From 29e8cfd4a72c248583ea9482864c016bb20f40f8 Mon Sep 17 00:00:00 2001
From: Daniel Karbach <daniel.karbach@localhorst.tv>
Date: Thu, 10 Nov 2016 12:49:21 +0100
Subject: [PATCH] test stability of worley noise generator

---
 tst/rand/StabilityTest.cpp | 35 +++++++++++++++++++++++++++++++++++
 tst/rand/StabilityTest.hpp |  8 ++++++++
 2 files changed, 43 insertions(+)

diff --git a/tst/rand/StabilityTest.cpp b/tst/rand/StabilityTest.cpp
index 5794337..4aab3eb 100644
--- a/tst/rand/StabilityTest.cpp
+++ b/tst/rand/StabilityTest.cpp
@@ -2,6 +2,7 @@
 
 #include "rand/GaloisLFSR.hpp"
 #include "rand/SimplexNoise.hpp"
+#include "rand/WorleyNoise.hpp"
 
 #include <cstdint>
 #include <string>
@@ -251,6 +252,27 @@ void StabilityTest::testSimplex() {
 	Assert(noise, glm::vec3(-1.0f, -1.0f, -1.0f),  0.0f);
 }
 
+void StabilityTest::testWorley() {
+	WorleyNoise noise(0);
+
+	Assert(noise, glm::vec3(0.0f, 0.0f, 0.0f), -0.117765009403229f);
+	Assert(noise, glm::vec3(0.0f, 0.0f, 1.0f), -0.209876894950867f);
+	Assert(noise, glm::vec3(0.0f, 1.0f, 0.0f), -0.290086328983307f);
+	Assert(noise, glm::vec3(0.0f, 1.0f, 1.0f), -0.332393705844879f);
+	Assert(noise, glm::vec3(1.0f, 0.0f, 0.0f), -0.621925830841064f);
+	Assert(noise, glm::vec3(1.0f, 0.0f, 1.0f), -0.338455379009247f);
+	Assert(noise, glm::vec3(1.0f, 1.0f, 0.0f), -0.386664032936096f);
+	Assert(noise, glm::vec3(1.0f, 1.0f, 1.0f), -0.533940434455872f);
+
+	Assert(noise, glm::vec3( 0.0f,  0.0f, -1.0f), -0.425480604171753f);
+	Assert(noise, glm::vec3( 0.0f, -1.0f,  0.0f), -0.189745843410492f);
+	Assert(noise, glm::vec3( 0.0f, -1.0f, -1.0f), -0.30408102273941f);
+	Assert(noise, glm::vec3(-1.0f,  0.0f,  0.0f), -0.618566155433655f);
+	Assert(noise, glm::vec3(-1.0f,  0.0f, -1.0f), -0.060045599937439f);
+	Assert(noise, glm::vec3(-1.0f, -1.0f,  0.0f), -0.366827547550201f);
+	Assert(noise, glm::vec3(-1.0f, -1.0f, -1.0f), -0.575981974601746f);
+}
+
 void StabilityTest::Assert(
 	const SimplexNoise &noise,
 	const glm::vec3 &position,
@@ -264,5 +286,18 @@ void StabilityTest::Assert(
 	);
 }
 
+void StabilityTest::Assert(
+	const WorleyNoise &noise,
+	const glm::vec3 &position,
+	float expected
+) {
+	stringstream msg;
+	msg << "unexpected worley noise value at " << position;
+	CPPUNIT_ASSERT_DOUBLES_EQUAL_MESSAGE(
+		msg.str(),
+		expected, noise(position), numeric_limits<float>::epsilon()
+	);
+}
+
 }
 }
diff --git a/tst/rand/StabilityTest.hpp b/tst/rand/StabilityTest.hpp
index b2ee1ae..acc6741 100644
--- a/tst/rand/StabilityTest.hpp
+++ b/tst/rand/StabilityTest.hpp
@@ -10,6 +10,7 @@
 namespace blank {
 
 class SimplexNoise;
+class WorleyNoise;
 
 namespace test {
 
@@ -20,6 +21,7 @@ CPPUNIT_TEST_SUITE(StabilityTest);
 
 CPPUNIT_TEST(testRNG);
 CPPUNIT_TEST(testSimplex);
+CPPUNIT_TEST(testWorley);
 
 CPPUNIT_TEST_SUITE_END();
 
@@ -29,12 +31,18 @@ public:
 
 	void testRNG();
 	void testSimplex();
+	void testWorley();
 
 	static void Assert(
 		const SimplexNoise &noise,
 		const glm::vec3 &position,
 		float expected);
 
+	static void Assert(
+		const WorleyNoise &noise,
+		const glm::vec3 &position,
+		float expected);
+
 };
 
 }
-- 
2.39.2