- Main-process interact instances for the selected OFX effect card
(create on selection change, describe, destroy on deselect/close),
coexisting with the render-worker plugin instances per the OFX
multi-instance model.
- Program viewer composites the interact's overlay: draw into a GL
FBO via gl_bridge, read back, straight-alpha 'over' composite onto
the displayed frame; cached and only re-rendered on frame/time/
viewport/instance change or plugin redraw requests.
- Event forwarding: picture-area pointer maps through the contain-fit
letterbox inverse to OFX pen coordinates (pen_motion/down/up);
Keystroke to OFX key symbols (ASCII, navigation, F1-F35) for
key_down/up; a 50ms idle pump; global shortcut consumption keeps
precedence.
- e2e with the real test plugin: lifecycle marker assertions, pen/key
event records, and macOS GL overlay compositing verified (265 tests
green incl. gpui_widgets viewer suite).