From 2adb782b24f76160c9aedcc52cc8dce93b3dbe52 Mon Sep 17 00:00:00 2001
From: Josh Holtrop <jholtrop+git@gmail.com>
Date: Tue, 20 Jan 2009 04:02:10 +0000
Subject: [PATCH] updated Makefile, tests.cc, util/Matrix

git-svn-id: svn://anubis/fart/trunk@16 7f9b0f55-74a9-4bce-be96-3c2cd072584d
---
 Makefile       |  1 +
 test/tests.cc  | 21 +++++++++++++++++++++
 util/Matrix.cc | 24 +++++++++++++++++++++++-
 util/Matrix.h  |  1 +
 4 files changed, 46 insertions(+), 1 deletion(-)

diff --git a/Makefile b/Makefile
index d68ff37..506dedb 100644
--- a/Makefile
+++ b/Makefile
@@ -15,6 +15,7 @@ $(TARGET):
 	make -C main
 	$(CXX) -o $@ main/*.o util/*.o shapes/*.o $(CXXFLAGS) $(LDFLAGS)
 
+.PHONY: tests
 tests:
 	make -C test
 	$(CXX) -o $@ test/*.o util/*.o shapes/*.o $(CXXFLAGS) $(LDFLAGS)
diff --git a/test/tests.cc b/test/tests.cc
index ed070d3..f7ec3bb 100644
--- a/test/tests.cc
+++ b/test/tests.cc
@@ -1,8 +1,29 @@
 
 #include <iostream>
 #include <cassert>
+#include "util/Matrix.h"
 using namespace std;
 
 int main()
 {
+    Matrix m;
+    int v = 1;
+    for (int i = 0; i < 4; i++)
+    {
+        for (int j = 0; j < 4; j++)
+        {
+            m[i][j] = v++;
+        }
+    }
+
+    cout << "m:" << endl << m;
+
+    Matrix i = m.getInverse();
+
+    cout << "i:" << endl << i;
+
+    Matrix mult = m * i;
+    cout << "mult:" << endl << mult;
+
+    return 0;
 }
diff --git a/util/Matrix.cc b/util/Matrix.cc
index aaa0d98..1303870 100644
--- a/util/Matrix.cc
+++ b/util/Matrix.cc
@@ -59,6 +59,8 @@ double Matrix::determinant()
 
 void Matrix::calculateInverse()
 {
+    if (m_inverse_calculated)
+        return;
     m_inverse_calculated = true;
     m_inverse_valid = false;
     double det = determinant();
@@ -170,6 +172,23 @@ void Matrix::calculateInverse()
     m_inverse_valid = true;
 }
 
+Matrix Matrix::getInverse()
+{
+    calculateInverse();
+    Matrix m;
+    for (int i = 0; i < 4; i++)
+    {
+        for (int j = 0; j < 4; j++)
+        {
+            m.m_matrix[i][j] = m_inverse[i][j];
+            m.m_inverse[i][j] = m_matrix[i][j];
+        }
+    }
+    m.m_inverse_calculated = true;
+    m.m_inverse_valid = m_inverse_valid;
+    return m;
+}
+
 Matrix operator*(const Matrix & m1, const Matrix & m2)
 {
     Matrix res;
@@ -225,7 +244,10 @@ std::ostream & operator<<(std::ostream & out, const Matrix & m)
             if (j < 3)
                 out << ", ";
         }
-        out << "]" << std::endl;
+        out << "]";
+        if (i == 3)
+            out << " ]";
+        out << std::endl;
     }
     return out;
 }
diff --git a/util/Matrix.h b/util/Matrix.h
index 5b42019..964aea2 100644
--- a/util/Matrix.h
+++ b/util/Matrix.h
@@ -14,6 +14,7 @@ class Matrix
         const Matrix_row_t & operator[](int idx) const { return m_matrix[idx]; }
         static Matrix identity();
         double determinant();
+        Matrix getInverse();
 
     protected:
         double m_matrix[4][4];