To improve rendering performance, we attach an OpenGLContext like this:
openGLContext.attachTo ( *getTopLevelComponent () );
within our constructor for the PluginAudioEditor.
If we do that, our plugin is displayed incorrectly, with the graphics scaled up (probably by my monitor scale-factor of 150%) from the bottom-left corner upwards. Mouse interaction is visibly offset by a large amount.
If we don’t attach the OpenGLContext, everything renders correctly.
This does NOT happen in stand-alone mode, only when loaded as a VST2 or VST3 in Cubase 10 (Windows 64-bit). Haven’t tested other plugin formats.
When changing my desktop scale to 100%, everything works correctly.