Raycaster

Community Forums/Showcase/Raycaster

Noobody (Posted 2008) [#1]

Hey guys, in the last few weeks I was experimentating with the raycaster algorithm and this is what came out :D Raycasting is an alternative way to render 3D - sceneries, similar to raytracing; games like Wolfenstein 3D or Doom used it. Event though my implementation isn't really complex, it's still able to handle floor, ceilings, textured walls and sprites. Especially the sprites take quite long to render, since I couldn't figure out a fast visibility check. There are still bugs I couldn't fix yet. Sometimes rays fly through walls and things behind the wall are being rendered. Mocing with arrow keys, + and - on numpad to look up/down. You can use the code in your games, if you want to - even though I don't expect it :D You can download the file at http://www.noobody.org/BBP/Raycaster.rar PS: Please excuse my bad english - I'm still working on it ;) EDIT: Oh noes, I forgot the screenshots! EDIT2: Hrm, I can't figure out that part with the image- and url tags...

KillerX (Posted 2008) [#2]

Do it like this, but put a space between img and http: [imghttp://www.noobody.org/Data/Screenie.PNG] [imghttp://www.noobody.org/Data/Screenshot.PNG]

Noobody (Posted 2008) [#3]

Oh, thanks alot :D

Jesse (Posted 2008) [#4]

not bad! it is kind of slow for 320 x 200. isn't it? anyway.. just did a quick glance at your code and I think I fixed a couple of your errors: Const MAPSIZE = 16 Const GRIDSIZE = 64 Const GRIDSHIFTS = 6 Const GWIDTH = 320 Const GHEIGHT = 200 Const ANGLEOFVIEW = 60 Const CASTINGSTEP# = ANGLEOFVIEW/Float( GWIDTH ) Const TILES = 2 Const TEXTURESIZE = 64 Const SCALEFACTOR# = TEXTURESIZE/GRIDSIZE Const FLOORTILE = 2 Const CEILINGTILE = 2 Const HD = ( SCALEFACTOR# <> 1 ) Const CEILING = True Graphics GWIDTH, GHEIGHT, 32, 2 Global CamX# = 5*GRIDSIZE + GRIDSIZE/2, CamY# = 5*GRIDSIZE + GRIDSIZE/2, ProjectionDistance# = ( GWIDTH/2 )/Tan( ANGLEOFVIEW/2 ) Global CameraAngle = 270, PlayerHeight = 32, PlaneDisplacement Dim MapData( MAPSIZE - 1, MAPSIZE - 1 ) Dim TextureData( TILES*( TEXTURESIZE)*( TEXTURESIZE ) ) Dim Distances#( GWIDTH - 1 ) For i = 0 To Tiles - 1 Texture = LoadImage( "Tile" + ( i + 1 ) + ".png" ) SetBuffer ImageBuffer( Texture ) LockBuffer ImageBuffer( Texture ) For x = 0 To TEXTURESIZE - 1 For y = 0 To TEXTURESIZE - 1 TextureData( i*TEXTURESIZE*TEXTURESIZE + ( x*TEXTURESIZE + y ) ) = ReadPixelFast( x, y ) Next Next FreeImage Texture Next Type Sprite Field X# Field Y# Field Height Field Width Field ImageData[ 256*256 ] End Type Dummy = LoadImage( "Alien.png" ) LockBuffer ImageBuffer( Dummy ) For i = 1 To 10 Drink.Sprite = New Sprite Drink\X# = Rnd( 0, MAPSIZE*GRIDSIZE ) Drink\Y# = Rnd( 0, MAPSIZE*GRIDSIZE ) Drink\Height = ImageHeight( Dummy ) Drink\Width = ImageWidth( Dummy ) For x = 0 To Drink\Width - 1 For y = 0 To Drink\Height - 1 Drink\ImageData[ x*Drink\Width + y ] = ReadPixelFast( x, y, ImageBuffer( Dummy ) ) Next Next If MapData( Drink\X# Shr GRIDSHIFTS, Drink\Y# Shr GRIDSHIFTS ) Then i = i - 1 Next FreeImage( Dummy ) SetBuffer BackBuffer() Restore MapData For i = 0 To MAPSIZE - 1 For t = 0 To MAPSIZE - 1 Read MapData( t, i ) Next Next Timer = CreateTimer( 60 ) DisplayFPS = 0 FPS = 0 Counter = MilliSecs() While Not KeyHit( 1 ) Cls LockBuffer BackBuffer() RenderScreen() RenderSprites() UnlockBuffer BackBuffer() MoveCamera() If MilliSecs() - Counter > 1000 Then DisplayFPS = FPS Counter = MilliSecs() FPS = 0 EndIf Text 0, 0, DisplayFPS Flip 0 WaitTimer Timer FPS = FPS + 1 Wend End Function MoveCamera() XSpeed# = -Sgn( KeyDown( 208 ) - KeyDown( 200 ) )*Cos( CameraAngle ) YSpeed# = Sgn( KeyDown( 208 ) - KeyDown( 200 ) )*Sin( CameraAngle ) TileX = ( CamX# + XSpeed# + Sgn( XSpeed# ) ) Shr GRIDSHIFTS TileY = ( CamY# + YSpeed# + Sgn( YSpeed# ) ) Shr GRIDSHIFTS OldTileX = CamX# Shr GRIDSHIFTS OldTileY = CamY# Shr GRIDSHIFTS If Not MapData( OldTileX, TileY ) Then CamY# = CamY# + YSpeed# If Not MapData( TileX, OldTileY ) Then CamX# = CamX# + XSpeed# CameraAngle = CameraAngle - KeyDown( 203 ) + KeyDown( 205 ) PlaneDisplacement = PlaneDisplacement - KeyDown( 74 ) + KeyDown( 78 ) End Function Function RenderScreen() For i = 0 To GWIDTH - 2 Angle# = ( CameraAngle - ANGLEOFVIEW/2 + CASTINGSTEP#*i ) Mod 360 Angle# = ( 360 + Angle# ) Mod 360 ;Wird der Strahl nach oben oder unten geschickt? YDirection = 1 - ( Angle# < 180 )*2 ;Wird der Strahl nach links oder rechts geschickt? XDirection = -1 + ( Angle# > 270 Or Angle# < 90 )*2 ;Horizontale Kollision Ya# = CamY# Mod GRIDSIZE If YDirection = 1 Then Ya# = GRIDSIZE - Ya# Xa# = Ya#/Tan( Angle# ) IntersectionY# = CamY# + YDirection*Ya# IntersectionX# = CamX# - YDirection*Xa# TileY = ( IntersectionY# + YDirection ) Shr GRIDSHIFTS TileX = IntersectionX# Shr GRIDSHIFTS If TileX >= 0 And TileX < MAPSIZE And TileY >= 0 And TileY < MAPSIZE Then If MapData( TileX, TileY ) Then WallTile = MapData( TileX, TileY ) Else Ya# = YDirection Shl GRIDSHIFTS Xa# = Ya#/Tan( Angle# ) Repeat IntersectionX# = IntersectionX# - Xa# IntersectionY# = IntersectionY# + Ya# TileY = ( IntersectionY# + YDirection ) Shr GRIDSHIFTS TileX = IntersectionX# Shr GRIDSHIFTS If TileX >= 0 And TileX < MAPSIZE And TileY >= 0 And TileY < MAPSIZE Then If MapData( TileX, TileY ) Then WallTile = MapData( TileX, TileY ) Exit EndIf Else Exit EndIf Forever EndIf EndIf WallX# = IntersectionX# WallY# = IntersectionY# ;Vertikale Kollision Xa# = CamX# Mod GRIDSIZE If XDirection = 1 Then Xa# = GRIDSIZE - Xa# Ya# = Xa#*Tan( Angle# ) IntersectionX# = CamX# + XDirection*Xa# IntersectionY# = CamY# - XDirection*Ya# TileY = IntersectionY# Shr GRIDSHIFTS TileX = ( IntersectionX# + XDirection ) Shr GRIDSHIFTS If TileX >= 0 And TileX < MAPSIZE And TileY >= 0 And TileY < MAPSIZE Then If MapData( TileX, TileY ) Then IntersectionTile = MapData( TileX, TileY ) Else Xa# = XDirection Shl GRIDSHIFTS Ya# = Xa#*Tan( Angle# ) Repeat IntersectionX# = IntersectionX# + Xa# IntersectionY# = IntersectionY# - Ya# TileY = IntersectionY# Shr GRIDSHIFTS TileX = ( IntersectionX# + XDirection ) Shr GRIDSHIFTS If TileX >= 0 And TileX < MAPSIZE And TileY >= 0 And TileY < MAPSIZE Then If MapData( TileX, TileY ) Then IntersectionTile = MapData( TileX, TileY ) Exit EndIf Else Exit EndIf Forever EndIf EndIf DistanceVertically# = Abs( ( WallY# - CamY# )/Sin( Angle# ) ) DistanceHorizontally# = Abs( ( IntersectionX# - CamX# )/Cos( Angle# ) ) If DistanceHorizontally# < DistanceVertically# Then SmallerDistance# = DistanceHorizontally# If WallTile > 0 Then If HD Then TextureRow = Floor( ( WallX# Mod GRIDSIZE )*SCALEFACTOR# ) Else TextureRow = Floor( WallX# ) Mod GRIDSIZE EndIf EndIf If HD Then TextureRow = Floor( ( IntersectionY# Mod GRIDSIZE )*SCALEFACTOR# ) Else TextureRow = Floor( IntersectionY# ) Mod GRIDSIZE EndIf Else SmallerDistance# = DistanceVertically# If IntersectionTile > 0 Then If HD Then TextureRow = Floor( ( IntersectionY# Mod GRIDSIZE )*SCALEFACTOR# ) Else TextureRow = Floor( IntersectionY# ) Mod GRIDSIZE EndIf EndIf If HD Then TextureRow = Floor( ( WallX# Mod GRIDSIZE )*SCALEFACTOR# ) Else TextureRow = Floor( WallX# ) Mod GRIDSIZE EndIf EndIf WallHeight = ( GRIDSIZE/( SmallerDistance#*Cos( CASTINGSTEP#*i - ANGLEOFVIEW/2 ) ) )*ProjectionDistance# If WallTile = 0 And IntersectionTile > 0 Then WallTile = IntersectionTile TStart = ( GHEIGHT/2 + PlaneDisplacement ) - WallHeight/2 TEnd = ( GHEIGHT/2 + PlaneDisplacement ) + WallHeight/2 If TStart < 0 Then YCorrection = Abs( TStart ) If TEnd >= GHEIGHT Then YCorrection2 = TEnd - GHEIGHT + 1 For t = TStart + YCorrection To TEnd - YCorrection2 If WallTile = 1 Then WritePixelFast i, t, $FFFFFFFF Else ARGB = TextureData( ( WallTile - 2 )*TEXTURESIZE*TEXTURESIZE + ( TextureRow*TEXTURESIZE + ( t - GHEIGHT/2 + WallHeight/2 - PlaneDisplacement )*( TEXTURESIZE/Float( WallHeight ) ) ) ) WritePixelFast i, t, ARGB EndIf Next ;Floor - Casting TStart = ( GHEIGHT/2 + PlaneDisplacement ) + WallHeight/2 TStart = TStart*( TStart >= 0 ) TEnd = GHEIGHT ;******************************** For t = TStart To TEnd-1 ;fixed ;******************************** Length# = ( ( GRIDSIZE/2 )/( ( t - GHEIGHT/2 - PlaneDisplacement )/ProjectionDistance# ) )/Cos( CASTINGSTEP#*i - ANGLEOFVIEW/2 ) FloorX = CamX# + Cos( Angle# )*Length# FloorY = CamY# - Sin( Angle# )*Length# TextureColumn = FloorY Mod TEXTURESIZE TextureRow = FloorX Mod TEXTURESIZE ARGB = TextureData( ( FLOORTILE - 1 )*TEXTURESIZE*TEXTURESIZE + ( TextureRow*TEXTURESIZE + TextureColumn ) ) If i >= 320 Or t >= 200 Then Print i+" "+t+" third" WritePixelFast i, t, ARGB Next If CEILING Then ;Ceil - Casting TStart = 0 TEnd = ( GHEIGHT/2 + PlaneDisplacement ) - WallHeight/2 TEnd = TEnd*( TEnd < GHEIGHT ) + ( GHEIGHT - 1 )*( TEnd >= GHEIGHT ) ;************************************* For t = TStart To TEnd-1 ;fixed ;************************************* Length# = ( ( GRIDSIZE/2 )/( ( GHEIGHT/2 - t + PlaneDisplacement )/ProjectionDistance# ) )/Cos( CASTINGSTEP#*i - ANGLEOFVIEW/2 ) CeilingX = CamX# + Cos( Angle# )*Length# CeilingY = CamY# - Sin( Angle# )*Length# TextureRow = CeilingX Mod TEXTURESIZE TextureColumn = CeilingY Mod TEXTURESIZE ARGB = TextureData( ( CEILINGTILE - 1 )*TEXTURESIZE*TEXTURESIZE + ( TextureRow*TEXTURESIZE + TextureColumn ) ) WritePixelFast i, t, ARGB Next EndIf Distances#( i ) = SmallerDistance# TextureRow = 0 IntersectionTile = 0 WallTile = 0 Saviour = 0 YCorrection = 0 YCorrection2 = 0 Next End Function Function RenderSprites() ;Sprites For Drink.Sprite = Each Sprite Distance# = Sqr( ( CamX# - Drink\X# )*( CamX# - Drink\X# ) + ( CamY# - Drink\Y# )*( CamY# - Drink\Y# ) ) Height = Drink\Height - 1 Width = Drink\Width SpriteHeight = ( Height/Distance# )*ProjectionDistance# SpriteWidth = Width*( SpriteHeight/Float( Height ) ) Difference# = ATan( ( Drink\Y# - CamY# )/( Drink\X# - CamX# ) ) If Drink\X# - CamX# < 0 Then Difference# = 180 + Difference# Angle# = ( -Difference# - CameraAngle + 360 ) Mod 360 StartSlice = ( Angle# + ANGLEOFVIEW/2 )/CASTINGSTEP# - SpriteWidth/2 If ( StartSlice < 0 Or StartSlice > GWIDTH ) And Abs( Angle# ) > 360 - ANGLEOFVIEW/2 - SpriteWidth/2 Then Angle# = Angle# - Sgn( Angle# )*360 StartSlice = ( Angle# + ANGLEOFVIEW/2 )/CASTINGSTEP# - SpriteWidth/2 EndIf XStart = StartSlice*( StartSlice >= 0 ) XEnd = StartSlice + SpriteWidth - 1 XEnd = XEnd*( XEnd < GWIDTH ) + ( GWIDTH - 1 )*( XEnd > GWIDTH ) YStart = ( GHEIGHT/2 - Spriteheight/2 + PlaneDisplacement )*( GHEIGHT/2 - SpriteHeight/2 + PlaneDisplacement >= 0 ) YEnd = GHEIGHT/2 + SpriteHeight/2 - 1 + PlaneDisplacement YEnd = YEnd*( YEnd <= GHEIGHT ) + GHEIGHT*( YEnd > GHEIGHT ) ;************************************** For x = XStart To XEnd-1 ;fixed maybe? For y = YStart To YEnd-1 ;fixed maybe? ;***************************************** If Distances#( x ) > Distance# Then ARGB = Drink\ImageData[ Floor( ( x - StartSlice )*( Width/Float( SpriteWidth ) ) )*Drink\Width + ( y - GHEIGHT/2 + SpriteHeight/2 - PlaneDisplacement )*( Height/Float( SpriteHeight ) ) ] If ARGB - $FF000000 <> 0 Then If x >= 320 Or y >= 200 Then Print x+" "+y+" fifth" WritePixelFast x, y, ARGB EndIf EndIf Next Next Next End Function .MapData Data 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2 Data 2, 0, 0, 0, 2, 0, 0, 0, 2, 0, 0, 0, 0, 0, 0, 2 Data 1, 0, 2, 0, 2, 0, 2, 0, 2, 2, 2, 2, 2, 2, 0, 2 Data 2, 2, 2, 0, 0, 0, 2, 0, 0, 2, 0, 0, 0, 0, 0, 2 Data 2, 2, 2, 2, 2, 2, 2, 2, 0, 2, 2, 2, 0, 2, 2, 2 Data 2, 2, 2, 0, 0, 0, 0, 2, 0, 0, 0, 2, 0, 2, 0, 2 Data 2, 2, 2, 0, 0, 0, 0, 2, 2, 2, 0, 0, 0, 2, 0, 2 Data 2, 2, 2, 0, 2, 2, 0, 2, 2, 2, 2, 2, 0, 2, 0, 2 Data 2, 2, 2, 0, 2, 2, 0, 2, 0, 0, 0, 2, 0, 2, 0, 2 Data 2, 2, 2, 0, 0, 0, 0, 2, 0, 2, 0, 2, 0, 0, 0, 2 Data 2, 0, 2, 0, 0, 0, 0, 2, 0, 2, 0, 2, 2, 2, 0, 2 Data 2, 0, 2, 0, 0, 0, 0, 2, 0, 2, 0, 2, 0, 0, 0, 2 Data 2, 0, 2, 0, 0, 0, 0, 2, 0, 2, 0, 0, 0, 2, 0, 2 Data 2, 0, 2, 2, 2, 2, 0, 2, 2, 2, 2, 2, 2, 2, 0, 2 Data 2, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 2 Data 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2

Noobody (Posted 2008) [#5]

Thanks, Jesse, I really have to be dumb to do such simple mistakes :D What I forgot to mention, if you take out the WaitTimer, it will be much faster (that's not an april fool ;) ). On my crappy Intel Celeron FPS are between 100 and 200, which is imho acceptable.

Panno (Posted 2008) [#6]

not bad ;)