if <touching [paddle v] ?> then
turn ccw (180) degrees
end

if <touching [paddle1 v] ?> then
point towards [paddle1 v]
turn cw (180) degrees
end
if <touching [paddle2 v] ?> then
point towards [paddle2 v]
turn cw (180) degrees
end

ggenije2 wrote:

if <touching [paddle1 v] ?> then
point towards [paddle1 v]
turn cw (180) degrees
end
if <touching [paddle2 v] ?> then
point towards [paddle2 v]
turn cw (180) degrees
end

if <touching [Paddle] ?> then
point in direction ((x position) - ([x position] of [Paddle]))
end

Trixie987 wrote:

What about bouncing the ball. How would you bounce it without toching the edge and getting lower and lower?

Trixie987 wrote:

Trixie987 wrote:

What about bouncing the ball. How would you bounce it without toching the edge and getting lower and lower?

Actually forget that. I can't edit it anymore. But how would you skim it across the paddle?

Jlerpy wrote:

Wait, why can't you edit it any more?

bgvikings08 wrote:

Trixie987 wrote:

Trixie987 wrote:

What about bouncing the ball. How would you bounce it without toching the edge and getting lower and lower?

Actually forget that. I can't edit it anymore. But how would you skim it across the paddle?

I don't understand what you want. Im sorry…

repeat until <(direction) = [180]>
turn cw (5) degrees
end

Trixie987 wrote:

Actually forget that. I can't edit it anymore.

Trixie987 wrote:

Say the ball touched the edge. Instead of going the completely opposite way, how would you make it so the ball continues going forwards but the height changes. Like if you skim a rock it continues going forward but jumps up..

forever
change x by (x_velocity)
change y by (y_velocity)
end

forever
if <touching [paddle v] ?> then
set [y_velocity v] to ((0) - (y_velocity))  // and no change to x_velocity
end
end

RT_Borg wrote:

Hi Trixie987,

Trixie987 wrote:

Actually forget that. I can't edit it anymore.

Everyone, I'm pretty sure Trixie987 meant “edit the forum post any more”. New scratchers (like me and Trixie987) can only edit a post right after Submit.

Trixie987 wrote:

Say the ball touched the edge. Instead of going the completely opposite way, how would you make it so the ball continues going forwards but the height changes. Like if you skim a rock it continues going forward but jumps up..

Yes, you want it to bounce naturally, instead of reversing direction. That was my first thought when I saw the Pong tutorial too. It takes just a little more work, but isn't too bad.

The trick to what you want to do is to keep track of your own variables for “x_velocity” (horizontal speed) and “y_velocity” (vertical speed). In a movement loop (forever) you can move the ball by updating these:

forever
change x by (x_velocity)
change y by (y_velocity)
end

and elsewhere, change x_velocity or y_velocity when you hit walls or the paddle. (So not using “direction” or “if on edge, bounce” at all.)

There's fancy math and physics engines if you have weird shapes and angles, but for vertical and horizontal obstacles you don't need the fancy stuff.

You're thinking about the problem in exactly the right way when you say “the ball continues going forwards but the height changes”. To state the thought in terms of these variables: When you bounce off the paddle, you want the x_velocity to stay the same, but you want the y_velocity to to be the same speed in the opposite direction:

forever
if <touching [paddle v] ?> then
set [y_velocity v] to ((0) - (y_velocity))  // and no change to x_velocity
end
end

Because you're keeping track of your own variables for x_velocity and y_velocity, you won't want to just bounce off the top and edges of the screen (because “if on edge, bounce” won't update your x_velocity and y_velocity when the motion of the ball changes).

So you can put your own wall sprites on the top, left, right and bottom and reflect off them just like you do with the paddle.

Horizontal surfaces like top (and bottom if you don't just stop when it lands) are just like bouncing off a paddle. Vertical surfaces (left and right walls) are similar, but you want x_velocity to become - x_velocity and leave y_velocity unchanged.

I made a sample project that shows this technique: https://scratch.mit.edu/projects/690905887

I hope this helps. Happy to answer any questions.

- RT_Borg