added task 05 solution

common/ray.cpp

@@ -1,3 +1,3 @@
 #include "ray.h"
 
-int Ray::rayCount = 0;
+std::atomic<int> Ray::rayCount(0);

common/ray.h

@@ -39,7 +39,7 @@ private:
   int remainingBounces = ICG_RAY_BOUNCES;
 #endif
 
-  static int rayCount;
+  static std::atomic<int> rayCount;
 };
 
 #endif

renderer/kdtreerenderer.cpp

@@ -11,8 +11,33 @@ Texture KDTreeRenderer::renderImage(Scene const &scene, Camera const &camera, in
 
 Texture KDTreeRenderer::renderKDTree(FastScene const &scene, Camera const &camera, int width, int height) {
   Texture image(width, height);
+  float const aspectRatio = static_cast<float>(height) / width;
 
-  // IMPLEMENT ME
+  for (int x = 0; x < image.width(); ++x) {
+    for (int y = 0; y < image.height(); ++y) {
+      Ray ray = camera.createRay((static_cast<float>(x) / width * 2 - 1),
+                                 -(static_cast<float>(y) / height * 2 - 1) * aspectRatio);
+
+      image.setPixelAt(x, y, Color(float(scene.countNodeIntersections(ray)), 0.0f, 0.0f));
+    }
+  }
+
+  // map color to green -> red map
+  float maxVal = -INFINITY;
+  for (int x = 0; x < image.width(); ++x) {
+    for (int y = 0; y < image.height(); ++y) {
+      maxVal = std::max(maxVal, image.getPixelAt(x, y).r);
+    }
+  }
+
+  Color r(1, 0, 0);
+  Color g(0, 1, 0);
+  for (int x = 0; x < image.width(); ++x) {
+    for (int y = 0; y < image.height(); ++y) {
+      float factor = image.getPixelAt(x, y).r / maxVal;
+      image.setPixelAt(x, y, (1.0f - factor) * g + factor * r);
+    }
+  }
 
   return image;
 }

renderer/simplerenderer.cpp

@@ -2,9 +2,25 @@
 #include "renderer/simplerenderer.h"
 #include "scene/scene.h"
 #include <iostream>
+#include <thread>
 #include <chrono>
 #include <iomanip>
 
+void SimpleRenderer::renderThread(const Scene *scene, Camera const *camera, Texture *image, int width, int widthStep, int widthOffset, int height, int heightStep, int heightOffset, std::atomic<int> *k, int const stepSize) {
+  float const aspectRatio = static_cast<float>(height) / width;
+  for (int y = heightOffset; y < height; y += heightStep) {
+    for (int x = widthOffset; x < width; x += widthStep) {
+      Ray ray = camera->createRay((static_cast<float>(x) / width * 2 - 1), -(static_cast<float>(y) / height * 2 - 1) * aspectRatio);
+      image->setPixelAt(x, y, clamped(scene->traceRay(ray)));
+
+      // Super hacky progress bar!
+      if (++*k % stepSize == 0) {
+        std::cout << "=" << std::flush;
+      }
+    }
+  }
+}
+
 Texture SimpleRenderer::renderImage(Scene const &scene, Camera const &camera, int width, int height) {
   Texture image(width, height);
 
@@ -22,22 +38,24 @@ Texture SimpleRenderer::renderImage(Scene const &scene, Camera const &camera, in
   for (int i = 0; i < barSize - 3 - 5; ++i)
     std::cout << " ";
   std::cout << "100% |" << std::endl << "|";
-  int k = 0;
+  std::atomic<int> k(0);
 
   // Start timer
   start = std::chrono::steady_clock::now();
 
-  float const aspectRatio = static_cast<float>(height) / width;
-  for (int x = 0; x < image.width(); ++x) {
-    for (int y = 0; y < image.height(); ++y) {
-      Ray ray = camera.createRay((static_cast<float>(x) / width * 2 - 1), -(static_cast<float>(y) / height * 2 - 1) * aspectRatio);
-      image.setPixelAt(x, y, clamped(scene.traceRay(ray)));
+  // Spawn a thread for every logical processor -1, calling the renderThread function
+  int const nThreads = std::thread::hardware_concurrency();
+  std::vector<std::thread> threads;
+  for (int t = 0; t < nThreads - 1; ++t) {
+    threads.emplace_back(renderThread, &scene, &camera, &image, width, nThreads, t, height, 1, 0, &k, stepSize);
+  }
 
-      // Super hacky progress bar!
-      if (++k % stepSize == 0) {
-        std::cout << "=" << std::flush;
-      }
-    }
+  // Call the renderThread function yourself
+  renderThread(&scene, &camera, &image, width, nThreads, nThreads - 1, height, 1, 0, &k, stepSize);
+
+  // Rejoin the threads
+  for (int t = 0; t < nThreads - 1; ++t) {
+    threads[t].join();
   }
 
   // Stop timer

renderer/simplerenderer.h

@@ -1,9 +1,13 @@
 #ifndef SIMPLERENDERER_H
 #define SIMPLERENDERER_H
 
+#include <atomic>
 #include "renderer/renderer.h"
 
 class SimpleRenderer : public Renderer {
+  static void renderThread(const Scene *scene, Camera const *camera, Texture *image, int width, int widthStep,
+                           int widthOffset, int height, int heightStep, int heightOffset, std::atomic<int> *k,
+                           int const stepSize);
 
 public:
   // Constructor / Destructor

scene/fastscene.cpp

@@ -5,69 +5,218 @@
 #include <iostream>
 
 int Node::countNodeIntersections(const Ray &ray, float t0, float t1) const {
-  // IMPLEMENT ME
+  // If this is a leaf node, we return 0
+  if (isLeaf()) {
     return 0;
+  } else {
+    // Determine the order in which we intersect the child nodes
+    float const d = (this->split - ray.origin[this->dimension]) / ray.direction[this->dimension];
+    int front = ray.direction[this->dimension] < 0 ? 1 : 0;
+    int back = 1 - front;
+
+    if (d <= t0 || d < 0) {
+      // t0..t1 is totally behind d, only go through the back node.
+      return this->child[back]->countNodeIntersections(ray, t0, t1);
+    } else if (d >= t1) {
+      // t0..t1 is totally in front of d, only go to front node.
+      return this->child[front]->countNodeIntersections(ray, t0, t1);
+    } else {
+      // Traverse *both* children. Front node first, back node last.
+      // Be sure to get even triangles which are coincident with the splitting plane
+      return 1 + this->child[front]->countNodeIntersections(ray, t0, d + SPLT_EPS) + this->child[back]->countNodeIntersections(ray, d - SPLT_EPS, t1);
+    }
+  }
 }
 
 bool Node::findIntersection(Ray &ray, float t0, float t1) const {
-  // IMPLEMENT ME
   // If this is a leaf node, we intersect with all the primitives...
-  // ... otherwise we continue through the branches
+  if (isLeaf()) {
+    bool hit = false;
+    for (const auto &primitive : this->primitives)
+      hit |= primitive->intersect(ray);
+    return hit;
+  } else { // ... otherwise we continue through the branches
+
     // Determine the order in which we intersect the child nodes
-  // Traverse the necessary children
-  return false;
+    float const d = (this->split - ray.origin[this->dimension]) / ray.direction[this->dimension];
+    int front = ray.direction[this->dimension] < 0 ? 1 : 0;
+    int back = 1 - front;
+
+    if (d <= t0 || d < 0) {
+      // t0..t1 is totally behind d, only go through the back node.
+      return this->child[back]->findIntersection(ray, t0, t1);
+    } else if (d >= t1) {
+      // t0..t1 is totally in front of d, only go to front node.
+      return this->child[front]->findIntersection(ray, t0, t1);
+    } else {
+      // Traverse *both* children. Front node first and then back node, if no hit in front of splitting plane.
+      // for whatever reason, this doesn't work in the fireplace scene?!
+      return ((this->child[front]->findIntersection(ray, t0 - SPLT_EPS, d + SPLT_EPS) && ray.length <= d + SPLT_EPS) || this->child[back]->findIntersection(ray, d - SPLT_EPS, t1 + SPLT_EPS));
+      // return (this->child[front]->findIntersection(ray, t0 - SPLT_EPS, d + SPLT_EPS) | this->child[back]->findIntersection(ray, d - SPLT_EPS, t1 + SPLT_EPS));
+    }
+  }
 }
 
 bool Node::findOcclusion(Ray &ray, float t0, float t1) const {
-  // IMPLEMENT ME
+  // If this is a leaf node, we intersect with all the primitives...
+  if (isLeaf()) {
+    float const rayLength = ray.length;
+    for (const auto &primitive : this->primitives)
+      // since this is correct, but terribly slow:...
+      // if (!primitive->shader()->isTransparent() && primitive->intersect(ray))
+      //   return true;
+      // we do it this way:
+      if (primitive->intersect(ray)) {
+        if (!primitive->shader()->isTransparent())
+          return true;
+        else
+          ray.length = rayLength;
+      }
     return false;
+  } else { // ... otherwise we continue through the branches
+
+    // Determine the order in which we intersect the child nodes
+    float const d = (this->split - ray.origin[this->dimension]) / ray.direction[this->dimension];
+    int front = ray.direction[this->dimension] < 0 ? 1 : 0;
+    int back = 1 - front;
+
+    if (d <= t0 || d < 0) {
+      // t0..t1 is totally behind d, only go through the back node.
+      return this->child[back]->findOcclusion(ray, t0, t1);
+    } else if (d >= t1) {
+      // t0..t1 is totally in front of d, only go to front node.
+      return this->child[front]->findOcclusion(ray, t0, t1);
+    } else {
+      // Traverse *both* children. Front node first and then back node, if no hit in front of splitting plane.
+      // for whatever reason, this doesn't work in the fireplace scene?!
+      return ((this->child[front]->findOcclusion(ray, t0, d + SPLT_EPS) && ray.length <= d + SPLT_EPS) || this->child[back]->findOcclusion(ray, d - SPLT_EPS, t1));
+      // return (this->child[front]->findOcclusion(ray, t0, d + SPLT_EPS) | this->child[back]->findOcclusion(ray, d - SPLT_EPS, t1));
+    }
+  }
 }
 
 int FastScene::countNodeIntersections(const Ray &ray) const {
-  // IMPLEMENT ME
+  // Make sure the tree is set up
+  if (!this->root)
     return false;
+
+  // Bounding box intersection
+  Vector3d const min = componentQuotient(this->absoluteMinimum - ray.origin, ray.direction);
+  Vector3d const max = componentQuotient(this->absoluteMaximum - ray.origin, ray.direction);
+  float const tMin = std::max(std::max(std::min(min.x, max.x), std::min(min.y, max.y)), std::min(min.z, max.z));
+  float const tMax = std::min(std::min(std::max(min.x, max.x), std::max(min.y, max.y)), std::max(min.z, max.z));
+
+  // Traverse the tree recursively
+  if (0 <= tMax && tMin <= tMax)
+    return this->root->countNodeIntersections(ray, tMin, tMax);
+  else
+    return 0;
 }
 
 bool FastScene::findIntersection(Ray &ray) const {
-  // IMPLEMENT ME
+  // Make sure the tree is set up
+  if (!this->root)
+    return false;
+
+  // Bounding box intersection
+  Vector3d const min = componentQuotient(this->absoluteMinimum - ray.origin, ray.direction);
+  Vector3d const max = componentQuotient(this->absoluteMaximum - ray.origin, ray.direction);
+  float const tMin = std::max(std::max(std::min(min.x, max.x), std::min(min.y, max.y)), std::min(min.z, max.z));
+  float const tMax = std::min(std::min(std::max(min.x, max.x), std::max(min.y, max.y)), std::max(min.z, max.z));
+
+  // Traverse the tree recursively
+  if (0 <= tMax && tMin <= tMax)
+    return this->root->findIntersection(ray, tMin, tMax);
+  else
     return false;
 }
 
 bool FastScene::findOcclusion(Ray &ray) const {
-  // IMPLEMENT ME
+  // Make sure the tree is set up
+  if (!this->root)
+    return false;
+
+  // Bounding box intersection
+  Vector3d const min = componentQuotient(this->absoluteMinimum - ray.origin, ray.direction);
+  Vector3d const max = componentQuotient(this->absoluteMaximum - ray.origin, ray.direction);
+  float const tMin = std::max(std::max(std::min(min.x, max.x), std::min(min.y, max.y)), std::min(min.z, max.z));
+  float const tMax = std::min(std::min(std::max(min.x, max.x), std::max(min.y, max.y)), std::max(min.z, max.z));
+
+  // Traverse the tree recursively
+  if (0 <= tMax && tMin <= tMax)
+    return this->root->findOcclusion(ray, tMin, tMax);
+  else
     return false;
 }
 
 void FastScene::buildTree(int maximumDepth, int minimumNumberOfPrimitives) {
-  // IMPLEMENT ME
   // Set the new depth and number of primitives
+  this->maximumDepth = maximumDepth;
+  this->minimumNumberOfPrimitives = minimumNumberOfPrimitives;
 
   // Determine the bounding box of the kD-Tree
+  this->absoluteMinimum = Vector3d(+INFINITY, +INFINITY, +INFINITY);
+  this->absoluteMaximum = Vector3d(-INFINITY, -INFINITY, -INFINITY);
+  for (const auto &primitive : this->primitives()) {
+    for (int d = 0; d < 3; ++d) {
+      this->absoluteMinimum[d] = std::min(this->absoluteMinimum[d], primitive->minimumBounds(d));
+      this->absoluteMaximum[d] = std::max(this->absoluteMaximum[d], primitive->maximumBounds(d));
+    }
+  }
 
   // Recursively build the kD-Tree
+  root = this->build(this->absoluteMinimum, this->absoluteMaximum, this->primitives(), 0);
+  std::cout << "(FastScene): " << this->primitives().size() << " primitives organized into tree" << std::endl;
 }
 
 std::unique_ptr<Node> FastScene::build(Vector3d const &minimumBounds, Vector3d const &maximumBounds, const std::vector<std::shared_ptr<Primitive>> &primitives, int depth) {
-  // IMPLEMENT ME
   // Determine the diameter of the bounding box
+  Vector3d const diameter = maximumBounds - minimumBounds;
 
   // Test whether we have reached a leaf node...
+  int minimumDimension = ((diameter.x < diameter.y) ? ((diameter.x < diameter.z) ? 0 : 2) : ((diameter.y < diameter.z) ? 1 : 2));
+  if (depth >= this->maximumDepth || (int)primitives.size() <= this->minimumNumberOfPrimitives || (diameter[minimumDimension]) <= EPSILON) {
+    auto leafNode = std::make_unique<Node>();
+    leafNode->primitives = primitives;
+    return leafNode;
+  }
 
-  // ... otherwise create a new inner node by splitting through the widest
-  // dimension
+  // ... otherwise create a new inner node by splitting through the widest dimension
+  auto node = std::make_unique<Node>();
+  node->dimension = ((diameter.x > diameter.y) ? ((diameter.x > diameter.z) ? 0 : 2) : ((diameter.y > diameter.z) ? 1 : 2));
 
   // Determine the split position
   // Note: Use the median of the minimum bounds of the primitives
+  std::vector<float> minimumValues;
+  for (const auto &primitive : primitives)
+    minimumValues.push_back(primitive->minimumBounds(node->dimension));
+  std::sort(minimumValues.begin(), minimumValues.end());
+  node->split = minimumValues[minimumValues.size() / 2];
 
   // Divide primitives into the left and right lists
   // Remember: A primitive can be in both lists!
   // Also remember: You split exactly at the minimum of a primitive,
   // make sure *that* primitive does *not* appear in both lists!
+  std::vector<std::shared_ptr<Primitive>> leftPrimitives, rightPrimitives;
+  for (const auto &primitive : primitives) {
+    if (primitive->minimumBounds(node->dimension) < node->split)
+      leftPrimitives.push_back(primitive);
+    if (primitive->maximumBounds(node->dimension) >= node->split)
+      rightPrimitives.push_back(primitive);
+  }
 
   // Print out the number of primitives in the left and right child node
+  // std::cout << "(FastScene): Split " << leftPrimitives.size() << " | " << rightPrimitives.size() << std::endl;
 
   // Set the left and right split vectors
+  Vector3d minimumSplit = minimumBounds;
+  Vector3d maximumSplit = maximumBounds;
+  minimumSplit[node->dimension] = node->split;
+  maximumSplit[node->dimension] = node->split;
 
   // Recursively build the tree
-  return nullptr;
+  depth += 1;
+  node->child[0] = this->build(minimumBounds, maximumSplit, leftPrimitives, depth);
+  node->child[1] = this->build(minimumSplit, maximumBounds, rightPrimitives, depth);
+  return node;
 }