Function postIntersectGeometry

tutorials/pathtracer/pathtracer_device.cpp:1108–1341

}

void postIntersectGeometry(const TutorialData& data, const Ray& ray, DifferentialGeometry& dg, ISPCGeometry* geometry, int& materialID)
{
  if (geometry->type == TRIANGLE_MESH)
  {
    ISPCTriangleMesh* mesh = (ISPCTriangleMesh*) geometry;
    materialID = mesh->geom.materialID;

    ISPCTriangle* tri = &mesh->triangles[dg.primID];
    const Vec3fa p0 = Vec3fa(mesh->positions[0][tri->v0]);
    const Vec3fa p1 = Vec3fa(mesh->positions[0][tri->v1]);
    const Vec3fa p2 = Vec3fa(mesh->positions[0][tri->v2]);
    const Vec3fa e = max(max(abs(p0),abs(p1)),max(abs(p2),abs(ray.org)));
    dg.eps = 32.0f*1.19209e-07f*max(max(e.x,e.y),max(e.z,ray.tfar));
    
    if (mesh->texcoords)
    {
      ISPCTriangle* tri = &mesh->triangles[dg.primID];
      const Vec2f st0 = mesh->texcoords[tri->v0];
      const Vec2f st1 = mesh->texcoords[tri->v1];
      const Vec2f st2 = mesh->texcoords[tri->v2];
      const float u = ray.u, v = ray.v, w = 1.0f-ray.u-ray.v;
      const Vec2f st = w*st0 + u*st1 + v*st2;
      dg.u = st.x;
      dg.v = st.y;
    }
    if (mesh->normals)
    {
      if (mesh->numTimeSteps == 1)
      {
        ISPCTriangle* tri = &mesh->triangles[dg.primID];
        const Vec3fa n0 = Vec3fa(mesh->normals[0][tri->v0]);
        const Vec3fa n1 = Vec3fa(mesh->normals[0][tri->v1]);
        const Vec3fa n2 = Vec3fa(mesh->normals[0][tri->v2]);
        const float u = ray.u, v = ray.v, w = 1.0f-ray.u-ray.v;
        dg.Ns = w*n0 + u*n1 + v*n2;
      }
      else
      {
        ISPCTriangle* tri = &mesh->triangles[dg.primID];
        float f = mesh->numTimeSteps*ray.time();
        int itime = clamp((int)floor(f),0,(int)mesh->numTimeSteps-2);
        float t1 = f-itime;
        float t0 = 1.0f-t1;
        const Vec3fa a0 = Vec3fa(mesh->normals[itime+0][tri->v0]);
        const Vec3fa a1 = Vec3fa(mesh->normals[itime+0][tri->v1]);
        const Vec3fa a2 = Vec3fa(mesh->normals[itime+0][tri->v2]);
        const Vec3fa b0 = Vec3fa(mesh->normals[itime+1][tri->v0]);
        const Vec3fa b1 = Vec3fa(mesh->normals[itime+1][tri->v1]);
        const Vec3fa b2 = Vec3fa(mesh->normals[itime+1][tri->v2]);
        const Vec3fa n0 = t0*a0 + t1*b0;
        const Vec3fa n1 = t0*a1 + t1*b1;
        const Vec3fa n2 = t0*a2 + t1*b2;
        const float u = ray.u, v = ray.v, w = 1.0f-ray.u-ray.v;
        dg.Ns = w*n0 + u*n1 + v*n2;
      }
    }
  }
  else if (geometry->type == QUAD_MESH)