VulkanCompat

VulkanCompat

A client-side Fabric mod that makes Minecraft's Vulkan renderer run on older GPUs and drivers that do not support VK_KHR_dynamic_rendering.

Why?

Minecraft's Vulkan renderer relies on the VK_KHR_dynamic_rendering extension for drawing. Many older GPUs and drivers (especially on Linux or older Windows drivers) do not support this extension.

Without this mod, the game still opens but the Vulkan renderer fails to start with an error like this:

[Render thread/WARN]: Device [NVIDIA GeForce GT 740] does not support required extensions, missing: [VK_KHR_dynamic_rendering]
[Render thread/WARN]: Device [NVIDIA GeForce GT 740] does not have required feature [dynamicRendering]
[Render thread/ERROR]: Failed to create backend Vulkan
com.mojang.blaze3d.systems.BackendCreationException: Device missing capabilities
    at knot//com.mojang.blaze3d.vulkan.VulkanBackend.throwForMissingRequrements(VulkanBackend.java:404)
    at knot//com.mojang.blaze3d.vulkan.VulkanBackend.findPhysicalDevice(VulkanBackend.java:261)
    at knot//com.mojang.blaze3d.vulkan.VulkanBackend.createDevice(VulkanBackend.java:149)
    at knot//net.minecraft.client.Minecraft.<init>(Minecraft.java:515)
    at knot//net.minecraft.client.main.Main.main(Main.java:278)
    at net.fabricmc.loader.impl.game.minecraft.MinecraftGameProvider.launch(MinecraftGameProvider.java:514)
    at net.fabricmc.loader.impl.launch.knot.Knot.launch(Knot.java:72)
    at net.fabricmc.loader.impl.launch.knot.KnotClient.main(KnotClient.java:23)
    at org.prismlauncher.launcher.impl.StandardLauncher.launch(StandardLauncher.java:115)
    at org.prismlauncher.EntryPoint.listen(EntryPoint.java:129)
    at org.prismlauncher.EntryPoint.main(EntryPoint.java:70)

VulkanCompat translates the renderer's dynamic rendering calls into the classic, universally supported render pass API (vkCmdBeginRenderPass / vkCmdEndRenderPass), so the Vulkan renderer works on hardware without the extension.

Features

• Replaces vkCmdBeginRenderingKHR / vkCmdEndRenderingKHR with legacy render passes
• Replaces vkCreateGraphicsPipelines calls that use VK_KHR_dynamic_rendering pipelines with compatible render-pass-based pipelines
• Caches render passes and framebuffers to avoid performance loss
• Works automatically — no configuration needed, always active
• Uses the native vkCmdBeginRenderPass / vkCmdEndRenderPass when dynamic rendering is supported (no interference)
• Client-side only, lightweight

How it works

When a driver does not advertise VK_KHR_dynamic_rendering:

• The renderer is allowed to initialize without the extension (VK_KHR_dynamic_rendering is stripped from the required device extensions and features)
• Every render pass drawn with vkCmdBeginRenderingKHR is converted into a legacy render pass + framebuffer and recorded with vkCmdBeginRenderPass
• Pipeline compilation that references dynamic rendering structures is rewritten to use the equivalent classic render pass layout

When the driver does support dynamic rendering, the mod does nothing and the game behaves exactly as vanilla.

Compatibility

• Works with any GPU that supports Vulkan 1.2+ (which is practically all Vulkan-capable GPUs)
• GPU-specific drivers that lack VK_KHR_dynamic_rendering (e.g. older Intel, AMD, NVIDIA drivers; some Wine/Proton environments) benefit the most
• Client-side only; safe for singleplayer and multiplayer

[Render thread/WARN]: Device [NVIDIA GeForce GT 740] does not support required extensions, missing: [VK_KHR_dynamic_rendering]
[Render thread/WARN]: Device [NVIDIA GeForce GT 740] does not have required feature [dynamicRendering]
[Render thread/ERROR]: Failed to create backend Vulkan
com.mojang.blaze3d.systems.BackendCreationException: Device missing capabilities
    at knot//com.mojang.blaze3d.vulkan.VulkanBackend.throwForMissingRequrements(VulkanBackend.java:404)
    at knot//com.mojang.blaze3d.vulkan.VulkanBackend.findPhysicalDevice(VulkanBackend.java:261)
    at knot//com.mojang.blaze3d.vulkan.VulkanBackend.createDevice(VulkanBackend.java:149)
    at knot//net.minecraft.client.Minecraft.<init>(Minecraft.java:515)
    at knot//net.minecraft.client.main.Main.main(Main.java:278)
    at net.fabricmc.loader.impl.game.minecraft.MinecraftGameProvider.launch(MinecraftGameProvider.java:514)
    at net.fabricmc.loader.impl.launch.knot.Knot.launch(Knot.java:72)
    at net.fabricmc.loader.impl.launch.knot.KnotClient.main(KnotClient.java:23)
    at org.prismlauncher.launcher.impl.StandardLauncher.launch(StandardLauncher.java:115)
    at org.prismlauncher.EntryPoint.listen(EntryPoint.java:129)
    at org.prismlauncher.EntryPoint.main(EntryPoint.java:70)