From 3d53ee5eb1cc5ed1dfb25de660c4ce7490c97823 Mon Sep 17 00:00:00 2001
From: Danny Robson <danny@nerdcruft.net>
Date: Tue, 3 Feb 2015 12:53:41 +1100
Subject: [PATCH] bezier: add region query

---
 bezier.cpp      | 30 ++++++++++++++++++++++++++++++
 bezier.hpp      |  3 +++
 test/bezier.cpp | 44 ++++++++++++++++++++++++++++++++++++++++++++
 3 files changed, 77 insertions(+)

diff --git a/bezier.cpp b/bezier.cpp
index 5e85f344..510ce872 100644
--- a/bezier.cpp
+++ b/bezier.cpp
@@ -359,6 +359,36 @@ namespace util {
 }
 
 
+//-----------------------------------------------------------------------------
+template <size_t S>
+util::region2f
+util::bezier<S>::region (void) const
+{
+    util::region2f r;
+
+    float x0 = m_points[0].x;
+    float y0 = m_points[0].y;
+
+    float x1 = x0;
+    float y1 = y0;
+
+    for (size_t i = 1; i < S+1; ++i) {
+        x0 = min (x0, m_points[i].x);
+        y0 = min (y0, m_points[i].y);
+
+        x1 = max (x1, m_points[i].x);
+        y1 = max (y1, m_points[i].y);
+    }
+
+    return {
+        x0,
+        y0,
+        x1 - x0,
+        y1 - y0
+    };
+}
+
+
 //-----------------------------------------------------------------------------
 template <size_t S>
 util::point2f&
diff --git a/bezier.hpp b/bezier.hpp
index 287a9212..24f073d6 100644
--- a/bezier.hpp
+++ b/bezier.hpp
@@ -21,6 +21,7 @@
 #define __UTIL_BEZIER_HPP
 
 #include "point.hpp"
+#include "region.hpp"
 
 #include <iostream>
 
@@ -40,6 +41,8 @@ namespace util {
 
         float distance (point2f) const;
 
+        region2f region (void) const;
+
         point2f& operator[] (size_t idx);
         const point2f& operator[] (size_t idx) const;
 
diff --git a/test/bezier.cpp b/test/bezier.cpp
index d38af386..0d304c6a 100644
--- a/test/bezier.cpp
+++ b/test/bezier.cpp
@@ -8,6 +8,7 @@
 //-----------------------------------------------------------------------------
 template <size_t> void test_eval (void);
 template <size_t> void test_intersect (void);
+template <size_t> void test_region (void);
 
 
 //-----------------------------------------------------------------------------
@@ -161,6 +162,45 @@ test_intersect<3> (void)
 }
 
 
+//-----------------------------------------------------------------------------
+template <>
+void
+test_region<1> (void)
+{
+    static const util::bezier<1> upright ({{0.f, 0.f}, {100.f, 100.f}});
+    static const util::bezier<1> downleft ({{100.f, 100.f}, {0.f, 0.f}});
+    static const util::bezier<1> vertical ({{0.f, 0.f}, {0.f, 100.f}});
+    static const util::bezier<1> horizontal ({{0.f, 0.f}, {100.f, 0.f}});
+
+    CHECK_EQ (upright.region (), util::region2f (0.f, 0.f, 100.f, 100.f));
+    CHECK_EQ (downleft.region (), util::region2f (0.f, 0.f, 100.f, 100.f));
+    CHECK_EQ (vertical.region (), util::region2f (0.f, 0.f, 0.f, 100.f));
+    CHECK_EQ (horizontal.region (), util::region2f (0.f, 0.f, 100.f, 0.f));
+}
+
+
+//-----------------------------------------------------------------------------
+template <>
+void
+test_region<2> (void)
+{
+    static const util::bezier<2> upright({{0.f, 0.f}, {50.f, 50.f}, {100.f, 100.f}});
+
+    CHECK_EQ (upright.region (), util::region2f (0.0f, 0.f, 100.f, 100.0f));
+}
+
+
+//-----------------------------------------------------------------------------
+template <>
+void
+test_region<3> (void)
+{
+    static const util::bezier<3> upright({{0.f, 0.f}, {33.f, 33.f}, {67.f, 67.f}, {100.f, 100.f}});
+
+    CHECK_EQ (upright.region (), util::region2f (0.0f, 0.f, 100.f, 100.0f));
+}
+
+
 //-----------------------------------------------------------------------------
 int
 main (int, char**)
@@ -173,5 +213,9 @@ main (int, char**)
     test_intersect<2> ();
     test_intersect<3> ();
 
+    test_region<1> ();
+    test_region<2> ();
+    test_region<3> ();
+
     return EXIT_SUCCESS;
 }