;***********************************************
;* Cannonball physics *
;* *
;* By *
;* *
;* Jeppe Nielsen *
;* *
;* www.dahlsgaards.dk/blitz *
;* *
;* nielsen_jeppe@hotmail.com *
;* *
;***********************************************
Type obj
Field mass#,speed#
Field x#,y#,sx#,sy#
End Type
Graphics 640,480,16,2
SetBuffer BackBuffer()
Global mass#=1,speed#=0,trust#=10,gravity#=0.05,windspeed#=0.04,windangle#=90
Global stx=320,sty=240,angle#,lastobj.obj
Global mx,my
Repeat
Cls
mx=MouseX()
my=MouseY()
trust#=Float(Sqr((stx-mx)^2+(sty-my)^2))/10
angle#=ATan2(my-sty,mx-stx)
Plot stx,sty
Line stx,sty,stx+30*Cos(angle),sty+30*Sin(angle)
Plot mx,my
Line 550,80,550+30*Cos(windangle),80+30*Sin(windangle)
Text 10,10,"Power :"+trust#
Text 10,20,"Angle :"+Int(angle#)
Text 10,30,"Obj mass :"+mass#
Text 450,10,"Wind speed :"+windspeed#
Text 450,20,"Wind angle :"+Int(windangle#)
If KeyDown(200) Then mass#=mass#+0.5
If KeyDown(208) Then mass#=mass#-0.5:If mass#<1 Then mass#=1
If lastobj<>Null Then Text 10,40,"Last obj speed :"+Str(Sqr(lastobj\sx#^2+lastobj\sy#^2))
updateall()
drawall()
If MouseDown(1) Then lastobj=createobj(mass#,stx,sty,trust#,angle)
dir=Int(Rnd(0,99))
If dir<5
windangle#=windangle#+1
If windangle#>359 Then windangle#=0
Else
windangle#=windangle#-1
If windangle#<0 Then windangle#=359
EndIf
Flip
Until KeyDown(1)
End
Function createobj.obj(mass#,x,y,inittrust#,angle)
o.obj=New obj
o\mass#=mass#
o\x=x
o\y=y
o\speed#=inittrust#/mass#
o\sx#=Cos(angle)*o\speed#
o\sy#=Sin(angle)*o\speed#
Return o
End Function
Function updateall()
windx#=windspeed#*Cos(windangle#)
windy#=windspeed#*Sin(windangle#)
For o.obj=Each obj
o\sx#=o\sx#+(windx#/o\mass#)
o\sy#=o\sy#+gravity#+(windy#/o\mass#)
o\x#=o\x#+o\sx#
o\y#=o\y#+o\sy#
If o\x<0 Or o\x>640 Or o\y<0 Or o\y>480 Then Delete o
Next
End Function
Function drawall()
For o.obj=Each obj
Oval o\x,o\y,o\mass,o\mass,0
Next
End Function |
