Hi, I have resolved the problem, I found out that there is a class which helps changing projection, that is osg::Projection which provides different projections for the same camera.
--- On Sat, 12/27/08, guher b <[email protected]> wrote: > From: guher b <[email protected]> > Subject: [osg-users] Both orthographic and perspective projections for the > same camera > To: [email protected] > Date: Saturday, December 27, 2008, 8:17 PM > Hi, > > while trying to implement rtt textures, > I came a cross a situation that I can not solve in anyway. > A camera (this camera is a post render camera (which was > added to scenegraph) which draws to frame buffer.and > meanwhile, the main camera (of the viewer) produces a > texture (via fbo) that this camera uses to draw to frame > buffer) > > This camera(post render camera) should draw two different > geometries; a simple quad, which is used to render a > textured quad with orthographic projection (to draw the main > camera's fbo's generated texture in to the frame > buffer), and secondly a geometry(a sphere) with perspective > projection to be drawn to the frame buffer afterwards. > > To handle different projections, I reimplemented the > drawcallback of the first geometry (which needed > orthographic projection) and did nothing for the sphere > which used the camera's original projection (perspective > projection). However, when the sphere is visible, sphere is > not rendered as it should be, the whole scene becomes the > sphere's color, when the sphere is visible, and nothing > is drawn when the sphere is not visible. There is no sphere > shape at all. I belive that the drawcallback of the first > geometry does something wrong which produces this behavior, > cause when the drawcallback is not done, the first geom is > not drawn but the sphere is drawn as it should be. The > following code shows my drawcallback of the first geometry, > class TmpDrawCallback : public osg::Drawable::DrawCallback > { > public: > TmpDrawCallback() : > osg::Drawable::DrawCallback(){ > projectionMatrix=new > osg::RefMatrix(osg::Matrix::ortho(0,1,0,1,0,1)); > osg::Matrix m; > > m.getLookAt(osg::Vec3d(0,0,0),osg::Vec3d(0,0,-2),osg::Vec3d(0,1,0)); > modelViewMatrix=new osg::RefMatrix(m); > } > ~TmpDrawCallback() {} > > void drawImplementation > (osg::RenderInfo& ri, const osg::Drawable* dr) const; > osg::RefMatrix * projectionMatrix; > osg::RefMatrix * modelViewMatrix; > > > > > }; > void TmpDrawCallback::drawImplementation > (osg::RenderInfo& ri, const osg::Drawable* dr) const > { > osg::RefMatrix * originalPm=new > osg::RefMatrix(ri.getState()->getProjectionMatrix()); > osg::RefMatrix * originalMvm=new > osg::RefMatrix(ri.getState()->getModelViewMatrix()); > > ri.getState()->applyProjectionMatrix(projectionMatrix); > ri.getState()->applyModelViewMatrix(modelViewMatrix); > > dr->drawImplementation(ri); > > ri.getState()->applyProjectionMatrix(originalPm); > ri.getState()->applyModelViewMatrix(originalMvm); > } > > > Does anyone see the flaw here? Or, is there any other way > of implementing 2 different projections for the > samecamera(without reimplementing the drawcallback)? > Thanks in advance > > > > > > > _______________________________________________ > 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
