Function renderPixelAOShader

tutorials/viewer/viewer_device_debug.cpp:321–387

renders a single pixel with eyelight shading */

/* renders a single pixel with eyelight shading */
Vec3fa renderPixelAOShader(const DebugShaderData& data, float x, float y, const ISPCCamera& camera, RayStats& stats, const RTCFeatureFlags feature_mask)
{
  /* initialize ray */
  Ray ray;
  ray.org = Vec3ff(camera.xfm.p);
  ray.dir = Vec3ff(normalize(x*camera.xfm.l.vx + y*camera.xfm.l.vy + camera.xfm.l.vz));
  ray.tnear() = 0.0f;
  ray.tfar = inf;
  ray.geomID = RTC_INVALID_GEOMETRY_ID;
  ray.primID = RTC_INVALID_GEOMETRY_ID;
  ray.mask = -1;
  ray.time() = data.debug;

  /* intersect ray with scene */
  RTCIntersectArguments args;
  rtcInitIntersectArguments(&args);
  args.feature_mask = feature_mask;
  rtcTraversableIntersect1(data.traversable,RTCRayHit_(ray),&args);
  RayStats_addRay(stats);

  /* shade pixel */
  if (ray.geomID == RTC_INVALID_GEOMETRY_ID) return Vec3fa(0.0f);

  Vec3fa Ng = normalize(ray.Ng);
  Vec3fa Nf = faceforward(Ng,ray.dir,Ng);
  Vec3fa col = Vec3fa(min(1.f,.3f+.8f*abs(dot(Ng,normalize(ray.dir)))));

  /* calculate hit point */
  float intensity = 0;
  Vec3fa hitPos = ray.org + ray.tfar * ray.dir;

#define AMBIENT_OCCLUSION_SAMPLES 64
  /* trace some ambient occlusion rays */
  RandomSampler sampler;
  RandomSampler_init(sampler, (int)x, (int)y, 0);
  for (int i=0; i<AMBIENT_OCCLUSION_SAMPLES; i++)
  {
    Vec2f sample = RandomSampler_get2D(sampler);
    Sample3f dir = cosineSampleHemisphere(sample.x,sample.y,Nf);

    /* initialize shadow ray */
    Ray shadow;
    shadow.org = Vec3ff(hitPos);
    shadow.dir = Vec3ff(dir.v);
    shadow.tnear() = 0.001f;
    shadow.tfar = inf;
    shadow.geomID = RTC_INVALID_GEOMETRY_ID;
    shadow.primID = RTC_INVALID_GEOMETRY_ID;
    shadow.mask = -1;
    shadow.time() = data.debug;

    /* trace shadow ray */
    RTCOccludedArguments args;
    rtcInitOccludedArguments(&args);
    args.feature_mask = feature_mask;
    rtcTraversableOccluded1(data.traversable,RTCRay_(shadow),&args);
    RayStats_addShadowRay(stats);