nv2a/vk: Relax and simplify surface to texture constraints

[mborgerson]

Improves performance in some cases.

[gemini-code-assist]

Summary of Changes

Hello @mborgerson, I'm Gemini Code Assist¹! I'm currently reviewing this pull request and will post my feedback shortly. In the meantime, here's a summary to help you and other reviewers quickly get up to speed!

This pull request refines the process of converting render surfaces to textures within the nv2a/vk graphics pipeline. It introduces more flexible compatibility checks between surface and texture formats and provides an alternative, potentially more efficient, path for depth/stencil data conversion, aiming to enhance overall rendering performance.

Highlights

• Simplified Surface-to-Texture Compatibility Checks: The logic for determining if a surface can be copied to a texture has been significantly streamlined, replacing a large switch-case with a more generic check based on Vulkan format texel sizes and removing specific format-to-format mappings.
• Conditional Depth/Stencil Conversion Path: The depth/stencil surface-to-texture conversion now supports an alternative path that bypasses compute shaders, allowing for more flexible and potentially more efficient handling of depth/stencil data.
• Refined Error Tracing for Compatibility: The logging for surface-to-texture compatibility failures has been moved from the compatibility check function to the texture creation function, and is now more specific, only triggering for color surfaces that fail the new compatibility checks.

Changelog

• hw/xbox/nv2a/pgraph/vk/texture.c
  • Removed an unimplemented assertion in copy_zeta_surface_to_texture.
  • Refactored depth/stencil packing logic to be conditional based on use_compute_to_convert_depth_stencil.
  • Introduced a new helper function vk_format_texel_size for Vulkan format texel size determination.
  • Rewrote check_surface_to_texture_compatiblity to use a more generic format matching approach.
  • Relocated the trace_nv2a_pgraph_surface_texture_compat_failed call to create_texture with a specific condition.

Activity

• No specific human activity (comments, reviews) has been recorded for this pull request yet.

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[gemini-code-assist]

Code Review

This pull request aims to relax and simplify surface-to-texture constraints, which can improve performance in some cases. The changes primarily involve simplifying the compatibility check between surfaces and textures and adding a more direct copy path for depth/stencil surfaces that do not require format conversion via a compute shader. While the overall direction is good, I've identified a critical issue in the new compatibility check logic that could lead to invalid Vulkan API calls. My review includes a detailed comment on this issue, which remains relevant as originally stated.

[Copilot]

Pull request overview

This PR optimizes the surface-to-texture copy path in the NV2A Vulkan renderer by relaxing format compatibility constraints and adding a fast path for depth surfaces that don't require compute shader conversion.

Changes:

• Removed assertion that forced all depth-surface-to-texture copies to use compute shader conversion
• Added conditional logic to use direct buffer transfer when compute conversion is unnecessary
• Simplified surface-to-texture compatibility checking to compare texel sizes rather than explicit format pairs
• Added vk_format_texel_size() helper function to determine format sizes

[Triticum0]

Improves performance on fireblade
0.8.49

Pr