Hi Wyatt,

Yes,thats a good picture. What it tells me:

1. Light node has been found and direction seem to be computed correctly.
2. Shadow map seems correct. Only back faces from light perspective are 
rendered.  These are the faces that are casting shadows. This is exactly what 
Lispsm sets.

Since ShadowMap rendering seems correct you most probably have an issue with 
application of shadow map to final scene.

Here is a check list to iterate.

1: Check your texcoords and texstages and verify if there is no conflict of 
some other texture with shadow map stage/coords. 
2: Check your shaders if they compile and use the same shadow map uniforms 
/shadow coords correctly. Try turning shaders off. Lispsm shadows should work  
even with fixed pipeline. Usually shadows become almost black but they are 
visible.
3: If you use vertex shader check materials used for terrain and buildings. 
Vertex shaders do not work correctly with materials using COLOR_MATERIAL 
attribute ie some material components are defined through vertex colors. Your 
material should have COLOR_MATERIAL mode set to off and 
diffuse/ambient/specular components should be defined in material not in 
promitive colors. COLOR_MATERIAL mode is notorious for the problems with 
shadows.  Its not supported by shaders. Works with fixed pipeline only. Best 
solution is to convert (osgconv) your model file into text .osg format and 
examine states it uses in text editor.  

If this does not help, consider sending a piece of your code and models.

Cheers,
Wojtek

From: Wyatt Earp 
Sent: Friday, November 20, 2009 6:03 AM
To: 'OpenSceneGraph Users' 
Cc: 'Wojciech Lewandowski' 
Subject: RE: [osg-users] ShadowMap problem...


Is this what you meant?

Thanks,

W

 

 

 

From: [email protected] 
[mailto:[email protected]] On Behalf Of Wojciech 
Lewandowski
Sent: Thursday, November 19, 2009 4:56 PM
To: 'OpenSceneGraph Users'
Subject: Re: [osg-users] ShadowMap problem...

 

Hi Wyatt,

 

Buildings getting darker while light is moving can be a normal thing it is 
simply a result of normal diffuse shading. Can you move camera so close that 
view frustum contains a single building ?. Ideally make it look at 45 deg from 
a liitle above. Then make screenshot, with debugHUD. Its really important whats 
on debug hud display.  This will tell me alot. If you have problems with 300 kb 
OSG forum limit, just send this screenshot directly to my address. 

 

Cheers,

Wojtek Lewandowski

 

 

 

From: Wyatt Earp 

Sent: Thursday, November 19, 2009 10:45 PM

To: 'OpenSceneGraph Users' 

Subject: Re: [osg-users] ShadowMap problem...

 

Ok... so I did what you suggested mostly... I took the osgshadow example, add 
my geometry and it worked.  I added another shader on the root node of the 
scenegraph, because in my app, I do that.  I took the shaders from 
ShadowMap.cpp and put them into vert/frag files and loaded them into their 
respective shaders.  That worked too.

 

In my application, when I load those shaders from ShadowMap.cpp and use them, I 
see a change in the lighting but it isn't what I expect.  Rather than the 
objects casting shadows on the terrain, it looks like a shdow is being cast 
over the objects, but it isnt'being cast on the terrain.  The best way I can 
describe it is that it looks like the objects are in the sun then a cloud 
floats between the sun and the object...  I don't think a picture will show 
what I mean, but here are 3 pictures with the shadow moving progressively to 
the left over the object... note the white building in the front gets darker.  
But now shadows on the terrain.

 



 



 

 



 

W

 

 

 

> -----Original Message-----

> From: [email protected] [mailto:osg-users-

> [email protected]] On Behalf Of Jean-Sébastien Guay

> Sent: Thursday, November 12, 2009 1:45 PM

> To: OpenSceneGraph Users

> Subject: Re: [osg-users] ShadowMap problem...

> 

> Hi Wyatt,

> 

> > Any suggestions?

> 

> Not really. At this point you'll probably have to trace into OSG to

> make

> sure the shadow map traversal is getting to the right objects (i.e.

> your

> masks are set correctly), and check your shaders (perhaps even try with

> the basic shaders that LISPSM uses by default for starters). Also, try

> to start with the osgShadow example, and work up progressively to

> something similar to what you have in your app, and perhaps in the

> process you'll find out what's not working. If not, then at least

> you'll

> have a small app that can demonstrate the problem, which we might be

> able to help with.

> 

> Hope this helps,

> 

> J-S

> --

> ______________________________________________________

> Jean-Sebastien Guay    [email protected]

>                                 http://www.cm-labs.com/

>                          http://whitestar02.webhop.org/

> _______________________________________________

> osg-users mailing list

> [email protected]

> http://lists.openscenegraph.org/listinfo.cgi/osg-users-

> openscenegraph.org


--------------------------------------------------------------------------------

_______________________________________________
osg-users mailing list
[email protected]
http://lists.openscenegraph.org/listinfo.cgi/osg-users-openscenegraph.org

<<image001.jpg>>

<<image002.jpg>>

<<image003.jpg>>

_______________________________________________
osg-users mailing list
[email protected]
http://lists.openscenegraph.org/listinfo.cgi/osg-users-openscenegraph.org

Reply via email to