/* -*-c++-*- OpenSceneGraph - Copyright (C) 1998-2003 Robert Osfield * * This library is open source and may be redistributed and/or modified under * the terms of the OpenSceneGraph Public License (OSGPL) version 0.0 or * (at your option) any later version. The full license is in LICENSE file * included with this distribution, and on the openscenegraph.org website. * * This library is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the * OpenSceneGraph Public License for more details. */ #include #include #include #include #include #include #include #include #include #include #include osg::Node* createHUD() { osg::Geode* geode = new osg::Geode(); std::string timesFont("fonts/arial.ttf"); // turn lighting off for the text and disable depth test to ensure its always ontop. osg::StateSet* stateset = geode->getOrCreateStateSet(); stateset->setMode(GL_LIGHTING,osg::StateAttribute::OFF); #if 0 // to ensure the hud appears on top we can either use osg::Depth to force the // depth fragments to be placed at the front of the screen. stateset->setAttribute(new osg::Depth(osg::Depth::LESS,0.0,0.0001)); #else // or disable depth test, and make sure that the hud is drawn after everything // else so that it always appears ontop. stateset->setMode(GL_DEPTH_TEST,osg::StateAttribute::OFF); stateset->setRenderBinDetails(11,"RenderBin"); #endif osg::Vec3 position(150.0f,800.0f,0.0f); osg::Vec3 delta(0.0f,-120.0f,0.0f); { osgText::Text* text = new osgText::Text; geode->addDrawable( text ); text->setFont(timesFont); text->setPosition(position); text->setText("Head Up Displays are simple :-)"); position += delta; } { osgText::Text* text = new osgText::Text; geode->addDrawable( text ); text->setFont(timesFont); text->setPosition(position); text->setText("All you need to do is create your text in a subgraph."); position += delta; } { osgText::Text* text = new osgText::Text; geode->addDrawable( text ); text->setFont(timesFont); text->setPosition(position); text->setText("Disable depth test in this subgraph to ensure its always ontop."); position += delta; } { osgText::Text* text = new osgText::Text; geode->addDrawable( text ); text->setFont(timesFont); text->setPosition(position); text->setText("Then place an osg::Projection node above the subgraph\nto create an orthographic projection."); position += delta; } { osgText::Text* text = new osgText::Text; geode->addDrawable( text ); text->setFont(timesFont); text->setPosition(position); text->setText("And add an osg::ModelViewMatrix set to ABSOLUTE to ensure\nit remains independent from any external model view matrices."); position += delta; } { osg::BoundingBox bb; for(unsigned int i=0;igetNumDrawables();++i) { bb.expandBy(geode->getDrawable(i)->getBound()); } osg::Geometry* geom = new osg::Geometry; osg::Vec3Array* vertices = new osg::Vec3Array; float depth = bb.zMin()-0.1; vertices->push_back(osg::Vec3(bb.xMin(),bb.yMax(),depth)); vertices->push_back(osg::Vec3(bb.xMin(),bb.yMin(),depth)); vertices->push_back(osg::Vec3(bb.xMax(),bb.yMin(),depth)); vertices->push_back(osg::Vec3(bb.xMax(),bb.yMax(),depth)); geom->setVertexArray(vertices); osg::Vec3Array* normals = new osg::Vec3Array; normals->push_back(osg::Vec3(0.0f,0.0f,1.0f)); geom->setNormalArray(normals); geom->setNormalBinding(osg::Geometry::BIND_OVERALL); osg::Vec4Array* colors = new osg::Vec4Array; colors->push_back(osg::Vec4(1.0f,1.0,0.8f,0.2f)); geom->setColorArray(colors); geom->setColorBinding(osg::Geometry::BIND_OVERALL); geom->addPrimitiveSet(new osg::DrawArrays(GL_QUADS,0,4)); osg::StateSet* stateset = geom->getOrCreateStateSet(); stateset->setMode(GL_BLEND,osg::StateAttribute::ON); //stateset->setAttribute(new osg::PolygonOffset(1.0f,1.0f),osg::StateAttribute::ON); stateset->setRenderingHint(osg::StateSet::TRANSPARENT_BIN); geode->addDrawable(geom); } // create the hud. osg::MatrixTransform* modelview_abs = new osg::MatrixTransform; modelview_abs->setReferenceFrame(osg::Transform::RELATIVE_TO_ABSOLUTE); modelview_abs->setMatrix(osg::Matrix::identity()); modelview_abs->addChild(geode); osg::Projection* projection = new osg::Projection; projection->setMatrix(osg::Matrix::ortho2D(0,1280,0,1024)); projection->addChild(modelview_abs); return projection; } 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 how to do Head Up Displays."); arguments.getApplicationUsage()->setCommandLineUsage(arguments.getApplicationName()+" [options] [filename] ..."); arguments.getApplicationUsage()->addCommandLineOption("-h or --help","Display this information"); // construct the viewer. osgProducer::Viewer viewer(arguments); // set up the value with sensible default event handlers. viewer.setUpViewer(osgProducer::Viewer::STANDARD_SETTINGS); // get details on keyboard and mouse bindings used by the viewer. viewer.getUsage(*arguments.getApplicationUsage()); // if user request help write it out to cout. if (arguments.read("-h") || arguments.read("--help")) { arguments.getApplicationUsage()->write(std::cout); return 1; } // any option left unread are converted into errors to write out later. arguments.reportRemainingOptionsAsUnrecognized(); // report any errors if they have occured when parsing the program aguments. if (arguments.errors()) { arguments.writeErrorMessages(std::cout); return 1; } // read the scene from the list of file specified commandline args. osg::ref_ptr scene = osgDB::readNodeFiles(arguments); osg::ref_ptr group = dynamic_cast(scene.get()); if (!group) { group = new osg::Group; group->addChild(scene.get()); } // add the HUD subgraph. group->addChild(createHUD()); // set the scene to render viewer.setSceneData(group.get()); // create the windows and run the threads. viewer.realize(); while( !viewer.done() ) { // wait for all cull and draw threads to complete. viewer.sync(); // update the scene by traversing it with the the update visitor which will // call all node update callbacks and animations. viewer.update(); // fire off the cull and draw traversals of the scene. viewer.frame(); } // wait for all cull and draw threads to complete before exit. viewer.sync(); return 0; }