Fix motion blur on skinned meshes #18712
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…s`. This fixes specialization caching the wrong flag.
IceSentry
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## Objective Fix motion blur not working on skinned meshes. ## Solution `set_mesh_motion_vector_flags` can set `RenderMeshInstanceFlags::HAS_PREVIOUS_SKIN` after specialization has already cached the material. This can lead to `MeshPipelineKey::HAS_PREVIOUS_SKIN` never getting set, disabling motion blur. The fix is to make sure `set_mesh_motion_vector_flags` happens before specialization. Note that the bug is fixed in a different way by #18074, which includes other fixes but is a much larger change. ## Testing Open the `animated_mesh` example and add these components to the `Camera3d` entity: ```rust MotionBlur { shutter_angle: 5.0, samples: 2, #[cfg(all(feature = "webgl2", target_arch = "wasm32", not(feature = "webgpu")))] _webgl2_padding: Default::default(), }, #[cfg(all(feature = "webgl2", target_arch = "wasm32", not(feature = "webgpu")))] Msaa::Off, ``` Tested on `animated_mesh`, `many_foxes`, `custom_skinned_mesh`, Win10/Nvidia with Vulkan, WebGL/Chrome, WebGPU/Chrome. Note that testing `many_foxes` WebGL requires #18715.
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As a side note, I really dislike the |
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I have a branch that removes I've been sitting on it because I was hoping #18074 would land first and I wouldn't have to fix merge conflicts. But that PR looks like it's still got a long road to walk, so I'll make a PR now for |
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## Objective Add a test that would have caught #16929 and #18712. ## Solution The PR adds a `test_invalid_skinned_mesh` example that creates various valid and invalid skinned meshes. This is designed to catch panics via CI, and can be inspected visually. It also tests skinned meshes + motion blur.  The screenshot shows all the tests, but two are currently disabled as they cause panics. #18074 will re-enable them. ### Concerns - The test is not currently suitable for screenshot comparison. - I didn't add the test to CI. I'm a bit unsure if this should be part of the PR or a follow up discussion. - Visual inspection requires understanding why some meshes are deliberately broken and what that looks like. - I wasn't sure about naming conventions. I put `test` in the name so it's not confused with a real example. ## Testing ``` cargo run --example test_invalid_skinned_mesh ``` Tested on Win10/Nvidia, across Vulkan, WebGL/Chrome, WebGPU/Chrome.
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Objective
Fix motion blur not working on skinned meshes.
Solution
set_mesh_motion_vector_flagscan setRenderMeshInstanceFlags::HAS_PREVIOUS_SKINafter specialization has already cached the material. This can lead toMeshPipelineKey::HAS_PREVIOUS_SKINnever getting set, disabling motion blur.The fix is to make sure
set_mesh_motion_vector_flagshappens before specialization.Note that the bug is fixed in a different way by #18074, which includes other fixes but is a much larger change.
Testing
Open the
animated_meshexample and add these components to theCamera3dentity:Tested on
animated_mesh,many_foxes,custom_skinned_mesh, Win10/Nvidia with Vulkan, WebGL/Chrome, WebGPU/Chrome. Note that testingmany_foxesWebGL requires #18715.