Allow imgui to render into a multisampled Vulkan framebuffer #2706
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ImGui always sets the MSAA level to 1 sample, disabling it. This means you get errors if you try to render with ImGui's into a multisampled framebuffer in Vulkan, because Vulkan requires you to specify the correct multisampling level at pipeline creation time. This change adds a new member to the `ImGui_ImplVulkan_InitInfo` struct which users of ImGui can set to the correct multisample level for their target frame buffer. The zero value (which you'll get by default if the struct has been zero-initialised) is not a valid MSAA level in Vulkan, so we detect that case and use `VK_SAMPLE_COUNT_1_BIT` instead at setup time. Unless you've explicitly set the MSAASamples to something, the default behaviour should be exactly as it was previously, i.e. multisampling will be disabled.
examples/imgui_impl_vulkan.cpp
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| } | ||
| else { | ||
| ms_info.rasterizationSamples = VK_SAMPLE_COUNT_1_BIT; | ||
| } |
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Thanks!
Might want to remove those braces, update local changelog at the top of imgui_impl_vulkan.cpp and docs/Changelog.
I'll do those changes if you need.
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Oops, I'll remove those braces. I didn't notice that it wasn't in line with ImGui style. Sorry!
Would text like this be ok for the changelog in imgui_impl_vulkan.cpp?
// 2019-07-31: Vulkan: Added support for specifying multisample count. Set ImGui_ImplVulkan_InitInfo::MSAASamples to one of the VkSampleCountFlagBits values to use, default is non-multisampled as before.
And would it be the same text, in the version 1.73 section, for docs/Changelog?
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(I'm actually doing a bit of a rollback and releasing a hotfix 1.72b to fix a navigation issue now, so your patch may be in it or not.)
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OK great, I've added those changes to the PR. Thanks!
- Add changelog comments to both imgui_impl_vulkan.cpp and docs/CHANGELOG.txt describing the multisample change. - Remove unnecessary braces around single line if & else statements, to match ImGui coding style.
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Merged, thank you! |
ImGui always sets the MSAA level to 1 sample, disabling it. This means you get errors if you try to render with ImGui's into a multisampled framebuffer in Vulkan, because Vulkan requires you to specify the correct multisampling level at pipeline creation time.
This change adds a new member to the
ImGui_ImplVulkan_InitInfostruct which users of ImGui can set to the correct multisample level for their target frame buffer. The zero value (which you'll get by default if the struct has been zero-initialised) is not a valid MSAA level in Vulkan, so we detect that case and useVK_SAMPLE_COUNT_1_BITinstead at setup time. Unless you've explicitly set the MSAASamples to something, the default behaviour should be exactly as it was previously, i.e. multisampling will be disabled.This fixes issue #2705
Feedback very much appreciated!