Slower spin for sphere - GameCreators Forum

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Nickydude

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Posted: 17th Aug 2008 02:16

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I have the following that spins a sphere:

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REM Project: OuterSpace
REM Created: 16/08/2008 21:15:28
REM
REM ***** Main Source File *****
REM

Rem Set screen resolution
set display mode 1024,768,32

sync rate 60

rem Load up space image and show it
load image "images/space.jpg", 100
load image "images/lavacracks.jpg",101

make object plain 1,30,20
texture object 1,100
xrotate object 1,-10

make object sphere 2,10,100,100
`scale object 2,20,20,20
texture object 2,101
position object 2,8,5,4
scale object texture 2,4,4

rot = 1
`text 10,10,str$(object position x(2))
`text 10,20,str$(object position y(2))
`text 10,30,str$(object position z(2))
do
   yrotate object 2,rot
   if rot = 360 then rot = 1
   inc rot
loop

How do I make the sphere spin slower?

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TDK

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Posted: 17th Aug 2008 02:40

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+ Code Snippet

rot# = 0.1
do
  yrotate object 2,WrapValue(Object Angle Y(2)+rot#)
loop

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Nickydude

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Posted: 17th Aug 2008 12:51

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Thanks TDK. I've just got DBP a few days ago and still trying to get my head around it, I've compiled your tutorials into a document ready to print out.

Could you possibly explain exactly what the 'yrotate' line does? I have a general idea from the help files but would like to know so I can study it and keep it for future reference.

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Terrorist Zero

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Posted: 17th Aug 2008 18:06 Edited at: 17th Aug 2008 18:07

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The "yrotate object" function sets the desired object to a specific angle (e.g. "yrotate object 2,256" would set the angle of the object to 256 degrees).

Concentrating on the values inside the WrapValue() brackets we're finding out the current angle of the object on the Y axis and adding 0.1 to that value to give us the new angle the object is to be rotated to.

The WrapValue() function itself makes sure that the values inside the brackets don't add up to more than 360 (because it's just impractical to have an object have a rotational angle of more than 360), therefore once the value hits, lets say 361, then the WrapValue() function automatically returns it as a 1.
380 will return 20, 451 will return 91, and so forth...

Overall what the line is doing is telling object 2 to rotate on its Y axis to an angle 0.1 degrees greater than the previous time that line was called, but also to keep things simple by keeping the value between 0 and 360.

Hope that helped a little....