Sorry for the previous mail. I'm a little confused. My camera is configured to take Y-axis as UP axis. In my 3D-model, I put the helmet so that the bottom of the helmet correspond to negative Y, and the top to positive Y (cf attached figure). The camera look at (0, 0, 0). Thus I can obtain the attached image. To enlight the scene I put the light at 0 on X-axis so the region around the bottom corners of the square be enlighten the same way (the square is in the XY plane). However the region around bottom-left corner is darker than the region around bottom-right corner. What have I missed?
Jean-Baptiste 2008/6/18 Jean-Baptiste Authesserre <[EMAIL PROTECTED]>: > Hi, > > I am a little confused. My camera > > 2008/6/18 Paul Melis <[EMAIL PROTECTED]>: > > Jean-Baptiste Authesserre wrote: >> >>> Hi everyone, >>> >>> I have some problem with OSG Light, and I don't find answer in the osg >>> archives. My problem is the following : I don't understand why with the >>> following code my object isn't uniformly enlighten. (cf. image in attached >>> document) >>> -The black and white square of the image is centered at (0, 0, 0) (in >>> world frame with convention (x, y, z)) >>> -The camera is located at (0, 0, -20) >>> -the light is located at (0,20, -15) >>> >> If you didn't change this yourself then +Z will be the up axis, btw >> >>> >>> >>> The code for activating light is the following: >>> >>> /***************************** >>> ** light *************************************/ >>> >>> >>> //Creation of light source >>> osg::Light* light = new osg::Light(); >>> osg::LightSource * lightsource = new osg::LightSource(); >>> lightsource->setLight(light); >>> // put the light source in the scenegraph >>> root->addChild(lightsource); >>> >>> // turn light on >>> osg::StateSet * stateset = root->getOrCreateStateSet(); >>> lightsource->setStateSetModes(*stateset, osg::StateAttribute::ON); >>> light->setAmbient(osg::Vec4d(1.0, 1.0, 1.0, 1.0)); >>> //light->setDiffuse(osg::Vec4d(0.0, 0.0, 0.0, 0.0)); >>> //light->setSpecular(osg::Vec4d(1.0, 1.0, 1.0, 1.0)); >>> light->setPosition(osg::Vec4d(0.0, 20.0, -15.0, 1.0)); >>> >>> >>> /******************************************************************************/ >>> >>> So, I don't understand why the bottom-left corner of my square is darker >>> than the others corners >>> >> I don't see any difference here between left and right bottom corners, >> they're equally dark IMHO. Which seems to make sense, as you've put the >> light source above and little in front of the camera, but in the center of >> the object (the X plane). >> >> Paul >> >>> Has anybody an Idea? >>> >>> >>> Best regards, >>> >>> Jean-Baptiste. >>> ------------------------------------------------------------------------ >>> >>> _______________________________________________ >>> osg-users mailing list >>> osg-users@lists.openscenegraph.org >>> http://lists.openscenegraph.org/listinfo.cgi/osg-users-openscenegraph.org >>> >>> >> >> _______________________________________________ >> osg-users mailing list >> osg-users@lists.openscenegraph.org >> http://lists.openscenegraph.org/listinfo.cgi/osg-users-openscenegraph.org >> > >
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