Support QTransform

Is your feature request related to a problem? Please describe. I'm working on porting an existing PyQt project over to this framework. It includes a renderer for a custom animation format, which involves applying transformations to sprites including translation, rotation, scaling, etc. However, there is currently no support for QTransform and the corresponding QImage API.

This means I have to drop down out of this framework and switch to other libraries, then transfer the buffer to a QImage. This is a lot of headache compared to the equivalent Qt code, which is succinct.

Describe the solution you'd like Add support for QTransform and QImage.transformed

Describe alternatives you've considered I'm currently using a combination of the npm libraries sharp and transformation-matrix to compensate for the lack of this functionality.