bool intersect_ray_mesh(const ray & ray, const geometry_mesh & mesh, float * hit_t, int * hit_tri, float2 * hit_uv)
{
float best_t = std::numeric_limits<float>::infinity(), t;
float2 best_uv, uv;
int best_tri = -1;
for(auto & tri : mesh.triangles)
{
if(intersect_ray_triangle(ray, mesh.vertices[tri[0]].position, mesh.vertices[tri[1]].position, mesh.vertices[tri[2]].position, &t, &uv) && t < best_t)
{
best_t = t;
best_uv = uv;
best_tri = &tri - mesh.triangles.data();
}
}
if(best_tri == -1) return false;
if(hit_t) *hit_t = best_t;
if(hit_tri) *hit_tri = best_tri;
if(hit_uv) *hit_uv = best_uv;
return true;
}
Intersection *intersect_ray_glm_object(Ray *ray, GLMmodel *model)
{
static GLMgroup* group;
static GLMtriangle* triangle;
Vect V0, V1, V2;
Intersection *nearest_inter = NULL;
Intersection *inter = NULL;
// iterate over all groups in the model
for (group = model->groups; group; group = group->next) {
// iterate over all triangles in this group
for (int i = 0; i < group->numtriangles; i++) {
triangle = &model->triangles[group->triangles[i]];
// get triangle vertices
V0[X] = model->vertices[3 * triangle->vindices[0]];
V0[Y] = model->vertices[3 * triangle->vindices[0] + 1];
V0[Z] = model->vertices[3 * triangle->vindices[0] + 2];
V1[X] = model->vertices[3 * triangle->vindices[1]];
V1[Y] = model->vertices[3 * triangle->vindices[1] + 1];
V1[Z] = model->vertices[3 * triangle->vindices[1] + 2];
V2[X] = model->vertices[3 * triangle->vindices[2]];
V2[Y] = model->vertices[3 * triangle->vindices[2] + 1];
V2[Z] = model->vertices[3 * triangle->vindices[2] + 2];
// test for intersection
inter = intersect_ray_triangle(ray, V0, V1, V2);
// we have a hit in front of the camera...
if (inter) {
// set normal
inter->N[X] = model->facetnorms[3 * triangle->findex];
inter->N[Y] = model->facetnorms[3 * triangle->findex + 1];
inter->N[Z] = model->facetnorms[3 * triangle->findex + 2];
inter->surf = model_surf_list[model->index];
//MY CODE
inter->objP[0] = model->position[0];
inter->objP[1] = model->position[1];
inter->objP[2] = model->position[2];
inter->model = model;
// this the first hit
if (!nearest_inter) {
nearest_inter = inter;
}
// this is closer than any previous hit
else if (inter->t < nearest_inter->t) {
free(nearest_inter);
nearest_inter = inter;
}
// something else is closer--move along
else {
free(inter);
}
}
}
}
return nearest_inter;
}
