Move PRNG to Random.hh

Terrain.xcodeproj/project.pbxproj

@@ -51,6 +51,7 @@
 		C018AD3F21978E690094BE3C /* Queue.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = Queue.swift; sourceTree = "<group>"; };
 		C018AD412197907B0094BE3C /* QueueTests.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = QueueTests.swift; sourceTree = "<group>"; };
 		C028A6A121A46796005DE718 /* Math.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = Math.swift; sourceTree = "<group>"; };
+		C04A27A421A6FB4B00FCABFB /* Random.hh */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.cpp.h; path = Random.hh; sourceTree = "<group>"; };
 		C08C589F218F46F000EAFC2D /* Algorithms.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = Algorithms.swift; sourceTree = "<group>"; };
 		C08C58A1218F474E00EAFC2D /* TerrainAlgorithms.metal */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.metal; path = TerrainAlgorithms.metal; sourceTree = "<group>"; };
 		C0C15A8A218DDD85007494E2 /* Terrain.app */ = {isa = PBXFileReference; explicitFileType = wrapper.application; includeInIndex = 0; path = Terrain.app; sourceTree = BUILT_PRODUCTS_DIR; };
@@ -121,6 +122,7 @@
 			isa = PBXGroup;
 			children = (
 				C0C15ABA218E2A90007494E2 /* ShaderTypes.h */,
+				C04A27A421A6FB4B00FCABFB /* Random.hh */,
 				C0C15AB8218E2A90007494E2 /* Shaders.metal */,
 				C08C58A1218F474E00EAFC2D /* TerrainAlgorithms.metal */,
 			);

Terrain2/Shaders/Random.hh

@@ -0,0 +1,44 @@
+//
+//  Random.hh
+//  Terrain
+//
+//  Created by Eryn Wells on 11/22/18.
+//  Copyright © 2018 Eryn Wells. All rights reserved.
+//
+
+#ifndef Random_hh
+#define Random_hh
+
+/// A pseudo-random number generator providing several algorithms.
+/// - http://reedbeta.com/blog/quick-and-easy-gpu-random-numbers-in-d3d11/
+struct PRNG {
+    PRNG(uint seed) : mSeed(wangHash(seed)) { }
+
+    /// Generate a random unsigned integer using a linear congruential generator.
+    uint lcg() {
+        mSeed = 1664525 * mSeed + 1013904223;
+        return mSeed;
+    }
+
+    /// Generate a random unsigned integer using the Xorshift algorithm from George Marsaglia's paper.
+    uint xorShift() {
+        mSeed ^= (mSeed << 13);
+        mSeed ^= (mSeed >> 17);
+        mSeed ^= (mSeed << 5);
+        return mSeed;
+    }
+
+    uint wangHash(uint seed) {
+        seed = (seed ^ 61) ^ (seed >> 16);
+        seed *= 9;
+        seed = seed ^ (seed >> 4);
+        seed *= 0x27d4eb2d;
+        seed = seed ^ (seed >> 15);
+        return seed;
+    }
+
+    private:
+    uint mSeed;
+};
+
+#endif /* Random_hh */

Terrain2/Shaders/TerrainAlgorithms.metal

@@ -9,40 +9,10 @@
 #include <metal_stdlib>
 #include <metal_types>
 #include "ShaderTypes.h"
+#include "Random.hh"
+
 using namespace metal;
 
-/// A pseudo-random number generator providing several algorithms.
-/// - http://reedbeta.com/blog/quick-and-easy-gpu-random-numbers-in-d3d11/
-struct PRNG {
-    PRNG(uint seed) : mSeed(wangHash(seed)) { }
-
-    /// Generate a random unsigned integer using a linear congruential generator.
-    uint lcg() {
-        mSeed = 1664525 * mSeed + 1013904223;
-        return mSeed;
-    }
-
-    /// Generate a random unsigned integer using the Xorshift algorithm from George Marsaglia's paper.
-    uint xorShift() {
-        mSeed ^= (mSeed << 13);
-        mSeed ^= (mSeed >> 17);
-        mSeed ^= (mSeed << 5);
-        return mSeed;
-    }
-
-    uint wangHash(uint seed) {
-        seed = (seed ^ 61) ^ (seed >> 16);
-        seed *= 9;
-        seed = seed ^ (seed >> 4);
-        seed *= 0x27d4eb2d;
-        seed = seed ^ (seed >> 15);
-        return seed;
-    }
-
-private:
-    uint mSeed;
-};
-
 kernel void updateGeometryHeights(texture2d<float> texture [[texture(GeneratorTextureIndexIn)]],
                                   constant float2 *texCoords [[buffer(GeneratorBufferIndexTexCoords)]],
                                   constant Uniforms &uniforms [[buffer(GeneratorBufferIndexUniforms)]],