And CSG! \o/

Still working on a nice scene for it.

source/shapes/csg.cpp

@@ -0,0 +1,133 @@
+/*
+ *  DoRayMe - a quick and dirty Raytracer
+ *  Constructive Solid Geometry (CSG) implementation
+ *
+ *  Created by Manoël Trapier
+ *  Copyright (c) 2020 986-Studio.
+ *
+ */
+#include <tuple.h>
+#include <ray.h>
+#include <shape.h>
+#include <csg.h>
+#include <math_helper.h>
+
+
+CSG::CSG(OperationType operation, Shape *left, Shape *right) : Shape(SHAPE_CSG), operation(operation), left(left), right(right)
+{
+    stats.addCsg();
+
+    this->left->parent = this;
+    this->right->parent = this;
+
+    this->bounds | this->left->getBounds();
+    this->bounds | this->right->getBounds();
+}
+
+Intersect CSG::localIntersect(Ray r)
+{
+    int i;
+    Intersect leftxs = this->left->intersect(r);
+    Intersect rightxs = this->right->intersect(r);
+
+    for(i = 0; i < rightxs.count(); i++)
+    {
+        leftxs.add(rightxs[i]);
+    }
+
+    Intersect ret = this->filterIntersections(leftxs);
+
+    return ret;
+}
+
+Tuple CSG::localNormalAt(Tuple point, Intersection *hit)
+{
+    return Vector(1, 0, 0);
+}
+
+BoundingBox CSG::getLocalBounds()
+{
+    return this->bounds;
+}
+
+BoundingBox CSG::getBounds()
+{
+    if (this->bounds.isEmpty()) { this->updateBoundingBox(); }
+    return this->bounds;
+}
+
+void CSG::updateBoundingBox()
+{
+    this->bounds.reset();
+
+    this->bounds | this->left->getBounds();
+    this->bounds | this->right->getBounds();
+}
+
+void CSG::updateTransform()
+{
+    Shape::updateTransform();
+
+    this->left->updateTransform();
+    this->right->updateTransform();
+
+    /* Once the full stack being notified of the changes, let's update the
+     * bounding box
+     */
+    this->updateBoundingBox();
+}
+
+bool CSG::includes(Shape *b)
+{
+    if (this->left->includes(b)) { return true; }
+    if (this->right->includes(b)) { return true; }
+    if (this == b) { return true; }
+    return false;
+}
+
+bool CSG::intersectionAllowed(bool leftHit, bool inLeft, bool inRight)
+{
+    switch(this->operation)
+    {
+    case CSG::UNION:        return (leftHit && !inRight) || (!leftHit && !inLeft);
+    case CSG::INTERSECTION: return (!leftHit && inLeft) || (leftHit && inRight);
+    case CSG::DIFFERENCE:   return (leftHit && !inRight) || (!leftHit && inLeft);
+    }
+    return false;
+}
+
+Intersect CSG::filterIntersections(Intersect &xs)
+{
+    bool inl = false;
+    bool inr = false;
+
+    Intersect ret = Intersect();
+
+    int i;
+
+    for(i = 0; i < xs.count(); i++)
+    {
+        bool lhit = this->left->includes(xs[i].object);
+
+        if (this->intersectionAllowed(lhit, inl, inr))
+        {
+            ret.add(xs[i]);
+        }
+
+        if (lhit)
+        {
+            inl = !inl;
+        }
+        else
+        {
+            inr = !inr;
+        }
+    }
+
+    return ret;
+}
+
+void CSG::dumpMe(FILE *fp)
+{
+
+}