7.10: Moving the Worm
- Page ID
- 14562
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# move the worm by adding a segment in the direction it is moving
if direction == UP:
newHead = {'x': wormCoords[HEAD]['x'], 'y': wormCoords[HEAD]['y'] - 1}
elif direction == DOWN:
newHead = {'x': wormCoords[HEAD]['x'], 'y': wormCoords[HEAD]['y'] + 1}
elif direction == LEFT:
newHead = {'x': wormCoords[HEAD]['x'] - 1, 'y': wormCoords[HEAD]['y']}
elif direction == RIGHT:
newHead = {'x': wormCoords[HEAD]['x'] + 1, 'y': wormCoords[HEAD]['y']}
wormCoords.insert(0, newHead)
To move the worm, we add a new body segment to the beginning of the wormCoords list. Because the body segment is being added to the beginning of the list, it will become the new head. The coordinates of the new head will be right next to the old head’s coordinates. Whether 1 is added or subtracted from either the X or Y coordinate depends on the direction the worm was going.
This new head segment is added to wormCoords with the insert() list method on line 10 [100].