primitiveshapes.cpp

file code.zip are used to implement ray tracing technology.

#include "PrimitiveShapes.h"

//@$@$@$@$@$@$@$@$@$@ Plane class @$@$@$@$@$@$@$@$@$
Plane::Plane() {};

void Plane::makeExtentPoints(PointCluster& clust) {}
bool Plane::hit(Ray &r, Intersection &inter)
{
    Ray genRay;
    inter.numHits = 0;
    xfrmRay(genRay, r);

    double denom = genRay.getDir().z;
    if(fabs(denom) < 0.001) return false;

    double time = -genRay.getStart().z/denom;
    if(time<=0.0) return false;

    double hx = genRay.getStart().x + genRay.getDir().x *time;
    double hy = genRay.getStart().y + genRay.getDir().y *time;

    inter.numHits=1;
    inter.hit[0].hitObject = this;
    inter.hit[0].hitTime = time;
    inter.hit[0].isEntering = true;
    inter.hit[0].surface=0;
    inter.hit[0].hitPoint.set(hx,hy,0);
    inter.hit[0].hitNormal.set(0,0,1);

    return true;
}

void Plane::drawOpenGL() {}

void Plane::print()
{
    cout << "Object: Plane\n";
    transf.print();
}


//@$@$@$@$@$@$@$@$@$@ Checkerboard class @$@$@$@$@$@$@$@$@$
Checkerboard::Checkerboard()
{
	checkObj1 = checkObj2 = NULL;
	dx = dy = 1;
}

Checkerboard::Checkerboard(double newDX, double newDY)
{
	checkObj1 = checkObj2 = NULL;
	dx = newDX; dy = newDY;
}

void Checkerboard::makeExtentPoints(PointCluster& clust) {}
bool Checkerboard::hit(Ray &r, Intersection &inter)
{
	// Create the checkerboard materials
	if(checkObj1 == NULL)
	{
		// Create the new objects
		checkObj1 = new Plane();
		checkObj2 = new Plane();

		// Copy the transformation matrices
		checkObj1->transf.set(this->transf);
		checkObj2->transf.set(this->transf);
		checkObj1->invTransf.set(this->invTransf);
		checkObj2->invTransf.set(this->invTransf);

		// Copy the material
		checkObj1->mtrl.set(this->mtrl);
		checkObj2->mtrl.set(this->mtrl);

		// Change the material properties
		checkObj1->mtrl.ambient.set(0.15, 0.15, 0.15);
		checkObj1->mtrl.diffuse.set(0.15, 0.15, 0.15);
		checkObj1->mtrl.specular.set(0.15, 0.15, 0.15);

		checkObj2->mtrl.ambient.set(0.8, 0.8, 0.8);
		checkObj2->mtrl.diffuse.set(0.8, 0.8, 0.8);
		checkObj2->mtrl.specular.set(0.8, 0.8, 0.8);
	}

    Ray genRay;
    inter.numHits = 0;
    xfrmRay(genRay, r);

    double denom = genRay.getDir().z;
    if(fabs(denom) < 0.001) return false;

    double time = -genRay.getStart().z/denom;
    if(time<=0.0) return false;

    double hx = genRay.getStart().x + genRay.getDir().x *time;
    double hy = genRay.getStart().y + genRay.getDir().y *time;

	unsigned int checkState = (int)(floor(hx/dx) + floor(hy/dy));
	if(checkState%2 == 0) inter.hit[0].hitObject = checkObj1;
	else inter.hit[0].hitObject = checkObj2;

    inter.numHits=1;
    inter.hit[0].hitTime = time;
    inter.hit[0].isEntering = true;
    inter.hit[0].surface=0;
    inter.hit[0].hitPoint.set(hx,hy,0);
    inter.hit[0].hitNormal.set(0,0,1);

    return true;
}

void Checkerboard::drawOpenGL() {}

void Checkerboard::print()
{
    cout << "Object: Checkerboard\n";
    transf.print();
}

//@$@$@$@$@$@$@$@$@$@ Square class @$@$@$@$@$@$@$@$@$
Square::Square() {}

void Square::makeExtentPoints(PointCluster& clust) {}
bool Square::hit(Ray &r, Intersection &inter)
{
    Ray genRay;
    inter.numHits=0;
    xfrmRay(genRay, r);

    double denom = genRay.getDir().z;
    if(fabs(denom) < 0.001) return false;

    double time = -genRay.getStart().z/denom;
    if(time<=0.0) return false;

    double hx=genRay.getStart().x + genRay.getDir().x *time;
    double hy=genRay.getStart().y + genRay.getDir().y *time;
    if((hx>1.0)||(hx < -1.0)) return false;
    if((hy>1.0)||(hy < -1.0)) return false;

    inter.numHits=1;
    inter.hit[0].hitObject=this;
    inter.hit[0].hitTime=time;
    inter.hit[0].isEntering=false;
    inter.hit[0].surface=0;
    inter.hit[0].hitPoint.set(hx,hy,0);
    inter.hit[0].hitNormal.set(0,0,1);

    return true;
}

void Square::drawOpenGL() {}
void Square::print()
{
    cout << "Object: Square\n";
    transf.print();
}


//@$@$@$@$@$@$@$@$@ Cube class $@$@$@$@$@$@$@$@$@$@
Cube::Cube() {}

void Cube::makeExtentPoints(PointCluster& clust) {}

bool Cube::hit(Ray &r, Intersection &inter)
{
    Ray genRay;
    xfrmRay(genRay, r);

    double tHit, numer, denom;
    double tIn = -100000.0, tOut = 100000.0;
    int inSurf, outSurf;

    float rayDirX = genRay.getDir().x,
          rayDirY = genRay.getDir().y,
          rayDirZ = genRay.getDir().z,
          rayStrX = genRay.getStart().x,
          rayStrY = genRay.getStart().y,
          rayStrZ = genRay.getStart().z;
        
    
    // Loop through the six faces of the cube
    for(int i=0; i < 6; i++)
    {
        // Set-up the plane fraction for this face of the cube
        switch(i)
        {
            case 0: // Top of cube (XZ-plane up 1.0)
                numer = 1.0 - rayStrY;
                denom = rayDirY;
                break;

            case 1: // Bottom of cube (XZ-plane down 1.0)
                numer = 1.0 + rayStrY;
                denom = - rayDirY;
                break;

            case 2: // Right of cube (YZ-plane right 1.0)
                numer = 1.0 - rayStrX;
                denom = rayDirX;
                break;

            case 3: // Left of cube (YZ-plane left 1.0)
                numer = 1.0 + rayStrX;
                denom = - rayDirX;
                break;

            case 4: // Front of cube (XY-plane forward 1.0)
                numer = 1.0 - rayStrZ;
                denom = rayDirZ;
                break;

            case 5: // Back of cube (XY-plane back 1.0)
                numer = 1.0 + rayStrZ;
                denom = - rayDirZ;
                break;
        }

        if(fabs(denom) < 0.00001) // Ray is parallel to this face
        {
            if(numer < 0) return false;	// Ray is outside
        }
        else	// Ray is not parallel
        {
            tHit = numer/denom;
            if(denom > 0) // We are exiting the cube
            {
                if(tHit < tOut) // A new earlier Exit time
                    { tOut = tHit; outSurf = i; }
            }
            else // We are entering the cube
            {
                if(tHit > tIn) // A new later Enter time
                    { tIn = tHit; inSurf = i; }
            }
            
        }

        if(tIn >= tOut) return false;	// Miss (early out)
    }

    // Now create the hits for the intersection
    int num = 0;
    if(tIn > 0.00001)	// Is first hit in front of the eye
    {
        inter.hit[num].hitTime = tIn;
        inter.hit[num].surface = inSurf;
        inter.hit[num].isEntering = true;
        inter.hit[num].hitObject = this;

        Point3 PO(genRay.calculatePointOnRay(tIn));
        Point3 N(cubeNormal(inSurf));
        inter.hit[num].hitPoint.set(PO.x, PO.y, PO.z);
        inter.hit[num].hitNormal.set(N.x, N.y, N.z);
        num++;
    }

    if(tOut > 0.00001)	// Is second hit in front of the eye
    {
        inter.hit[num].hitTime = tOut;
        inter.hit[num].surface = outSurf;
        inter.hit[num].isEntering = false;
        inter.hit[num].hitObject = this;

        Point3 PO(genRay.calculatePointOnRay(tOut));
        Point3 N(cubeNormal(outSurf));
        inter.hit[num].hitPoint.set(PO.x, PO.y, PO.z);
        inter.hit[num].hitNormal.set(N.x, N.y, N.z);
        num++;
    }

    inter.numHits = num;
    return (num > 0);
}

Point3 Cube::cubeNormal(int surface)
{
    Point3 norm;
    switch(surface)
    {
        case 0: norm.set( 0, 1, 0); break;
        case 1: norm.set( 0,-1, 0); break;
        case 2: norm.set( 1, 0, 0); break;
        case 3: norm.set(-1, 0, 0); break;
        case 4: norm.set( 0, 0, 1); break;
        case 5: norm.set( 0, 0,-1); break;
    }

    return norm;
}

void Cube::drawOpenGL() 
{
RGBpixmap pix[6];
	glEnable(GL_TEXTURE_2D);
	pix[0].readBMPFile("floor.bmp");   //t?o pixmap b?ng gi?i thu?t
	printf("HELLO\n");
	pix[0].setTexture(2001);   
	printf("hellp\n");
	pix[1].readBMPFile("forest.bmp"); // t?o pixmap t? t?p tin h靚h ?nh
	pix[1].setTexture(2002);
	pix[2].readBMPFile("money.bmp"); // t?o pixmap t? t?p tin h靚h ?nh
	pix[2].setTexture(2003);
	pix[3].readBMPFile("lemon.bmp"); // t?o pixmap t? t?p tin h靚h ?nh
	pix[3].setTexture(2004);
	pix[4].readBMPFile("wall.bmp"); // t?o pixmap t? t?p tin h靚h ?nh
	pix[4].setTexture(2005);
	glTexEnvf(GL_TEXTURE_ENV, GL_TEXTURE_ENV_MODE, GL_DECAL);
	glPushMatrix();
	glBindTexture(GL_TEXTURE_2D, 2001);
	glBegin(GL_QUADS);
		glTexCoord2f(0.0, 0.0); 
		glVertex3f(-1.0f, 1.0f, -1.0f);
		glTexCoord2f(1.0,  0.0); 
		glVertex3f(-1.0f, 1.0f,  1.0f);
		glTexCoord2f( 1.0,  1.0);