//void lightCalculation(){
float rayCalculation(float levelDetail){
/* Default closest interection to 3000*/
float closestIntersection = 3000;
int currentSphere = -1;
int i;
for(i = 0; i < numberOfSpheres; i++){
//if Ray and Sphere intersect
if((intersectRaySphere(&ray, &spheres[i], &closestIntersection)) == 1){
currentSphere = i;
}
}
//if not intersection found return
if(currentSphere == -1){
return levelDetail;
}
//Finding the scaler value of the closestInterestion and the ray directions
Vector scaled = vectorScalar(closestIntersection, &ray.direction);
//Starting at the new location just found
Vector newStart = vectorAddition(&ray.start, &scaled);
//Find the normal for this new vector at the point of intersection
Vector normal = vectorSubtraction(&newStart, &spheres[currentSphere].pos);
float temp = vectorDotProduct(&normal, &normal);
//if there's no dot product of the normal vector return
if(temp == 0){
return levelDetail;
}
temp = (1.0 / sqrtf(temp));
//Setting the noram vector
normal = vectorScalar(temp, &normal);
//calucting the lights and shadows
levelDetail = lightCalculation(levelDetail, currentSphere, &newStart, &normal);
// The reflected ray start and direction
ray.start = newStart;
float reflect = 2 * vectorDotProduct(&ray.direction, &normal);
Vector tmp = vectorScalar(reflect, &normal);
ray.direction = vectorSubtraction(&ray.direction, &tmp);
return levelDetail;
}
/* Check if the ray and sphere intersect */
int intersectRaySpherePartB(Ray *ray, Sphere *sphere){
float A, B, C, root;
/* The vector dot product of the direction */
A = vectorDotProduct(&ray->direction, &ray->direction);
/* The vector distance from the start of
the ray and the position of the circle. */
Vector distance = vectorSubtraction(&ray->start, &sphere->pos);
/* Postiion - c */
B = 2 * vectorDotProduct(&ray->direction, &distance);
/* (postion - c)^2 - r^2 */
C = vectorDotProduct(&distance, &distance) - (sphere->radius * sphere->radius);
/* Solving the discriminant */
root = B * B - 4 * A * C;
/* If the root is negtive return false/zero */
if(root < 0){
return 0;
}
return 1;
}
/* Calculating the lights and shadows*/
float lightCalculation(float levelDetail, int currentSphere, Vector *newStart, Vector *normal){
// Determine the current material
int getMaterialIndexValue = (spheres + currentSphere)->material;
Material currentMaterial = materials[getMaterialIndexValue];
//Find the value of the light at the current position
int j;
for( j = 0; j < numberOfLights; j++){
Light currentLight = lights[j];
Vector distance = vectorSubtraction(¤tLight.pos, newStart);
//If the dot product of the normal and the distance is less than or equal to zero
//coutinue
if(vectorDotProduct(normal, &distance) <= 0) {
continue;
}
float closestIntersection;
//setting the new closesInterection point
closestIntersection = sqrtf(vectorDotProduct(&distance,&distance));
if(closestIntersection <= 0) {
continue;
}
Ray lightRay;
lightRay.start = *newStart;
lightRay.direction = vectorScalar((1/closestIntersection), &distance);
// Calculate shadows
int shadow = 0;
int k;
for (k = 0; k < numberOfSpheres; ++k){
if (intersectRaySphere(&lightRay, &spheres[k], &closestIntersection) == 1){
shadow = 0;
break;
}
}
if (shadow != 1){
//Calculating the lambert value
float lambert = vectorDotProduct(&lightRay.direction, normal) * levelDetail;
//Processing the Lambert Diffusion
LambertDiffusion(lambert, currentLight, currentMaterial);
}
}
levelDetail *= currentMaterial.reflection;
return levelDetail;
}
Line *createLine(vector camera, png_uint_32 x, png_uint_32 y) {
Line *retval = malloc(sizeof(Line));
retval->start = camera;
vector planePoint = vectorCreate(-8.0 + 16.0 * ((double)x / (double)WIDTH), 0.0, 10.0 - 10.0 * ((double)y / (double)HEIGHT));
vector dir = vectorSubtraction(planePoint, camera);
retval->end = vectorAddition(camera, vectorMultiply(dir,50));
return retval;
}
void SkeletonState::renderLimb(SkeletonPoint& pt1, SkeletonPoint& pt2)
{
if(pt1.confidence <= 0.5 || pt2.confidence <= 0.5)
return;
float a[3] = {pt1.x, pt1.y, pt1.z};
float b[3] = {pt2.x, pt2.y, pt2.z};
// vector formed by the two joints
float c[3];
vectorSubtraction(a, b, c);
// glu cylinder vector
float z[3] = {0,0,1};
// r is axis of rotation about z
float r[3];
vectorCrossProduct(z, c, r);
// get angle of rotation in degrees
float angle = 180./M_PI * acos((vectorDotProduct(z, c)/vectorMagnitude(c)));
glPushMatrix();
// translate to second joint
glTranslatef(pt2.x, pt2.y, pt2.z);
glRotatef(angle, r[0], r[1], r[2]);
// set up quadric object
GLUquadricObj* quadObj = gluNewQuadric();
gluCylinder(quadObj, 10, 10, vectorMagnitude(c), 10, 10);
glPopMatrix();
// delete used quadric
gluDeleteQuadric(quadObj);
}
/* Check if the ray and sphere intersect */
int intersectRaySphere(Ray *ray, Sphere *sphere, float *closestIntersection){
float A,B,C;
int intersect = 0;
/* A = direction * direction , the vector dot product of the direction */
A = vectorDotProduct(&ray->direction, &ray->direction);
/* The vector distance from the start of
the ray and the position of the circle. */
Vector distance = vectorSubtraction(&ray->start, &sphere->pos);
/* 2*(postion - c) */
B = 2 * vectorDotProduct(&ray->direction, &distance);
/* (position - c)^2 - r^2 */
C = vectorDotProduct(&distance, &distance) - (sphere->radius * sphere->radius);
/*Solve the Quadratic Formula */
intersect = quadraticFormula(A, B, C, closestIntersection);
return intersect;
}
vector rayTrace(Line *ray, Primitive **primitives, Light **lights, float r_idx) {
Intersection *bestIntersection = NULL;
vector retval = vectorCreate(0.0, 0.0, 0.0);
for (int p = 0; p < 10; p++) {
if (!primitives[p])
break;
Intersection *thisIntersection = primitiveIntersect(primitives[p], ray);
if (!bestIntersection) {
bestIntersection = thisIntersection;
continue;
}
if (thisIntersection && thisIntersection->distance < bestIntersection->distance) {
free(bestIntersection);
bestIntersection = thisIntersection;
}
}
if (bestIntersection) {
Primitive *primitive = bestIntersection->primitive;
Material *material = primitive->material;
vector mcolor = vectorMultiply(material->color, 0.0);
vector N = primitiveNormal(primitive, bestIntersection);
vector V = vectorUnit(vectorSubtraction(ray->end, ray->start));
for (int l = 0; l < 2; l++) {
Light *light = lights[l];
vector lvec = vectorSubtraction(light->location, bestIntersection->intersectionPoint);
vector pcolor = material->color;
vector lcolor = light->color;
Intersection *linter = NULL;
Line *lightRay = makeLine(bestIntersection->intersectionPoint, light->location);
float shade = 0.0;
for (int p = 0; p < 3; p++) {
if (primitives[p] == primitive)
continue;
if ((linter = primitiveIntersect(primitives[p], lightRay)))
shade += 1.0 - linter->primitive->material->transparency;
}
free(lightRay);
if (shade < 1.0) {
if (material->specular > 0.0) {
float sintensity = 0.0;
vector L = vectorUnit(lvec);
vector R = vectorSubtraction(L, vectorMultiply(N, 2 * vectorDotProduct(L,N)));
float dot = vectorDotProduct(V, R);
if (dot > 0.0) {
sintensity = pow(dot, 20) * material->specular * light->intensity * (1.0 - shade);
}
if (sintensity > 0.0) {
mcolor = vectorAddition(mcolor, vectorMultiply(lcolor, sintensity));
}
}
if (material->diffuse > 0.0) {
float dintensity = material->diffuse * vectorDotProduct(vectorUnit(lvec), primitive->normal(bestIntersection->primitive, bestIntersection)) * light->intensity * (1.0 - shade);
if (dintensity > 0.0) {
mcolor = vectorAddition(mcolor, vectorMultiply(vectorCProduct(pcolor, lcolor), dintensity));
}
}
}
free(linter);
}
if (material->reflection > 0.0) {
vector R = vectorUnit(vectorSubtraction(V, vectorMultiply(N, 2 * vectorDotProduct(V,N))));
Line *rline = makeLine(vectorAddition(bestIntersection->intersectionPoint, vectorMultiply(R, EPS)), vectorAddition(bestIntersection->intersectionPoint, vectorMultiply(R, 30)));
vector rcolor = rayTrace(rline, primitives, lights, r_idx);
mcolor = vectorAddition(vectorMultiply(mcolor, 1.0 - material->reflection), vectorMultiply(rcolor, material->reflection));
free(rline);
}
if (material->transparency > 0) {
float refraction = material->refraction;
float n = r_idx / refraction;
vector Nr = vectorMultiply(N, bestIntersection->direction);
float cosI = - vectorDotProduct(Nr, V);
float cosT2 = 1.0 - n * n * (1.0 - cosI * cosI);
if (cosT2 > 0.0) {
vector T = vectorAddition(vectorMultiply(V, n), vectorMultiply(Nr, n * cosI - sqrt(cosT2)));
Line *rline = makeLine(vectorAddition(bestIntersection->intersectionPoint, vectorMultiply(T, EPS)), vectorAddition(bestIntersection->intersectionPoint, vectorMultiply(T, 30)));
vector rfcol = rayTrace(rline, primitives, lights, r_idx);
mcolor = vectorAddition(vectorMultiply(mcolor, 1.0 - material->transparency), vectorMultiply(rfcol, material->transparency));
free(rline);
}
}
retval = mcolor;
free(bestIntersection);
}
return retval;
}
