GPU(graphics processing unit) acceleration is available from version 2.0
The new engine uses Shaders and the performance directly depends on the graphics card power.
The greatest performance gain is noticeable when painting with large brushes of “Custom forms” with little spacing fixation. The increase is up to 100 times compared to the previous versions.
However, the brushes of small sizes in some cases can be even slower. Therefore we added the possibility to enable and disable the GPU-engine for every single brush.
In the top right corner, there is a “GPU” button, which can be used when you want to disable the GPU-engine temporarily, but it does not free the video memory. In order to fully disable the GPU-engine use Menu File->Options->OpenGL
With bristle brushes, the GPU-engine works a bit differently. The generation of the bristles and the result of a drawing are different from the usual bristle brush, so the new engine is disabled by default for all bristle brushes. The best usage of the engine is for large round brushes without size dynamics.
GPU-engine for bristle brushes requires the support for the OpenGL 4.3 (Nvidia GTX 660 and above), while OSX does not support OpenGL 4.3.
With Alt+j you can enable an experimental graphic mode (Windows only), in which all the calculations are done by the graphics card. However, the upper layers are not shown in this mode. Experimental mode is best suited for the hugest brushes and the symmetry mode.
The GPU-engine uses more video memory. 1 Mpix = 16mb of video memory. For example, the canvas size 5000х5000 (25Mpix) will take up 400 megabytes of VRAM more.