Stuck on "Unable to end render pass"

[dreammakeplay]

Hello,

I'm stuck on this error message while trying to render a simple triangle (much like the example code) with latest wgpu-native source.

I had my test code running on a previous (months old) version of wgpu-native, but recently synced to latest. I had to update all my code to use the newly refactored wgpu-native APIs and also switched my shaders from using spriv to wgls shaders. After the conversion, I now crash on first render frame when I call 'wgpuRenderPassEncoderEnd' with the specified error message, but I have no idea why.

I'm not getting any other errors. Any idea what might be causing this? Or how to get a more detailed error info?
I can provide more info as needed.

Thanks in advance!

• Chris

P.S. I'm compiling on Windows using VS2022. the wgpu-native libs are compiled locally with latest source (as of this post). The example wgpu-native projects wont compile successfuly, unfortunately, so I can't run and test them locally.

[rajveermalviya]

Hello 👋,

You seem to be hitting a panic here, though it definitely needs better message.

Anyways, you should be able to get some errors via wgpuDeviceSetUncapturedErrorCallback, you can refer to triangle example. Can you check if that reports something for you?

[dreammakeplay]

Thank you for the assist!

I just added the callbacks for wgpuDeviceSetUncapturedErrorCallback, wgpuDeviceSetDeviceLostCallback, and 'wgpuSetLogLevel(WGPULogLevel_Trace)'. Nothing jumped out, except for one thing:

I got a "trace" with "tex 0: insert start UNINITIALIZED"...

I'll dig at that and also do another pass to see what's different between my code and the "triangle example"

Thank you again,

WGPU [Debug] : Resolving [1] = FunctionArgument(0) : Handle([1])
WGPU [Debug] : Resolving [2] = As { expr: [1], kind: Sint, convert: Some(4) } : Value(Scalar { kind: Sint, width: 4 })
WGPU [Debug] : Resolving [3] = Constant([1]) : Value(Scalar { kind: Sint, width: 4 })
WGPU [Debug] : Resolving [4] = Binary { op: Subtract, left: [2], right: [3] } : Value(Scalar { kind: Sint, width: 4 })
WGPU [Debug] : Resolving [5] = As { expr: [4], kind: Float, convert: Some(4) } : Value(Scalar { kind: Float, width: 4 })
WGPU [Debug] : Resolving [6] = Constant([2]) : Value(Scalar { kind: Uint, width: 4 })
WGPU [Debug] : Resolving [7] = Binary { op: And, left: [1], right: [6] } : Handle([1])
WGPU [Debug] : Resolving [8] = As { expr: [7], kind: Sint, convert: Some(4) } : Value(Scalar { kind: Sint, width: 4 })
WGPU [Debug] : Resolving [9] = Constant([3]) : Value(Scalar { kind: Sint, width: 4 })
WGPU [Debug] : Resolving [10] = Binary { op: Multiply, left: [8], right: [9] } : Value(Scalar { kind: Sint, width: 4 })
WGPU [Debug] : Resolving [11] = Constant([1]) : Value(Scalar { kind: Sint, width: 4 })
WGPU [Debug] : Resolving [12] = Binary { op: Subtract, left: [10], right: [11] } : Value(Scalar { kind: Sint, width: 4 })
WGPU [Debug] : Resolving [13] = As { expr: [12], kind: Float, convert: Some(4) } : Value(Scalar { kind: Float, width: 4 })
WGPU [Debug] : Resolving [14] = Constant([4]) : Value(Scalar { kind: Float, width: 4 })
WGPU [Debug] : Resolving [15] = Constant([5]) : Value(Scalar { kind: Float, width: 4 })
WGPU [Debug] : Resolving [16] = Compose { ty: [2], components: [[5], [13], [14], [15]] } : Handle([2])
WGPU [Debug] : Resolving [1] = Constant([5]) : Value(Scalar { kind: Float, width: 4 })
WGPU [Debug] : Resolving [2] = Constant([4]) : Value(Scalar { kind: Float, width: 4 })
WGPU [Debug] : Resolving [3] = Constant([4]) : Value(Scalar { kind: Float, width: 4 })
WGPU [Debug] : Resolving [4] = Constant([5]) : Value(Scalar { kind: Float, width: 4 })
WGPU [Debug] : Resolving [5] = Compose { ty: [2], components: [[1], [2], [3], [4]] } : Handle([2])
WGPU [Info] : Created render pipeline Valid((0, 1, Vulkan)) with RenderPipelineDescriptor { label: Some("Geom RenderPipeline"), layout: Some((0, 1, Vulkan)), vertex: VertexState { stage: ProgrammableStageDescriptor { module: (0, 1, Vulkan), entry_point: "vs_main" }, buffers: [] }, primitive: PrimitiveState { topology: TriangleList, strip_index_format: None, front_face: Ccw, cull_mode: Some(Back), unclipped_depth: false, polygon_mode: Fill, conservative: false }, depth_stencil: None, multisample: MultisampleState { count: 1, mask: 4294967295, alpha_to_coverage_enabled: false }, fragment: Some(FragmentState { stage: ProgrammableStageDescriptor { module: (0, 1, Vulkan), entry_point: "fs_main" }, targets: [Some(ColorTargetState { format: Bgra8UnormSrgb, blend: Some(BlendState { color: BlendComponent { src_factor: One, dst_factor: Zero, operation: Add }, alpha: BlendComponent { src_factor: One, dst_factor: Zero, operation: Add } }), write_mask: RED | GREEN | BLUE | ALPHA | COLOR | ALL })] }), multiview: None }
WGPU [Info] : configuring surface with SurfaceConfiguration { usage: RENDER_ATTACHMENT, format: Bgra8Unorm, width: 800, height: 600, present_mode: Fifo, alpha_mode: Auto }
WGPU [Info] : Automatically choosing alpha mode by rule Auto. Chose Opaque
'test_d.exe' (Win32): Loaded 'C:\Windows\System32\AppXDeploymentClient.dll'.
'test_d.exe' (Win32): Loaded 'C:\Windows\System32\DriverStore\FileRepository\64zh1339.inf_amd64_049a1eb556a79dfd\ig9icd64.dll'.
'test_d.exe' (Win32): Loaded 'C:\Windows\System32\powrprof.dll'.
'test_d.exe' (Win32): Loaded 'C:\Windows\System32\umpdc.dll'.
WGPU [Trace] : 	tex 0: insert start UNINITIALIZED
WGPU [Debug] : Create view for texture (0, 1, Vulkan) filters usages to COLOR_TARGET
WGPU [Trace] : Encoding render pass begin in command buffer (0, 1, Vulkan)
Exception thrown at 0x00007FFB95B1FAEC in test_d.exe: Microsoft C++ exception:  ?? ::st_panic at memory location 0x0000007C0B9FEA38.
Unhandled exception at 0x00007FFB95B1FAEC in test_d.exe: Microsoft C++ exception:  ?? ::st_panic at memory location 0x0000007C0B9FEA38.

[dreammakeplay]

I found my bug,

When calling 'wgpuDeviceCreateSwapChain()`, I had hard-coded the 'format' to 'WGPUTextureFormat_BGRA8Unorm' instead of setting it to 'wgpuSurfaceGetPreferredFormat()' :\

Thank you for all the help!

• Chris