Light-problems in orthogonal view (...and more...)

Blitz3D Forums/Blitz3D Beginners Area/Light-problems in orthogonal view (...and more...)

Abomination

(Posted 2008) [#1]

I've bodged several bits of example-code together, to try to get a orthogonal view of a triangle-tiled mesh.
This picture is the result so far:

Now I would expect just the "cone" to be lit from the one side and shaded on the other.
But the adjacent triangles (witch are flat, also show light and shadow.
Is there a way to have just the cone (hill) to be lit and not the surroundings? Or is this result to be expected?
A second question I have is; how much do I have to scale the mesh,
to get a "more or less" pixel-perfect representation of the brush?

Const UI_distance=-10000	; Camera distance for UI camera

Global TG_camera.TG_cam

Type TG_cam
	Field camera%		; Pointer to camera entity
	Field pos_x%
	Field pos_y%
	Field siz_x%
	Field siz_y%
End Type

TG_camera.TG_cam = New TG_cam

; UI constructors
Function TG_Initialise()
	; FUNCTION :  initialise UI camera and mouse pointer
	; loads rectangular mesh that's basis of all UI sprites
	HidePointer()
	
	TG_sprite = CreateMesh() 
	surf = CreateSurface(TG_sprite) 
	
	
	TG_camera\camera=CreateCamera()
	PositionEntity TG_camera\camera,0,0,UI_distance
	CameraProjMode(TG_camera\camera,0)				; 0 to hide, 2 to render
	CameraClsMode(TG_camera\camera,0,1)
	CameraRange TG_camera\camera,1,100

End Function

; UI control
Function TG_Draw_UI()
	UpdateWorld
	RenderWorld
	CameraProjMode (TG_camera\camera,2)
End Function

;Map values 
Const MINMapSize=5
Const MaxSlope=4
Const MinHeight=0
Const MaxHeight=31


;Triangle values
;Const TriD=20,TriDMin =TriD-1 ;d=depth
Const TriWidth=20,TriWidthMin=TriWidth-1
Const TriHeight=20,TriHeightMin=TriHeight-1
Const triviewwidth=11
Const triviewheight=11


Const upuv  =0
Const downuv =1
Const leftuv =2
Const rightuv=3
Const miduv  =4

;Map Variables
Global HeightMap,RSUSurfMap,USDSurfMap
Global MapMaxSize=6
Global MapXPos=0,MapYPos=0
Global MapPos;position in bank
Global MapMinPos,MapMaxPos

Global TSP;totalscreenpoints
Global MapSize=5;number of landsize
Global MapWidth;width (and Depth) of land
Global MapAnd;mapwidth-1
Global BnkSize;total bytes of positions in a map
Global BankAnd;BnkSize-1
Global MapR,MapL
Global MapLU
Global MapRU
Global MapLD
Global MapRD

;Triangle values
Global SurfaceMesh
Global SurfaceBrush
Global SurfaceSurface

Dim vertexMap(triwidthmin,triheightmin,5);array with RUS and USD TRI

Dim SurfaceDat#(15,4)

SurfaceDat(0,upuv)  = 0.01
SurfaceDat(0,downuv) = 0.24
SurfaceDat(0,leftuv) = 0.01
SurfaceDat(0,rightuv) = 0.24
SurfaceDat(0,miduv)  = 0.125

SurfaceDat(1,upuv)  = 0.01
SurfaceDat(1,downuv) = 0.24
SurfaceDat(1,leftuv) = 0.26
SurfaceDat(1,rightuv) = 0.49
SurfaceDat(1,miduv)  = 0.375

SurfaceDat(2,upuv)  = 0.01
SurfaceDat(2,downuv) = 0.24
SurfaceDat(2,leftuv) = 0.51
SurfaceDat(2,rightuv) = 0.74
SurfaceDat(2,miduv)  = 0.625

SurfaceDat(3,upuv)  = 0.01
SurfaceDat(3,downuv) = 0.24
SurfaceDat(3,leftuv) = 0.76
SurfaceDat(3,rightuv) = 0.99
SurfaceDat(3,miduv)  = 0.875


;
Graphics3D 800,600,0,0


TG_Initialise()

Init_Surface()
Generate_Map()

Create_Surface_Mesh()

	Orthogonal_light=CreateLight (2,SurfaceMesh);(1,TG_camera\camera)
	LightColor Orthogonal_light,255,255,255
	PositionEntity Orthogonal_light,-1000,100,-1000
	PointEntity Orthogonal_light,SurfaceMesh

While Not KeyHit(1)
	TG_Draw_UI()
	Flip False
Wend
End


Function Init_Surface()
	; Doctored sprite code from Skidracer
	; 'texture' is a pointer to a texture object, in sizes of squared powers of 2. eg. 128x128 or 256x256
	; this is because GPU's work fastest with power of 2 textures
	; optional x_size and y_size values crop the sprite to fit
	; eg. for a 27x18 button, create a 32x32 source image, load as texture, and call TG_Load_Sprite(texture,27,18)
	; No x_size or y_size values uses texture proportions
	
	; change these for viewports
	viewwidth=GraphicsWidth()
	viewheight=GraphicsHeight()
	; find existing pixiespace parented to camera
	magic=0
	n=CountChildren(TG_camera\camera)
	For i=1 To n
		If EntityName(GetChild(TG_camera\camera,i))="pixiespace" 
			magic=GetChild(GetChild(TG_camera\camera,i),1)
		EndIf
	Next
	If magic=0
		magic=CreatePivot(TG_camera\camera)
		NameEntity(magic,"pixiespace")
		aspect#=Float(viewheight)/viewwidth
		PositionEntity magic,-1,aspect,1 
		scale#=2.0/viewwidth 
		ScaleEntity magic,scale,-scale,-scale 
		magic=CreatePivot(magic)
		PositionEntity magic,-.5,-.5,0
	EndIf
;gfxstuff
	SurfaceMesh = CreateMesh (Magic)
	scale#=0.2/viewwidth 
	SurfaceBrush = LoadBrush ("gfx\MapTextures\surface.png")
	SurfaceSurface = CreateSurface (SurfaceMesh)
	PaintSurface SurfaceSurface, SurfaceBrush
;arraystuff
;fill the mesh with nonsence
	sh#=0
	shz=0
	For z = 0 To TriHeightMin
		For x= 0 To TriWidthMin
			posz=TriHeight- (z+1)
			posx#=x+sh
			rsuLeft  = AddVertex (SurfaceSurface, posx - 0.5,0, posz - 1     ,1,0  )
			rsuMid  = AddVertex (SurfaceSurface, posx      ,0, posz    ,0,0.5)
			rsuRight = AddVertex (SurfaceSurface, posx + 0.5,0, posz - 1     ,1,0  )
			AddTriangle (SurfaceSurface, rsumid,rsuright,rsuleft)
			VertexMap(x,z,0)=rsumid
			VertexMap(x,z,1)=rsuright
			VertexMap(x,z,2)=rsuleft

			usdleft  = AddVertex (SurfaceSurface, posx      ,0, posz         ,0,1  )
			usdMid  = AddVertex (SurfaceSurface, posx + 0.5,0, posz - 1     ,1,0.5)
			usdright = AddVertex (SurfaceSurface, posx + 1.0,0, posz         ,0,1  )
			AddTriangle (SurfaceSurface, usdleft,usdright,usdmid)
			VertexMap(x,z,3)=usdleft
			VertexMap(x,z,4)=usdRight
			VertexMap(x,z,5)=usdmid
		Next
		sh = 0.5 - sh:If sh=0 Then shz=shz+1
	Next
	ScaleEntity SurfaceMesh, 100, 100, 100
	PositionEntity SurfaceMesh, 00, 400, UI_distance-200
	RotateEntity SurfaceMesh,150,0,0
 End Function

Function Create_Surface_Mesh()
	sh#=0
	shz=0
	For z = 0 To TriHeightMin
		For x= 0 To TriWidthMin
			MP=(MapPos+MapWidth*z+x+2*sh+shz) And BankAnd
			rsuSurf =PeekByte(rsusurfMap,(MP)) And 3
			usdSurf =PeekByte(usdsurfMap,(MP)) And 3
			posz=TriHeight- (z+1)
			posx#=x+sh
	
			VertexCoords SurfaceSurface,vertexmap(x,z,2), posx - 0.5,0.1* PeekByte(heightmap,MP+MapLD), posz - 1
			VertexCoords SurfaceSurface,vertexmap(x,z,0), posx      ,0.1* PeekByte(heightmap,MP)      , posz
			VertexCoords SurfaceSurface,vertexmap(x,z,1), posx + 0.5,0.1* PeekByte(heightmap,MP+MapRD), posz - 1
			VertexCoords SurfaceSurface,vertexmap(x,z,3), posx      ,0.1* PeekByte(heightmap,MP)      , posz
			VertexCoords SurfaceSurface,vertexmap(x,z,5), posx + 0.5,0.1* PeekByte(heightmap,MP+MapRD), posz - 1
			VertexCoords SurfaceSurface,vertexmap(x,z,4), posx + 1.0,0.1* PeekByte(heightmap,MP+MapR) , posz


			VertexTexCoords SurfaceSurface,vertexmap(x,z,2), SurfaceDat(rsuSurf,leftuv) , SurfaceDat(rsuSurf,downuv)
			VertexTexCoords SurfaceSurface,vertexmap(x,z,0), SurfaceDat(rsuSurf,miduv)  , SurfaceDat(rsuSurf,upuv)
			VertexTexCoords SurfaceSurface,vertexmap(x,z,1), SurfaceDat(rsuSurf,rightuv), SurfaceDat(rsuSurf,downuv)
			VertexTexCoords SurfaceSurface,vertexmap(x,z,3), SurfaceDat(usdSurf,leftuv) , SurfaceDat(usdSurf,upuv)
			VertexTexCoords SurfaceSurface,vertexmap(x,z,5), SurfaceDat(usdSurf,miduv)  , SurfaceDat(usdSurf,downuv)
			VertexTexCoords SurfaceSurface,vertexmap(x,z,4), SurfaceDat(usdSurf,rightuv), SurfaceDat(usdSurf,upuv)
		Next
		sh = 0.5 - sh:If sh=0 Then shz=shz+1
	Next
 UpdateNormals SurfaceMesh
End Function



Function Generate_Map()
MapSize=5
MapWidth=2^MapSize;width (and Depth) of land
MapAnd=MapWidth-1;mapwidth-1
BnkSize=(MapWidth*MapWidth);total bytes of positions in a map
BankAnd=BnkSize-1;BnkSize-1
MapMinPos=MapWidth+1
MapMaxPos=BnkSize-(MapWidth+1)
MapR=1
MapL=-1
MapLU=-MapWidth-1
MapRU=-MapWidth
MapLD=MapWidth
MapRD=MapWidth+1
MapPos=MapMinPos

	HeightMap=CreateBank(BnkSize)
	z=0
	Repeat
		For x=0 To MapAnd
			PokeByte HeightMap,z+x,0;Rand(0,19)
		Next
		z=z+MapWidth
	Until z=BnkSize
	
			PokeByte HeightMap,12+16*MapWidth,18;Rand(0,19)
			PokeByte HeightMap,15+18*MapWidth,1;Rand(0,19)

	rsusurfMap=CreateBank(BnkSize)
	z=0
	Repeat
		For x=0 To MapAnd
			PokeByte rsusurfMap,z+x,Rand(1,1)
		Next
		z=z+MapWidth
	Until z=BnkSize

	usdsurfMap=CreateBank(BnkSize)
	z=0
	Repeat
		For x=0 To MapAnd
			PokeByte usdsurfMap,z+x,Rand(1,1)
		Next
		z=z+MapWidth
	Until z=BnkSize

End Function

Any help or pointers I would greatly appreciate.

This is the brush I used:

Abomination

(Posted 2008) [#2]

.bump
Well... it seems that I can stop the surrounding triangles from participating
with the ascended ones, by shifting the position of the vertexes?! a weeny bit.
It creates a kind of flat shaded effect.

nice.
But not what I wanted.
I suppose, dividing the triangles a few times would lessen the "reflect-to-the-ground-effect"
hmm

Pete Carter

(Posted 2008) [#3]

i beleave b3d is smoothing your mesh you can stop this by using smoothing groups in your modeler, or you can unweld the cone fro the rest of the mesh and the it will give you a hard edge but the cone will still stay smooth.

i think this is what you are getting at?

its the same in most modellers, but i dont think you can set a meshes smoothing angle in blitz3d, i maybe wrong?

heres a quick example

image and the right normal smoothing, image on the left with cone unwelded.

Abomination

(Posted 2008) [#4]

I suppose I did that unwelding thing in my last example (trimm.jpg), except that my code unwelded every triangle; but if I kept the cone-vertexes the way they were the result would probably be simular to your examples.
Prob is that I dont use a modeler but some code to transfer a heightmap to a mesh.
My example was to illustrate the (in my eyes) strange effect.
p.s.
emm... How do you get your example-pic to show in the browser?
I've been fiddling with them forum codes for half an hour, but no sigar.

Pete Carter

(Posted 2008) [#5]

you dont have to use forum codes just put the full url to your pic and it will display it.

I have no idea how to sort it out in code im sorry.

Pete

Gabriel

(Posted 2008) [#6]

URL's have to be URL encoded in order to display properly. That ~ character should not be in a URL encoded link.

I think it should be ( without the spaces )
http://www.xs4all.nl/ %7e dshorror/trimm.JPG

Abomination

(Posted 2008) [#7]

HA!
And again it's them little things!
Cheers Gabriel