fix opacity vs. transparency issues with UsdPreviewSurface and pxrUsdPreviewSurface#626

Merged

kxl-adsk merged 3 commits intoAutodesk:devfrom mattyjams:pr/UsdPreviewSurface_fragment_graph_opacity_vs_transparency

Jul 7, 2020

+206-93

Commits on Jul 6, 2020

add a UsdPreviewSurfaceCore fragment graph that accepts transparency instead of opacity
mattyjams
committed
rewire UsdPreviewSurface to take advantage of the new UsdPreviewSurfaceCore
mattyjams
committed
use UsdPreviewSurfaceCore in the shading node override for pxrUsdPreviewSurface
mattyjams
committed