// Initialize GLUT & OpenSG and set up the scene
int main(int argc, char **argv)
{
// OSG init
OSG::osgInit(argc,argv);
// GLUT init
int winid = setupGLUT(&argc, argv);
// open a new scope, because the pointers below should go out of scope
// before entering glutMainLoop.
// Otherwise OpenSG will complain about objects being alive after shutdown.
{
// the connection between GLUT and OpenSG
OSG::GLUTWindowRefPtr gwin = OSG::GLUTWindow::create();
gwin->setGlutId(winid);
gwin->init();
// The scene group
OSG::NodeRefPtr scene = OSG::Node::create();
OSG::GroupRefPtr g = OSG::Group::create();
scene->setCore(g);
if(argc < 2)
{
FWARNING(("No file given!\n"));
FWARNING(("Supported file formats:\n"));
std::list<const char*> suffixes;
OSG::SceneFileHandler::the()->getSuffixList(suffixes);
for(std::list<const char*>::iterator it = suffixes.begin();
it != suffixes.end();
++it)
{
FWARNING(("%s\n", *it));
}
fileroot = OSG::makeTorus(.5, 2, 16, 16);
}
else
{
fileroot = OSG::SceneFileHandler::the()->read(argv[1]);
/*
All scene file loading is handled via the SceneFileHandler.
*/
}
scene->addChild(fileroot);
// Create a small geometry to show the ray and what was hit
// Contains a line and a single triangle.
// The line shows the ray, the triangle whatever was hit.
OSG::SimpleMaterialRefPtr red = OSG::SimpleMaterial::create();
red->setDiffuse (OSG::Color3f( 1,0,0 ));
red->setTransparency(0.5);
red->setLit (false);
isectPoints = OSG::GeoPnt3fProperty::create();
isectPoints->addValue(OSG::Pnt3f(0,0,0));
isectPoints->addValue(OSG::Pnt3f(0,0,0));
isectPoints->addValue(OSG::Pnt3f(0,0,0));
isectPoints->addValue(OSG::Pnt3f(0,0,0));
isectPoints->addValue(OSG::Pnt3f(0,0,0));
OSG::GeoUInt32PropertyRefPtr index = OSG::GeoUInt32Property::create();
index->addValue(0);
index->addValue(1);
index->addValue(2);
index->addValue(3);
index->addValue(4);
OSG::GeoUInt32PropertyRefPtr lens = OSG::GeoUInt32Property::create();
lens->addValue(2);
lens->addValue(3);
OSG::GeoUInt8PropertyRefPtr type = OSG::GeoUInt8Property::create();
type->addValue(GL_LINES);
type->addValue(GL_TRIANGLES);
testgeocore = OSG::Geometry::create();
testgeocore->setPositions(isectPoints);
testgeocore->setIndices(index);
testgeocore->setLengths(lens);
testgeocore->setTypes(type);
testgeocore->setMaterial(red);
OSG::NodeRefPtr testgeo = OSG::Node::create();
testgeo->setCore(testgeocore);
scene->addChild(testgeo);
// create the SimpleSceneManager helper
mgr = OSG::SimpleSceneManager::create();
// tell the manager what to manage
mgr->setWindow(gwin );
mgr->setRoot (scene);
// show the whole scene
mgr->showAll();
mgr->getCamera()->setNear(mgr->getCamera()->getNear() / 10);
// Show the bounding volumes? Not for now
mgr->getRenderAction()->setVolumeDrawing(false);
_idbuff = new IDbuffer();
_idbuff->setCamera(mgr->getCamera());
_idbuff->setRoot(scene);
}
// GLUT main loop
glutMainLoop();
return 0;
}
// Initialize GLUT & OpenSG and set up the scene
int main(int argc, char **argv)
{
// OSG init
OSG::osgInit(argc,argv);
// GLUT init
int winid = setupGLUT(&argc, argv);
// Args given?
if(argc > 1)
{
if(sscanf(argv[1], "%u", &nlights) != 1)
{
FWARNING(("Number of lights '%s' not understood.\n", argv[1]));
nlights = 3;
}
}
// open a new scope, because the pointers below should go out of scope
// before entering glutMainLoop.
// Otherwise OpenSG will complain about objects being alive after shutdown.
{
// the connection between GLUT and OpenSG
OSG::GLUTWindowRefPtr gwin = OSG::GLUTWindow::create();
gwin->setGlutId(winid);
gwin->init();
/*
A Light defines a source of light in the scene. Generally, two types
of information are of interest: The position of the light source
(geometry), and what elements of the scene are lit (semantics).
Using the position of the light in the graph for geometry allows
moving the Light just like any other node, by putting it below a
OSG::Transform Node and changing the transformation. This consistency
also simplifies attaching Lights to moving parts in the scene: just
put them below the same Transform and they will move with the object.
The semantic interpretation also makes sense, it lets you restrict the
influence area of the light to a subgraph of the scene. This can be
used for efficiency, as every active light increases the amount of
calculations necessary per vertex, even if the light doesn't influence
the vertex, because it is too far away. It can also be used to
overcome the restrictions on the number of lights. OpenSG currently
only allows 8 concurrently active lights.
It is also not difficult to imagine situations where both
interpretations are necessary at the same time. Take for example a car
driving through a night scene. You'd want to headlights to be fixed to
the car and move together with it. But at the same time they should
light the houses you're driving by, and not the mountains in the
distance.
Thus there should be a way to do both at the same time. OpenSG solves
this by splitting the two tasks to two Nodes. The Light's Node is for
the sematntic part, it defines which object are lit by the Light. FOr
the geometrc part the Light keeps a SFNodePtr to a different Node, the
so called beacon. The local coordinate system of the beacon provides
the reference coordinate system for the light's position.
Thus the typical setup of an OpenSG scenegraph starts with a set of
lights, which light the whole scene, followed by the actual geometry.
Tip: Using the beacon of the camera (see \ref PageSystemWindowCamera)
as the beacon of a light source creates a headlight.
Every light is closely related to OpenGL's light specification. It has
a diffuse, specular and ambient color. Additionally it can be switched
on and off using the on field.
*/
// Create the scene
OSG::NodeRefPtr scene = OSG::Node::create();
OSG::GroupRefPtr group = OSG::Group::create();
scene->setCore(group);
// create the scene to be lit
// a simple torus is fine for now.
// You can add more Geometry here if you want to.
OSG::NodeRefPtr lit_scene = OSG::makeTorus(.5, 2, 32, 64);
// helper node to keep the lights on top of each other
OSG::NodeRefPtr lastnode = lit_scene;
// create the light sources
OSG::Color3f colors[] =
{
OSG::Color3f(1,0,0), OSG::Color3f(0,1,0), OSG::Color3f(0,0,1),
OSG::Color3f(1,1,0), OSG::Color3f(0,1,1), OSG::Color3f(1,0,1),
OSG::Color3f(1,1,1), OSG::Color3f(1,1,1)
};
if(nlights > 8)
{
FWARNING(("Currently only 8 lights supported\n"));
nlights = 8;
}
// scale the lights to not overexpose everything. Just a little.
OSG::Real32 scale = OSG::osgMax(1., 1.5 / nlights);
for(OSG::UInt16 i = 0; i < nlights; ++i)
{
// create the light source
OSG::NodeRefPtr light = OSG::Node::create();
OSG::LightRefPtr light_core;
OSG::NodeRefPtr geo_node;
switch((i % 3) + 0)
{
/*
The PointLight has a position to define its location. In
addition, as it really is located in the scene, it has
attenuation parameters to change the light's intensity
depending on the distance to the light.
Point lights are more expesinve to compute than directional
lights, but not quite as expesive as spot lights. If you need
to see the localized effects of the light, a point light is a
good compromise between speed and quality.
*/
case 0:
{
OSG::PointLightRefPtr l = OSG::PointLight::create();
l->setPosition (0, 0, 0);
l->setConstantAttenuation (1);
l->setLinearAttenuation (0);
l->setQuadraticAttenuation (3);
// a little sphere to show where the light is
geo_node = OSG::makeLatLongSphere(8, 8, 0.1f);
OSG::GeometryRefPtr geo =
dynamic_cast<OSG::Geometry *>(geo_node->getCore());
OSG::SimpleMaterialRefPtr sm =
OSG::SimpleMaterial::create();
sm->setLit(false);
sm->setDiffuse(OSG::Color3f( colors[i][0],
colors[i][1],
colors[i][2] ));
geo->setMaterial(sm);
light_core = l;
}
break;
/*
The DirectionalLight just has a direction.
To use it as a headlight use (0,0,-1) as a direction. it is
the computationally cheapest light source. Thus for the
fastest lit rendering, just a single directional light source.
The osg::SimpleSceneManager's headlight is a directional light
source.
*/
case 1:
{
OSG::DirectionalLightRefPtr l =
OSG::DirectionalLight::create();
l->setDirection(0, 0, 1);
// a little cylinder to show where the light is
geo_node = OSG::makeCylinder(.1f, .03f, 8, true, true, true);
OSG::GeometryRefPtr geo =
dynamic_cast<OSG::Geometry *>(geo_node->getCore());
OSG::SimpleMaterialRefPtr sm =
OSG::SimpleMaterial::create();
sm->setLit(false);
sm->setDiffuse(OSG::Color3f( colors[i][0],
colors[i][1],
colors[i][2] ));
geo->setMaterial(sm);
light_core = l;
}
break;
/*
The SpotLight adds a direction to the PointLight and a
spotCutOff angle to define the area that's lit. To define the
light intensity fallof within that area the spotExponent field
is used.
Spot lights are very expensive to compute, use them sparingly.
*/
case 2:
{
OSG::SpotLightRefPtr l = OSG::SpotLight::create();
l->setPosition (OSG::Pnt3f(0, 0, 0));
l->setDirection (OSG::Vec3f(0, -1, 0));
l->setSpotExponent (2);
l->setSpotCutOff (OSG::osgDegree2Rad(45));
l->setConstantAttenuation (1);
l->setLinearAttenuation (0);
l->setQuadraticAttenuation (3);
// a little cone to show where the light is
geo_node = OSG::makeCone(.2f, .2f, 8, true, true);
OSG::GeometryRefPtr geo =
dynamic_cast<OSG::Geometry *>(geo_node->getCore());
OSG::SimpleMaterialRefPtr sm =
OSG::SimpleMaterial::create();
sm->setLit(false);
sm->setDiffuse(OSG::Color3f( colors[i][0],
colors[i][1],
colors[i][2] ));
geo->setMaterial(sm);
light_core = l;
}
break;
}
// create the beacon and attach it to the scene
OSG::NodeRefPtr beacon = OSG::Node::create();
OSG::TransformRefPtr beacon_core = OSG::Transform::create();
lightBeacons[i] = beacon_core;
beacon->setCore(beacon_core);
beacon->addChild(geo_node);
scene->addChild(beacon);
light_core->setAmbient (colors[i][0] / scale,
colors[i][1] / scale,
colors[i][2] / scale,
1);
light_core->setDiffuse (colors[i][0] / scale,
colors[i][1] / scale,
colors[i][2] / scale,
1);
light_core->setSpecular(1 / scale,
1 / scale,
1 / scale,
1);
light_core->setBeacon (beacon);
light->setCore(light_core);
light->addChild(lastnode);
lights[i] = light_core;
lastnode = light;
}
scene->addChild(lastnode);
OSG::commitChanges();
// create the SimpleSceneManager helper
mgr = OSG::SimpleSceneManager::create();
// tell the manager what to manage
mgr->setWindow(gwin );
mgr->setRoot (scene);
// switch the headlight off, we have enough lights as is
mgr->setHeadlight(false);
// show the whole scene
mgr->showAll();
}
// GLUT main loop
glutMainLoop();
return 0;
}