[Vulkan Shader Debugging] texelFetch R32_UINT/R16_UINT usampleBuffer always returns 0.

[wumo]

Description

When debugging in vulkan, texelFetch a R32_UINT/R16_UINT usampleBuffer in compute shader will always return 0 while the actual value shown in buffer window isn't 0. If I change the resource from usampleBuffer to storage buffer, then the result seems correct.

Actual buffer value:

Debugging value:

Result:

Steps to reproduce

The compute shader is:

#version 450
layout(local_size_x = 64, local_size_y = 1, local_size_z = 1) in;

layout(set = 0, binding = 0) uniform writeonly image3D ResultTex;
layout(set = 0, binding = 1) uniform usamplerBuffer IdxBuffer;
// layout(set = 0, binding = 1) buffer IdxBuffer {
//     uint Indices[];
// };

void main() {
    // uint Idx = Indices[int(gl_GlobalInvocationID.x)];
    uint Idx = texelFetch(IdxBuffer, int(gl_GlobalInvocationID.x)).x;
    imageStore(ResultTex, ivec3(gl_GlobalInvocationID.xyz), uvec4(Idx) / 64.0);
}

Capture file: capture.zip

Environment

• RenderDoc version: 1.29.0
• Operating System: Windows 10
• Graphics API: Vulkan 1.1.0
• Graphics Card: NVIDIA GeForce RTX 3080
• Graphics Driver: 537.52.0

[wumo]

For now, I'll have to use buffer instead of samplerBuffer to debug.

[baldurk]

That commit should fix the issue, return values from samples in int/uint weren't being properly processed according to their type.