checkpoint

[anneal.git] / src / edu / berkeley / qfat / geom / Matrix.java

diff --git a/src/edu/berkeley/qfat/geom/Matrix.java b/src/edu/berkeley/qfat/geom/Matrix.java
index a00eb4a..dbe4076 100644 (file)
--- a/src/edu/berkeley/qfat/geom/Matrix.java
+++ b/src/edu/berkeley/qfat/geom/Matrix.java
@@ -16,10 +16,13 @@ public class Matrix {
     public final float a, b, c, d, e, f, g, h, i, j, k, l, m, n, o, p;
 
     /** the zero matrix */
-    public static final Matrix ZERO = new Matrix(0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0);
+    public static final Matrix ZERO          = new Matrix(0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0);
 
     /** the identity matrix */
-    public static final Matrix ONE  = new Matrix(1,0,0,0,0,1,0,0,0,0,1,0,0,0,0,1);
+    public static final Matrix ONE           = new Matrix(1,0,0,0,0,1,0,0,0,0,1,0,0,0,0,1);
+
+    /** the identity matrix */
+    public static final Matrix NEGATIVE_ONE  = new Matrix(-1,0,0,0,0,-1,0,0,0,0,-1,0,0,0,0,1);
 
     public Matrix(float a, float b, float c, float d, float e, float f, float g,
                   float h, float i, float j, float k, float l, float m, float n, float o, float p) {
@@ -222,4 +225,56 @@ public class Matrix {
             .times(1/determinant);
     }
 
+    public String toString() {
+        return
+            "\n [ " + a + "\t" + b + "\t" + c + "\t" + d + "\t" + "]" + 
+            "\n [ " + e + "\t" + f + "\t" + g + "\t" + h + "\t" + "]" + 
+            "\n [ " + i + "\t" + j + "\t" + k + "\t" + l + "\t" + "]" + 
+            "\n [ " + m + "\t" + n + "\t" + o + "\t" + p + "\t" + "]\n";
+    }
+
+    public boolean equals(Object oo) {
+        if (oo==null) return false;
+        if (!(oo instanceof Matrix)) return false;
+        Matrix z = (Matrix)oo;
+        return
+            near(a,z.a) && 
+            near(b,z.b) && 
+            near(c,z.c) && 
+            near(d,z.d) && 
+            near(e,z.e) && 
+            near(f,z.f) && 
+            near(g,z.g) && 
+            near(h,z.h) && 
+            near(i,z.i) && 
+            near(j,z.j) && 
+            near(k,z.k) && 
+            near(l,z.l) && 
+            near(m,z.m) && 
+            near(n,z.n) && 
+            near(o,z.o) && 
+            near(p,z.p);
+    }
+    private static final float EPSILON = 0.001f;
+    private static boolean near(float a, float b) { return Math.abs(a-b)<EPSILON; }
+
+    public int hashCode() {
+        return
+            Float.floatToIntBits(a) ^
+            Float.floatToIntBits(b) ^
+            Float.floatToIntBits(c) ^
+            Float.floatToIntBits(d) ^
+            Float.floatToIntBits(e) ^
+            Float.floatToIntBits(f) ^
+            Float.floatToIntBits(g) ^
+            Float.floatToIntBits(h) ^
+            Float.floatToIntBits(i) ^
+            Float.floatToIntBits(j) ^
+            Float.floatToIntBits(k) ^
+            Float.floatToIntBits(l) ^
+            Float.floatToIntBits(m) ^
+            Float.floatToIntBits(n) ^
+            Float.floatToIntBits(o) ^
+            Float.floatToIntBits(p);
+    }
 }