I've done this in raw
OpenGL before, but I can't for the life of me get
it working in
OpenSceneGraph. I need to render a scene and then display
the result
in 2 separate windows: One showing the Color Buffer, one
SHowing the
Depth Buffer (and eventually a 3rd showing the STencil
Buffer).
I've tried all day and got varying results, but nothing
approaching
success. CAn someone tell me what I'm doing wrong?
Relevant code
below.. Don't laugh too hard, I've been googling and
reading the
examples and cut-n-pasting code snippets all day, and I'm
relatively
sure that at least 50% of this is unnecessary.. Right now
it's in a
state of opening my windows & showing _a_ texture, but it's
all
black (except for the red border I allowed just to see if this code
is
doing anything at all). The closest I got was using about 4 cameras
(a
Main camera, a Depth FBO camera, then 2 separate cameras for the 2
final
screen-aligned quads), which would render my geometry on screen
but
nothing into the Depth or Color buffer textures.
.....
Initialization stuff up here, nothing to do with OpenSceneGraph ...
there's
a global global osgViewer::CompositeViewer "compViewer"
viewerColor = new osgViewer::View();
viewerDepth = new
osgViewer::View();
{
std::cout << "**
Initializing depth & color texture " << std::endl;
// Now setup the Depth Texture
__depthTexture = new
osg::Texture2D();
__depthTexture->setTextureSize(width,
height);
__depthTexture->setInternalFormat(GL_DEPTH_COMPONENT);
__depthTexture->setFilter(osg::Texture2D::MIN_FILTER,osg::Texture2D::LINEAR);
__depthTexture->setFilter(osg::Texture2D::MAG_FILTER,osg::Texture2D::LINEAR);
__colorTexture = new osg::Texture2D();
__colorTexture->setTextureSize(width, height);
__colorTexture->setInternalFormat(GL_RGBA);
__colorTexture->setFilter(osg::Texture2D::MIN_FILTER,osg::Texture2D::LINEAR);
__colorTexture->setFilter(osg::Texture2D::MAG_FILTER,osg::Texture2D::LINEAR);
osg::ref_ptr<osg::GraphicsContext::Traits> traits = new
osg::GraphicsContext::Traits;
traits->x = xPos + 0;
traits->y = yPos + 0;
traits->width = width;
traits->height = height;
traits->windowDecoration = true;
traits->doubleBuffer = true;
traits->sharedContext = 0;
traits->vsync = false;
osg::ref_ptr<osg::GraphicsContext> gc =
osg::GraphicsContext::createGraphicsContext(traits.get());
std::cout << "** Initializing prime camera" <<
std::endl;
__camera = new osg::Camera();
__camera->setGraphicsContext(gc.get());
__camera->setViewport(new osg::Viewport(0,0, traits->width,
traits->height));
__camera->setComputeNearFarMode(osg::Camera::DO_NOT_COMPUTE_NEAR_FAR);
__camera->setProjectionMatrixAsPerspective(70,1.0, 1,200);
__camera->setClearDepth(1.0);
__camera->setViewMatrixAsLookAt( osg::Vec3(0,0,0),
osg::Vec3(0,100,0),
osg::Vec3(0,0,1) );
GLenum buffer = traits->doubleBuffer ?
GL_BACK : GL_FRONT;
__camera->setDrawBuffer(buffer);
__camera->setReadBuffer(buffer);
__camera->getOrCreateStateSet()->setRenderBinDetails(50,"RenderBin");
//__camera->setRenderOrder(osg::Camera::NESTED_RENDER);
__camera->setRenderOrder(osg::Camera::PRE_RENDER);
__camera->setRenderTargetImplementation(osg::Camera::FRAME_BUFFER_OBJECT);
__camera->attach(osg::Camera::DEPTH_BUFFER, __depthTexture);
__camera->attach(osg::Camera::COLOR_BUFFER, __colorTexture);
std::cout << "** Attaching cmaeras to viewer " <<
std::endl;
// add this slave camera to the viewer, with a
shift left of the
projection matrix
if (__Side ==
"leftview") {
//viewerColor->addSlave(__depthCamera,
osg::Matrixd::translate(-0.8,0,0),
osg::Matrixd());
viewerColor->addSlave(__camera.get(),
osg::Matrixd::translate(-0.8,0,0),
osg::Matrixd());
} else if (__Side == "rightview") {
//viewerColor->addSlave(__depthCamera,
osg::Matrixd::translate(+0.8,0,0),
osg::Matrixd());
viewerColor->addSlave(__camera.get(),
osg::Matrixd::translate(0.8,0,0),
osg::Matrixd());
} else {
//viewerColor->addSlave(__depthCamera, osg::Matrixd(),
osg::Matrixd(),false);
viewerColor->addSlave(__camera.get(), osg::Matrixd(),
osg::Matrixd());
}
std::cout << " Planar Depth " <<
std::endl;
osg::Camera* camPtr = PlanarQuad(xPos, yPos,
width,height, gc,
true, buffer,__depthTexture);
viewerDepth->addSlave(camPtr, osg::Matrixd(), osg::Matrixd(),
false);
std::cout << " Planar color " << std::endl;
camPtr = PlanarQuad(xPos, yPos, width,height, gc,
false,buffer,__colorTexture);
viewerColor->addSlave(camPtr, osg::Matrixd(), osg::Matrixd(),
false);
}
std::cout << "** Initializing viewerColor " <<
std::endl;
// Initialize the variables we'll need for this
compViewer->addView(viewerColor);
compViewer->addView(viewerDepth);
viewerColor->setCameraManipulator(new osgGA::TrackballManipulator());
viewerColor->home();
std::cout << "**
Initializing viewerDepth " << std::endl;
viewerDepth->setCameraManipulator(new osgGA::TrackballManipulator());
viewerDepth->assignSceneDataToCameras();
viewerDepth->home();
// This is required or the
viewer.frame() doesn't work for some reason
// TODO: Write our
own "Null" manipulator
_frameCount = 0;
return 1;
}
osg::Camera*
osgRenderer::PlanarQuad( int xPos, int yPos, int width, int
height,
osg::GraphicsContext *gc,
bool newGC, GLenum buffer,
osg::Texture2D *tex) {
// Build a quad to simply display the
Depth Buffer texture
// Construct a Geode, and assign the Quad to
it
// and assign the texture
// Also set it to ignore
Depth Test, since it will be background
// Debug: Leave a 10px
border to see the scene behind
osg::ref_ptr<osg::Drawable> quad =
osg::createTexturedQuadGeometry(
osg::Vec3(10,10.0,0),
osg::Vec3(width-20,0,0),osg::Vec3(0,height-20,0),
0, 1, 0, 1);
quad->getOrCreateStateSet()->setTextureAttributeAndModes(0, tex);
quad->setDataVariance( osg::Object::STATIC );
quad->setUseDisplayList( true );
quad->getOrCreateStateSet()->setMode(GL_DEPTH_TEST,osg::StateAttribute::OFF);
osg::ref_ptr<osg::Geode> geode = new osg::Geode;
geode->addDrawable( quad.get() );
geode->getOrCreateStateSet()->setTextureAttributeAndModes(0, tex,
osg::StateAttribute::ON);
geode->getOrCreateStateSet()->setTextureMode(0,
GL_TEXTURE_2D,osg::StateAttribute::ON);
geode->getOrCreateStateSet()->setMode(GL_DEPTH_TEST,osg::StateAttribute::OFF);
osg::ref_ptr<osg::Camera> depCam = new osg::Camera();
// set the projection matrix
depCam->setProjectionMatrix(osg::Matrix::ortho2D(0,width,0,height));
// set the view matrix
depCam->setReferenceFrame(osg::Transform::ABSOLUTE_RF);
depCam->setViewMatrix(osg::Matrix::identity());
// No need to
clear anything honestly
depCam->setClearMask(NULL);
//depCam->setRenderOrder(osg::Camera::POST_RENDER);
//depCam->getOrCreateStateSet()->setMode(GL_LIGHTING,
osg::StateAttribute::OFF);
depCam->addChild(geode.get());
std::cout << "**
Initializing viewerDepth camera" << std::endl;
osg::Camera*
depCamSlave = new osg::Camera();
depCamSlave->setClearMask(GL_DEPTH_BUFFER_BIT | GL_COLOR_BUFFER_BIT);
if (newGC) {
std::cout << "** Initializing depth
traits" << std::endl;
osg::ref_ptr<osg::GraphicsContext::Traits> depTraits = new
osg::GraphicsContext::Traits;
depTraits->x = xPos + 0;
depTraits->y = yPos +
height;
depTraits->width = width;
depTraits->height = height;
depTraits->windowDecoration
= true;
depTraits->doubleBuffer = true;
depTraits->sharedContext = gc;
depTraits->vsync =
false;
osg::ref_ptr<osg::GraphicsContext> dep_gc =
osg::GraphicsContext::createGraphicsContext(depTraits.get());
depCamSlave->setGraphicsContext(dep_gc.get());
depCamSlave->setDrawBuffer(buffer);
depCamSlave->setReadBuffer(buffer);
} else {
depCamSlave->setGraphicsContext(gc);
}
depCamSlave->setViewport(0,0,width,height);
depCamSlave->setAllowEventFocus(false);
depCamSlave->setRenderOrder(osg::Camera::POST_RENDER);
depCamSlave->setClearColor(osg::Vec4(1.0f,0.0f,0.0f,0.0f));
depCamSlave->setClearDepth(1.0);
depCamSlave->getOrCreateStateSet()->setMode(GL_LIGHTING,osg::StateAttribute::OFF);
depCamSlave->getOrCreateStateSet()->setMode(GL_BLEND,osg::StateAttribute::OFF);
depCamSlave->getOrCreateStateSet()->setMode(GL_DEPTH_TEST,osg::StateAttribute::OFF);
osg::TexEnv* pTexEnv = new osg::TexEnv();
pTexEnv->setMode(osg::TexEnv::REPLACE);
depCamSlave->getOrCreateStateSet()->setTextureAttributeAndModes(0,
pTexEnv,
osg::StateAttribute::ON);
depCamSlave->addChild(depCam.get());
std::cout <<
"returning" << std::endl;
return depCamSlave;
}
and
later in the code I call :
void
osgRenderer::RegisterWithScene(osg::Group* _root) {
viewerColor->setSceneData(_root);
viewerColor->assignSceneDataToCameras();
}
