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Start reading these solutions in the Ball sprite.
1.OP.3.A (Take It Further)
We check X POSITION rather than TOUCHING EDGE because it's only the /right/ edge that loses a point.Paddle
51.OP.3.1: The mathematics of reflection.
Ideally, we'd like students to understand that the formula
new direction = - old direction
isn't a special case for a paddle on the right, with the ball approaching from the left. The same formula applies if the paddle is on the left. (And that will be important if they do the Take It Further adding a second paddle.) But it /is/ a special case for a /vertical/ paddle. If the paddle were horizontal, at the top or bottom of the stage (as in a Breakout game), the formula would be
new direction = 180 - old direction.
It matters that our direction measurement is clockwise from north. That means that a vertical paddle points toward direction 0 degrees. If we measured directions with 0 degrees = East, as mathematicians do, then it would be the horizontal paddle that simply negates the direction.
For students who've studied trig, they should be able to figure out a formula for bouncing off a diagonal paddle of any slope!Now go back to the Paddle sprite for 1.OP.3.3, then back here for 1.OP.3.4.
TIF BTIF C
Replace the three scripts above
with this one:
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