Coordinates

Graphics objects are described using double precision X and Y coordinates. The origin (0.0, 0.0) is the upper left corner of the image. X increases to the right, and Y increases going down.

Unlike many older graphics packages (for various languages), coordinates and dimensions in JavaFX are double precision variables. Ultimately, the individual pixels of an image are painted at discrete (x,y) locations, but that is a job of the graphics system.