Am 20.03.2012 09:26, schrieb Daniel Schmid:
I have a hard time understanding that the osgShadow implementations
should support multitexturing when they never mix the colors oft he
different texture units... Ok, I'm not yet that settled in glsl maybe
there is some magic working behind, which I do not understand.
I'm having a closer look right now into StandardShadowMap. There is
only the base texture rendered (which I can define by setter method),
plus the shadow texture. The other textures are ignored. When I want
to use multiple texture layers, I ALWAYS have to write my own shaders.
Is this correct ?
This is correct, also the current implementation doesn't support fog, as
you requested in your first posting.
*Von:*[email protected]
[mailto:[email protected]] *Im Auftrag von
*Sebastian Messerschmidt
*Gesendet:* Dienstag, 20. März 2012 08:18
*An:* OpenSceneGraph Users
*Betreff:* Re: [osg-users] osgShadow and multitexture
Hi Daneil,
All the shadow mapping techniques AFAIR "support" multitexturing.
You will have to provide you custom vertex and fragment shader
however. Also you should set the texture unit/texture coordinates for
the shadow to texture-count + 1.
Just look into the sources, there are the vertex/fragment shaders
you'll need to modify.
I can agree that there currently is no homogeneous way to setup
shaders for all the techniques, but it can be done.
For the vertex shader, you will have to assign something the eye-space
coordinates to the texture unit.
For shadow mapping it more or less boils down to:
gl_MultiTexCoord[n].s = dot(gl_EyePlaneS[n] * gl_Vertex);
gl_MultiTexCoord[n].t = dot(gl_EyePlaneT[n] * gl_Vertex);
gl_MultiTexCoord[n].p = dot(gl_EyePlaneP[n] * gl_Vertex);
gl_MultiTexCoord[n].q = dot(gl_EyePlaneQ[n] * gl_Vertex);
The fragment shader you can get from the sources.
cheers
Sebastian
Hi Robert
Thanks for your answer. I was hoping all osgShadow techniques support
multi-texturing... but in my application, i tried every single one,
and I only have strange effects. What happens basically is the
following: I can manage to have a shadow with standardshadowmap, and
all the view based techniques, by selecting the base texture unit as 0
and the shadow texture unit between 1 and 4. What happens then is that
the according texture level of my model is replaced with my shadow
texture and the texture coordinates of this level get mixed up, like i
have other textures moving when rotating my viewport. So I thought,
probably these levels are already occupied by my scene model, so I
have to use a value above 4, but then I have no more shadow displayed
at all.
I'm sure I'm missing somehow an important point about the way base
texture and shadow texture units must have been supposed to use. But
after some days of try and error, I cannot figure how I can have osg
create a shadow without removing my textures or messing with a
textures layer coordinate...
I'm really stuck... help appreciated. There are not really any
tutorials out there explaining the use of osgShadow...
Regards
Daniel
_______________________________________________
osg-users mailing list
[email protected] <mailto:[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
_______________________________________________
osg-users mailing list
[email protected]
http://lists.openscenegraph.org/listinfo.cgi/osg-users-openscenegraph.org
