mirror problem

Blitz3D Forums/Blitz3D Programming/mirror problem

mouss38

(Posted 2003) [#1]

everything above and below a mirror seems to be reflected. but when you need to attach a mirror to a infinite water plane, all objects below the mirror don't have to be reflected.
Is it possible to use a mirror in order to reflect ony objects above it ?

Akat	(Posted 2003) [#2]

try using CreateMirror() function code - which u can get it from BlitzSupport... but some bug noticeable when the camera too close with the mirror plane - or u have to wait for B3D update which is come with cube mapping reflections...

mouss38

(Posted 2003) [#3]

i can't find it... where is it?

Akat	(Posted 2003) [#4]

try find it under my thread about creating a mirror - i dont even remember where it is - or u can ask BlitzSupport for code call 'RealMirror'.

note: i think it not suitable for Water Reflection, like it name, maybe only for mirror reflection - but worth try

LostCargo

(Posted 2003) [#5]

when is the b3d update comming through? anyone know?

Akat	(Posted 2003) [#6]

nope... nobody know even mark himself

yinch

(Posted 2003) [#7]

You could two Render Passes on the scene.
1st Pass
Hide water surface, mirror + all objects above water level
Render all objects below water

2nd Pass
Hide all objects below water
Render all other objects

So roughly,

; not really code, just procedure
; Underwater Objects
HideEntity WaterAndObjectsAbove
ShowEntity ObjectsBelow
UpdateWorld()
RenderWorld()

; Overwater and Water Surface
ShowEntity WaterAndObjectsAbove
HideEntity ObjectsBelow
UpdateWorld()
RenderWorld()
Flip()

NOTE -
1. the mirror plane is grouped with the ObjectsAbove the water plane
2.for objects which actually intersect the mirror-plane, you should group them with the ObjectsBelow (so they dont reflect)

Ross C

(Posted 2003) [#8]

here's some code i made up. should do the trick. when your rendering a mirror tho, try and hide all the things you know or you can check that won't be in view :D

Graphics3D 800,600,16

cube=CreateCube()
PositionEntity cube,-3,0,2

plane=CreatePlane()
EntityColor plane,40,40,200
MoveEntity plane,0,-2,0

planetex=CreateTexture(256,256)
SetBuffer TextureBuffer(planetex)
For loop=0 To 255 Step 2
	For loop1=0 To 255 Step 2
		Color 50,50,200
		Rect loop,loop1,1,1
		Color 20,20,200
		Rect loop+1,loop,1,1
		Color 50,50,200
		Rect loop,loop1+1,1,1
		Color 20,20,200
		Rect loop+1,loop1+1,1,1
	Next
Next

SetBuffer BackBuffer()

ScaleTexture planetex,200,200
EntityTexture plane,planetex

sphere=CreateSphere()


camera=CreateCamera(sphere)
PositionEntity camera,0,3,-5
CameraRange camera,1,100

mirror=CreateCube()
PositionEntity mirror,0,3,10
ScaleEntity mirror,3,1.5,0.2

mirrorframe=CreateCube()
PositionEntity mirrorframe,0,3,10.2
ScaleEntity mirrorframe,3.3,1.7,0.3
RotateEntity mirrorframe,20,180,0
EntityColor mirrorframe,70,70,200

mirrorcam=CreateCamera(mirror)
PositionEntity mirrorcam,0,0,0
HideEntity mirrorcam
CameraRange mirrorcam,1,100

mirrortex=CreateTexture(256,256,256)
EntityTexture mirror,mirrortex
ScaleTexture mirrortex,-1,1

light=CreateLight()

RotateEntity mirror,20,180,0

Color 255,255,255

While Not KeyHit(1)
	
	
	If KeyDown(200) Then MoveEntity sphere,0,0,0.1
	If KeyDown(208) Then MoveEntity sphere,0,0,-0.1
	If KeyDown(203) Then TurnEntity sphere,0,1,0
	If KeyDown(205) Then TurnEntity sphere,0,-1,0

	If MilliSecs()<timer+1000 Then
								frame=frame+1
	Else
								fps=frame
								frame=0
								timer=MilliSecs()
	End If
	Gosub updatemirror
	UpdateWorld
	RenderWorld
	Text 0,0,"fps="+fps
	Flip
Wend
End

.updatemirror
	HideEntity camera
	ShowEntity mirrorcam
	RenderWorld
	CopyRect 272,172,255,255,0,0,BackBuffer,TextureBuffer(mirrortex)
	HideEntity mirrorcam
	ShowEntity camera
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