Fitler function for User Defined Geometry

Jianbo_Q_ — Mon, 12 Jun 2017 08:50:02 GMT

Hello everyone,

I meet a problem when setting filter function for a user defined geometry. I searched on the internet and it says I should invoke filter function by myself in the intersect function (https://software.intel.com/en-us/forums/embree-photo-realistic-ray-tracing-kernels/topic/707268). What I want to do is just to collect all the intersected points along a ray.

I don't how this goal is achieved, Is my code correct? Can anybody help me, thank you!

void cellIntersectFunc(void* cell_i, RTCRay& ray, size_t item) {
   cout << "intersect" << endl;
   const Cell* cells = (const Cell*)cell_i;
   const Cell& cell = cells[item];
   Vec3fa dRcp = 1/ray.dir;
   Vec3fa upper_right = cell.left_bottom + Vec3fa(cell.xzExtent, cell.yExtent, cell.xzExtent);
//   int nearAxis = -1, farAxis = -1;
   for (int i = 0; i < 3; i++) {
       const float origin = ray.org;
       const float minVal = cell.left_bottom, maxVal = upper_right;
       if (ray.dir == 0) {//The ray is parallel to the planes.
           if (origin < minVal || origin > maxVal) {
               return;
           }
       }
       else {
           float t1 = (minVal - origin) * dRcp;
           float t2 = (maxVal - origin) * dRcp;
           bool flip = t1 > t2;
           if (flip)
               swap(t1, t2);
           if (t1 > ray.tnear) {
               ray.tfar = t1;
           }
           /*if (t2 < ray.tfar) {
               ray.tfar = t2;
           }*/
       }
   }
   if (!(ray.tnear <= ray.tfar))
       return;
   ray.geomID = cell.geomID;
   ray.primID = (unsigned int)item;
   intersectionFilter(cell_i, ray);
   return;
}

void intersectionFilter(void* ptr, RTCRay& ray_i)
{
   RTCRay2& ray = (RTCRay2&)ray_i;
   ray.hit_geomIDs[ray.lastHit] = ray.geomID;
   ray.lastHit++;
   ray.geomID = RTC_INVALID_GEOMETRY_ID;
   ray.primID = RTC_INVALID_GEOMETRY_ID;
   cout << "hello" << endl;
}

Code looks good to me. What

SvenW_Intel — Tue, 13 Jun 2017 04:34:40 GMT

Code looks good to me. What is the problem with that code?

At the first intersection, it

Jianbo_Q_ — Tue, 13 Jun 2017 13:07:34 GMT

At the first intersection, it works. but I have set geomID to invalid in my filter function. But the ray does not go further. There is no second intersection. But I am sure there should be. So I am not very sure whether there are some problems about how to invoke this function.

Ok I found the issue. You

SvenW_Intel — Wed, 14 Jun 2017 05:30:21 GMT

Ok I found the issue. You should not update any information in the ray if you reject the hit. Just do not change the ray at all and your code will work.

Thank you very much. I tested

Jianbo_Q_ — Tue, 20 Jun 2017 14:28:19 GMT

Thank you very much. I tested your comments, it works. Another solution is to set ray.tfar = inf in the filter function.

topic Ok I found the issue. You in Intel® Embree Ray Tracing Kernels

Fitler function for User Defined Geometry

Code looks good to me. What

At the first intersection, it

Ok I found the issue. You

Thank you very much. I tested