Example #1
0
//Test
// now the object is in the local coordinate rather than the global
bool Square::intersectLocal( const ray& r, isect& i ) const
{
	// get the parameters of the ray 
	Vec3d p = r.getPosition();
	Vec3d d = r.getDirection();

	// if the ray is perpendicular to the z-axis
	if( d[2] == 0.0 ) {
		return false;
	}

	// calculate the value of t
	double t = -p[2]/d[2];

	// if the intersection is too close to the source
	// then we don't count that as a intersection
	if( t <= RAY_EPSILON ) {
		return false;
	}

	
	Vec3d P = r.at( t );

	if( P[0] < -0.5 || P[0] > 0.5 ) {	
		return false;
	}

	if( P[1] < -0.5 || P[1] > 0.5 ) {	
		return false;
	}

	i.obj = this;
	i.t = t;
	if( d[2] > 0.0 ) {
		i.N = Vec3d( 0.0, 0.0, -1.0 );
	} else {
		i.N = Vec3d( 0.0, 0.0, 1.0 );
	}

    i.setUVCoordinates( Vec2d(P[0] + 0.5, P[1] + 0.5) );
	return true;
}
Example #2
0
//Test
bool Square::intersectLocal(ray& r, isect& i) const
{
	Vec3d p = r.getPosition();
	Vec3d d = r.getDirection();

	if( d[2] == 0.0 ) {
		return false;
	}

	double t = -p[2]/d[2];

	if( t <= RAY_EPSILON ) {
		return false;
	}

	Vec3d P = r.at( t );

	if( P[0] < -0.5 || P[0] > 0.5 ) {	
		return false;
	}

	if( P[1] < -0.5 || P[1] > 0.5 ) {	
		return false;
	}

	i.obj = this;
	i.setMaterial(this->getMaterial());
	i.t = t;
	if( d[2] > 0.0 ) {
		i.N = Vec3d( 0.0, 0.0, -1.0 );
	} else {
		i.N = Vec3d( 0.0, 0.0, 1.0 );
	}

    i.setUVCoordinates( Vec2d(P[0] + 0.5, P[1] + 0.5) );
	return true;
}
Example #3
0
bool Box::intersectLocal( const ray& r, isect& i ) const
{

        Vec3d p = r.getPosition();
        Vec3d d = r.getDirection();

        int it;
        double x, y, t, bestT; 
        int mod0, mod1, mod2, bestIndex;

        bestT = HUGE_DOUBLE;
        bestIndex = -1;

        for(it=0; it<6; it++){ 
                mod0 = it%3;

                if(d[mod0] == 0){
                        continue;
                }
                
                t = ((it/3) - 0.5 - p[mod0]) / d[mod0];                 

                if(t < RAY_EPSILON || t > bestT){
                        continue;
                }

                mod1 = (it+1)%3;
                mod2 = (it+2)%3;
                x = p[mod1]+t*d[mod1];
                y = p[mod2]+t*d[mod2];
                
                if(     x<=0.5 && x>=-0.5 &&
                        y<=0.5 && y>=-0.5)
                {
                        if(bestT > t){
                                bestT = t;
                                bestIndex = it;
                        }
                }                       
                
        }

        if(bestIndex < 0) return false;
        
        i.setT(bestT);
        i.setObject(this);

		Vec3d intersect_point = r.at(i.t);

		int i1 = (bestIndex + 1) % 3;
		int i2 = (bestIndex + 2) % 3;

        if(bestIndex < 3)
		{
                i.setN(Vec3d(-double(bestIndex == 0), -double(bestIndex == 1), -double(bestIndex == 2)));
				i.setUVCoordinates( Vec2d(	0.5 - intersect_point[ min(i1, i2) ], 
											0.5 + intersect_point[ max(i1, i2) ] ) );
		}
        else
		{
                i.setN(Vec3d(double(bestIndex==3), double(bestIndex == 4), double(bestIndex == 5)));
				i.setUVCoordinates( Vec2d(	0.5 + intersect_point[ min(i1, i2) ],
											0.5 + intersect_point[ max(i1, i2) ] ) );

		}
        return true;

}