Heya. This code is based on Tracer's 3ddotball.bb code that shipped with blitz3d. I'm trying to get a sphere of 2d stars to be rotated as if it was a 3d starfield. If you know what I mean. Here's the source. I just can't get it right.
I want to make it move as if each star were a sprite, and the camera was looking around.
Any help appreciated.
; *****************************
; * DEPTH COLORED 3D DOT BALL *
; *****************************
; * CODING BY TRACER *
; Z location.
; Arrays used by 3d code.
Dim star_points#(1500, 5)
Graphics 512,384,32,2
SetBuffer BackBuffer()
setup2dStarField()
HidePointer
; Loop till esc is pressed.
While Not KeyDown(1)
mx#=(MouseXSpeed()*0.2)
my#=(MouseYSpeed()*0.2)
MoveMouse GraphicsWidth()/2,GraphicsHeight()/2
update2DStarField(mx,my) ; Removes the mouse from fullscreen.
Flip ; Flip the screen.
Cls ; Clear the screen.
Wend
End
Function setup2dStarField(dots_in_ball=1500)
For t= 1 To dots_in_ball
xd# = Rnd(-90.0,90.0)
x0# = (Cos(xd) * 10.0) * (Cos(t) * 10.0)
y0# = (Cos(xd) * 10.0) * (Sin(t) * 10.0)
z0# = Sin(xd) * 100.0
star_points(t,1) = x0
star_points(t,2) = y0
star_points(t,3) = z0
star_points(t,4)=Rnd(10,150)
Next
star_points(0,0)=100
End Function
Function update2DStarField(x#,y#,dots_in_ball=1500)
star_points(0,1)=star_points(0,1)+y
star_points(0,2)=star_points(0,2)
star_points(0,3)=star_points(0,3)+x
gw=GraphicsWidth()
gh=GraphicsHeight()
distance#=star_points(0,0)
vx#=star_points(0,1)
vy#=star_points(0,2)
vz#=star_points(0,3)
For n = 1 To dots_in_ball
x3d# = star_points(n, 1)
y3d# = star_points(n, 2)
z3d# = star_points(n, 3)
ty# = ((y3d * Cos(vx#)) - (z3d * Sin(vx#)))
tz# = ((y3d * Sin(vx#)) + (z3d * Cos(vx#)))
tx# = ((x3d * Cos(vy#)) - (tz# * Sin(vy#)))
tz# = ((x3d * Sin(vy#)) + (tz# * Cos(vy#)))
ox# = tx#
tx# = ((tx# * Cos(vz#)) - (ty# * Sin(vz#)))
ty# = ((ox# * Sin(vz#)) + (ty# * Cos(vz#)))
nx# = Int(gw * (tx#) / (distance - (tz#))) + gh
ny# = Int(gh - (gw* ty#) / (distance - (tz#)))
Color star_points(n, 4),star_points(n, 4),star_points(n, 4)
Rect nx,ny,1,1
Next
End Function
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