bouncing with x, y velocities

MasterScratchC

I have a sprite with an x velocity and a y velocity variable, and when It hits the edge of the screen I need it to change the x and y velocities to make it appear it bounces off of the edge of the screen, similar to the if on edge, bounce block. how can I do this?

I can't use the direction variable, so i can't use the if on edge, bounce block

when green flag clicked
forever
change x by (x velocity)
change y by (y velocity)
if <touching [edge v] ?> then
do something to
end
end

define me
ask [do you like bananas?] and wait
if <(answer) = [yes]> then 
say (join [me too! ] (conversation about bananas)
else
if <(answer) = [no]> then
show list [why bananas are good v]
start discussion on (why bananas are good) ::sound
end
end

The_Imaginarium

when green flag clicked
forever
if <[180] < ([abs v] of (y position))> then
set [y velocity v] to ((0)-(y velocity))
end
if <[240]  < ([abs v] of (x position))> then
set [x velocity v] to ((0)-(x velocity))
end
change x by (x velocity)
change y by (y velocity)
end

Last edited by The_Imaginarium (Aug. 1, 2021 18:09:14)

awesome-llama

You can find which edge the sprite has touched and then change the x or y velocity relevant to that wall. If it is the side walls, make the x velocity opposite of what it was before

The specifics of this are up to you to decide since there are so many ways to solve it.

Example

when green flag clicked
forever
if <([abs v] of (x position)) > [240]> then
set [x velocity v] to ((0) - (x velocity))
end
if <([abs v] of (y position)) > [180]> then
set [y velocity v] to ((0) - (y velocity))
end
change x by (x velocity)
change y by (y velocity)
end

CompassesHelpMe

You need to fine tune the x and y values of the bounce to the size of your ball.

Last edited by CompassesHelpMe (Aug. 1, 2021 18:08:38)

yes

MasterScratchC

thank you! this worked perfectly

define me
ask [do you like bananas?] and wait
if <(answer) = [yes]> then 
say (join [me too! ] (conversation about bananas)
else
if <(answer) = [no]> then
show list [why bananas are good v]
start discussion on (why bananas are good) ::sound
end
end

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