<html> <head> <base href="https://bugs.freedesktop.org/"> </head> <body> <div> <a class="bz_bug_link bz_status_REOPENED " title="REOPENED - Using a single-plane imageview from a multi-plane image is broken" href="https://bugs.freedesktop.org/show_bug.cgi?id=105496#c17">Comment # 17</a> on <a class="bz_bug_link bz_status_REOPENED " title="REOPENED - Using a single-plane imageview from a multi-plane image is broken" href="https://bugs.freedesktop.org/show_bug.cgi?id=105496">bug 105496</a> from <a class="email" href="mailto:atomnuker@gmail.com" title="atomnuker@gmail.com">atomnuker@gmail.com</a> <pre>(In reply to Lionel Landwerlin from <a href="show_bug.cgi?id=105496#c16">comment #16</a>) > (In reply to atomnuker from <a href="show_bug.cgi?id=105496#c15">comment #15</a>) > > (In reply to Lionel Landwerlin from <a href="show_bug.cgi?id=105496#c14">comment #14</a>) > > > The ffmpeg repo I built locally had the image below bound to a G8_B8_R8 > > > image. > > Yes, the one before I pushed. I only used 1 plane in order to test easily > > without modifying lots of code. > > > > > layout (set = 0, binding = 0, rgba8) uniform readonly image2D input_img; > > > > > > But somehow it should contain all the planes? > > Like I said, no, just one: the one with the aspect (plane) you chose via the > > VkImageView. > > > > To illustrate: > > VkImage (VK_FORMAT_G8_B8R8_2PLANE_420_UNORM_KHR) -> create VkImageView > > (VK_FORMAT_R8_UNORM and aspect VK_IMAGE_ASPECT_PLANE_0_BIT_KHR) -> bind to > > descriptor which describes a storage image inside the shader -> > > imageLoad(input_img, vec2(0)).r will output the pixel of the image at > > location x=0, y=0. > > We can't do that, because enabling storage support on a > VK_FORMAT_G8_B8R8_2PLANE_420_UNORM_KHR image means we would need to support > that storage on that entire format too (not just on one plane). We must: the spec explicitly states that API users MUST check if the VkFormat supports the STORAGE bit for the current tiling mode. If its not flagged, then the STORAGE usage bit MUST NOT be present when creating the image. If the storage bit isn't enabled then any VkImageViews created from the VkImage will not support storage, even if the VkFormat of the VkImageView supports the STORAGE bit for the particular tiling mode. Hence, we must flag the STORAGE bit for the VkFormat, even if users can't directly access all the planes via a single image2D. I can propose that the spec is changed such that it mentions this, if it makes you feel more comfortable. But to move forward and enable users to do _actual_ useful things to multiplane images (and not take chances by flagging usages reported to be unsupported) we should flag this.</pre> </div> <hr> You are receiving this mail because: <ul> <li>You are the QA Contact for the bug.</li> </ul> </body> </html>