A cell at grid$[$i$,$ j$]$ is set to true if navigable, false otherwise. The first array dimension $($i

index$)$ is associated$/$aligned with the positive x axis of the canvas. The second array

dimension $($j index$)$ is associated$/$aligned with the positive y axis of the canvas. Note that

the j index is in the major axis $($memory contiguous axis$)$ of the grid$[]$ array for this

application