[osg-users] RTT and stereo (revisited)...

Farshid Lashkari flashk at gmail.com
Wed Oct 10 15:54:16 PDT 2007


Hi Mike

You need to set the left/right cull masks on the SceneView. Then set
the node masks for each camera to the appropriate cull mask. I've
successfully used this technique to render camera nodes in stereo.

-Farshid

On 10/10/07, Mike Logan <mlogan at mail.arc.nasa.gov> wrote:
>
>
> ahem..  Looking for some free debugging.. 8)
>
> I've included a very slimmed down & modified osgprerender.cpp
>  example with a second camera added in an attempt to
> get stereo-rtt working..
>
> I've discovered that the
>  RenderImplementation = osg::Camera::SEPERATE_WINDOW
> is a very useful tool (run with the --window option).
>
> It seems to show that the program is basically working
>  in stereo but the final main window only shows the "right" eye.
>
> I've tried this on OSX (anaglyph) and Linux (quad-buffer) and
>  they perform roughtly the same.   (OSG-SVN 2.2.10+  or so)
>
> Anyone done this already with the SVN version?
> See anything obvious?
>
> ml
>
>
> #include <osg/GLExtensions>
> #include <osg/DrawPixels>
> #include <osg/Node>
> #include <osg/Geometry>
> #include <osg/Notify>
> #include <osg/MatrixTransform>
> #include <osg/Texture2D>
> #include <osg/TextureRectangle>
> #include <osg/Stencil>
> #include <osg/ColorMask>
> #include <osg/Depth>
> #include <osg/Billboard>
> #include <osg/Material>
> #include <osg/AnimationPath>
>
> #include <osgGA/TrackballManipulator>
> #include <osgGA/FlightManipulator>
> #include <osgGA/DriveManipulator>
>
> #include <osgUtil/SmoothingVisitor>
>
> #include <osgDB/Registry>
> #include <osgDB/ReadFile>
>
> #include <osgViewer/Viewer>
>
> #include <iostream>
>
>
>
> osg::Camera*
> create_camera( const int& eye, const osg::BoundingSphere& bs,
>         unsigned int tex_width,
>         unsigned int tex_height,
>         osg::Camera::RenderTargetImplementation
> renderImplementation )
>
> {
>         osg::Camera* camera = new osg::Camera;
>
>         // set up the background color and clear mask.
>
> //camera->setClearColor(osg::Vec4(0.1f,0.1f,0.3f,1.0f));
>         camera->setClearMask(GL_COLOR_BUFFER_BIT |
> GL_DEPTH_BUFFER_BIT);
>
>         float znear = 1.0f*bs.radius();
>         float zfar  = 3.0f*bs.radius();
>
>         // 2:1 aspect ratio as per flag geometry above.
>         float proj_top   = 0.25f*znear;
>         float proj_right = 0.5f*znear;
>         // 1:1 aspect ratio as per flag geometry above.
>         /*mal*/proj_top   = 1.0f*znear;
>         /*mal*/proj_right = 1.0f*znear;
>
>         znear *= 0.9f;
>         zfar *= 1.1f;
>
>         // set up projection.
>
> camera->setProjectionMatrixAsFrustum(-proj_right,proj_right,-proj_top,proj_top,znear,zfar);
>
>         // set view
>
> camera->setReferenceFrame(osg::Transform::ABSOLUTE_RF);
>         camera->setViewMatrixAsLookAt(
> bs.center()-osg::Vec3(0.0f,1.0f,0.0f)*bs.radius(),
>                                        bs.center(),
>                                        osg::Vec3(0.0f,0.0f,1.0f));
>
>         // set viewport
>         camera->setViewport(0,0,tex_width,tex_height);
>
>         // set stereo parameters
>
>         camera->setCullMaskLeft( 0x1 );
>         camera->setCullMaskRight( 0x2 );
>
>         switch( eye ) {
>             case 0:
>
> camera->setClearColor(osg::Vec4(0.3f,0.3f,0.1f,1.0f));
>                 break;
>             case 0x1:
>                 camera->setCullMask( 0x1 );
>
> //camera->setViewport(0,0,tex_width/2,tex_height/2);
>
> camera->setClearColor(osg::Vec4(0.3f,0.1f,0.1f,1.0f));
>         camera->setViewMatrixAsLookAt(
> bs.center()-osg::Vec3(0.1f,1.0f,0.0f)*bs.radius(),
>                                        bs.center(),
>                                        osg::Vec3(0.0f,0.0f,1.0f));
>                 break;
>             case 0x2:
>                 camera->setCullMask( 0x2 );
>
> //camera->setViewport(tex_width/2,0,tex_width/2,tex_height/2);
>
> camera->setClearColor(osg::Vec4(0.1f,0.1f,0.3f,1.0f));
>         camera->setViewMatrixAsLookAt(
> bs.center()-osg::Vec3(-0.1f,1.0f,0.0f)*bs.radius(),
>                                        bs.center(),
>                                        osg::Vec3(0.0f,0.0f,1.0f));
>                 break;
>         }
>
>         // set the camera to render before the main camera.
>         camera->setRenderOrder(osg::Camera::PRE_RENDER);
>
>         // tell the camera to use OpenGL frame buffer object where
> supported.
>
> camera->setRenderTargetImplementation(renderImplementation);
>
>         return camera;
> }
>
> osg::Node*
> createPreRenderSubGraph(
>       osg::Node* subgraph,
>       unsigned int tex_width,
>       unsigned int tex_height,
>       osg::Camera::RenderTargetImplementation
> renderImplementation)
>
> {
>     if (!subgraph) return 0;
>
>     // create a group to contain the flag and the pre rendering camera.
>     osg::Group* parent = new osg::Group;
>
>     // texture to render to and to use for rendering of flag.
>
>     osg::Texture* texture = 0;
>     osg::Texture2D* texture2D = new osg::Texture2D;
>     texture2D->setTextureSize(tex_width, tex_height);
>     texture2D->setInternalFormat(GL_RGBA);
>
> texture2D->setFilter(osg::Texture2D::MIN_FILTER,osg::Texture2D::LINEAR);
>
> texture2D->setFilter(osg::Texture2D::MAG_FILTER,osg::Texture2D::LINEAR);
>     texture = texture2D;
>
>     //
>     // create the object on which to drape our rendered 'canvas'..
>     //
>         osg::Geometry* polyGeom = new osg::Geometry();
>
>         polyGeom->setSupportsDisplayList(false);
>
>         osg::Vec3 origin(0.0f,0.0f,0.0f);
>         osg::Vec3 xAxis(1.0f,0.0f,0.0f);
>         osg::Vec3 yAxis(0.0f,0.0f,1.0f);
>         osg::Vec3 zAxis(0.0f,-1.0f,0.0f);
>         int noSteps = 20;
>
>         float width  = 200.0f;
>         float height = 100.0f;
>         /*mal*/width  = 256.0f;
>         /*mal*/height = 256.0f;
>
>
>         osg::Vec3Array* vertices = new osg::Vec3Array;
>         osg::Vec3 bottom = origin;
>         osg::Vec3 top = origin;   top.z()+= height;
>         osg::Vec3 dv = xAxis*(width/((float)(noSteps-1)));
>
>         osg::Vec2Array* texcoords = new osg::Vec2Array;
>
>         // set the tex coords.
>         osg::Vec2 bottom_texcoord(0.0f,0.0f);
>         osg::Vec2 top_texcoord(0.0f, 1.0f);
>         osg::Vec2 dv_texcoord(1.0f/(float)(noSteps-1),0.0f);
>
>         for(int i=0;i<noSteps;++i)
>         {
>             vertices->push_back(top);
>             vertices->push_back(bottom);
>             top+=dv;
>             bottom+=dv;
>
>             texcoords->push_back(top_texcoord);
>             texcoords->push_back(bottom_texcoord);
>             top_texcoord+=dv_texcoord;
>             bottom_texcoord+=dv_texcoord;
>         }
>
>
>         // pass the created vertex array to the points geometry object.
>         polyGeom->setVertexArray(vertices);
>
>         polyGeom->setTexCoordArray(0,texcoords);
>
>         osg::Vec4Array* colors = new osg::Vec4Array;
>         colors->push_back(osg::Vec4(1.0f,1.0f,1.0f,1.0f));
>         polyGeom->setColorArray(colors);
>
> polyGeom->setColorBinding(osg::Geometry::BIND_OVERALL);
>
>         polyGeom->addPrimitiveSet(new
> osg::DrawArrays(osg::PrimitiveSet::QUAD_STRIP,0,vertices->size()));
>
>         // Now we need to add the texture to the Drawable. Do so by creating
> a
>         // StateSet to contain the Texture StateAttribute.
>         osg::StateSet* stateset = new osg::StateSet;
>         stateset->setTextureAttributeAndModes(0,
> texture,osg::StateAttribute::ON);
>
>         polyGeom->setStateSet(stateset);
>         osgUtil::SmoothingVisitor::smooth( *polyGeom );
>         osg::Geode* geode = new osg::Geode();
>         geode->addDrawable(polyGeom);
>         parent->addChild(geode);
>
>
>     //
>     // Then create the camera node to do the render to texture
>     //
>
>     {
>         const osg::BoundingSphere& bs = subgraph->getBound();
>         if (!bs.valid()) {
>             return subgraph;
>         }
>
>         osg::Camera* Lcamera = create_camera( 0x01, bs,  tex_width,
> tex_height,  renderImplementation );
>         osg::Camera* Rcamera = create_camera( 0x02, bs,  tex_width,
> tex_height,  renderImplementation );
>
>
>             // attach the texture and use it as the color buffer.
>           Lcamera->attach(osg::Camera::COLOR_BUFFER,
> texture);
>           Rcamera->attach(osg::Camera::COLOR_BUFFER,
> texture);
>
>         // add subgraph to render
>         Lcamera->addChild(subgraph);
>         Rcamera->addChild(subgraph);
>         parent->addChild(Lcamera);
>         parent->addChild(Rcamera);
>
>     }
>
>     return parent;
> }
>
> int main( int argc, char **argv )
> {
>     // use an ArgumentParser object to manage the program arguments.
>     osg::ArgumentParser arguments(&argc,argv);
>
>     // set up the usage document, in case we need to print out how to use
> this program.
>
> arguments.getApplicationUsage()->setDescription(arguments.getApplicationName()+"
> is the example which demonstrates pre rendering of scene to a texture, and
> then apply this texture to geometry.");
>
> arguments.getApplicationUsage()->setCommandLineUsage(arguments.getApplicationName()+"
> [options] filename ...");
>     arguments.getApplicationUsage()->addCommandLineOption("-h or
> --help","Display this information");
>
> arguments.getApplicationUsage()->addCommandLineOption("--fbo","Use
> Frame Buffer Object for render to texture, where supported.");
>
> arguments.getApplicationUsage()->addCommandLineOption("--fb","Use
> FrameBuffer for render to texture.");
>
> arguments.getApplicationUsage()->addCommandLineOption("--pbuffer","Use
> Pixel Buffer for render to texture, where supported.");
>
> arguments.getApplicationUsage()->addCommandLineOption("--window","Use
> a seperate Window for render to texture.");
>
> arguments.getApplicationUsage()->addCommandLineOption("--width","Set
> the width of the render to texture.");
>
> arguments.getApplicationUsage()->addCommandLineOption("--height","Set
> the height of the render to texture.");
>
> arguments.getApplicationUsage()->addCommandLineOption("--image","Render
> to an image, then apply a post draw callback to it, and use this image to
> update a texture.");
>
> arguments.getApplicationUsage()->addCommandLineOption("--texture-rectangle","Use
> osg::TextureRectangle for doing the render to texure to.");
>
> arguments.getApplicationUsage()->addCommandLineOption("--draw","Use
> drawpixels and no texturing at all.");
>
>     // construct the viewer.
>     osgViewer::Viewer viewer(arguments);
>
>     // if user request help write it out to cout.
>     if (arguments.read("-h") || arguments.read("--help"))
>     {
>         arguments.getApplicationUsage()->write(std::cout);
>         return 1;
>     }
>
>     unsigned tex_width  = 256;
>     unsigned tex_height = 256;
>     while (arguments.read("--width", tex_width)) {}
>     while (arguments.read("--height", tex_height)) {}
>
>     osg::Camera::RenderTargetImplementation
> renderImplementation = osg::Camera::FRAME_BUFFER_OBJECT;
>
>     while (arguments.read("--fbo")) { renderImplementation =
> osg::Camera::FRAME_BUFFER_OBJECT; }
>     while (arguments.read("--pbuffer")) { renderImplementation =
> osg::Camera::PIXEL_BUFFER; }
>     while (arguments.read("--pbuffer-rtt")) { renderImplementation =
> osg::Camera::PIXEL_BUFFER_RTT; }
>     while (arguments.read("--fb")) { renderImplementation =
> osg::Camera::FRAME_BUFFER; }
>     while (arguments.read("--window")) { renderImplementation =
> osg::Camera::SEPERATE_WINDOW; }
>
>     // load the nodes from the commandline arguments.
>     osg::Node* loadedModel =
> osgDB::readNodeFiles(arguments);
>
>     // if not loaded assume no arguments passed in, try use default mode
> instead.
>     if (!loadedModel) loadedModel = osgDB::readNodeFile("cessna.osg");
>
>     if (!loadedModel)
>     {
>         return 1;
>     }
>
>     osg::Group* rootNode = new osg::Group();
> #if no_spinning
>     // create a transform to spin the model.
>     osg::MatrixTransform* loadedModelTransform = new osg::MatrixTransform;
>     loadedModelTransform->addChild(loadedModel);
>
>     osg::NodeCallback* nc =
>       new
> osg::AnimationPathCallback(loadedModelTransform->getBound().center(),
>                                      osg::Vec3(0.0f,0.0f,1.0f),
>                                      osg::inDegrees(45.0f));
>     loadedModelTransform->setUpdateCallback(nc);
>
>     rootNode->addChild(
> createPreRenderSubGraph(loadedModelTransform,
>                                                 tex_width,tex_height,
>                                                 renderImplementation ) );
> #else
>     rootNode->addChild(
> createPreRenderSubGraph(loadedModel,
>                                                 tex_width,tex_height,
>                                                 renderImplementation ));
> #endif
>
>     // add model to the viewer.
>     viewer.setSceneData( rootNode );
>
>     return viewer.run();
> }
>
>
>
>
>
>
> Michael Logan
>
> Perot Systems Govt. Services / NASA Ames Res. Ctr.
>
> MS 269-1, Moffett Field, CA, 94035  (650)-604-4494
>
> Task Lead                       - Visual Cueing & Simulation
>
> Task Lead                       - Human Manual & Operational Control
> Performance
>
> Visualization Engineer - Adaptive Control Technologies
> "If you want to start a revolution, don't pick up a gun.
>  Do it with science and technology."  - Stanford R. Ovshinsky
>
>
> _______________________________________________
> osg-users mailing list
> osg-users at lists.openscenegraph.org
> http://lists.openscenegraph.org/listinfo.cgi/osg-users-openscenegraph.org
>
>



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