OpenSceneGraph/examples/osgoit/osgoit.cpp
Robert Osfield 6a67be2e32 Introduced CMake option OSG_PROVIDE_READFILE option that defaults to ON, but when switched to OFF disables the building of the osgDB::read*File() methods,
forcing users to use osgDB::readRef*File() methods.  The later is preferable as it closes a potential threading bug when using paging databases in conjunction
with the osgDB::Registry Object Cache.  This threading bug occurs when one thread gets an object from the Cache via an osgDB::read*File() call where only
a pointer to the object is passed back, so taking a reference to the object is delayed till it gets reassigned to a ref_ptr<>, but at the same time another
thread calls a flush of the Object Cache deleting this object as it's referenceCount is now zero.  Using osgDB::readREf*File() makes sure the a ref_ptr<> is
passed back and the referenceCount never goes to zero.

To ensure the OSG builds when OSG_PROVIDE_READFILE is to OFF the many cases of osgDB::read*File() usage had to be replaced with a ref_ptr<> osgDB::readRef*File()
usage.  The avoid this change causing lots of other client code to be rewritten to handle the use of ref_ptr<> in place of C pointer I introduced a serious of
templte methods in various class to adapt ref_ptr<> to the underly C pointer to be passed to old OSG API's, example of this is found in include/osg/Group:

    bool addChild(Node* child); // old method which can only be used with a Node*

    tempalte<class T> bool addChild(const osg::ref_ptr<T>& child) { return addChild(child.get()); } // adapter template method

These changes together cover 149 modified files, so it's a large submission. This extent of changes are warrent to make use of the Object Cache
and multi-threaded loaded more robust.



git-svn-id: http://svn.openscenegraph.org/osg/OpenSceneGraph/branches/OpenSceneGraph-3.4@15165 16af8721-9629-0410-8352-f15c8da7e697
2015-10-22 14:14:53 +00:00

127 lines
5.8 KiB
C++

/* OpenSceneGraph example, myosgoit.
*
* Author: Christian Buchner, based on original osgoit by Mathias Frhlich
*
* This demo provides a DepthPeeling object that can correctly compose
* solid and transparent geometry within the same scene. The transparent
* geometry can also use GLSL shaders, as demonstrated in the 3D HeatMap.
* The solid geometry is only rendered once, and its depth buffer blitted
* into the cameras rendering the transparency layers.
*
* Permission is hereby granted, free of charge, to any person obtaining a copy
* of this software and associated documentation files (the "Software"), to deal
* in the Software without restriction, including without limitation the rights
* to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
* copies of the Software, and to permit persons to whom the Software is
* furnished to do so, subject to the following conditions:
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
* AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
* OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
* THE SOFTWARE.
*/
#include "DepthPeeling.h"
#include "HeatMap.h"
#include <osgViewer/Viewer>
#include <osgViewer/ViewerEventHandlers>
#include <osg/Math>
#include <osg/PositionAttitudeTransform>
#include <osg/BlendFunc>
#include <osg/Material>
#include <osg/LightModel>
#include <osgDB/ReadFile>
#include <limits>
#include <iostream>
int main(int argc, char** argv)
{
// use an ArgumentParser object to manage the program arguments.
osg::ArgumentParser arguments(&argc, argv);
arguments.getApplicationUsage()->addKeyboardMouseBinding("m", "Increase the number of depth peeling layers");
arguments.getApplicationUsage()->addKeyboardMouseBinding("n", "Decrease the number of depth peeling layers");
arguments.getApplicationUsage()->addKeyboardMouseBinding("l", "Toggle display of the individual or composed layer textures");
arguments.getApplicationUsage()->addKeyboardMouseBinding("p", "Increase the layer offset");
arguments.getApplicationUsage()->addKeyboardMouseBinding("o", "Decrease the layer offset");
// Have the usual viewer
osgViewer::Viewer viewer(arguments);
osg::DisplaySettings* displaySettings = new osg::DisplaySettings;
viewer.setDisplaySettings(displaySettings);
// Add the stats handler
viewer.addEventHandler(new osgViewer::StatsHandler);
// add the help handler
viewer.addEventHandler(new osgViewer::HelpHandler(arguments.getApplicationUsage()));
// any option left unread are converted into errors to write out later.
arguments.reportRemainingOptionsAsUnrecognized();
// read the dump truck, we will need it twice
osg::ref_ptr<osg::Node> dt = osgDB::readRefNodeFile("dumptruck.osg");
// display a solid version of the dump truck
osg::ref_ptr<osg::PositionAttitudeTransform> solidModel = new osg::PositionAttitudeTransform;
solidModel->setPosition(osg::Vec3f(7.0f, -2.0f, 7.0f));
solidModel->addChild(dt);
// generate the 3D heatmap surface to display
osg::ref_ptr<Heatmap> hm = new Heatmap(30, 30, 10, 30, 30, 1.0, 0.25);
float data[30][30];
for (int x=0; x < 30; ++x)
for (int y=0; y < 30; ++y)
data[y][x] = (double)rand() / RAND_MAX;
hm->setData((float*)data, 10.0, 1.0, 0.25);
// add a transparent version of the truck to the scene also
osg::ref_ptr<osg::PositionAttitudeTransform> transparentTruck = new osg::PositionAttitudeTransform;
transparentTruck->setPosition(osg::Vec3f(7.0f, -25.0f, 7.0f));
// set the states of the truck so that it actually appears transparently and nicely lit.
osg::StateSet *state = transparentTruck->getOrCreateStateSet();
state->setMode(GL_BLEND, osg::StateAttribute::ON | osg::StateAttribute::OVERRIDE);
state->setAttribute(new osg::BlendFunc(GL_SRC_ALPHA, GL_ONE_MINUS_SRC_ALPHA), osg::StateAttribute::ON | osg::StateAttribute::OVERRIDE);
osg::Material* material = new osg::Material;
material->setAmbient(osg::Material::FRONT_AND_BACK,osg::Vec4(0.2f,0.2f,0.2f,0.3f));
material->setDiffuse(osg::Material::FRONT_AND_BACK,osg::Vec4(0.8f,0.8f,0.8f,0.3f));
state->setAttribute(material,osg::StateAttribute::ON | osg::StateAttribute::OVERRIDE);
osg::LightModel *lm = new osg::LightModel();
lm->setTwoSided(true);
state->setAttribute(lm, osg::StateAttribute::ON | osg::StateAttribute::OVERRIDE);
(transparentTruck.get())->addChild(dt.get());
// place the heatmap and a transparent dump truck in the transparent geometry group
osg::ref_ptr<osg::Group> transparentModel = new osg::Group;
(transparentModel.get())->addChild(hm.get());
(transparentModel.get())->addChild(transparentTruck.get());
// The initial size set to 0, 0. We get a resize event for the right size...
DepthPeeling* depthPeeling = new DepthPeeling(0, 0);
// the heat map already uses two textures bound to unit 0 and 1, so we can use TexUnit 2 for the peeling
depthPeeling->setTexUnit(2);
depthPeeling->setSolidScene(solidModel.get());
depthPeeling->setTransparentScene(transparentModel.get());
viewer.setSceneData(depthPeeling->getRoot());
// Add the event handler for the depth peeling stuff
viewer.addEventHandler(new DepthPeeling::EventHandler(depthPeeling));
// force a resize event, so the DepthPeeling object updates _texWidth and _texHeight
viewer.realize();
int x, y, width, height;
osgViewer::ViewerBase::Windows windows;
viewer.getWindows(windows);
windows.front()->getWindowRectangle(x,y,width,height);
viewer.getEventQueue()->windowResize(x,y,width,height);
return viewer.run();
}