Code archives/3D Graphics - Effects/Automatic Starfield generator
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It's a simple function set that I made a while back to help me get an easy to maintain starfield. Every frame, you call AnimateStarfield(). You can put some parms to adjust exactly where you want it to be. Usually your x and z are the same as where your view is. The starfield always go in the same direction. I didn't make it too advanced. And there's a function to delete the starfield, of course. | |||||
; FILENAME: func_stars.bb ;---------------------------------------------------------------------------------------- ; starfield management ;---------------------------------------------------------------------------------------- ; Define the type for each stars in a starfield Type star_info Field ptr Field xpos# Field ypos# Field zpos# Field velocity# End Type Global star_count% = 0 Function AnimateStarfield(x#=0,y#=0,z#=0,occ%=6) Local overlap_x# = Rnd(0, 2500.0) Local overlap_z# = Rnd(0, 5000.0) If Rand(1,occ%) = occ% Then AddStar(x#, y#, z#, overlap_x#, overlap_z#) For star.star_info = Each star_info star\xpos# = star\xpos# + star\velocity# If (star\xpos#) > (x# + overlap_x# + 2500.0) Then FreeEntity star\ptr Delete star.star_info star_count% = star_count% - 1 Else ;PositionMesh star\ptr, star\velocity#, 0, 0 PositionEntity star\ptr, star\xpos#, star\ypos#, star\zpos# EndIf Next End Function Function DeleteAllStars() For star.star_info = Each star_info FreeEntity star\ptr Delete star.star_info Next star_count% = 0 End Function Function AddStar(xref#, yref#, zref#, overlap_x#, overlap_z#) Local starsize# = Rnd(0.5,2.01) Local speed# = Rnd(2.0,8.0) If starsize# > 2 Then starsize# = 18.0 - speed# EndIf star.star_info = New star_info ; star\ptr = make_star (2 + Int starsize#) star\ptr = CreateSphere(2 + Int starsize#) star\xpos# = xref# - overlap_x# - 2500.0 star\zpos# = zref# - overlap_z# + 2500.0 star\ypos# = 650.0 + Rnd(0, 350.0) star\velocity# = speed# ; EntityTexture star\ptr, ptr_texture(127),0,1 EntityBlend star\ptr, 3 EntityFX star\ptr, 1 ScaleEntity star\ptr, starsize#, starsize#, starsize# EntityColor star\ptr, 255, 255, 255 star_count% = star_count% + 1 ; PositionEntity star\ptr, star\xpos#, star\ypos#, star\zpos# End Function |
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And an example of how to use the functions please? |
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Every frame, you call AnimateStarfield(). You can put some parms to adjust exactly where you want it to be. Then call DeleteAllStars() to delete the starfield (useful when you leave the "in game" scene). CODE EXAMPLE: Do not forget to have the include file in the same directory as this test. |
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