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Sprites following an angle

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UltraPhoenix4Created:
UltraPhoenix4#1
Is is possible to make a sprite face a certain angle and then go forward along that angle? If so, how?
Perska#2
Use this code: 
SPEED#=2
ANGLE#=90
INC X#,SIN(RAD(ANGLE#))*SPEED#
INC Y#,COS(RAD(ANGLE#))*SPEED#
SPOFS 0, X#, Y#
SPROT 0, ANGLE#
The sprite should move to the right I think? SPEED# is the movement speed.
mystman12#3
Are angles in SmileBASIC calculated in degrees or radians? Or is there a way to select which it uses?
cujo1992#4
Are angles in SmileBASIC calculated in degrees or radians? Or is there a way to select which it uses?
The SIN and COS functions require radians (as do other trig functions). SPROT, on the other hand takes degrees. Perska's code is a nice example of converting from polar coordinates into Cartesian x-y. If you choose an angle for the sprite to go, however, you have to be careful about the y-direction. An angle of zero degrees will have COS (0) which should yield +1 sending the sprite DOWNWARD in screen coordinates. Similarly, selecting 45 degrees for the angle will send the sprite directly "southeast". In an application where I have similar code I used -COS(RAD(ANGLE)) to invert typical polar coordinates for the screen. In Perska's code sample one could use DEC instead of INC to achieve the same Y inversion (depending on your application).
snail_#5
In fact, SPROT only takes integers in degrees. Real numbers are truncated. It would be nice if they just settled on one format to use but hey, nothing's perfect.