irrlicht - questions

[Philippe-felixer76-2]

Hi there great makers and testers of the PB irrlicht wrapper,

First off, great work, cool to play arround with irrlicht.

i was wondering, how can i delete a texture, because all commands
contain irradd, but no irrdelete or irrremove, so it's memory consuming
when you for instance add realtime generated self made textures.

Second, the terrain functions contain a function: IrrTerrainHeight,
this functions obtains the height of the x/z position, thats very
handy but how is it possible to change this height, i would expect
to have a IrrGetTerrainHeight and IrrSetTerrainHeight function.

And how to obtain the terrain width/height?

And the documentation overal should contain example images,
specialy for the GUI part.

But very nice work! Love it!

Gr,
Phil.

[neotoma]

Hi Phil,

sorry for the late response.

You are right, there is no command to remove a texture. But all pointers in Irrlicht contains a 'counter', to know if the Object (behind the pointer)
stil in use. So C++ ha not GarbageCollector and we have to remove the objects/pointers self. In the IrrlichtWrappe4r is a Command IrrDropPointer(). That decreases the 'counter' and removes the object if the counter is 0.
You can use this to 'remove' textures. But keep in mind - if the Texture(-Object) still used from another Object, it will not be removed !

Second, the terrain functions contain a function: IrrTerrainHeight,
this functions obtains the height of the x/z position, thats very
handy but how is it possible to change this height, i would expect
to have a IrrGetTerrainHeight and IrrSetTerrainHeight function.

The Terrain-SceneNode in Irrlicht has a nice feature - called 'Level of Detail (LOD)'. And that is the problem with changing the height a point in the terrain. Irrlicht 'precalculates' the Meshes for the all LOD of the Terrain on init. So there a re onle 2 ways around thet -

* Don't use LOD

* recalculate the Terrain (with a new Node and removing the old one... )

Both are not really nice, but you can also use your own Mesh (IrrCreateMesh() ) and then change the vertices by yourself.

Long time ago (Irrlicht 0.11) i made a min-terrain-editor without LOD.
It works. So if that what you want, i can (if i got the time), add some functions to make this also possible from PB. (Please send a PM)

(In the Irrlicht-Snippets-Forum was a addition : http://irrlicht.sourceforge.net/phpBB2/ ... ht=terrain
But with the same anwers as i explained above.

And how to obtain the terrain width/height?

The Terrain Width/Height based on the size of the Texture and the scaling.


Hope this helps....

Mike

[Philippe-felixer76-2]

Hi Phil,

sorry for the late response.

You are right, there is no command to remove a texture. But all pointers in Irrlicht contains a 'counter', to know if the Object (behind the pointer)
stil in use. So C++ ha not GarbageCollector and we have to remove the objects/pointers self. In the IrrlichtWrappe4r is a Command IrrDropPointer(). That decreases the 'counter' and removes the object if the counter is 0.
You can use this to 'remove' textures. But keep in mind - if the Texture(-Object) still used from another Object, it will not be removed !

Second, the terrain functions contain a function: IrrTerrainHeight,
this functions obtains the height of the x/z position, thats very
handy but how is it possible to change this height, i would expect
to have a IrrGetTerrainHeight and IrrSetTerrainHeight function.

The Terrain-SceneNode in Irrlicht has a nice feature - called 'Level of Detail (LOD)'. And that is the problem with changing the height a point in the terrain. Irrlicht 'precalculates' the Meshes for the all LOD of the Terrain on init. So there a re onle 2 ways around thet -

* Don't use LOD

* recalculate the Terrain (with a new Node and removing the old one... )

Both are not really nice, but you can also use your own Mesh (IrrCreateMesh() ) and then change the vertices by yourself.

Long time ago (Irrlicht 0.11) i made a min-terrain-editor without LOD.
It works. So if that what you want, i can (if i got the time), add some functions to make this also possible from PB. (Please send a PM)

(In the Irrlicht-Snippets-Forum was a addition : http://irrlicht.sourceforge.net/phpBB2/ ... ht=terrain
But with the same anwers as i explained above.

And how to obtain the terrain width/height?

The Terrain Width/Height based on the size of the Texture and the scaling.


Hope this helps....

Mike

Tnx for the reply..

Can i pass a texture pointer to IrrDropPointer() ?!

About the terrain height, the C code is to difficult for
me to create a PB lib out of that. You might wanne
help?!

Or the mesh way might be the solution.

Offcourse i like the terrain editor ...

Gr,
Phil.

[Thalius]

Hi Phil

About Terrain:
The Terraindimension is the Dimension of your heightmapimagefile^2 multiplied by your nodescale as mike said.

Alternatively where Get and Set height Functions are available one can use The TlT ( TiledTerrain) functions ( which i am playing around currently to docu for the stable ... ).



Heres the modified Terrain Example to demonstrate this.

Code: Select all

;; ----------------------------------------------------------------------------
;; Irrlicht Wrapper For Imperative Languages - Purebasic Examples
;; IrrlichtWrapper and FreeBasic-Example by Frank Dodd (2006)
;; Improved IrrlichtWrapper - Michael Taupitz (2007)
;; PureBasic-Examples by Michael Taupitz (neotoma) & Marius Eckardt (Thalius) 
;; Last Edit: 25.10.2007
;; ----------------------------------------------------------------------------
;; Example 10 : Terrain And Fog
;; This example creates a terrain from a bitmap heightfield And displays it in
;; a foggy scene
;; ----------------------------------------------------------------------------
;;

;; ////////////////////////////////////////////////////////////////////////////
;; Include the Irr3D-Requester
XIncludeFile "Irr3DRequester.pb"

;; ////////////////////////////////////////////////////////////////////////////
;; Global variables

; irrlicht objects
*terrain.irr_terrain
*TerrainNode.irr_node
*TerrainTexture0.irr_texture
*TerrainTexture1.irr_texture
*camera.irr_camera
*CameraNode.irr_node

; Defines
Define x.f, y.f, z.f, Height.f

; Little helper function to get an ImageDimension...
; // Result = ImageDimension( FileName$ [, Axis])
; // Axis can be 0 -> X (Width) or 1 -> Y (Height) : Default Width is returned. 
; // Returns X or Y Dimensions of given Imagefile or 0 if fail ( kinda bulletproof ... ) =p
Procedure ImageDimension(file.s,axis.l = 0)
  
  Result.l = 0
  
  If LoadImage(0, file.s)
    
    If IsImage(0)
      Select axis.l
        Case 1 ; Y
          Result.l = ImageHeight(0)
        Default ; X
          Result.l = ImageWidth(0)
      EndSelect
      FreeImage(0)
    EndIf 
  
  EndIf

  ProcedureReturn Result.l
EndProcedure

; -----------------------------------------------------------------------------
; To Start the Irrlicht-Device we use the Irr3DRequester, to make it more comfortable
; for the Users, and also easier to test different resolutions and devices.
If Irr3DRequester()

  ; send the window caption
  IrrSetWindowCaption( "Example 10: Terrain and Fog" )
  
  ; here we create the terrain from a greyscale bitmap where bright pixels are
  ; high points and black pixels are low points. the command generates the mesh
  ; and automatically adds it as a node to the scene
  *terrain = IrrAddTerrain( "media\terrain-heightmap.bmp" )
  ; We Read out the ImageWidth which is our Terrain Dimension
  TerrainWidth.l = ImageDimension( "media\terrain-heightmap.bmp" )
  
  ; the node is too small to be a proper terrain so we get the node object of the
  ; terrain and scale its size up 40 times along the X and Z axis and just 4 times
  ; along the Y axis
  *TerrainNode = *terrain
  TerrainScaleXZ.f = 40.0 
  TerrainScaleY.f  = 4.0
  IrrSetNodeScale( *TerrainNode, TerrainScaleXZ.f, TerrainScaleY.f, TerrainScaleXZ.f )
  
  ; we load two textures in to apply to the terrain node
  *TerrainTexture0 = IrrGetTexture( "media\terrain-texture.jpg" )
  *TerrainTexture1 = IrrGetTexture( "media\detailmap3.jpg" )
  
  ; the first texture is a color texture that is applied across the entire
  ; surface of the map. this needs to be a fairly high resoloution as the map is
  ; very large now
  IrrSetNodeMaterialTexture( *TerrainNode, *TerrainTexture0, 0 )
  
  ; the second texture is tiled many times across the map this adds fine detail
  ; and structure to the first enlarged terain color
  IrrSetNodeMaterialTexture( *TerrainNode, *TerrainTexture1, 1 )
  
  ; we set the scale of the detail map so its repeated 20 times across the map in
  ; the x and y axis
  IrrScaleTexture( *terrain, 1.0, 20.0 )
  
  ; finally we apply some material texuring effects to the node
  ; the terrain is self illuminating
  IrrSetNodeMaterialFlag( *TerrainNode, #IRR_EMF_LIGHTING, #IRR_OFF )
  ; the material type is detail type. this type applies the first texture across
  ; the entire node and then scales and applies the second texture across the node
  ; there are many different material types you can set, these can be found in the
  ; .bi definition file, experiment with them
  IrrSetNodeMaterialType ( *TerrainNode, #IRR_EMT_DETAIL_MAP )
  
  ; finally we switch on fog for this material so that this terrain will fade out
  ; into a fog in the distance
  IrrSetNodeMaterialFlag( *TerrainNode, #IRR_EMF_FOG_ENABLE, #IRR_ON )
  
  ; now we need to add the fog to the scene. the first three parameters are the
  ; fog color, we set this to the same color as our sky so the scene fogs out
  ; nicely into nothing, the next parameter specifies whether you want the fog
  ; to increase in a linear mannar or exponentially - exponential fog usually
  ; looks more atmospheric while linear looks more like a dense sea fog, the next
  ; two parameters specify the distance at which the fog starts and the distance
  ; at which the fog reaches its maximum density and finally the fog density -
  ; this is only used with exponential fog and determines how quickly the
  ; exponential change takes place
  IrrSetFog ( 240,240,255,255, #IRR_EXPONENTIAL_FOG, 0.0,8000.0, 0.5 )
  
  
  ; we add a first person perspective camera to the scene so you can look about
  ; and move it into the center of the map
  *camera = IrrAddFPSCamera()
  *CameraNode = *camera
  IrrSetNodePosition( *CameraNode, 3942.8, 1102.7, 5113.9 )
  IrrSetNodeRotation( *CameraNode, 19, -185.5, 0 )
  
  ; the clipping distance of a camera is a distance beyond which no triangles are
  ; rendered, this speeds the scene up by not showing geometry that is in the
  ; distance and too small to see however our terrain is so huge we need to
  ; extend this distance out
  IrrSetCameraClipDistance( *camera, 12000 )
  
  ; we also hide the mouse pointer to see the view better
  IrrHideMouse()
  
  ; Create GUI
  *Status_Terrain  = IrrGuiAddStaticText( "", 4,0,400,16, #IRR_GUI_NO_BORDER, #IRR_GUI_NO_WRAP )
  *Status_Actual   = IrrGuiAddStaticText( "", 4,12,400,28, #IRR_GUI_NO_BORDER, #IRR_GUI_NO_WRAP )
  
  ; Set Static GUI
  IrrGuiSetText(*Status_Terrain, "Terrain Dimensions (X/Z): "+StrF(TerrainWidth.l * TerrainScaleXZ.f)+" * "+StrF(TerrainWidth.l * TerrainScaleXZ.f)+" Y->Height = "+StrF(TerrainWidth.l * TerrainScaleY.f))
  
  ; -----------------------------------------------------------------------------
  ; while the irrlicht environment is still running
  While IrrRunning()
    
      ; Update Status
      IrrGetNodePosition(*camera,@x.f,@y.f,@z.f)
      IrrTerrainHeight(*terrain,x.f,y.f,@Height.f)
      IrrGuiSetText(*Status_Actual, "Actual-> Position: X= "+StrF(x.f)+" Y= "+StrF(y.f)+" Z="+StrF(z.f)+" TerrainHeight: "+StrF(Height.f))
      
      ; begin the scene, erasing the canvas with sky-blue before rendering
      IrrBeginScene( 240, 255, 255 )
  
      ; draw the scene
      IrrDrawScene()
      
      ; Draw the GUI ( Our Status Text in this Case )
      IrrDrawGUI()
      
      ; end drawing the scene and render it
      IrrEndScene()
  Wend
  
  ; -----------------------------------------------------------------------------
  ; Stop the irrlicht engine and release resources
  IrrStop()
  
EndIf 


End

Can i pass a texture pointer to IrrDropPointer() ?!

Yes

Cheers,
Thalius

[Philippe-felixer76]

Hi Phil

About Terrain:
The Terraindimension is the Dimension of your heightmapimagefile^2 multiplied by your nodescale as mike said.

Alternatively where Get and Set height Functions are available one can use The TlT ( TiledTerrain) functions ( which i am playing around currently to docu for the stable ... ).

I found those TlT commands, but i couln't get it working. Hope you can

Can i pass a texture pointer to IrrDropPointer() ?!

Yes

Cheers,
Thalius[/quote]

WOW