kc3-lang/angle

2020-06-04T23:06:58

Vulkan: Better handling of texture level redefinition If a texture level is being redefined, there are two scenarios to consider: 1. The level is outside the base/max level, for which the image was allocated. 2. The level is within the base/max level, but it's being redefined to a different size or format. In the former case, we simply don't need to release the image. The latter case itself has two possibilities: 2.1. There is only one level in the image. 2.2. There are multiple levels in the image. In case 2.1, the whole image is being redefined (as it has only a single level), so the image can (and should) be released. Prior to this change, this behavior was adopted for all cases. This change retains this behavior for this case only. In case 2.2, the texture is becoming incomplete. However, the image shouldn't yet be released because another one of its mips may be bound to a framebuffer. In such cases as glCopyTexImage2D(), that framebuffer may in fact be the source of the copy operation (which would be destroyed if the image is released). If the base/max level of the texture doesn't change, redefining the level and making the texture incomplete doesn't make the framebuffer incomplete; this is achieved at the same time by not releasing the image. This change ensures that updates to the redefined level are staged in cases 1 and 2.2. Bug: angleproject:4274 Change-Id: I3fac3203c2fbbc16e8e4a35b1334b767120b2dcf Reviewed-on: https://chromium-review.googlesource.com/c/angle/angle/+/2230853 Commit-Queue: Shahbaz Youssefi <syoussefi@chromium.org> Reviewed-by: Jamie Madill <jmadill@chromium.org>