Its kind of tough to say without having a good idea about what exactly you can
do with your plugin. I can say what you most likely need to do is to bind a
texture with your blend map to your scene some how.
Ideally you would do this in a 2nd rendering pass. Basically you want to
perform blending on a final image.
In your fragment shader you can use gl_FragCoord, this will get you the screen
coordinate of the current fragment (basically pixel). Then you can use
texelFetch to lookup a scaler for your output pixel. For example if you had
this function you called last in your fragment shader:
uniform sampler2D blendTexture;
void BlendFunct(inout vec4 color){
vec4 blendVal = texalFetch(blendTexture,gl_FragCoord.xy,0);
color.rgb = color.rgb * blendVal.rgbl;
}
In practical terms you often have to deal with the gamma settings for your
projectors, and things are not always linear. When you have things in your
scene with transparency were things get blended together, its ideal to do a
multi-pass rendering.
------------------
Read this topic online here:
http://forum.openscenegraph.org/viewtopic.php?p=68835#68835
_______________________________________________
osg-users mailing list
osg-users@lists.openscenegraph.org
http://lists.openscenegraph.org/listinfo.cgi/osg-users-openscenegraph.org
