move() actual coordinates is wrong #11
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- By doing relative move() step after step, trigonometric computation would accumulate floating-point inaccuracies along the loop - x/centerx were conflated leading to move() being rect.width/2 inferior to the expectation (same for y/centery) - This was encounterd (and can be reproduced) using: ``` robot.penDown() robot.rotate(45) robot.move(DISTANCE) robot.rotate(-90) robot.move(DISTANCE) robot.rotate(-135) robot.move(DISTANCE * math.sqrt(2)) ``` Expected: The robot is back exactly its starting point. Actual: It's not because both move(DISTANCE) were actually less than DISTANCE.
drzraf
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Add a small fix for Python3 / latest pygame version which require an integer to be passed to
move()but more importantly, fixes a (dx/dy) computation error inmove()Example:
Green points added for convenience to show the true place the robot should have moved to (based on correct
math.cos(math.radians(self.heading)) * distancecalculation between start and end points) [omit the left-most green point]Actual:
As you can see,
move()is shorter than what it should be due to a confusion between rect's(x, y)and(centerx, centery). The fact thatmove()does trigonometric computation in a loop adds up inaccuracy to the error.Expected (and using present PR):
