From 27cea5e70242c85439c07592ebea743fae148ec4 Mon Sep 17 00:00:00 2001
From: Josh Holtrop <jholtrop+git@gmail.com>
Date: Fri, 27 Feb 2009 18:34:08 +0000
Subject: [PATCH] added Union shape based on Intersect

git-svn-id: svn://anubis/fart/trunk@156 7f9b0f55-74a9-4bce-be96-3c2cd072584d
---
 shapes/Intersect.cc |  1 -
 shapes/Union.cc     | 67 +++++++++++++++++++++++++++++++++++++++++++++
 shapes/Union.h      | 20 ++++++++++++++
 3 files changed, 87 insertions(+), 1 deletion(-)
 create mode 100644 shapes/Union.cc
 create mode 100644 shapes/Union.h

diff --git a/shapes/Intersect.cc b/shapes/Intersect.cc
index 9ad50c8..f142771 100644
--- a/shapes/Intersect.cc
+++ b/shapes/Intersect.cc
@@ -19,7 +19,6 @@ Shape::IntersectionList Intersect::intersect(refptr<Shape> _this, const Ray & ra
     bool in1 = false, in2 = false;
     bool in_bool = false;
 
-    /* TODO: finish */
     for (int i = 0, sz = merged.size(); i < sz; i++)
     {
         Vector normal = merged[i].intersection.shape->getNormalAt(
diff --git a/shapes/Union.cc b/shapes/Union.cc
new file mode 100644
index 0000000..4f1eca4
--- /dev/null
+++ b/shapes/Union.cc
@@ -0,0 +1,67 @@
+
+#include "Union.h"
+#include <iostream>
+using namespace std;
+
+Union::Union(refptr<Shape> shape1, refptr<Shape> shape2)
+{
+    m_shape1 = shape1;
+    m_shape2 = shape2;
+}
+
+Shape::IntersectionList Union::intersect(refptr<Shape> _this, const Ray & ray)
+{
+    IntersectionList res1 = m_shape1->intersect(m_shape1, ray);
+    IntersectionList res2 = m_shape2->intersect(m_shape2, ray);
+    BoolIntersectionList merged(res1, res2, ray.getOrigin());
+
+    IntersectionList res;
+    bool in1 = false, in2 = false;
+    bool in_bool = false;
+
+    /* TODO: finish */
+    for (int i = 0, sz = merged.size(); i < sz; i++)
+    {
+        Vector normal = merged[i].intersection.shape->getNormalAt(
+                            merged[i].intersection.vector);
+        double dot = - (ray.getDirection() % normal);
+        bool front = dot > 0.0;
+        bool left = merged[i].left;
+        if (front)
+        {
+            if (left)
+                in1 = true;
+            else
+                in2 = true;
+            if (!in_bool && in1 && in2)
+            {
+                /* we found an intersection point with the boolean object */
+                in_bool = true;
+                res.add( merged[i].intersection );
+            }
+        }
+        else
+        {
+            if (in_bool && in1 && in2)
+            {
+                /* we found an intersection point with the boolean object */
+                res.add( merged[i].intersection );
+            }
+            if (left)
+                in1 = false;
+            else
+                in2 = false;
+            in_bool = false;
+        }
+    }
+
+    return res;
+}
+
+Vector Union::getNormalAt(const Vector & pt)
+{
+    /* this should not be called */
+    cerr << __FILE__ << ": " << __LINE__ <<
+        ": error: Union::getNormalAt() was called!" << endl;
+    return Vector(0, 0, 0);
+}
diff --git a/shapes/Union.h b/shapes/Union.h
new file mode 100644
index 0000000..bf9a9fb
--- /dev/null
+++ b/shapes/Union.h
@@ -0,0 +1,20 @@
+
+#ifndef UNION_H
+#define UNION_H UNION_H
+
+#include "Shape.h"
+
+class Union : public Shape
+{
+    public:
+        Union(refptr<Shape> shape1, refptr<Shape> shape2);
+        IntersectionList intersect(refptr<Shape> _this, const Ray & ray);
+        Vector getNormalAt(const Vector & pt);
+
+    protected:
+        refptr<Shape> m_shape1;
+        refptr<Shape> m_shape2;
+};
+
+#endif
+