image

I'm not sure if this really deserves to be called a coordinate system (because we never convert between it and any other system). However, I include it here for completeness.

When setting up image resources (Pose and Graphic), we set the location of the pin relative to the top left corner of the Pose or Graphic. They are measured in pixels (real ones, not the logical pixels used by the window coordinates.

Even though world coordinate have the Y axis pointing upwards, the top left was chosen because image editor use the top left for their coordinates.