source: downloads/Samples/VolumeTex/src/VolumeTex.cpp @ 3

/*
-----------------------------------------------------------------------------
This source file is part of OGRE
    (Object-oriented Graphics Rendering Engine)
For the latest info, see http://www.ogre3d.org/

Copyright (c) 2000-2006 Torus Knot Software Ltd
Also see acknowledgements in Readme.html

You may use this sample code for anything you like, it is not covered by the
LGPL like the rest of the engine.
-----------------------------------------------------------------------------
*/
/**     Generate 3D julia sets and render them as volume texture
        This demonstrates
           - User generated textures
           - Procedural volume textures (Julia makes nice dust clouds)
           - Custom renderables
        @author W.J. van der Laan
*/

#include "ExampleApplication.h"
#include <OgreTexture.h>
#include <OgreHardwarePixelBuffer.h>
#include <OgreTextureManager.h>
#include <OgreLogManager.h>
#include <sstream>

#include "VolumeRenderable.h"
#include "ThingRenderable.h"
#include "Julia.h"

TexturePtr ptex;
SimpleRenderable *vrend;
SimpleRenderable *trend;
Overlay* overlay;
float xtime = 0.0f;
SceneNode *snode,*fnode;
AnimationState* mOgreAnimState = 0;

class VolumeTexFrameListener : public ExampleFrameListener
{
public:
        float global_real, global_imag, global_theta;
        
    VolumeTexFrameListener(RenderWindow* win, Camera* cam) : ExampleFrameListener( win, cam )
    {
                global_real = 0.4f;
                global_imag = 0.6f;
                global_theta = 0.0f;
                generate();
                
                updateInfoParamReal();
                updateInfoParamImag();
                updateInfoParamTheta();
    }
        
        void generate()
        {
                /* Evaluate julia fractal for each point */
                Julia julia(global_real, global_imag, global_theta);
                const float scale = 2.5;
                const float vcut = 29.0f;
                const float vscale = 1.0f/vcut;
                
                HardwarePixelBufferSharedPtr buffer = ptex->getBuffer(0, 0);
                std::stringstream d;
                d << "HardwarePixelBuffer " << buffer->getWidth() << " " << buffer->getHeight() << " " << buffer->getDepth();
                LogManager::getSingleton().logMessage(d.str());
                
                buffer->lock(HardwareBuffer::HBL_NORMAL);
                const PixelBox &pb = buffer->getCurrentLock();
                d.str("");
                d << "PixelBox " << pb.getWidth() << " " << pb.getHeight() << " " << pb.getDepth() << " " << pb.rowPitch << " " << pb.slicePitch << " " << pb.data << " " << PixelUtil::getFormatName(pb.format);
                LogManager::getSingleton().logMessage(d.str());
                
                uint32 *pbptr = static_cast<uint32*>(pb.data);
                for(size_t z=pb.front; z<pb.back; z++) 
        {
            for(size_t y=pb.top; y<pb.bottom; y++)
            {
                for(size_t x=pb.left; x<pb.right; x++)
                {
                    if(z==pb.front || z==(pb.back-1) || y==pb.top|| y==(pb.bottom-1) ||
                                                x==pb.left || x==(pb.right-1))
                                        {
                                                // On border, must be zero
                                                pbptr[x] = 0;
                    } 
                                        else
                                        {
                                                float val = julia.eval(((float)x/pb.getWidth()-0.5f) * scale, 
                                                                ((float)y/pb.getHeight()-0.5f) * scale, 
                                                                ((float)z/pb.getDepth()-0.5f) * scale);
                                                if(val > vcut)
                                                        val = vcut;
                                                
                                                PixelUtil::packColour((float)x/pb.getWidth(), (float)y/pb.getHeight(), (float)z/pb.getDepth(), (1.0f-(val*vscale))*0.7f, PF_A8R8G8B8, &pbptr[x]);
                                                
                                        }       
                }
                pbptr += pb.rowPitch;
            }
            pbptr += pb.getSliceSkip();
        }
                buffer->unlock();
        }
        void updateInfoParamReal()
        {
                OverlayManager::getSingleton().getOverlayElement("Example/VolTex/Param_real") \
                        ->setCaption("[1/2]real: "+StringConverter::toString(global_real));
        }
        void updateInfoParamImag()
        {
                OverlayManager::getSingleton().getOverlayElement("Example/VolTex/Param_imag") \
                        ->setCaption("[3/4]imag: "+StringConverter::toString(global_imag));
        }
        void updateInfoParamTheta()
        {
                OverlayManager::getSingleton().getOverlayElement("Example/VolTex/Param_theta") \
                        ->setCaption("[5/6]theta: "+StringConverter::toString(global_theta));
        }

    bool frameStarted( const FrameEvent& evt )
    {
        using namespace OIS;
        static float mTimeUntilNextToggle = 0.0f;
        if( ExampleFrameListener::frameStarted( evt ) == false )
                return false;
                
                mTimeUntilNextToggle -= evt.timeSinceLastFrame;
                
        if( (mKeyboard->isKeyDown( KC_1 ) || mKeyboard->isKeyDown( KC_2 )) 
                                && mTimeUntilNextToggle <= 0) {
                global_real += mKeyboard->isKeyDown( KC_1 )? -0.1f : 0.1f;
                        generate();
                        mTimeUntilNextToggle = 0.5;
                        updateInfoParamReal();
                }
                 if( (mKeyboard->isKeyDown( KC_3 ) || mKeyboard->isKeyDown( KC_4 )) 
                                && mTimeUntilNextToggle <= 0) {
                global_imag += mKeyboard->isKeyDown( KC_3 )? -0.1f : 0.1f;
                        generate();
                        mTimeUntilNextToggle = 0.5;
                        updateInfoParamImag();
                }
                if( (mKeyboard->isKeyDown( KC_5 ) || mKeyboard->isKeyDown( KC_6 )) 
                                && mTimeUntilNextToggle <= 0) {
                global_theta += mKeyboard->isKeyDown( KC_5 )? -0.1f : 0.1f;
                        generate();
                        mTimeUntilNextToggle = 0.5;
                        updateInfoParamTheta();
                }
                
                xtime += evt.timeSinceLastFrame;
                xtime = fmod(xtime, 10.0f);
                //snode->roll(Degree(evt.timeSinceLastFrame * 20.0f));
                //fnode->roll(Degree(evt.timeSinceLastFrame * 20.0f));
                static_cast<ThingRenderable*>(trend)->addTime(evt.timeSinceLastFrame * 0.05f);
                mOgreAnimState->addTime(evt.timeSinceLastFrame);
        return true;
    }
        ~VolumeTexFrameListener()
        {
                delete vrend;
                delete trend;
        }
};



class VolumeTexApplication : public ExampleApplication
{
public:
    VolumeTexApplication() {}


protected:
        
    virtual void createFrameListener(void)
    {
        mFrameListener= new VolumeTexFrameListener(mWindow, mCamera);
        mFrameListener->showDebugOverlay(true);
        mRoot->addFrameListener(mFrameListener);
    }


        virtual void createViewports(void)
    {
                // Create one viewport, entire window
        Viewport* vp = mWindow->addViewport(mCamera);
        vp->setBackgroundColour(ColourValue(0,0,0));

        // Alter the camera aspect ratio to match the viewport
        mCamera->setAspectRatio( 
            Real(vp->getActualWidth()) / Real(vp->getActualHeight()));
    }
        void createCamera(void)
        {
                // Create the camera
        mCamera = mSceneMgr->createCamera("PlayerCam");
        mCamera->setPosition(Vector3(220,-2,176));
        mCamera->lookAt(Vector3(0,0,0));
        mCamera->setNearClipDistance(5);
                mCamera->setFixedYawAxis(false);
        }
    // Just override the mandatory create scene method
    void createScene(void)
    {
                // Check capabilities
        /*
                const RenderSystemCapabilities* caps = Root::getSingleton().getRenderSystem()->getCapabilities();
        if (!caps->hasCapability(RSC_TEXTURE_3D))
        {
            OGRE_EXCEPT(Exception::ERR_NOT_IMPLEMENTED, "Your card does not support 3D textures, so cannot "
                "run this demo. Sorry!", 
                "VolTex::createScene");
        }
        */
                
        // Create dynamic texture
                ptex = TextureManager::getSingleton().createManual(
                        "DynaTex","General", TEX_TYPE_3D, 64, 64, 64, 0, PF_A8R8G8B8);
                


                // Set ambient light
        mSceneMgr->setAmbientLight(ColourValue(0.6, 0.6, 0.6));
                mSceneMgr->setSkyBox(true, "Examples/MorningSkyBox", 50 );

        //mRoot->getRenderSystem()->clearFrameBuffer(FBT_COLOUR, ColourValue(255,255,255,0));

        // Create a light
        Light* l = mSceneMgr->createLight("MainLight");
        l->setDiffuseColour(0.75, 0.75, 0.80);
                l->setSpecularColour(0.9, 0.9, 1);
        l->setPosition(-100,80,50);
                mSceneMgr->getRootSceneNode()->attachObject(l);

                // Create manual material
                
                
                // Create volume renderable
                snode = mSceneMgr->getRootSceneNode()->createChildSceneNode(Vector3(0,0,0));      
                
        vrend = new VolumeRenderable(32, 750.0f, "DynaTex");
        snode->attachObject( vrend );
                
                trend = new ThingRenderable(90.0f, 32, 7.5f);
                trend->setMaterial("Examples/VTDarkStuff");
                snode->attachObject(trend);
                
                // Ogre head node
                fnode = mSceneMgr->getRootSceneNode()->createChildSceneNode(Vector3(0,0,0));
                // Load ogre head
                Entity* head = mSceneMgr->createEntity("head", "ogrehead.mesh");
                fnode->attachObject(head);
                
                // Animation for ogre head
                // Create a track for the light
        Animation* anim = mSceneMgr->createAnimation("OgreTrack", 10);
        // Spline it for nice curves
        anim->setInterpolationMode(Animation::IM_SPLINE);
        // Create a track to animate the camera's node
        NodeAnimationTrack* track = anim->createNodeTrack(0, fnode);
        // Setup keyframes
        TransformKeyFrame* key = track->createNodeKeyFrame(0); // A startposition
        key->setTranslate(Vector3(0.0f, -15.0f, 0.0f));
        key = track->createNodeKeyFrame(5);//B
        key->setTranslate(Vector3(0.0f, 15.0f, 0.0f));
        key = track->createNodeKeyFrame(10);//C
        key->setTranslate(Vector3(0.0f, -15.0f, 0.0f));
        // Create a new animation state to track this
        mOgreAnimState = mSceneMgr->createAnimationState("OgreTrack");
        mOgreAnimState->setEnabled(true);
     
        //mFountainNode->attachObject(pSys2);
                // show GUI
                overlay = OverlayManager::getSingleton().getByName("Example/VolTexOverlay");    
                overlay->show();
    }

        void destroyScene()
        {
                ptex.setNull();
        }

};

#if OGRE_PLATFORM == OGRE_PLATFORM_WIN32
#define WIN32_LEAN_AND_MEAN
#include "windows.h"
#endif

#ifdef __cplusplus
extern "C" {
#endif

#if OGRE_PLATFORM == OGRE_PLATFORM_WIN32
INT WINAPI WinMain( HINSTANCE hInst, HINSTANCE, LPSTR strCmdLine, INT )
#else
int main(int argc, char *argv[])
#endif
{
    // Create application object
    VolumeTexApplication app;

    try {
        app.go();
    } catch( Ogre::Exception& e ) {
#if OGRE_PLATFORM == OGRE_PLATFORM_WIN32
        MessageBox( NULL, e.getFullDescription().c_str(), "An exception has occured!", MB_OK | MB_ICONERROR | MB_TASKMODAL);
#else
        std::cerr << "An exception has occured: " <<
            e.getFullDescription().c_str() << std::endl;
#endif
    }

    return 0;
}

#ifdef __cplusplus
}
#endif