What do you mean by "TexEnvCombine::INTERPOLATE actually takes 3 arguments"? Isn't INTERPOLATE an argument to the setCombine_RGB function? I must be missing something...
-----Original Message----- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On Behalf Of Tim Moore Sent: Wednesday, May 23, 2007 1:39 PM To: osg users Subject: Re: [osg-users] TexGenNode & TexEnvCombine -----BEGIN PGP SIGNED MESSAGE----- Hash: SHA1 Weitz, Andrew C. wrote: > I tried a border color with an alpha of 0, but no luck. When I use an > alpha of 0 and enable GL_BLEND, the terrain surrounding my projected > texture becomes invisible. I tried playing with > TexEnvCombine::setCombine_Alpha(), however I haven't been able to get > that to work either. Am I on the right track here? > TexEnvCombine::INTERPOLATE actually takes 3 arguments; you seem to have left the interpolating value out. You can use the alpha channel of your projected texture, including the border color's alpha, if you add tec->setSource2_RGB(osg::TexEnvCombine::TEXTURE); tec->setOperand2_RGB(osg::TexEnvCombine::ONE_MINUS_SRC_ALPHA); To your TexEnvCombine attribute. All untested of course :) Tim > Thanks, > Andrew > > > -----Original Message----- > From: [EMAIL PROTECTED] > [mailto:[EMAIL PROTECTED] On Behalf Of Donald Tidrow > Sent: Wednesday, May 23, 2007 11:17 AM > To: osg users > Subject: Re: [osg-users] TexGenNode & TexEnvCombine > > On Tue, 22 May 2007, Weitz, Andrew C. wrote: > >> Hi, >> >> >> >> I'm having transparency issues that I thought were solvable with a >> TexEnvCombine. However, I cannot figure out the solution. >> >> >> >> I have a scene in which I'm projecting a texture onto terrain that is >> already textured. The terrain is generated with the createBase() >> function in the osgShadowTexture example. I'm projecting another >> texture onto that terrain via a TexGenNode. My projected texture only >> encompasses a small portion of the entire terrain. >> >> >> >> I'd like to control the opacity of my projected texture. I tried > doing >> so with a TexEnvCombine. This seems to work correctly, except that it >> blends the textures on the entire terrain-not just the area where my >> texture is projected. The terrain surrounding the projection area > gets >> blended with my projected texture's border color. This makes me think >> that a solution would be to make my projected texture's border >> transparent. However, I can't figure out how. Relevant code is >> below... >> >> >> >> Is there a way I can only control the opacity/blending only in the > area >> where my texture is projected? >> >> >> >> Thank you, >> >> Andrew >> >> >> >> >> >> // Create the terrain (this uses a texture unit of 0) >> >> osg::ref_ptr<osg::Geode> shadowed = createBase( osg::Vec3(0, 0, 0), 50 >> ); >> >> >> >> // Create the TexGenNode >> >> osg::ref_ptr<osg::TexGenNode> texgenNode = new osg::TexGenNode; >> >> texgenNode->setTextureUnit( 1 ); >> >> texgenNode->getTexGen()->setMode( osg::TexGen::EYE_LINEAR ); >> >> texgenNode->getTexGen()->setPlanesFromMatrix( blah blah blah ); >> >> >> >> // Create the decorator stateset with the projected texture >> >> osg::ref_ptr<osg::StateSet> stateset = new osg::StateSet; >> >> texture->setInternalFormat( GL_RGB/*A*/ ); >> >> texture->setWrap( osg::Texture2D::WRAP_S, >> osg::Texture2D::CLAMP_TO_BORDER ); >> >> texture->setWrap( osg::Texture2D::WRAP_T, >> osg::Texture2D::CLAMP_TO_BORDER ); >> >> texture->setBorderColor( osg::Vec4( 1.0, 0.0, 0.0, 1.0 )); >> > Try setting the border color to something transparent, ie. > osg::Vec4( 1.0, 0.0, 0.0, 0.0 ) > >> stateset->setTextureAttributeAndModes( 1, texture.get(), >> osg::StateAttribute::ON ); >> >> stateset->setTextureMode( texture_unit, GL_TEXTURE_GEN_S, >> osg::StateAttribute::ON ); >> >> stateset->setTextureMode( texture_unit, GL_TEXTURE_GEN_T, >> osg::StateAttribute::ON ); >> >> >> >> // Create the TexEnvCombine >> >> osg::ref_ptr<osg::TexEnvCombine> tec = new osg::TexEnvCombine(); >> >> tec->setCombine_RGB(osg::TexEnvCombine::INTERPOLATE); >> >> tec->setSource0_RGB(osg::TexEnvCombine::TEXTURE); >> >> tec->setSource1_RGB(osg::TexEnvCombine::PREVIOUS); >> >> tec->setOperand0_RGB(osg::TexEnvCombine::SRC_COLOR); >> >> tec->setOperand1_RGB(osg::TexEnvCombine::SRC_COLOR); >> >> tec->setConstantColor(osg::Vec4(0.5, 0.5, 0.5, 0.5 )); >> >> stateset->setTextureAttributeAndModes(1, tec.get(), >> osg::StateAttribute::ON ); >> >> >> >> >> >> >> >> > > --- > In October 1997, three computer lab staffers > disappeared from the server room while debugging > a mysterious router problem. > > One year later, their packet logs were found... > > > The Blair Switch Project > > -------------------- > | Don Tidrow | > | Vis-Sim Geek | > -------------------- > _______________________________________________ > osg-users mailing list > [email protected] > http://openscenegraph.net/mailman/listinfo/osg-users > http://www.openscenegraph.org/ > _______________________________________________ > osg-users mailing list > [email protected] > http://openscenegraph.net/mailman/listinfo/osg-users > http://www.openscenegraph.org/ > -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.4.7 (GNU/Linux) Comment: Using GnuPG with Fedora - http://enigmail.mozdev.org iD8DBQFGVKZseDhWHdXrDRURAp26AKC5MqqD8DRdLg2Cuc7bK8AFCF9/EQCgnnMx 54YDM8sdnCcISbBJlm0Cwb4= =LcrM -----END PGP SIGNATURE----- _______________________________________________ osg-users mailing list [email protected] http://openscenegraph.net/mailman/listinfo/osg-users http://www.openscenegraph.org/ _______________________________________________ osg-users mailing list [email protected] http://openscenegraph.net/mailman/listinfo/osg-users http://www.openscenegraph.org/
