Platform Collision Test Code

Hi All,

I've been playing with the Blitz collision system to see how it works and have come up with the little snippet you see below. My question is, does the collision and sliding in this feel correct for a platform style game?

I haven't added any time dependent code so it will run at different speeds on different machines. I'm not really concerned with the camera following, just the collision of the cylinder against the rest of the world. I'm just curious what others think. Thanks for your comments.

left alt key = jump
arrow keys = move

Ken

; platformer collision test
; Kenneth "Physt" Lemieux
; kenlem@...
; No Rights Reserved

;left alt key = jump 
;arrow keys = move 

Global gravity# = -0.02
Global speed# = 0.09

Global x# = 10 
Global y# = 50
Global z# = 10

Global platvel# = .025

Graphics3D 640, 480

GameLoop()

Function GameLoop()

	
	
	frametimer = CreateTimer(60)

	light=CreateLight()
	RotateEntity light,45,45,0

	camera=CreateCamera()
	PositionEntity camera, 10, 10, 10

	player = CreateCylinder(32)
	FitMesh player, -1, -1, -1, 2, 2, 2, False
	
	level = CreateCube()
	
	grid=CreateTexture(64,64,9)
	SetBuffer TextureBuffer(grid)	
	Color 32,64,128
	Rect 0, 0, 64,64, 1
	Color 255,255,255
	Rect 0, 0, 64,64, 0
	
	SetBuffer BackBuffer()


	ScaleTexture grid, .1, .1
	EntityTexture level, grid
	FitMesh level, -40, -40, -40, 80, 80, 80, True 
	FlipMesh(level)
	
	platform1 = CreateCube()
	FitMesh platform1, -10, -25, -10, 10, 1, 10, False
	EntityTexture platform1, grid

	
	
	platform2 = CreateCube()
	FitMesh platform2 , -10, -30,  10, 10, 1, 10, False
	EntityTexture platform2 , grid

	
	platform3 = CreateCube()
	FitMesh platform3 , -15, -35,  10, 10, 1, 10, False
	EntityTexture platform3 , grid
	
	platform4 = CreateCube()
	FitMesh platform4 , -16, -20,  7, 10, 1, 10, False
	EntityTexture platform4 , grid

	

	EntityType player,1
	EntityType level, 2
	EntityType platform1, 2
	EntityType platform2, 2
	EntityType platform3, 2
	EntityType platform4, 2

	Collisions 1, 2, 2, 2

	While Not KeyDown(1)
	
		; left
		If KeyDown(203) Then	
			TurnEntity player, 0, 3, 0
		End If 
	
		; right
		If KeyDown(205) Then
			TurnEntity player, 0, -3, 0 
		End If 
		
		; down
		If KeyDown(208) Then 
			TFormVector 0, 0, 1, player, 0
			xvel# = xvel# - (TFormedX() * speed#)
			yvel# = yvel# - (TFormedY() * speed#)
			zvel# = zvel# - (TFormedZ() * speed#)
		End If 
		
		; up arrow forward
		If KeyDown(200) Then 
			TFormVector 0, 0, 1, player, 0
			xvel# = xvel# + (TFormedX() * speed#)
			yvel# = yvel# + (TFormedY() * speed#)
			zvel# = zvel# + (TFormedZ() * speed#)
		End If 
		
		collide = CountCollisions (player)
		If collide > 0 Then 
			For i = 1 To collide
				NY# = CollisionNY(player,  i)
				If NY# > 0  Then	
					yvel# = yvel# - gravity#
					If KeyDown(29) Then
						yvel# = yvel# + .60
						If yvel# < .4 Then
							yvel# = 0
						End If
					End If  	
				Else If NY#=-1 Then 
					;yvel# = -yvel# * .5
					yvel# = 0
				End If
			Next  
		End If 
 		
		
		yvel# = yvel# + gravity#	
		x# = x# + xvel#
		y# = y# + yvel# 
		z# = z# + zvel#
		xvel# = xvel# * .7
		zvel# = zvel# * .7
		PositionEntity player, x#, y#, z#
		
		UpdateWorld()

			
		PositionEntity camera, EntityX(player), EntityY(player)+2, EntityZ(player)
		RotateEntity camera ,EntityPitch(player), EntityYaw(player)+4, EntityRoll(player)
		MoveEntity camera, 0, 0, -5
		PointEntity camera, player
		
		x# = EntityX(player)
		y# = EntityY(player)
		z# = EntityZ(player)
		
		RenderWorld()
		Flip
	Wend

End Function