Feature · GPU engine
Vulkan GPU Engine: Requirements and Speed
Solstice composites layers and paints pixel-brush strokes on the graphics card with Vulkan. What runs on the GPU, the supported hardware, and measured results.
The GPU engine is an ongoing rewrite of the image engine Solstice inherited from Krita. On RGBA 32-bit and 16-bit float documents it moves layer compositing, the canvas display, brush strokes, transforms and Gaussian Blur to the graphics card. Anything it does not support runs on the CPU as before. It is on by default and experimental.
Requirements
- GPU: NVIDIA Blackwell (GeForce RTX 50 series or RTX PRO Blackwell) with a current driver. Other GPUs are not supported yet; Solstice then works on the CPU.
- System: Windows 11, 64-bit, with Vulkan 1.3 and desktop OpenGL for the canvas (not ANGLE/Direct3D).
- Documents: RGBA 32-bit or 16-bit float. New documents use 32-bit float, and Solstice offers to convert other documents when they open.
What runs on the GPU
- Layer compositing and display, in every blend mode except Dissolve, Marker, Destination In/Atop and Divisive Modulo.
- The pixel brush in Buildup and Wash, with selections, alpha lock, mirror painting and masking brushes.
- Brush dabs: auto-brush tips, image tips (including imported Photoshop brushes) and pattern textures.
- Transform Tool: free transforms, Liquify and Puppet Warp, with results identical to the CPU.
- Gaussian Blur, also inside Unsharp Mask and Gaussian High Pass.
Other filters, perspective, warp, cage and mesh transforms, and the preview while editing a transform still run on the CPU.
Pen input to display
- 64 px Buildup3.6× faster
- 64 px Wash3.5× faster
- 256 px Buildup4.3× faster
- 256 px Wash4.0× faster
Measured to Qt's frame swap, not to light leaving the screen. Brush size and preset complexity can still make drawing lag behind input.
Engine operations
- Layer projection, 4096 × 4096, 16 layers4.5× faster
- Canvas data preparation, 4096 × 4096, 8 layers671× faster
- Transform Tool apply, scale + rotate, 2480 × 35088.2× faster
- Liquify apply, 20 strokes, 2480 × 35084.0× faster
- Gaussian Blur apply, radius 30, 2480 × 35083.1× faster
- Puppet Warp apply, 3 pins, 2480 × 35083.5× faster
These time single engine operations, not frame rates or overall performance. A complete short stroke with a small brush can still be faster on the CPU; large, textured, masked or mirrored strokes favor the GPU.
Turning it on or off
In Settings → Configure Solstice → Performance → General, under GPU Engine (Vulkan), check or uncheck the engine and Paint brush strokes on the GPU, then restart Solstice.