// add extra methods here
void MyScene::rayTrace(Point3 point, Vector3 ray){
HitRecord* hits = new HitRecord();
transformStack.clear();
transformStack.push_back(Matrix4::identity());
castRayAgainstSubgraph(point, ray, root, hits);
bool gotHit;
double tH, uH, vH;
Point3 pH;
Vector3 nH;
gotHit = hits->getFirstHit(tH, uH, vH, pH, nH);
delete hits;
int col, row;
getScreenCoord(point+ray, col, row);
int idx = pxIdx(col, row);
if (gotHit){
for (Light& l : lights){
Point3 lPos = l.getPos();
castLight(lPos, pH, l, 0, 0, NULL);
}
}
else{
pixelArray[idx] = (unsigned char)(background[0] * 255);
pixelArray[idx + 1] = (unsigned char)(background[1] * 255);
pixelArray[idx + 2] = (unsigned char)(background[2] * 255);
}
}
void MyScene::castRayAgainstSubgraph(Point3 p, Vector3 v, Tree* graph, HitRecord* hits){
for (Node* n : graph->rootNodes){
Matrix4 trans = transformStack.back();
trans = trans*n->transformations;
Matrix4 invTrans = trans.inverse();
if (n->object){
Vector4 pObj4 = invTrans*Vector4(p[0], p[1], p[2], 1);
Vector4 vObj4 = invTrans*Vector4(v[0], v[1], v[2], 0);
vObj4.normalize();
Shape* s;
switch (n->object->type){
case CUBE:{
s = cube;
} break;
case SPHERE:{
s = sphere;
} break;
case CONE:{
s = cone;
} break;
case CYLINDER:{
s = cylinder;
} break;
}
Point3 pObj = Point3(pObj4[0], pObj4[1], pObj4[2]);
Vector3 vObj = Vector3(vObj4[0], vObj4[1], vObj4[2]);
HitRecord* hr = s->intersect(pObj, vObj);
hr->sortHits();
bool gotHit;
double tH,uH,vH;
Point3 pH;
Vector3 nH;
gotHit = hr->getFirstHit(tH, uH, vH, pH, nH);
delete hr;
if (gotHit && tH > 0){
pH = trans * pH;
nH = invTrans.transpose() * nH;
nH.normalize();
tH = (pH - p).length();
if (tH < hits->getMinT()){
hits->clear();
hits->addHit(tH, uH, vH, pH, nH, (void*)n->object);
}
}
}
else if (n->subgraph){
transformStack.push_back(trans);
castRayAgainstSubgraph(p, v, n->subgraph, hits);
transformStack.pop_back();
}
}
}
void IntersectionUI::drawHits(HitRecord& hr) {
double t, u, v;
Point3 p;
Vector3 n;
glDisable(GL_LIGHTING);
while (hr.getFirstHit(t, u, v, p, n)) {
glPointSize(8.0f);
glLineWidth(6.0f);
glColor3f(1.0f, 0.0f, 0.0f);
glBegin(GL_POINTS);
glVertex3d(p[0], p[1], p[2]);
glEnd();
glColor3f(0.2f, 0.2f, 0.2f);
glBegin(GL_LINES);
glVertex3d(p[0], p[1], p[2]);
glVertex3d(p[0] + 0.5 * n[0], p[1] + 0.5 * n[1], p[2] + 0.5 * n[2]);
glEnd();
glLineWidth(1.0f);
glPointSize(1.0f);
hr.removeFirstHit();
}
}
void MyScene::castLight(const Point3& src, const Point3& dst, Light& l, int depth, double distance, Color* reflectedColor){
Vector3 ray = dst - src;
ray.normalize();
HitRecord* hits = new HitRecord();
castRayAgainstSubgraph(src, ray, root, hits);
double t, u, v;
Point3 p;
Vector3 n;
hits->getFirstHit(t, u, v, p, n);
Object* o = (Object*)hits->getFirstHitObj();
delete hits;
int col, row;
getScreenCoord(dst, col, row);
int idx = pxIdx(col, row);
Color screenColor = Color(pixelArray[idx] / (float)255, pixelArray[idx+1] / (float)255, pixelArray[idx+2] / (float)255);
//ambient
screenColor[0] += o->ambient[0];
screenColor[1] += o->ambient[1];
screenColor[2] += o->ambient[2];
//not in shadow
double diff = (dst - p).length();
if (diff < EPSILON){
Color lightColor = l.getColor();
distance += (dst-src).length();
Point3 falloff = l.getFalloff();
double attenuation = 1 / (double)(falloff[0] + falloff[1] * distance + falloff[2] * distance*distance);
//diffuse
double dot = n*(-ray);
if (dot > 0){
screenColor[0] += (GLfloat)(o->diffuse[0] * lightColor[0] * attenuation*dot);
screenColor[1] += (GLfloat)(o->diffuse[1] * lightColor[1] * attenuation*dot);
screenColor[2] += (GLfloat)(o->diffuse[2] * lightColor[2] * attenuation*dot);
}
//reflect
++depth;
if ((depth < MAX_RECURSION_DEPTH) && (attenuation > EPSILON)){
Vector3 reflectedRay = 2 * (ray * n) * n - ray;
reflectedRay.normalize();
Point3 newSrc = p + EPSILON*reflectedRay;
Point3 newDst = p + reflectedRay;
double r = o->reflect[0] * lightColor[0] * attenuation*dot;
double g = o->reflect[1] * lightColor[1] * attenuation*dot;
double b = o->reflect[2] * lightColor[2] * attenuation*dot;
if (r > INVISIBLE || g > INVISIBLE || b > INVISIBLE){
Color* reflect = new Color((GLfloat)r, (GLfloat)g, (GLfloat)b);
castLight(newSrc, newDst, l, depth, distance, reflect);
delete reflect;
}
}
//specular
Vector3 reflection = ray - 2 * n*(ray*n);
reflection.normalize();
Vector3 look = camera.getLook();
look.normalize();
dot = reflection*(-look);
if (dot > 0){
screenColor[0] += (GLfloat)(o->specular[0] * lightColor[0] * attenuation * pow(dot, o->shine));
screenColor[1] += (GLfloat)(o->specular[1] * lightColor[1] * attenuation * pow(dot, o->shine));
screenColor[2] += (GLfloat)(o->specular[2] * lightColor[2] * attenuation * pow(dot, o->shine));
}
}
if (screenColor[0] > 1){
screenColor[0] = 1;
}
if (screenColor[1] > 1){
screenColor[1] = 1;
}
if (screenColor[2] > 1){
screenColor[2] = 1;
}
pixelArray[idx] = (unsigned char)roundToNearest(screenColor[0]*255);
pixelArray[idx + 1] = (unsigned char)roundToNearest(screenColor[1] * 255);
pixelArray[idx + 2] = (unsigned char)roundToNearest(screenColor[2] * 255);
}
