The height of the canvas.
The grid size.
The canvas rectangle.
The X coordinate of the scene rectangle within the larger canvas.
The Y coordinate of the scene rectangle within the larger canvas.
The width of the scene.
The height of the scene.
The scene rectangle.
The number of distance units in a single grid space.
The factor to convert distance units to pixels.
The units of distance.
The aspect ratio of the scene rectangle.
The length of the longest line that can be drawn on the canvas.
The number of grid rows on the canvas.
The number of grid columns on the canvas.
The width of the canvas.