OpenMP in ray-tracing program with two nested for loops crashing - multithreading

Question

I am using OpenMP in VisualStudio 2015.
In my Ray-Tracing algorithm I have the following code
int x, y;
#pragma omp parallel for private(y)
for (x = 0; x < sWidth; x++) {
for (y = 0; y < sHeight; y++) {
thisone = y*sWidth + x;
for (int aax = 0; aax < aadepth; aax++) {
for (int aay = 0; aay < aadepth; aay++) {
aa_index = aay*aadepth + aax;
srand(time(0));
//anti-aliasing
if (sWidth > sHeight) {
//the image is wider than it is tall
xamnt = ((x + (double)aax / (aadepth - 1)) / sWidth)*aspectratio - (((sWidth - sHeight) / sHeight) / 2);
yamnt = ((sHeight - y) + (double)aax / (aadepth - 1)) / sHeight;
}
else if (sHeight > sWidth) {
//the image is taller than it is wide
xamnt = (x + (double)aax / (aadepth - 1)) / sWidth;
yamnt = (((sHeight - y) + (double)aax / (aadepth - 1)) / sHeight) / aspectratio - (((sHeight - sWidth) / sWidth) / 2);
}
else {
//the image is square
xamnt = (x + (double)aax / (aadepth - 1)) / sWidth;
yamnt = ((sHeight - y) + (double)aax / (aadepth - 1)) / sHeight;
}
//camera ray
Vect cam_ray_origin = scene_cam.getCameraPosition();
Vect cam_ray_direction = camdir.vectAdd(camright.vectMult(xamnt - 0.5).vectAdd(camdown.vectMult(yamnt - 0.5))).normalize();
Ray cam_ray(cam_ray_origin, cam_ray_direction);
vector<double> intersections;
for (int index = 0; index < scene_objects.size(); index++) {
intersections.push_back(scene_objects.at(index)->findIntersection(cam_ray));
}
int index_of_winning_object = winningObjectIndex(intersections);
if (index_of_winning_object == -1) {
//set the background black
tempRed[aa_index] = 0;
//cout << tempRed[aa_index];
tempGreen[aa_index] = 0;
tempBlue[aa_index] = 0;
//return color
}
else {
//index corresponds to an object in our scene
if (intersections.at(index_of_winning_object) > accuracy) {
//determine the position and direction vectors at the point of intersection
Vect intersection_position = cam_ray_origin.vectAdd(cam_ray_direction.vectMult(intersections.at(index_of_winning_object)));
Vect intersecting_ray_direction = cam_ray_direction;
//color in the points
Color intersection_color = getColorAt(intersection_position,
intersecting_ray_direction,
scene_objects, index_of_winning_object,
light_sources, accuracy, ambientlight);
tempRed[aa_index] = intersection_color.getColorRed();
tempGreen[aa_index] = intersection_color.getColorGreen();
tempBlue[aa_index] = intersection_color.getColorBlue();
}
}
}
}
//adding the colors to each pixel
//average the pixel color
double totalRed = 0;
double totalGreen = 0;
double totalBlue = 0;
for (int iRed = 0; iRed < aadepth*aadepth; iRed++) {
totalRed = totalRed + tempRed[iRed];
}
for (int iGreen = 0; iGreen < aadepth*aadepth; iGreen++) {
totalGreen = totalGreen + tempGreen[iGreen];
}
for (int iBlue = 0; iBlue < aadepth*aadepth; iBlue++) {
totalBlue = totalBlue + tempBlue[iBlue];
}
double avgRed = totalRed / (aadepth*aadepth);
double avgGreen = totalGreen / (aadepth*aadepth);
double avgBlue = totalBlue / (aadepth*aadepth);
pixels[thisone].r = avgRed;
pixels[thisone].g = avgGreen;
pixels[thisone].b = avgBlue;
}
}
saveimg("scene_anti-aliased_thread_test1.bmp", pixels);
I used several different functions from OpenMP. I tried #pragma omp parallel and #pragma omp parallel for with #pragma omp parallel for reduction() and #pragma omp parallel for private().
But nothing seems to work.
When I use the #pragma omp parallel just before the xand y for loops I get a "Microsoft C/C++ optimizing compilator has stopped working".Severity Code Description Project File Line Suppression State
Error C3017 termination test in OpenMP 'for' statement has improper form Ray-Tracing e:\utility programs\vs - c++\ray-tracing\ray-tracing\main.cpp 258
Error C1903 unable to recover from previous error(s); stopping compilation Ray-Tracing e:\utility programs\vs - c++\ray-tracing\ray-tracing\main.cpp 258
Why am I getting these errors?
When I use the same #pragma omp parallel before the aax and aay for loops it renders the image even slower.
Now I guess that, when I use the #pragma omp parallel for in the second two nested for loops it just computes the code several times and that's it. It doesn't do anything.
But I honestly have no idea, I just started playing around with openMP.
Please help with - which OpenMP functions should I use and where should I put them?
Thanks!
P.S. - the code seen is mainly from the online tutorial for making a ray-tracer from scratch. A basic way to make a ray-tracer by Caleb Piercy.