Replaced Simplex noise with Perlin noise for the 3D and 4D variants of love.math.noise, to avoid patent-infringement issues (resolves issue #997.)

src/libraries/noise1234/noise1234.h

@@ -0,0 +1,57 @@
+// Noise1234
+// Author: Stefan Gustavson (stegu@itn.liu.se)
+//
+// This library is public domain software, released by the author
+// into the public domain in February 2011. You may do anything
+// you like with it. You may even remove all attributions,
+// but of course I'd appreciate it if you kept my name somewhere.
+//
+// This library is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+// General Public License for more details.
+
+/** \file
+		\brief Declares the Noise1234 class for producing Perlin noise.
+		\author Stefan Gustavson (stegu@itn.liu.se)
+*/
+
+/*
+ * This is a clean, fast, modern and free Perlin noise class in C++.
+ * Being a stand-alone class with no external dependencies, it is
+ * highly reusable without source code modifications.
+ *
+ * Note:
+ * Replacing the "float" type with "double" can actually make this run faster
+ * on some platforms. A templatized version of Noise1234 could be useful.
+ */
+
+class Noise1234 {
+
+  public:
+    Noise1234() {}
+    ~Noise1234() {}
+
+/** 1D, 2D, 3D and 4D float Perlin noise, SL "noise()"
+ */
+    static float noise( float x );
+    static float noise( float x, float y );
+    static float noise( float x, float y, float z );
+    static float noise( float x, float y, float z, float w );
+
+/** 1D, 2D, 3D and 4D float Perlin periodic noise, SL "pnoise()"
+ */
+    static float pnoise( float x, int px );
+    static float pnoise( float x, float y, int px, int py );
+    static float pnoise( float x, float y, float z, int px, int py, int pz );
+    static float pnoise( float x, float y, float z, float w,
+                              int px, int py, int pz, int pw );
+
+  private:
+    static unsigned char perm[];
+    static float  grad( int hash, float x );
+    static float  grad( int hash, float x, float y );
+    static float  grad( int hash, float x, float y , float z );
+    static float  grad( int hash, float x, float y, float z, float t );
+
+};