One of the most widely used node type families in osg, application examples of osg::autoTransform are as follows:
#include <osgUtil/Optimizer>
#include <osgDB/ReadFile>
#include <osgGA/TrackballManipulator>
#include <osgViewer/ViewerEventHandlers>
#include <osgViewer/CompositeViewer>
#include <osg/Material>
#include <osg/Geode>
#include <osg/BlendFunc>
#include <osg/Depth>
#include <osg/Projection>
#include <osg/AutoTransform>
#include <osg/Geometry>
#include <osgDB/WriteFile>
#include <osgText/Text>
#include <iostream>
osg::Node* createLabel(const osg::Vec3 & amp; pos, float size, const std::string & amp; label, osgText::Text::AxisAlignment axisAlignment)
{<!-- -->
osg::Geode* geode = new osg::Geode();
std::string timesFont("fonts/arial.ttf");
{<!-- -->
osgText::Text* text = new osgText::Text;
geode->addDrawable( text );
text->setFont(timesFont);
text->setPosition(pos);
text->setCharacterSize(size);
text->setAxisAlignment(axisAlignment);
text->setAlignment(osgText::Text::CENTER_CENTER);
text->setText(label);
}
return geode;
}
osg::Node* createLabel3(const osg::Vec3 & amp; pos, float size, const std::string & amp; label)
{<!-- -->
osg::Geode* geode = new osg::Geode();
std::string timesFont("fonts/arial.ttf");
{<!-- -->
osgText::Text* text = new osgText::Text;
geode->addDrawable( text );
text->setFont(timesFont);
text->setPosition(pos);
text->setFontResolution(40,40);
text->setCharacterSize(size);
text->setAlignment(osgText::Text::CENTER_CENTER);
text->setAutoRotateToScreen(true);
text->setCharacterSizeMode(osgText::Text::OBJECT_COORDS_WITH_MAXIMUM_SCREEN_SIZE_CAPPED_BY_FONT_HEIGHT);
text->setText(label);
}
return geode;
}
osg::Node* createAxis(const osg::Vec3 & amp; s, const osg::Vec3 & amp; e, int numReps, osg::AutoTransform::AutoRotateMode autoRotateMode, osgText::Text::AxisAlignment axisAlignment, const std ::string & str)
{<!-- -->
osg::Group* group = new osg::Group;
osg::Vec3 dv = e-s;
dv /= float(numReps-1);
osg::Vec3 pos = s;
bool useAuto = true;
if(useAuto)
{<!-- -->
osg::Vec3Array* vertices = new osg::Vec3Array;
for(int i=0;i<numReps; + + i)
{<!-- -->
osg::AutoTransform* at = new osg::AutoTransform;
at->setPosition(pos);
at->setAutoRotateMode(autoRotateMode);
at->addChild(createLabel(osg::Vec3(0.0f,0.0f,0.0f),dv.length()*0.2f,str, axisAlignment));
vertices->push_back(pos);
pos + = dv;
group->addChild(at);
}
osg::Vec4Array* colors = new osg::Vec4Array;
colors->push_back(osg::Vec4(1.0f,1.0f,1.0f,1.0f));
osg::Geometry* geom = new osg::Geometry;
geom->setVertexArray(vertices);
geom->setColorArray(colors, osg::Array::BIND_OVERALL);
geom->addPrimitiveSet(new osg::DrawArrays(GL_LINE_STRIP,0,vertices->size()));
osg::Geode* geode = new osg::Geode;
geode->addDrawable(geom);
group->addChild(geode);
}
else
{<!-- -->
osg::Vec3Array* vertices = new osg::Vec3Array;
for(int i=0;i<numReps; + + i)
{<!-- -->
group->addChild(createLabel3(osg::Vec3(pos),dv.length()*0.5f,str));
vertices->push_back(pos);
pos + = dv;
}
osg::Vec4Array* colors = new osg::Vec4Array;
colors->push_back(osg::Vec4(1.0f,1.0f,1.0f,1.0f));
osg::Geometry* geom = new osg::Geometry;
geom->setVertexArray(vertices);
geom->setColorArray(colors, osg::Array::BIND_OVERALL);
geom->addPrimitiveSet(new osg::DrawArrays(GL_LINE_STRIP,0,vertices->size()));
osg::Geode* geode = new osg::Geode;
geode->addDrawable(geom);
group->addChild(geode);
}
return group;
}
osg::Node* createAutoScale(const osg::Vec3 & amp; position, float characterSize, const std::string & amp; message, float minScale=0.0, float maxScale=FLT_MAX)
{<!-- -->
std::string timesFont("fonts/arial.ttf");
osgText::Text* text = new osgText::Text;
text->setCharacterSize(characterSize);
text->setText(message);
text->setFont(timesFont);
text->setAlignment(osgText::Text::CENTER_CENTER);
osg::Geode* geode = new osg::Geode;
geode->addDrawable(text);
geode->getOrCreateStateSet()->setMode(GL_LIGHTING, osg::StateAttribute::OFF);
osg::AutoTransform* at = new osg::AutoTransform;
at->addChild(geode);
at->setAutoRotateMode(osg::AutoTransform::ROTATE_TO_SCREEN);
at->setAutoScaleToScreen(true);
at->setMinimumScale(minScale);
at->setMaximumScale(maxScale);
at->setPosition(position);
return at;
}
osg::Node* createScene()
{<!-- -->
osg::Group* root = new osg::Group;
// int numReps = 3333;
int numReps = 10;
root->addChild(createAxis(osg::Vec3(0.0,0.0,0.0),osg::Vec3(1000.0,0.0,0.0),numReps,osg::AutoTransform::ROTATE_TO_CAMERA,osgText::Text::XY_PLANE, \ "ROTATE_TO_CAMERA"));
root->addChild(createAxis(osg::Vec3(0.0,0.0,0.0),osg::Vec3(0.0,1000.0,0.0),numReps,osg::AutoTransform::ROTATE_TO_SCREEN,osgText::Text::XY_PLANE, \ "ROTATE_TO_SCREEN"));
root->addChild(createAxis(osg::Vec3(0.0,0.0,0.0),osg::Vec3(0.0,0.0,1000.0),numReps,osg::AutoTransform::NO_ROTATION,osgText::Text::XZ_PLANE, \ "NO_ROTATION"));
root->addChild(createAutoScale(osg::Vec3(500.0,500.0,500.0), 25.0, "AutoScale with no min, max limits"));
root->addChild(createAutoScale(osg::Vec3(500.0,500.0,300.0), 25.0, "AutoScale with minScale = 1, maxScale = 2.0 ", 1, 2.0));
root->addChild(createAutoScale(osg::Vec3(500.0,500.0,700.0), 25.0, "AutoScale with minScale = 0.0, maxScale = 5.0 ", 0.0, 5.0));
return root;
}
osgViewer::View* createView(osg::ref_ptr<osg::Node> scenegraph, osg::ref_ptr<osg::GraphicsContext> gc, unsigned int x, unsigned int y, unsigned int width, unsigned int height)
{<!-- -->
OSG_NOTICE<<"createView(....,x="<<x<<", y="<<y<<", width="<<width<<", height= "<<height<<")"<<std::endl;
if (!gc)
{<!-- -->
osg::ref_ptr<osg::GraphicsContext::Traits> traits = new osg::GraphicsContext::Traits;
traits->x = x;
traits->y = y;
traits->width = width;
traits->height = height;
traits->windowDecoration = true;
traits->doubleBuffer = true;
traits->sharedContext = 0;
traits->readDISPLAY();
traits->setUndefinedScreenDetailsToDefaultScreen();
gc = osg::GraphicsContext::createGraphicsContext(traits.get());
if (!gc)
{<!-- -->
osg::notify(osg::NOTICE)<<" GraphicsWindow has not been created successfully."<<std::endl;
return 0;
}
x = 0;
y = 0;
}
osgViewer::View* view = new osgViewer::View;
view->getCamera()->setGraphicsContext(gc.get());
view->getCamera()->setViewport(new osg::Viewport(x, y, width, height));
//view->getCamera()->setProjectionMatrixAsPerspective(30.0, double(width) / double(height), 1.0, 1000.0);
view->setCameraManipulator(new osgGA::TrackballManipulator);
view->setSceneData(scenegraph);
return view;
}
int main(int argc, char** argv)
{<!-- -->
osg::ArgumentParser arguments( & amp;argc, argv);
// construct the viewer.
osgViewer::CompositeViewer viewer(arguments);
// create the scene graph that contains osg::AutoTransform nodes, see about for implementation details
osg::ref_ptr<osg::Node> scenegraph = createScene();
unsigned int numViews = 1;
while (arguments.read("-n",numViews)) {<!-- -->}
bool windows = false;
while (arguments.read("-w")) {<!-- --> windows = true; }
if (numViews<=1)
{<!-- -->
osgViewer::View* view = new osgViewer::View;
view->setUpViewAcrossAllScreens();
view->setSceneData(scenegraph.get());
view->setCameraManipulator(new osgGA::TrackballManipulator);
view->addEventHandler( new osgViewer::StatsHandler );
viewer.addView(view);
}
else
{<!-- -->
osg::GraphicsContext::WindowingSystemInterface* wsi = osg::GraphicsContext::getWindowingSystemInterface();
if (!wsi)
{<!-- -->
osg::notify(osg::NOTICE)<<"Error, no WindowSystemInterface available, cannot create windows."<<std::endl;
return 1;
}
unsigned int width, height;
osg::GraphicsContext::ScreenIdentifier main_screen_id;
main_screen_id.readDISPLAY();
main_screen_id.setUndefinedScreenDetailsToDefaultScreen();
wsi->getScreenResolution(main_screen_id, width, height);
unsigned int x=0, y=0;
while(arguments.read("--window", x, y, width, height)) {<!-- -->}
osg::ref_ptr<osg::GraphicsContext> gc;
if (!windows)
{<!-- -->
osg::ref_ptr<osg::GraphicsContext::Traits> traits = new osg::GraphicsContext::Traits;
traits->x = x;
traits->y = y;
traits->width = width;
traits->height = height;
traits->windowDecoration = true;
traits->doubleBuffer = true;
traits->sharedContext = 0;
traits->readDISPLAY();
traits->setUndefinedScreenDetailsToDefaultScreen();
gc = osg::GraphicsContext::createGraphicsContext(traits.get());
if (!gc)
{<!-- -->
osg::notify(osg::NOTICE)<<" GraphicsWindow has not been created successfully."<<std::endl;
return 1;
}
}
if (numViews==2)
{<!-- -->
viewer.addView(createView(scenegraph, gc, 0, 0, width/2, height));
viewer.addView(createView(scenegraph, gc, width/2, 0, width/2, height));
}
else if (numViews==3)
{<!-- -->
viewer.addView(createView(scenegraph, gc, 0, 0, width/2, height/2));
viewer.addView(createView(scenegraph, gc, width/2, 0, width/2, height/2));
viewer.addView(createView(scenegraph, gc, 0, height/2, width, height/2));
}
else
{<!-- -->
viewer.addView(createView(scenegraph, gc, 0, 0, width/2, height/2));
viewer.addView(createView(scenegraph, gc, width/2, 0, width/2, height/2));
viewer.addView(createView(scenegraph, gc, 0, height/2, width/2, height/2));
viewer.addView(createView(scenegraph, gc, width/2, height/2, width/2, height/2));
}
viewer.getView(0)->addEventHandler( new osgViewer::StatsHandler );
}
// run the viewers frame loop
return viewer.run();
}
Calling command: osgautotransform_d.exe -n 3
Running result: 
Calling command: osgautotransform_d.exe -n 4 -w
operation result:
