes. (0e62c026ab3d, 611d69adb98b)

• Did some research and experiments on improved QBVH / Triangle Intersection again. https://developer.blender.org/D599 I think the "Watertight Ray/Triangle Intersection" paper + the Embree sample implementation of that is a very nice candidate, but probably a bit over my head for now. It involves changes to BVH build, BVH traversal and Triangle Intersection. Nevertheless would it be a great addition.
  • Memory usage would be reduced (no more __tri_woop data, which would save us 4x float4 per triangle).
  • Improved performance due to Quad BVH + multiple triangle intersections with SIMD.
  • Also not sure how feasible that is for GPU. The algorithm itself does not use CPU only features as far as I can see that, but might need additional work.

• Started to look into ways to avoid unneeded samples for black backgrounds. http://www.pasteall.org/52361/diff I quickly hacked it in for the case, where "Use Nodes" is still disabled for the world. In the final implementation, I need to check the world shader tree, and extract the Background node, to see if the color is black or the strength zero. I am not exactly sure yet, how to do that. Help here is welcome.

• Today I spent time on the bugtracker.
  • Fixed: Issue with Checker Texture, GLSL error with Hair shader: (ead83a48f15c, a5a869c579de)
  • Closed several other reports (Issues has been fixed, or not a bug).

Next week

I will continue to work on the Background Sampling optimization or look into the Smooth Normals (as planned last week).

University exams start in 2 weeks (7 July - 17 July), so I would like to focus on that. When I look at my proposal, half of the tasks are finished + WIP code for 2 more items is there. http://wiki.blender.org/index.php/User:DingTo/GSoC_2014/Proposal I also did additional work + fixes, that should be fine for Midterm I hope. :) I can work almost full time on Cycles from the 18th July to GSoC end (18th August), that should give me enough time to finish my Deliverables + some additional fun. But the upcoming 3-4 weeks will most likely be spend on University. Please tell me if that is ok.

Questions

None.