Blender Git Commit Log
Git Commits -> Revision 1f86434
Revision 1f86434 by Sergey Sharybin (cycles_bvh) June 10, 2016, 14:13 (GMT) |
Cycles: Reduce memory usage by de-duplicating triangle storage There are several internal changes for this: First idea is to make __tri_verts to behave similar to __tri_storage, meaning, __tri_verts array now contains all vertices of all triangles instead of just mesh vertices. This saves some lookup when reading triangle coordinates in functions like triangle_smooth_normal(). In order to make it efficient needed to store global triangle offset somewhere. So no __tri_vindex.w contains a global triangle index which can be used to read triangle vertices. Next idea was to use this __tri_verts instead of __tri_storage in intersection code. Unfortunately, this is quite tricky to do without noticeable speed loss. Current formulation of indices required doing two level lookup, which destroys cache and leads to poor performance, causing up to 8% slowdown here. In order to solve this couple of things were made. Firstly, added an array to look up global triangle offset directly from primitive index. This doesn't affect on overall number of textures because we're getting rid of _-tri_storage anyway. Secondly, did some types changes to avoid casts which are not really coming for free. After doing those tricks it seems slowdown is withing 2% here on my desktop, but today it behaves flackey and doesn't give totally consistent results, so need to doublecheck that). On a positive site we've achived: - Few percent of memory save with triangle-only scenes. Actual save in this case is close to size of all vertices. On a more fine-subdivided scenes this benefit might become more obvious. - Huge memory save of hairy scenes. For example, on koro.blend there is about 20% memory save. On bunny.blend it's hard to measure against current master because beefy machine is occupied atm, but let's put it this way: before this change i was unable to render full bunny on my machine (and it is on 12gig machine, but remember beefy machine was reporting 9 gig peak) and now the scene renders just fine and using 3.3gig. |
Commit Details:
Full Hash: 1f86434ff1374e45bdf9e90c2b21867a74d2991b
Parent Commit: 0e393a3
Lines Changed: +114, -144
9 Modified Paths:
/intern/cycles/bvh/bvh.cpp (+17, -46) (Diff)
/intern/cycles/bvh/bvh.h (+2, -3) (Diff)
/intern/cycles/kernel/geom/geom_motion_triangle.h (+16, -16) (Diff)
/intern/cycles/kernel/geom/geom_triangle.h (+28, -33) (Diff)
/intern/cycles/kernel/geom/geom_triangle_intersect.h (+16, -12) (Diff)
/intern/cycles/kernel/kernel_textures.h (+2, -2) (Diff)
/intern/cycles/render/mesh.cpp (+27, -29) (Diff)
/intern/cycles/render/mesh.h (+4, -1) (Diff)
/intern/cycles/render/scene.h (+2, -2) (Diff)
/intern/cycles/bvh/bvh.h (+2, -3) (Diff)
/intern/cycles/kernel/geom/geom_motion_triangle.h (+16, -16) (Diff)
/intern/cycles/kernel/geom/geom_triangle.h (+28, -33) (Diff)
/intern/cycles/kernel/geom/geom_triangle_intersect.h (+16, -12) (Diff)
/intern/cycles/kernel/kernel_textures.h (+2, -2) (Diff)
/intern/cycles/render/mesh.cpp (+27, -29) (Diff)
/intern/cycles/render/mesh.h (+4, -1) (Diff)
/intern/cycles/render/scene.h (+2, -2) (Diff)