source: GTP/trunk/App/Demos/Vis/CHC_revisited/chcdemo.cpp @ 2763

// occquery.cpp : Defines the entry point for the console application.
//
#include <math.h>
#include <time.h>
#include "common.h"
#include "glInterface.h"
#include "RenderTraverser.h"
#include "SceneEntity.h"
#include "Vector3.h"
#include "Matrix4x4.h"
#include "BinaryLoader.h"
#include "Bvh.h"
#include "Camera.h"
#include "Geometry.h"
#include "BvhLoader.h"
#include "FrustumCullingTraverser.h"
#include "StopAndWaitTraverser.h"



using namespace std;
using namespace CHCDemo;



/// the renderable scene geometry
SceneEntityContainer sceneEntities;
// traverses and renders the hierarchy
RenderTraverser *traverser;
/// the hierarchy
Bvh *bvh;
/// the scene camera
Camera *camera;
/// the scene bounding box
AxisAlignedBox3 sceneBox;
/// the current render state
RenderState state;

// eye near plane distance
float nearDist = 0.1f; 
int winWidth = 1024;
int winHeight = 768;
float winAspectRatio = 1.0f;

float visZoomFactor = 1.5f;

bool showHelp = false;
bool showStatistics = true;
bool showBoundingVolumes = false;
bool visMode = false;
bool showCreateParams = false;

int currentFrame = -1;

// visualisation view matrix
Matrix4x4 visView; 

//mouse navigation state
int xEyeBegin, yEyeBegin, yMotionBegin, verticalMotionBegin, horizontalMotionBegin = 0;
//int renderMode = RenderTraverser::RENDER_COHERENT;

const int renderTimeSize = 100;
long renderTimes[renderTimeSize];
int renderTimesIdx = 0;
int renderTimesValid = 0;

bool useOptimization = true;


Vector3 amb[2];
Vector3 dif[2];
Vector3 spec[2];

void InitExtensions();
void DisplayVisualization();
void InitGLstate();
void CleanUp();
void SetupEyeView();
void UpdateEyeMtx();
void SetupLighting();

void begin2D();
void end2D();
void output(int x, int y, const char *string);
void keyboard(unsigned char c, int x, int y);
void drawHelpMessage();
void drawStatistics();
void display(void);
void special(int c, int x, int y);
void reshape(int w, int h);
void mouse(int button, int state, int x, int y);
void leftMotion(int x, int y);
void rightMotion(int x, int y);
void middleMotion(int x, int y);
void drawEyeView(void);
void setupVisView(void);
long calcRenderTime(void);
void resetTimer(void);
void calcDecimalPoint(std::string &str, int d);




int main(int argc, char* argv[])
{
        camera = new Camera(winWidth, winHeight);

        glutInitWindowSize(winWidth, winHeight);
        glutInit(&argc, argv);
        glutInitDisplayMode(GLUT_DOUBLE | GLUT_RGBA | GLUT_DEPTH);

        glutCreateWindow("Coherent Hierarchical Culling");

        glutDisplayFunc(display);
        glutKeyboardFunc(keyboard);
        glutSpecialFunc(special);
        glutReshapeFunc(reshape);
        glutMouseFunc(mouse);
        glutIdleFunc(display);
        
        InitExtensions();
        InitGLstate();

        leftMotion(0, 0);
        middleMotion(0, 0);

        BinaryLoader loader;

        //const string filename("house_test.dem");
        //const string filename("city_demo.dem");
        const string filename("city.dem");
        //const string filename("roofs.dem");

        if (loader.Load(filename, sceneEntities))
                cout << "scene " << filename << " loaded" << endl;
        else
                cerr << "loading scene " << filename << " failed" << endl;

        BvhLoader bvhLoader;
        //bvh = bvhLoader.Load("roofs.bvh", sceneEntities);
        bvh = bvhLoader.Load("city.bvh", sceneEntities);
        //bvh = bvhLoader.Load("city_demo.bvh", sceneEntities);
        //bvh = bvhLoader.Load("house_test.bvh", sceneEntities);

        sceneBox = bvh->GetBox();

        //traverser = new FrustumCullingTraverser();
        traverser = new StopAndWaitTraverser();
        traverser->SetHierarchy(bvh);
        traverser->SetRenderState(&state);

        //SetupProjection(800, 600, 60, sceneBox);
        //camera->LookAtBox(sceneBox);
        camera->LookInBox(sceneBox);
        //camera->SetPosition(Vector3(0, 0, -3));
        //camera->SetDirection(Vector3(0, 0, 1));

        /// initialise rendertime array
        for(int i=0; i<renderTimeSize; i++)
                renderTimes[i] = 0;

        glutMainLoop();

        // clean up
        CleanUp();

        return 0;
}


void InitGLstate(void) 
{
        glClearColor(0.5f, 0.5f, 0.8f, 0.0);
        
        glPixelStorei(GL_UNPACK_ALIGNMENT, 1);
        glPixelStorei(GL_PACK_ALIGNMENT,1); 
        
        glDepthFunc(GL_LESS);
        glEnable(GL_DEPTH_TEST);

        SetupLighting();

        glColor3f(1.0f, 1.0f, 1.0f);
        glShadeModel(GL_SMOOTH);
        
        glMaterialf(GL_FRONT, GL_SHININESS, 64);
        glEnable(GL_NORMALIZE);
                        
        glFrontFace(GL_CCW);
        glCullFace(GL_BACK);
        glEnable(GL_CULL_FACE);
        //glDisable(GL_CULL_FACE);
        

        GLfloat ambientColor[] = {0.5, 0.5, 0.5, 1.0};
        GLfloat diffuseColor[] = {1.0, 0.0, 0.0, 1.0};
        GLfloat specularColor[] = {0.0, 0.0, 0.0, 1.0};

        glMaterialfv(GL_FRONT, GL_AMBIENT, ambientColor);
        glMaterialfv(GL_FRONT, GL_DIFFUSE, diffuseColor);
        glMaterialfv(GL_FRONT, GL_SPECULAR, specularColor);
        //setupVisView();
}


void drawHelpMessage(void) 
{
        const char *message[] = 
        {
                "Help information",
                "",
                "'F1'           - shows/dismisses this message",
                "'F2'           - decreases number of objects (valid after scene recreation)",
                "'F3'           - increases number of objects (valid after scene recreation)",
                "'F4'           - decreases box length in z direction (valid after scene recreation)",
                "'F5'           - increases box length in z direction (valid after scene recreation)",
                "'F6'           - decreases object size (valid after scene recreation)",
                "'F7'           - increases object size (valid after scene recreation)",
                "'F8'           - cycles through object types (teapot, ...) (valid after scene recreation)",
                "",
                "'MOUSE-LEFT'   - turn left/right, move forward/backward",
                "'MOUSE-RIGHT'  - turn left/right, move forward/backward",
                "'MOUSE-MIDDLE' - move up/down, left/right",
                "'CURSOR UP'    - move forward",
                "'CURSOR BACK'  - move backward",
                "'CURSOR RIGHT' - turn right",
                "'CURSOR LEFT'  - turn left",
                "",
                "'SPACE'        - cycles through occlusion culling algorithms",
                "'-'            - decreases visibility threshold",
                "'+'            - increases visibility threshold",
                "'C'            - recreates the scene hierarchy",
                "'G'            - enables/disables optimization to take geometry as occluder",
                "'N'            - triggers NV / ARB queries",
                "",
                "'R'            - shows/hides recreation parameters",
                "'S'            - shows/hides statistics",
                "'V'            - shows/hides bounding volumes",
                "",
                "'1'            - shows/hides visualization",
                "'2'            - zooms out visualization",
                "'3'            - zooms in visualization",
                0,
        };
        
        
        int x = 40, y = 42;

        glBlendFunc(GL_SRC_ALPHA, GL_ONE_MINUS_SRC_ALPHA);
        glEnable(GL_BLEND);
        glColor4f(0.0f, 1.0f , 0.0f, 0.2f);  // 20% green. 

        // Drawn clockwise because the flipped Y axis flips CCW and CW. 
        glRecti(winWidth - 30, 30, 30, winHeight - 30);
        
        glDisable(GL_BLEND);
        
        glColor3f(1.0f, 1.0f, 1.0f);
        
        for(int i = 0; message[i] != 0; i++) 
        {
                if(message[i][0] == '\0') 
                {
                        y += 7;
                } 
                else 
                {
                        output(x, y, message[i]);
                        y += 14;
                }
        }

}


void SetupLighting()
{
        glEnable(GL_LIGHTING);
        glEnable(GL_LIGHT0);
        glEnable(GL_LIGHT1);
        //glDisable(GL_LIGHT1);
        //glDisable(GL_LIGHTING);

        //GLfloat ambient[] = {0.5, 0.5, 0.5, 1.0};
        GLfloat ambient[] = {0.2, 0.2, 0.2, 1.0};
        GLfloat diffuse[] = {1.0, 1.0, 1.0, 1.0};
        //GLfloat specular[] = {1.0, 1.0, 1.0, 1.0};
        GLfloat specular[] = {1.0, 1.0, 1.0, 1.0};
            
        //GLfloat lmodel_ambient[] = {0.5f, 0.5f, 0.5f, 1.0};
        GLfloat lmodel_ambient[] = {0.2f, 0.2f, 0.2f, 1.0f};

        glLightfv(GL_LIGHT0, GL_AMBIENT, ambient);
        glLightfv(GL_LIGHT0, GL_DIFFUSE, diffuse);
        glLightfv(GL_LIGHT0, GL_SPECULAR, specular);

        GLfloat position[] = {1.0, 1.0, 1.0, 0.0};
        glLightfv(GL_LIGHT0, GL_POSITION, position);


        ////////////
        //-- second light

        GLfloat ambient1[] = {0.5, 0.5, 0.5, 1.0};
        //GLfloat diffuse1[] = {1.0, 1.0, 1.0, 1.0};
        GLfloat diffuse1[] = {0.5, 0.5, 0.5, 1.0};
        GLfloat specular1[] = {0.5, 0.5, 0.5, 1.0};

        glLightfv(GL_LIGHT1, GL_AMBIENT, ambient1);
        glLightfv(GL_LIGHT1, GL_DIFFUSE, diffuse1);
        glLightfv(GL_LIGHT1, GL_SPECULAR, specular1);
        
        GLfloat position1[] = {0.0, 1.0, 0.0, 1.0};
        glLightfv(GL_LIGHT1, GL_POSITION, position1);

        glLightModelfv(GL_LIGHT_MODEL_AMBIENT, lmodel_ambient);
        glLightModeli(GL_LIGHT_MODEL_LOCAL_VIEWER, GL_TRUE);
        //glLightModeli(GL_LIGHT_MODEL_LOCAL_VIEWER, GL_FALSE);
        //glLightModeli(GL_LIGHT_MODEL_COLOR_CONTROL_EXT, GL_SEPARATE_SPECULAR_COLOR_EXT);
        glLightModeli(GL_LIGHT_MODEL_COLOR_CONTROL_EXT, GL_SINGLE_COLOR_EXT);

}

void SetupEyeView(void)
{
        glMatrixMode(GL_PROJECTION);
        glLoadIdentity();

        gluPerspective(60.0f, 1.0f / winAspectRatio, nearDist, 2.0f * Magnitude(sceneBox.Diagonal()));

        glMatrixMode(GL_MODELVIEW);
        camera->SetupCameraView();

        GLfloat position[] = {0.8f, 1.0f, 1.5f, 0.0f};
        glLightfv(GL_LIGHT0, GL_POSITION, position);

        GLfloat position1[] = {sceneBox.Center().x, sceneBox.Max().y, sceneBox.Center().z, 1.0f};
        //GLfloat position1[] = {-2.0f, 1.0f, 0.0f, 0.0f};
        glLightfv(GL_LIGHT1, GL_POSITION, position1);
}


void display(void) 
{
        char * msg[] = {"Frustum culling only", "Hierarchical stop and wait",
                                    "Coherent hierarchical culling"};

        char msg2[200];
        char msg3[200];
        char msg4[100];
        char msg5[100];
        char msg6[100];
        char msg7[100];
        char msg8[100];


        /*sprintf_s(msg2, "Traversed: %4d, frustum culled: %4d, query culled: %4d (of %d nodes)",
                        traverser.GetNumTraversedNodes(), traverser.GetNumFrustumCulledNodes(),
                        traverser.GetNumQueryCulledNodes(), 
                        traverser.GetHierarchy()->GetNumHierarchyNodes());
*/
        char *optstr[2] = {"", ", using optimization"};
        
        float fps = 1e3f;
        long renderTime = calcRenderTime();
        if (renderTime) fps = 1e3f / (float)renderTime;

        //sprintf_s(msg3, "Threshold: %4d, algorithm rendering time: %ld ms (%3.3f fps), queries: %s", 
        //      traverser.GetVisibilityThreshold(), renderTime / 1000, fps, optstr[useOptimization]);
        sprintf_s(msg3, "render time: %ld ms (%3.3f fps), queries: %s",  renderTime, fps, optstr[useOptimization]);

        string str;
        string str2;

        /*calcDecimalPoint(str, Geometry::CountTriangles(objectType) * traverser.GetNumRenderedGeometry());
        calcDecimalPoint(str2, Geometry::CountTriangles(objectType) * numObjects);

        sprintf_s(msg4, "Rendered objects %d (of %d), rendered triangles: %s (of %s)", 
                        traverser.GetNumRenderedGeometry(), numObjects, str.c_str(), str2.c_str()); 
*/
        
        ++ currentFrame;

        glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);

        // bring eye modelview matrix up-to-date
        SetupEyeView();

        bvh->InitFrame(camera, currentFrame);


        InitTiming();

        long t1, t2;

        t1 = GetTime();

        traverser->SetCamera(camera);

        //traverser->RenderFrustum();

        glEnableClientState(GL_VERTEX_ARRAY);
        glEnableClientState(GL_NORMAL_ARRAY);

        traverser->Render();
/*
        bool usesTextures = false;

        SceneEntityContainer::const_iterator sit, sit_end = sceneEntities.end();

        for (sit = sceneEntities.begin(); sit != sit_end; ++ sit)
        {
                SceneEntity *entity = *sit;

                if (!usesTextures && entity->GetGeometry()->HasTexture())
                {
                        glEnable(GL_TEXTURE_2D);
                        glEnableClientState(GL_TEXTURE_COORD_ARRAY);
                        usesTextures = true;
                }
                else if (usesTextures && !entity->GetGeometry()->HasTexture())
                {
                        glDisable(GL_TEXTURE_2D);
                        glDisableClientState(GL_TEXTURE_COORD_ARRAY);
                        usesTextures = false;
                }

                entity->Render();
        }
*/
        glDisableClientState(GL_VERTEX_ARRAY);
        glDisableClientState(GL_NORMAL_ARRAY);

        glDisable(GL_TEXTURE_2D);
        glDisableClientState(GL_TEXTURE_COORD_ARRAY);
        

        t2 = GetTime();
        long loop_time = TimeDiff(t1, t2);
        //cout<<"t: " << loop_time<<endl;

        /*
        traverser.SetViewpoint(eyePos);
        traverser.SetProjViewMatrix(eyeProjView);
        traverser.Render(renderMode);
        */

        // cycle through rendertime array
        renderTimes[renderTimesIdx] = loop_time;// traverser.GetRenderTime();
        renderTimesIdx = (renderTimesIdx + 1) % renderTimeSize;

        if(renderTimesIdx  > renderTimesValid) 
                renderTimesValid = renderTimesIdx;

        //if(visMode) displayVisualization();
        

        begin2D();
        
        if(showHelp)
        {       
                drawHelpMessage();
        }
        else
        {
                glColor3f(1.0,1.0,1.0);
                //output(10, winHeight-10, msg[renderMode]);

                if(showStatistics)
                {
                        if(showCreateParams)
                        {
                                output(10, winHeight-150, msg8);
                                output(10, winHeight-130, msg7);
                                output(10, winHeight-110, msg6);
                                output(10, winHeight-90,  msg5);
                        }

                        output(10, winHeight-70, msg3);
                        //output(10, winHeight-50, msg4);
                        //output(10, winHeight-30, msg2);
                }
        }
        end2D();

        glutSwapBuffers();
}


#pragma warning( disable : 4100 )
void keyboard(const unsigned char c, const int x, const int y) 
{
        //int threshold;
        //HierarchyNode *hierarchy;

        switch(c) 
        {
        case 27:
                exit(0);
                break;
        case 32: //space
                // renderMode = (renderMode + 1) % RenderTraverser::NUM_RENDERMODES;
                resetTimer();
                //traverser.Render(renderMode);         // render once so stats are updated
                break;
        case 'h':
        case 'H':
                showHelp = !showHelp;
                break;
        case 'v':
        case 'V':
                showBoundingVolumes = !showBoundingVolumes;
                //HierarchyNode::SetRenderBoundingVolume(showBoundingVolumes);
                break;
        case 's':
        case 'S':
                showStatistics = !showStatistics;
                break;
        case '+':
                //threshold = traverser.GetVisibilityThreshold() + 10;
                //traverser.SetVisibilityThreshold(threshold);
                break;
        case '-':
                //threshold = traverser.GetVisibilityThreshold() - 10;
                //if(threshold < 0) threshold = 0;

                //traverser.SetVisibilityThreshold(threshold);          
                break;
        case '1':
                visMode = !visMode;
                break;
        
        case '2':
                visZoomFactor += 0.1;   
                setupVisView();
                break;
        case '3':
                visZoomFactor -= 0.1;
                if(visZoomFactor < 0.1) visZoomFactor = 0.1;
        
                setupVisView();
                break;
        case 'r':
        case 'R':
                showCreateParams = !showCreateParams;
                break;
        case 'g':
        case 'G':
                useOptimization = !useOptimization;
                //traverser.SetUseOptimization(useOptimization);
                break;
                /*
        case 'c':
        case 'C':       
                hierarchy = traverser.GetHierarchy();
                // delete old hierarchy
                if (hierarchy) delete hierarchy; 
                deleteGeometry();

                maxTranslation[2] = -3.0 - zLength;
                numObjects = numNextObjects;
                objectType = nextObjectType;
                
                hierarchy = generateHierarchy(numObjects);
                traverser.SetHierarchy(hierarchy);

                showCreateParams = false;

                traverser.Render(renderMode); // render once to update stats
                resetTimer();
                break;
                */
        default:
                return;
        }

        glutPostRedisplay();
}


void special(const int c, const int x, const int y) 
{
        // used to avoid vertical motion with the keys
        //Vector3 hvec = Vector3(viewDir[0], 0, viewDir[2]);
        
        switch(c) 
        {
        case GLUT_KEY_F1:
                showHelp = !showHelp;
                break;
        case GLUT_KEY_F2:
                //numNextObjects -= 100;
                //if(numNextObjects < 100) numNextObjects = 100;
                break;
        case GLUT_KEY_F3:
       // numNextObjects += 100;
                break;
        case GLUT_KEY_F4:
                //zLength -= 1;
                //if(zLength < 0) zLength = 0;
                break;
        case GLUT_KEY_F5:
                //zLength += 1;
                break;          
        case GLUT_KEY_F6:
                //objectSize -= 0.1;
                //if(objectSize < 0.1) objectSize = 0.1;
                break;
        case GLUT_KEY_F7:
                //objectSize += 0.1;
                break;
        case GLUT_KEY_F8:
                //nextObjectType = (nextObjectType + 1) % Geometry::NUM_OBJECTS;
                break;
        case GLUT_KEY_LEFT:
        //      rotateVectorY(viewDir, 0.2);
                break;
        case GLUT_KEY_RIGHT:
                //rotateVectorY(viewDir, -0.2);
                break;
        case GLUT_KEY_UP:
        //      linCombVector3(eyePos, eyePos, hvec, 0.6);
                break;
        case GLUT_KEY_DOWN:
                //linCombVector3(eyePos, eyePos, hvec, -0.6);
                break;
        default:
                return;

        }

        glutPostRedisplay();
}
#pragma warning( default : 4100 )


void reshape(const int w, const int h) 
{
        winAspectRatio = 1.0f;

        glViewport(0, 0, w, h);
        
        winWidth = w;
        winHeight = h;

        if (w) winAspectRatio = (float) h / (float) w;

        glMatrixMode(GL_PROJECTION);
        glLoadIdentity();

        gluPerspective(60.0f, 1.0f / winAspectRatio, nearDist, 2.0f * Magnitude(sceneBox.Diagonal()));
        glMatrixMode(GL_MODELVIEW);

        glutPostRedisplay();
}


void mouse(int button, int state, int x, int y) 
{
        if ((button == GLUT_LEFT_BUTTON) && (state == GLUT_DOWN))
        {
                xEyeBegin = x;
                yMotionBegin = y;

                glutMotionFunc(leftMotion);
        }
        else if ((button == GLUT_RIGHT_BUTTON) && (state == GLUT_DOWN))
        {
                yEyeBegin = y;
                yMotionBegin = y;

                glutMotionFunc(rightMotion);
        }
        else if ((button == GLUT_MIDDLE_BUTTON) && (state == GLUT_DOWN))
        {
                horizontalMotionBegin = x;
                verticalMotionBegin = y;
                glutMotionFunc(middleMotion);
        }

        glutPostRedisplay();
}


/**     rotation for left/right mouse drag
        motion for up/down mouse drag
*/
void leftMotion(int x, int y) 
{
        static float eyeXAngle = 0.0f;

        Vector3 viewDir = camera->GetDirection();
        Vector3 pos = camera->GetPosition();

        // don't move in the vertical direction
        Vector3 horView(viewDir[0], 0, viewDir[2]);
        
        eyeXAngle = -0.2f *  M_PI * (xEyeBegin - x) / 180.0;

        // rotate view vector
        Matrix4x4 rot = RotationYMatrix(eyeXAngle);
        viewDir = rot * viewDir;

        pos += horView * (yMotionBegin - y) * 0.2f;

        camera->SetDirection(viewDir);
        camera->SetPosition(pos);
        
        xEyeBegin = x;
        yMotionBegin = y;

        glutPostRedisplay();
}


/**     rotation for left/right mouse drag
        motion for up/down mouse drag
*/
void rightMotion(int x, int y) 
{
        static float eyeYAngle = 0.0f;

        Vector3 viewDir = camera->GetDirection();
        Vector3 right = camera->GetRightVector();

        eyeYAngle = -0.2f *  M_PI * (yEyeBegin - y) / 180.0;

        // rotate view vector
        Matrix4x4 rot = RotationAxisMatrix(right, eyeYAngle);
        viewDir = rot * viewDir;

        camera->SetDirection(viewDir);
                
        yEyeBegin = y;
        
        glutPostRedisplay();
}


// strafe
void middleMotion(int x, int y) 
{
        Vector3 viewDir = camera->GetDirection();
        Vector3 pos = camera->GetPosition();

        // the 90 degree rotated view vector 
        // y zero so we don't move in the vertical
        Vector3 rVec(viewDir[0], 0, viewDir[2]);
        
        Matrix4x4 rot = RotationYMatrix(M_PI * 0.5f);
        rVec = rot * rVec;
        
        pos += rVec * (x - horizontalMotionBegin) * 0.1f;
        pos[1] += (verticalMotionBegin - y) * 0.1f;

        camera->SetPosition(pos);

        horizontalMotionBegin = x;
        verticalMotionBegin = y;

        glutPostRedisplay();
}


void InitExtensions(void) 
{
        GLenum err = glewInit();

        if (GLEW_OK != err) 
        {
                // problem: glewInit failed, something is seriously wrong
                fprintf(stderr,"Error: %s\n", glewGetErrorString(err));
                exit(1);
        }
        if  (!GLEW_ARB_occlusion_query)
        {
                printf("I require the GL_ARB_occlusion_query to work.\n");
                exit(1);
        }
}


void begin2D(void) 
{
        glDisable(GL_LIGHTING);
        glDisable(GL_DEPTH_TEST);

        glPushMatrix();
        glLoadIdentity();

        glMatrixMode(GL_PROJECTION);
        glPushMatrix();
        glLoadIdentity();
        gluOrtho2D(0, winWidth, winHeight, 0);
}


void end2D(void) 
{
        glPopMatrix();
        glMatrixMode(GL_MODELVIEW);
        glPopMatrix();

        glEnable(GL_LIGHTING);
        glEnable(GL_DEPTH_TEST);
}


void output(const int x, const int y, const char *string) 
{
        if(string != 0) 
        {
                int len, i;
                glRasterPos2f(x,y);
                len = (int) strlen(string);
                
                for (i = 0; i < len; i++) 
                {
                        glutBitmapCharacter(GLUT_BITMAP_8_BY_13, string[i]);
                }
        }
}

// displays the visualisation of the kd tree node culling
void displayVisualization()
{
        begin2D();
        glBlendFunc(GL_SRC_ALPHA, GL_ONE_MINUS_SRC_ALPHA);
        glEnable(GL_BLEND);
        glColor4f(0.0,0.0,0.0,0.5); 

        glRecti(winWidth, 0, winWidth / 2, winHeight / 2);
        glDisable(GL_BLEND);
        end2D();

        glViewport(winWidth / 2, winHeight / 2, winWidth, winHeight);
        glPushMatrix();
        glLoadMatrixf((float *)visView.x);
        
        glClear(GL_DEPTH_BUFFER_BIT);

        // --- visualization of the occlusion culling
        /*HierarchyNode::SetRenderBoundingVolume(true);
        traverser.RenderVisualization();
        HierarchyNode::SetRenderBoundingVolume(showBoundingVolumes);
*/
        glPopMatrix();
        glViewport(0, 0, winWidth, winHeight);
}

/** Sets up view matrix in order to get a good position 
        for viewing the kd tree node culling
*/
void setupVisView()
{
        const Vector3 up(0.0, 1.0, 0.0);
        
        Vector3 visPos(24, 23, -6);
        
        visPos[0] *= visZoomFactor; 
        visPos[1] *= visZoomFactor; 
        visPos[2] *= visZoomFactor;

        Vector3 visDir = Vector3(-1.3, -1, -1);
        
        //normalize(visDir);
        //look(visView, visPos, visDir, up);
}

// we take a couple of measurements and compute the average
long calcRenderTime()
{
        long result = 0;

        for(int i=0; i<renderTimesValid; i++)
                result += renderTimes[i];
    
        if(renderTimesValid)
                result /= renderTimesValid;

        return result;
}


// reset the timer array for a new traversal method
void resetTimer()
{
        renderTimesValid = 0;
        renderTimesIdx = 0;
}


// cleanup routine after the main loop
void CleanUp()
{
        CLEAR_CONTAINER(sceneEntities);
        DEL_PTR(traverser);

        DEL_PTR(bvh);
}


// this function inserts a dezimal point after each 1000
void calcDecimalPoint(string &str, int d)
{
        vector<int> numbers;
        char hstr[100];

        while (d != 0)
        {
                numbers.push_back(d % 1000);
                d /= 1000;
        }

        // first element without leading zeros
        if (numbers.size() > 0)
        {
                sprintf_s(hstr, "%d", numbers.back());
                str.append(hstr);
        }
        
        for (size_t i = numbers.size() - 2; i >= 0; i--)
        {
                sprintf_s(hstr, ",%03d", numbers[i]);
                str.append(hstr);
        }
}