Depth buffer is broken

[AlexMollard]

Depth Buffer Discarding All Pixels

Problem Description

The depth buffer is currently malfunctioning, discarding every pixel in each frame. This results in incorrect depth testing and rendering artifacts, severely impacting the visual quality and accuracy of the 3D scene.

Symptoms

• Objects appear to render in incorrect order (z-fighting)
• All objects visible regardless of their position in the scene
• Lack of proper occlusion between objects
• When enabled nothing renders (All fail the depth test)

Potential Causes

1. Incorrect depth attachment setup in the render pass
2. Improper depth test configuration in the pipeline state
3. Shader issues related to depth writing or testing
4. Misconfigured viewport or scissor settings
5. Incorrect clear values for the depth buffer
6. Unintended depth buffer clears between draw calls

Investigation Steps

1. Verify depth attachment creation and format
2. Check the depth test and write settings in the pipeline state
3. Review shader code for depth-related operations
4. Examine viewport and scissor configurations
5. Inspect clear values and operations for the depth buffer
6. Analyze the rendering loop for unintended state changes

Possible Solutions

• Correct depth attachment setup in render pass creation
• Adjust pipeline state to enable proper depth testing and writing
• Modify shaders if they're improperly handling depth
• Ensure correct viewport and scissor settings
• Verify and correct depth buffer clear operations

Impact

Resolving this issue is critical for:

• Correct rendering of 3D scenes
• Proper occlusion and object ordering
• Enabling advanced rendering techniques that rely on accurate depth information (e.g., shadow mapping, depth-based effects)

Testing

After implementing fixes:

• Render test scenes with overlapping objects at various depths
• Verify correct occlusion and depth ordering
• Perform visual inspections and automated tests to ensure depth buffer integrity
• Add another pipeline that could combine multiple pipeline results into one (Composite step)

[AlexMollard]

Issue Resolved

Cause

The colorBlendAttachment.colorWriteMask was not properly set in the graphics pipeline configuration.

Solution

I updated the pipeline creation to correctly set the color write mask.

Commit

The fix has been implemented in the following commit: 71e5cf6: Fixed depth buffer, Adjusted the debug utils as the colours made it hard to debug in renderdoc.