Render and GPU troubleshooting¶
Most rendering complaints come from one of: wrong backend, broken driver, color-management mismatch, or low VRAM.
Identify the backend¶
Help > About > GPU shows the active wgpu backend:
The Designer's default backend picker prefers, in order: Metal (macOS), DX12 (Windows), Vulkan (Linux), then OpenGL, then CPU.
Force a different backend¶
Values: metal, dx12, vulkan, gl, cpu.
Useful when:
- The default backend has a driver bug on your machine.
- You want to benchmark.
- You are debugging an OS-specific rendering issue.
Flicker / corruption¶
Symptoms: brief black flashes, garbled text, incorrect colors.
Try:
- Update graphics drivers (NVIDIA / AMD / Intel).
- Switch backend (force Vulkan on Linux if Wayland's compositor is buggy; force DX12 on Windows if Vulkan is misbehaving).
- Disable HDR on the active display.
- Lower the active monitor refresh rate temporarily.
Slow renders¶
If Production or Final quality presets take dramatically
longer than the render quality table
predicts:
- Confirm GPU compute path is active (
elysium doctorshows "GPU compute: yes"). - Reduce IBL resolution (
Preferences > Rendering > IBL Resolution). - Disable adaptive sampling if your scene has very stable variance.
Color looks wrong¶
The most common color complaints:
| Symptom | Fix |
|---|---|
| Textures look washed out | Verify their Input Space in the Properties pane (should be sRGB for albedos) |
| Iridescence flat / dim | Switch to Textured + Lit (7) and add a directional light |
| Output on web looks different than Designer | The Designer's output color space is sRGB by default; verify in Rendering > Color Space |
See Color management.
Out of memory¶
| Symptom | Fix |
|---|---|
| "Texture allocation failed" toast | Lower Preferences > Rendering > Texture Budget |
| Crash after long brushing session | View > Flatten Brush History |
| Renders fail above 2K resolution | The GPU compute path needs ~4 * w * h * 4 bytes free VRAM; CPU path tracer takes about half |
Tablet pressure not registering¶
See Touch and pen input.
Quick checks:
Help > Tablet Diagnostics: does pressure show?- macOS: System Settings > Privacy > Accessibility: is the Designer in the list?
- Windows: latest driver from the tablet vendor's site (not just Windows Update).
- Linux:
libinput list-devices | grep -A20 tabletshows the axes.
Linux Wayland¶
Wayland support is solid on KDE Plasma 6 and GNOME 46+. Older Sway and Hyprland builds may not honor hit-test paths or window-move correctly. Workarounds:
- Run under XWayland (
WAYLAND_DISPLAY= elysium-designer). - Update to the latest compositor.