How Rendering Mode (Direct3D 11, Direct3D 10, Vulkan, OpenGL) works in ClientAppSettings.json
Switches the graphics API used by RobloxPlayerBeta.exe to lower CPU driver overhead or fix GPU driver crashes.
When you adjust **Engine Settings → Rendering mode** inside Bloxstrap, the bootstrapper writes `FFlagDebugGraphicsPreferD3D11 / PreferVulkan` into `ClientSettings\ClientAppSettings.json` before `RobloxPlayerBeta.exe` initializes its renderer.
Recommended values and stability tips
- **Accepted values:** `Direct3D 11 (default), Vulkan, Direct3D 10, OpenGL`. Stick to the built-in GUI preset under Engine Settings unless you are testing a specific JSON override.
- **Resetting:** If a custom value causes visual artifacts or a startup crash, use Reset FastFlags to default.
- **Installer:** Download the latest Windows build of Bloxstrap from /download.
Frequently asked questions
What FastFlag does "Rendering Mode (Direct3D 11, Direct3D 10, Vulkan, OpenGL)" control?
It manages `FFlagDebugGraphicsPreferD3D11 / PreferVulkan` inside `ClientAppSettings.json`, accessible directly via **Engine Settings → Rendering mode**.
Will this setting reset when Roblox updates?
No. Bloxstrap rewrites `ClientAppSettings.json` into the new Roblox version folder on every launch.