Hi, In fact I export blender object to .3ds file by using blender export function. To check if the probleme comes from this export function, I exported also my object to .ac (AC3D) file format. To obtain the same view of my "IMS" square (I want my camera in front of the square, not above), I have to change the position of my camera from (0, 0, -20) to (0, 20, 0), so it seems that the frame of ac3d is rotated from -90° around X-axis. Because of this axis rotation, I have dispaced my Light to the position (0, 15,20) to recreate the same scene than with the .3ds object. The results are totally different. I have attached four image to this mail. The first is the result obtained with .3ds file. The second is the result if I use .ac file without changing camera position. The third is the result obtained by changing camera position. And the fourth is the result when I changed camera position and light position.
It seems, that with AC3D file (.ac), I have not the probleme of the "bottom-left corner". But the black color of the square around the IMS text is become grey! When I displace the light , the square seems to be less enlighten. I don't understand why... Have anybody had the same kind of problem? Jean-Baptiste. 2008/6/18 Paul Melis <[EMAIL PROTECTED]>: > Jean-Baptiste Authesserre wrote: > >> This is the result when I remove the helmet. I really don(t understand. >> The square is obtained thanks to the following way. I ceated a cube with >> blender 3*3*0.1 (small depth along th Z-axis) >> I load on that cube a texture. I attach to this mail the result without >> the helmet and the texture attached to the cube. >> It's very strange... >> > You can check the .osg file exported by Blender to see if the normals are > set correctly. There shouldn't be that many for this simple model I suspect. > > Paul > > >> 2008/6/18 Paul Melis <[EMAIL PROTECTED] <mailto:[EMAIL PROTECTED]>>: >> >> Jean-Baptiste Authesserre wrote: >> >> 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? >> >> Ah! You said "my object isn't uniformly enlighten" in your >> original mail. With "object" I figured you meant the whole >> thing/"helmet". I now see what you mean w.r.t. the dark corner on >> the square. Could it be that you have an incorrect normal for that >> corner of the square? Are the square and helmet one object? Does >> it still show when you display only the square (i.e. could it be >> an artifact that actually comes from the helmet, and not the square)? >> >> Paul >> >> >> Jean-Baptiste >> >> 2008/6/18 Jean-Baptiste Authesserre <[EMAIL PROTECTED] >> <mailto:[EMAIL PROTECTED]> <mailto:[EMAIL PROTECTED] >> <mailto:[EMAIL PROTECTED]>>>: >> >> >> Hi, >> >> I am a little confused. My camera >> >> 2008/6/18 Paul Melis <[EMAIL PROTECTED] >> <mailto:[EMAIL PROTECTED]> >> <mailto:[EMAIL PROTECTED] <mailto:[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 >> [email protected] >> <mailto:[email protected]> >> <mailto:[email protected] >> <mailto:[email protected]>> >> >> >> http://lists.openscenegraph.org/listinfo.cgi/osg-users-openscenegraph.org >> >> _______________________________________________ >> osg-users mailing list >> [email protected] >> <mailto:[email protected]> >> <mailto:[email protected] >> <mailto:[email protected]>> >> >> >> http://lists.openscenegraph.org/listinfo.cgi/osg-users-openscenegraph.org >> >> >> >> >> ------------------------------------------------------------------------ >> >> _______________________________________________ >> 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] >> <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 >
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