cd44449578
This way memory overhead caused by the BVH building is not so visible and peak memory usage will be reduced. Implementing this idea is not so straightforward actually, because we need to synchronize images used for true displacement before meshes. Detecting whether image is used for true displacement is not so striaghtforward, so for now all all displacement types will synchronize images used for them. Such change brings memory usage from 4.1G to 4.0G with the 01_01_01_D scene from gooseberry. With 01_01_01_G scene it's 7.6G vs. 6.8G (before and after the patch). Reviewers: campbellbarton, juicyfruit, brecht Subscribers: eyecandy Differential Revision: https://developer.blender.org/D1217