Problem With Pong - GameCreators Forum

Author

Message

Livinit

18

Years of Service

User Offline

Joined: 21st Aug 2006

Location: anywhere

Posted: 21st Aug 2006 21:02

Link

I followed the tutorial for pong, but I tweaked it a bit by adding in different collision code from another tutorial for DB. Please tell me how, using this code, how to get the ball to bounce away from the paddle, because the ball will only bounce frantically in one place. Here is the code:

Sync On
Sync Rate 30
Backdrop on
Color Backdrop RGB(0,150,0)
Hide Mouse

REM Make Boxes for boundaries
REM Vert. 1
Make object box 4,1,1,27
Color object 4,RGB(0,100,0)
Position object 4,-15,0,0
REM Vert. 2
Make object box 5,1,1,27
Color object 5,RGB(0,100,0)
Position object 5,15,0,0
REM Horiz. 1
Make Object Box 6,30,1,1
Color Object 6,RGB(0,100,0)
Position object 6,0,0,11
REM Horiz. 2
Make Object Box 7,30,1,1
Color Object 7,RGB(0,100,0)
Position object 7,0,0,-11

REM make player paddle
Make Object Box 1,1,1,3
Color Object 1,RGB(0,0,225)
Position Object 1,-10,0,0

REM make opponent paddle
Make Object box 2,1,1,3
Color Object 2,RGB(225,0,0)
Position Object 2,10,0,0

REM Make Ball
Make Object sphere 3,2
Position Object 3,0,0,0
Color OBject 3,RGB(225,225,225)

REM Main Loop
Do

REM position Camera
Position Camera 0,17,0
Point Camera 0,0,0
Rotate Camera 90,0,0

REM Store Player's, Ball's, and Opponent's Positions
Y#=Object Position y(1)
X#=Object Position x(1)
Z#=Object Position z(1)
X2#=Object Position x(2)
Y2#=Object Position y(2)
Z2#=Object Position z(2)
Y3#=Object position y(3)
SPD#=0.5
X3#=newxvalue(X3#,a3#,SPD#)
Z3#=newzvalue(Z3#,a3#,SPD#)
a3#=Object Angle y(3)
a3#=-90
REM Store Player's Controls
If Upkey()=1 AND Y#<2 then move object 1,Y#+1
If Downkey()=1 AND Y#>-2 then move object 1,Y#-1

REM Collisions
REM Player
Set Object Collision to Boxes 1
If object collision(1,0)>1 then position object 1,X#,Y#,Z#
REM Ball
Set Object Collision to Spheres 1
If object collision(1,0)>0 then a3#=360-a3#
a3#=wrapvalue(a3#)

REM Opponent
Set object collision to boxes 2
If object Collision(2,0)>1 then position object 2,X2#,Y2#,Z2#

Position Object 3,X3#,0,Z3#
yrotate object 3,a3#

REM Refresh Screen
Sync

Loop

+ Code Snippet

Sync On
Sync Rate 30
Backdrop on
Color Backdrop RGB(0,150,0)
Hide Mouse

REM Make Boxes for boundaries
REM Vert. 1
Make object box 4,1,1,27
Color object 4,RGB(0,100,0)
Position object 4,-15,0,0
REM Vert. 2
Make object box 5,1,1,27
Color object 5,RGB(0,100,0)
Position object 5,15,0,0
REM Horiz. 1
Make Object Box 6,30,1,1
Color Object 6,RGB(0,100,0)
Position object 6,0,0,11
REM Horiz. 2
Make Object Box 7,30,1,1
Color Object 7,RGB(0,100,0)
Position object 7,0,0,-11

REM make player paddle
Make Object Box 1,1,1,3
Color Object 1,RGB(0,0,225)
Position Object 1,-10,0,0

REM make opponent paddle
Make Object box 2,1,1,3
Color Object 2,RGB(225,0,0)
Position Object 2,10,0,0

REM Make Ball
Make Object sphere 3,2
Position Object 3,0,0,0
Color OBject 3,RGB(225,225,225)

REM Main Loop
Do

REM position Camera
Position Camera 0,17,0
Point Camera 0,0,0
Rotate Camera 90,0,0

REM Store Player's, Ball's, and Opponent's Positions
Y#=Object Position y(1)
X#=Object Position x(1)
Z#=Object Position z(1)
X2#=Object Position x(2)
Y2#=Object Position y(2)
Z2#=Object Position z(2)
Y3#=Object position y(3)
SPD#=0.5
X3#=newxvalue(X3#,a3#,SPD#)
Z3#=newzvalue(Z3#,a3#,SPD#)
a3#=Object Angle y(3)
a3#=-90
REM Store Player's Controls
If Upkey()=1 AND Y#<2 then move object 1,Y#+1
If Downkey()=1 AND Y#>-2 then move object 1,Y#-1

REM Collisions
REM Player
Set Object Collision to Boxes 1
If object collision(1,0)>1 then position object 1,X#,Y#,Z#
REM Ball
Set Object Collision to Spheres 1
If object collision(1,0)>0 then a3#=360-a3#
a3#=wrapvalue(a3#)

REM Opponent
Set object collision to boxes 2
If object Collision(2,0)>1 then position object 2,X2#,Y2#,Z2#

Position Object 3,X3#,0,Z3#
yrotate object 3,a3#


REM Refresh Screen
Sync

Loop

Thank you for any help you can give me.

hmmmmmm.....

Back to top

Profile PM Email

CreamPie

18

Years of Service

User Offline

Joined: 20th Jul 2006

Location:

Posted: 22nd Aug 2006 01:00

Link

Livinit,

The ball is at the same location that the collision was detected, when and after the collision is detected. Therefore, you get a loop of collision detection, which makes the ball to act frantically, because it never has a chance to escape the collision point.

One way to fix this would be to record the ball's cordinate positions to 'old position' variables, somewhere at the end of your code. Theses values will be used on the next loop to reposition the ball where it was right before it collided with the paddle. Currently, you are repositioning the ball at the collision point, which ultimatelly can cause it to run a collision loop.

EX:

+ Code Snippet

X3#=newxvalue(X3#,a3#,SPD#)
Z3#=newzvalue(Z3#,a3#,SPD#)

REM record old positions to reposition ball correctly in event of collision
oldx# = X3#
oldz# = Z3#

When collision happens reposition the ball at the coordinates it was before it collided with the paddle:

+ Code Snippet

X3# = oldx#
Z3# = oldz#

Hope this helps.

>-Formerly known as NanoBrain-<

Back to top

Profile PM Email

Livinit

18

Years of Service

User Offline

Joined: 21st Aug 2006

Location: anywhere

Posted: 22nd Aug 2006 01:49

Link

Thx

Again I have tried but failed, could you edit my code so the bouncing would work, because I am seriously losing hair,thx again for your help

hmmmmmm.....

Back to top

Profile PM Email

Kendor

21

Years of Service

User Offline

Joined: 31st Jan 2003

Location: Malta

Posted: 27th Aug 2006 17:31 Edited at: 27th Aug 2006 17:32

Link

Here you go, this should work.

- Removed collision set-up and constants from loop
- changed position of some commands for a correct program flow.

Sync On
Sync Rate 30
Backdrop on
Color Backdrop RGB(0,150,0)
Hide Mouse

REM Make Boxes for boundaries
REM Vert. 1
Make object box 4,1,1,27
Color object 4,RGB(0,100,0)
Position object 4,-15,0,0
REM Vert. 2
Make object box 5,1,1,27
Color object 5,RGB(0,100,0)
Position object 5,15,0,0
REM Horiz. 1
Make Object Box 6,30,1,1
Color Object 6,RGB(0,100,0)
Position object 6,0,0,11
REM Horiz. 2
Make Object Box 7,30,1,1
Color Object 7,RGB(0,100,0)
Position object 7,0,0,-11

REM make player paddle
Make Object Box 1,1,1,3
Color Object 1,RGB(0,0,225)
Position Object 1,-10,0,0

REM make opponent paddle
Make Object box 2,1,1,3
Color Object 2,RGB(225,0,0)
Position Object 2,10,0,0

REM Make Ball
Make Object sphere 3,2
Position Object 3,0,0,0
Color OBject 3,RGB(225,225,225)

` =====  removed from inside of loop ===== 
Set object collision to boxes 2
Set Object Collision to Boxes 1
Set Object Collision to Spheres 3
a3#=-90
SPD#=0.5

REM Main Loop
Do

REM position Camera
Position Camera 0,17,0
Point Camera 0,0,0
Rotate Camera 90,0,0

REM Store Player's, Ball's, and Opponent's Positions
Y#=Object Position y(1)
X#=Object Position x(1)
Z#=Object Position z(1)
X2#=Object Position x(2)
Y2#=Object Position y(2)
Z2#=Object Position z(2)
X3#=Object Position x(3)
Y3#=Object Position y(3)
Z3#=Object Position z(3)
`removed =====  a3#=Object Angle y(3) =====

REM Store Player's Controls
If Upkey()=1 AND Y#<2 then move object 1,Y#+1
If Downkey()=1 AND Y#>-2 then move object 1,Y#-1

REM Collisions
REM Player
If object collision(1,0)>1 then position object 1,X#,Y#,Z#

REM ===== check the ball collision =====
If object collision(3,0)>0 then a3#=a3#-180

REM Opponent
If object Collision(2,0)>1 then position object 2,X2#,Y2#,Z2#

a3#=wrapvalue(a3#)
`===== moved to calculate using new angle ===== 
X3#=newxvalue(X3#,a3#,SPD#)
Z3#=newzvalue(Z3#,a3#,SPD#)

Position Object 3,X3#,0,Z3#
yrotate object 3,a3#

REM Refresh Screen
Sync

Loop

+ Code Snippet

Sync On
Sync Rate 30
Backdrop on
Color Backdrop RGB(0,150,0)
Hide Mouse

REM Make Boxes for boundaries
REM Vert. 1
Make object box 4,1,1,27
Color object 4,RGB(0,100,0)
Position object 4,-15,0,0
REM Vert. 2
Make object box 5,1,1,27
Color object 5,RGB(0,100,0)
Position object 5,15,0,0
REM Horiz. 1
Make Object Box 6,30,1,1
Color Object 6,RGB(0,100,0)
Position object 6,0,0,11
REM Horiz. 2
Make Object Box 7,30,1,1
Color Object 7,RGB(0,100,0)
Position object 7,0,0,-11

REM make player paddle
Make Object Box 1,1,1,3
Color Object 1,RGB(0,0,225)
Position Object 1,-10,0,0

REM make opponent paddle
Make Object box 2,1,1,3
Color Object 2,RGB(225,0,0)
Position Object 2,10,0,0

REM Make Ball
Make Object sphere 3,2
Position Object 3,0,0,0
Color OBject 3,RGB(225,225,225)


` =====  removed from inside of loop ===== 
Set object collision to boxes 2
Set Object Collision to Boxes 1
Set Object Collision to Spheres 3
a3#=-90
SPD#=0.5


REM Main Loop
Do

REM position Camera
Position Camera 0,17,0
Point Camera 0,0,0
Rotate Camera 90,0,0

REM Store Player's, Ball's, and Opponent's Positions
Y#=Object Position y(1)
X#=Object Position x(1)
Z#=Object Position z(1)
X2#=Object Position x(2)
Y2#=Object Position y(2)
Z2#=Object Position z(2)
X3#=Object Position x(3)
Y3#=Object Position y(3)
Z3#=Object Position z(3)
`removed =====  a3#=Object Angle y(3) ===== 

REM Store Player's Controls
If Upkey()=1 AND Y#<2 then move object 1,Y#+1
If Downkey()=1 AND Y#>-2 then move object 1,Y#-1

REM Collisions
REM Player
If object collision(1,0)>1 then position object 1,X#,Y#,Z#

REM ===== check the ball collision =====
If object collision(3,0)>0 then a3#=a3#-180

REM Opponent
If object Collision(2,0)>1 then position object 2,X2#,Y2#,Z2#


a3#=wrapvalue(a3#)
`===== moved to calculate using new angle ===== 
X3#=newxvalue(X3#,a3#,SPD#)
Z3#=newzvalue(Z3#,a3#,SPD#)



Position Object 3,X3#,0,Z3#
yrotate object 3,a3#


REM Refresh Screen
Sync

Loop

Home computers are being called upon to perform many new functions, including the consumption of homework formerly eaten by the dog.

Back to top

Profile PM Email Website

Sorry your browser is not supported!

Newcomers DBPro Corner / Problem With Pong