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-rw-r--r--Tools/NoiseSpeedTest/CMakeLists.txt66
-rw-r--r--Tools/NoiseSpeedTest/Globals.cpp10
-rw-r--r--Tools/NoiseSpeedTest/Globals.h243
-rw-r--r--Tools/NoiseSpeedTest/NoiseSpeedTest.cpp149
-rw-r--r--Tools/NoiseSpeedTest/NoiseSpeedTest.h5
-rw-r--r--Tools/NoiseSpeedTest/SimplexNoise.h263
6 files changed, 736 insertions, 0 deletions
diff --git a/Tools/NoiseSpeedTest/CMakeLists.txt b/Tools/NoiseSpeedTest/CMakeLists.txt
new file mode 100644
index 000000000..29163398b
--- /dev/null
+++ b/Tools/NoiseSpeedTest/CMakeLists.txt
@@ -0,0 +1,66 @@
+project (NoiseSpeedTest)
+
+include(../../SetFlags.cmake)
+set_flags()
+set_lib_flags()
+enable_profile()
+
+# Set include paths to the used libraries:
+include_directories(SYSTEM "../../lib")
+include_directories("../../src")
+
+set_exe_flags()
+
+# Include the shared files:
+set(SHARED_SRC
+ ../../src/Logger.cpp
+ ../../src/LoggerListeners.cpp
+ ../../src/OSSupport/CriticalSection.cpp
+ ../../src/OSSupport/File.cpp
+ ../../src/OSSupport/StackTrace.cpp
+ ../../src/Noise/Noise.cpp
+ ../../src/StringUtils.cpp
+)
+set(SHARED_HDR
+ ../../src/Noise/Noise.h
+ ../../src/Noise/OctavedNoise.h
+ ../../src/Noise/RidgedNoise.h
+ ../../src/OSSupport/CriticalSection.h
+ ../../src/OSSupport/File.h
+ ../../src/OSSupport/StackTrace.h
+ ../../src/StringUtils.h
+)
+
+if(WIN32)
+ list (APPEND SHARED_SRC ../../src/StackWalker.cpp)
+ list (APPEND SHARED_HDR ../../src/StackWalker.h)
+endif()
+
+source_group("Shared" FILES ${SHARED_SRC} ${SHARED_HDR})
+
+
+
+
+# Include the main source files:
+set(SOURCES
+ NoiseSpeedTest.cpp
+ Globals.cpp
+)
+set(HEADERS
+ NoiseSpeedTest.h
+ Globals.h
+)
+
+source_group("" FILES ${SOURCES} ${HEADERS})
+
+add_executable(NoiseSpeedTest
+ ${SOURCES}
+ ${HEADERS}
+ ${SHARED_SRC}
+ ${SHARED_HDR}
+)
+
+set_target_properties(
+ NoiseSpeedTest
+ PROPERTIES FOLDER Tools
+)
diff --git a/Tools/NoiseSpeedTest/Globals.cpp b/Tools/NoiseSpeedTest/Globals.cpp
new file mode 100644
index 000000000..13c6ae709
--- /dev/null
+++ b/Tools/NoiseSpeedTest/Globals.cpp
@@ -0,0 +1,10 @@
+
+// Globals.cpp
+
+// This file is used for precompiled header generation in MSVC environments
+
+#include "Globals.h"
+
+
+
+
diff --git a/Tools/NoiseSpeedTest/Globals.h b/Tools/NoiseSpeedTest/Globals.h
new file mode 100644
index 000000000..ed9ef82fe
--- /dev/null
+++ b/Tools/NoiseSpeedTest/Globals.h
@@ -0,0 +1,243 @@
+
+// Globals.h
+
+// This file gets included from every module in the project, so that global symbols may be introduced easily
+// Also used for precompiled header generation in MSVC environments
+
+
+
+
+
+// Compiler-dependent stuff:
+#if defined(_MSC_VER)
+ // MSVC produces warning C4481 on the override keyword usage, so disable the warning altogether
+ #pragma warning(disable:4481)
+
+ // Disable some warnings that we don't care about:
+ #pragma warning(disable:4100)
+
+ #define OBSOLETE __declspec(deprecated)
+
+ // No alignment needed in MSVC
+ #define ALIGN_8
+ #define ALIGN_16
+
+ #define FORMATSTRING(formatIndex, va_argsIndex)
+
+ // MSVC has its own custom version of zu format
+ #define SIZE_T_FMT "%Iu"
+ #define SIZE_T_FMT_PRECISION(x) "%" #x "Iu"
+ #define SIZE_T_FMT_HEX "%Ix"
+
+ #define NORETURN __declspec(noreturn)
+
+#elif defined(__GNUC__)
+
+ // TODO: Can GCC explicitly mark classes as abstract (no instances can be created)?
+ #define abstract
+
+ #define OBSOLETE __attribute__((deprecated))
+
+ #define ALIGN_8 __attribute__((aligned(8)))
+ #define ALIGN_16 __attribute__((aligned(16)))
+
+ // Some portability macros :)
+ #define stricmp strcasecmp
+
+ #define FORMATSTRING(formatIndex,va_argsIndex)
+
+ #define SIZE_T_FMT "%zu"
+ #define SIZE_T_FMT_PRECISION(x) "%" #x "zu"
+ #define SIZE_T_FMT_HEX "%zx"
+
+ #define NORETURN __attribute((__noreturn__))
+#else
+
+ #error "You are using an unsupported compiler, you might need to #define some stuff here for your compiler"
+
+ /*
+ // Copy and uncomment this into another #elif section based on your compiler identification
+
+ // Explicitly mark classes as abstract (no instances can be created)
+ #define abstract
+
+ // Mark functions as obsolete, so that their usage results in a compile-time warning
+ #define OBSOLETE
+
+ // Mark types / variables for alignment. Do the platforms need it?
+ #define ALIGN_8
+ #define ALIGN_16
+ */
+
+ #define FORMATSTRING(formatIndex,va_argsIndex) __attribute__((format (printf, formatIndex, va_argsIndex)))
+
+#endif
+
+
+
+
+
+// Integral types with predefined sizes:
+typedef long long Int64;
+typedef int Int32;
+typedef short Int16;
+
+typedef unsigned long long UInt64;
+typedef unsigned int UInt32;
+typedef unsigned short UInt16;
+
+typedef unsigned char Byte;
+
+
+
+
+
+// A macro to disallow the copy constructor and operator= functions
+// This should be used in the private: declarations for any class that shouldn't allow copying itself
+#define DISALLOW_COPY_AND_ASSIGN(TypeName) \
+ TypeName(const TypeName &); \
+ void operator=(const TypeName &)
+
+// A macro that is used to mark unused function parameters, to avoid pedantic warnings in gcc
+#define UNUSED(X) (void)(X)
+
+
+
+
+// OS-dependent stuff:
+#ifdef _WIN32
+ #define WIN32_LEAN_AND_MEAN
+ #include <Windows.h>
+ #include <winsock2.h>
+ #include <ws2tcpip.h>
+
+ // Windows SDK defines min and max macros, messing up with our std::min and std::max usage
+ #undef min
+ #undef max
+
+ // Windows SDK defines GetFreeSpace as a constant, probably a Win16 API remnant
+ #ifdef GetFreeSpace
+ #undef GetFreeSpace
+ #endif // GetFreeSpace
+
+ #define SocketError WSAGetLastError()
+#else
+ #include <sys/types.h>
+ #include <sys/stat.h> // for mkdir
+ #include <sys/time.h>
+ #include <sys/socket.h>
+ #include <netinet/in.h>
+ #include <arpa/inet.h>
+ #include <netdb.h>
+ #include <time.h>
+ #include <dirent.h>
+ #include <errno.h>
+ #include <iostream>
+ #include <unistd.h>
+
+ #include <cstdio>
+ #include <cstring>
+ #include <pthread.h>
+ #include <semaphore.h>
+ #include <errno.h>
+ #include <fcntl.h>
+
+ typedef int SOCKET;
+ enum
+ {
+ INVALID_SOCKET = -1,
+ };
+ #define closesocket close
+ #define SocketError errno
+#if !defined(ANDROID_NDK)
+ #include <tr1/memory>
+#endif
+#endif
+
+#if !defined(ANDROID_NDK)
+ #define USE_SQUIRREL
+#endif
+
+#if defined(ANDROID_NDK)
+ #define FILE_IO_PREFIX "/sdcard/mcserver/"
+#else
+ #define FILE_IO_PREFIX ""
+#endif
+
+
+
+
+
+// CRT stuff:
+#include <assert.h>
+#include <stdio.h>
+#include <math.h>
+#include <stdarg.h>
+#include <time.h>
+
+
+
+
+
+// STL stuff:
+#include <vector>
+#include <list>
+#include <deque>
+#include <string>
+#include <map>
+#include <algorithm>
+#include <memory>
+
+
+
+
+
+// Common headers (without macros):
+#include "StringUtils.h"
+#include "OSSupport/CriticalSection.h"
+#include "OSSupport/Event.h"
+#include "OSSupport/IsThread.h"
+#include "OSSupport/File.h"
+
+
+
+
+
+// Common definitions:
+
+/// Evaluates to the number of elements in an array (compile-time!)
+#define ARRAYCOUNT(X) (sizeof(X) / sizeof(*(X)))
+
+/// Allows arithmetic expressions like "32 KiB" (but consider using parenthesis around it, "(32 KiB)" )
+#define KiB * 1024
+#define MiB * 1024 * 1024
+
+/// Faster than (int)floorf((float)x / (float)div)
+#define FAST_FLOOR_DIV( x, div ) ( (x) < 0 ? (((int)x / div) - 1) : ((int)x / div) )
+
+// Own version of assert() that writes failed assertions to the log for review
+#ifdef NDEBUG
+ #define ASSERT(x) ((void)0)
+#else
+ #define ASSERT assert
+#endif
+
+// Pretty much the same as ASSERT() but stays in Release builds
+#define VERIFY( x ) ( !!(x) || ( LOGERROR("Verification failed: %s, file %s, line %i", #x, __FILE__, __LINE__ ), exit(1), 0 ) )
+
+
+
+
+
+/// A generic interface used mainly in ForEach() functions
+template <typename Type> class cItemCallback
+{
+public:
+ /// Called for each item in the internal list; return true to stop the loop, or false to continue enumerating
+ virtual bool Item(Type * a_Type) = 0;
+ virtual ~cItemCallback() {}
+} ;
+
+
+
+
diff --git a/Tools/NoiseSpeedTest/NoiseSpeedTest.cpp b/Tools/NoiseSpeedTest/NoiseSpeedTest.cpp
new file mode 100644
index 000000000..6857b1a27
--- /dev/null
+++ b/Tools/NoiseSpeedTest/NoiseSpeedTest.cpp
@@ -0,0 +1,149 @@
+// NoiseSpeedTest.cpp
+
+// Implements the main app entrypoint
+
+/*
+This program compares the performance of the highly-optimized noise implementation in Cuberite, and the Simplex noise.
+Since the Simplex noise is not yet implemented in Cuberite, an own implementation is provided.
+Also, the performance difference between using a float and double as datatype is measured, by using a templatized Simplex noise.
+
+The testing is done on a usage of the generator that is typical for the Cuberite's terrain generator: generate a 3D array of numbers with
+not much variance in the coords. The exact sizes and coord ranges were adapted from the cNoise3DComposable generator.
+*/
+
+#include "Globals.h"
+#include "Noise/Noise.h"
+#include "Noise/InterpolNoise.h"
+#include "SimplexNoise.h"
+
+
+
+
+
+/// The sizes of the interpolated noise that are calculated:
+static const int SIZE_X = 33;
+static const int SIZE_Y = 5;
+static const int SIZE_Z = 5;
+
+
+
+
+
+static void measureClassicNoise(int a_NumIterations)
+{
+ cInterp5DegNoise noise(1);
+ NOISE_DATATYPE total = 0;
+ auto timeStart = std::chrono::high_resolution_clock::now();
+ for (int i = 0; i < a_NumIterations; ++i)
+ {
+ NOISE_DATATYPE out[SIZE_X * SIZE_Y * SIZE_Z];
+ int blockX = i * 16;
+ int blockZ = i * 16;
+ NOISE_DATATYPE startX = 0;
+ NOISE_DATATYPE endX = 257 / 80.0f;
+ NOISE_DATATYPE startY = blockX / 40.0f;
+ NOISE_DATATYPE endY = (blockX + 16) / 40.0f;
+ NOISE_DATATYPE startZ = blockZ / 40.0f;
+ NOISE_DATATYPE endZ = (blockZ + 16) / 40.0f;
+ noise.Generate3D(out, SIZE_X, SIZE_Y, SIZE_Z, startX, endX, startY, endY, startZ, endZ);
+ total += out[0]; // Do not let the optimizer optimize the whole calculation away
+ }
+ auto timeEnd = std::chrono::high_resolution_clock::now();
+ auto msec = std::chrono::duration_cast<std::chrono::milliseconds>(timeEnd - timeStart);
+ printf("Classic noise took %d milliseconds, returned total %f\n", static_cast<int>(msec.count()), total);
+}
+
+
+
+
+
+static void measureSimplexNoiseFloat(int a_NumIterations)
+{
+ typedef float DATATYPE;
+ cSimplexNoise<DATATYPE> noise(1);
+ DATATYPE total = 0;
+ auto timeStart = std::chrono::high_resolution_clock::now();
+ for (int i = 0; i < a_NumIterations; ++i)
+ {
+ DATATYPE out[SIZE_X * SIZE_Y * SIZE_Z];
+ int blockX = i * 16;
+ int blockZ = i * 16;
+ DATATYPE startX = 0;
+ DATATYPE endX = 257 / 80.0f;
+ DATATYPE startY = blockX / 40.0f;
+ DATATYPE endY = (blockX + 16) / 40.0f;
+ DATATYPE startZ = blockZ / 40.0f;
+ DATATYPE endZ = (blockZ + 16) / 40.0f;
+ noise.Generate3D(out, SIZE_X, SIZE_Y, SIZE_Z, startX, endX, startY, endY, startZ, endZ);
+ total += out[0]; // Do not let the optimizer optimize the whole calculation away
+ }
+ auto timeEnd = std::chrono::high_resolution_clock::now();
+ auto msec = std::chrono::duration_cast<std::chrono::milliseconds>(timeEnd - timeStart);
+ printf("SimplexNoise<float> took %d milliseconds, returned total %f\n", static_cast<int>(msec.count()), total);
+}
+
+
+
+
+
+static void measureSimplexNoiseDouble(int a_NumIterations)
+{
+ typedef double DATATYPE;
+ cSimplexNoise<DATATYPE> noise(1);
+ DATATYPE total = 0;
+ auto timeStart = std::chrono::high_resolution_clock::now();
+ for (int i = 0; i < a_NumIterations; ++i)
+ {
+ DATATYPE out[SIZE_X * SIZE_Y * SIZE_Z];
+ int blockX = i * 16;
+ int blockZ = i * 16;
+ DATATYPE startX = 0;
+ DATATYPE endX = 257 / 80.0f;
+ DATATYPE startY = blockX / 40.0f;
+ DATATYPE endY = (blockX + 16) / 40.0f;
+ DATATYPE startZ = blockZ / 40.0f;
+ DATATYPE endZ = (blockZ + 16) / 40.0f;
+ noise.Generate3D(out, SIZE_X, SIZE_Y, SIZE_Z, startX, endX, startY, endY, startZ, endZ);
+ total += out[0]; // Do not let the optimizer optimize the whole calculation away
+ }
+ auto timeEnd = std::chrono::high_resolution_clock::now();
+ auto msec = std::chrono::duration_cast<std::chrono::milliseconds>(timeEnd - timeStart);
+ printf("SimplexNoise<double> took %d milliseconds, returned total %f\n", static_cast<int>(msec.count()), total);
+}
+
+
+
+
+
+int main(int argc, char ** argv)
+{
+ int numIterations = 10000;
+ if (argc > 1)
+ {
+ numIterations = std::atoi(argv[1]);
+ if (numIterations < 10)
+ {
+ printf("Invalid number of iterations, using 1000 instead\n");
+ numIterations = 1000;
+ }
+ }
+
+ // Perform each test twice, to account for cache-warmup:
+ measureClassicNoise(numIterations);
+ measureClassicNoise(numIterations);
+ measureSimplexNoiseFloat(numIterations);
+ measureSimplexNoiseFloat(numIterations);
+ measureSimplexNoiseDouble(numIterations);
+ measureSimplexNoiseDouble(numIterations);
+
+ // If build on Windows using MSVC, wait for a keypress before ending:
+ #ifdef _MSC_VER
+ getchar();
+ #endif
+
+ return 0;
+}
+
+
+
+
diff --git a/Tools/NoiseSpeedTest/NoiseSpeedTest.h b/Tools/NoiseSpeedTest/NoiseSpeedTest.h
new file mode 100644
index 000000000..74a0108e6
--- /dev/null
+++ b/Tools/NoiseSpeedTest/NoiseSpeedTest.h
@@ -0,0 +1,5 @@
+// NoiseSpeedTest.h
+
+
+
+
diff --git a/Tools/NoiseSpeedTest/SimplexNoise.h b/Tools/NoiseSpeedTest/SimplexNoise.h
new file mode 100644
index 000000000..33af8f007
--- /dev/null
+++ b/Tools/NoiseSpeedTest/SimplexNoise.h
@@ -0,0 +1,263 @@
+// SimplexNoise.h
+
+// Declares and implements the simplex noise, using a template parameter for the underlying datatype
+
+/*
+Note:
+This code has been adapted from the public domain code by Stefan Gustavson, available at
+http://staffwww.itn.liu.se/~stegu/simplexnoise/simplexnoise.pdf
+*/
+
+#include <random>
+
+
+
+
+
+template<typename Datatype>
+class cSimplexNoise
+{
+public:
+ cSimplexNoise(int a_Seed)
+ {
+ // Based on the seed, initialize the permutation table, using a simple LCG and swapping
+
+ // Initialize with sorted sequence:
+ for (size_t i = 0; i < ARRAYCOUNT(m_Perm) / 2; i++)
+ {
+ m_Perm[i] = static_cast<int>(i);
+ }
+
+ // Use swaps to randomize:
+ std::linear_congruential_engine<unsigned, 48271, 0, 2147483647> lcg(a_Seed);
+ for (size_t i = 0; i < 2000; i++)
+ {
+ std::swap(m_Perm[lcg() % (ARRAYCOUNT(m_Perm) / 2)], m_Perm[lcg() % (ARRAYCOUNT(m_Perm) / 2)]);
+ }
+
+ // Copy to the upper half of the buffer (to avoid the need for modulo when accessing neighbors):
+ for (size_t i = ARRAYCOUNT(m_Perm) / 2; i < ARRAYCOUNT(m_Perm); i++)
+ {
+ m_Perm[i] = m_Perm[i - ARRAYCOUNT(m_Perm) / 2];
+ }
+
+ // Copy to the "modulo 12" table to optimize away four modulo ops per value calculation:
+ for (size_t i = 0; i < ARRAYCOUNT(m_Perm); i++)
+ {
+ m_PermMod12[i] = m_Perm[i] % 12;
+ }
+ }
+
+
+
+ /** Returns a dot product of an int vector with a Datatype vector. */
+ inline Datatype dot(const int * g, const Datatype x, const Datatype y, const Datatype z)
+ {
+ return g[0] * x + g[1] * y + g[2] * z;
+ }
+
+
+
+ /** Returns a dot product of two Datatype vectors. */
+ inline Datatype dot(const Datatype * g, const Datatype x, const Datatype y, const Datatype z)
+ {
+ return g[0] * x + g[1] * y + g[2] * z;
+ }
+
+
+
+ /** Returns the floor of the specified value, already type-cast to proper int type. */
+ inline int datafloor(const Datatype a_Val)
+ {
+ return (a_Val > 0) ? static_cast<int>(a_Val) : static_cast<int>(a_Val - 1); // This is faster than std::floor()
+ }
+
+
+ /** Returns a single noise value based on the 3D coords. */
+ Datatype GetValueAt3D(const Datatype a_X, const Datatype a_Y, const Datatype a_Z)
+ {
+ // The gradients are the midpoints of the vertices of a cube.
+ static const Datatype grad3[12][3] = {
+ {1, 1, 0}, {-1, 1, 0}, {1, -1, 0}, {-1, -1, 0},
+ {1, 0, 1}, {-1, 0, 1}, {1, 0, -1}, {-1, 0, -1},
+ {0, 1, 1}, { 0, -1, 1}, {0, 1, -1}, { 0, -1, -1}
+ };
+
+ // Skew factors:
+ static const Datatype F3 = static_cast<Datatype>(1.0 / 3.0);
+ static const Datatype G3 = static_cast<Datatype>(1.0 / 6.0);
+
+ // Noise contributions from the four corners:
+ Datatype n0, n1, n2, n3;
+
+ // Skew the input space to determine which simplex cell we're in
+ Datatype s = (a_X + a_Y + a_Z) * F3;
+ int i = datafloor(a_X + s);
+ int j = datafloor(a_Y + s);
+ int k = datafloor(a_Z + s);
+
+ // Unskew back into the XYZ space to calculate the distances from cell origin:
+ Datatype t = (i + j + k) * G3;
+ Datatype X0 = i - t;
+ Datatype Y0 = j - t;
+ Datatype Z0 = k - t;
+ Datatype x0 = a_X - X0;
+ Datatype y0 = a_Y - Y0;
+ Datatype z0 = a_Z - Z0;
+
+ // For the 3D case, the simplex shape is a slightly irregular tetrahedron.
+ // Determine which simplex we are in.
+ int i1, j1, k1; // Offsets for second corner of simplex in IJK coords
+ int i2, j2, k2; // Offsets for third corner of simplex in IJK coords
+ if (x0 >= y0)
+ {
+ if (y0 >= z0)
+ {
+ // X Y Z order
+ i1 = 1; j1 = 0; k1 = 0; i2 = 1; j2 = 1; k2 = 0;
+ }
+ else if (x0 >= z0)
+ {
+ // X Z Y order
+ i1 = 1; j1 = 0; k1 = 0; i2 = 1; j2 = 0; k2 = 1;
+ }
+ else
+ {
+ // Z X Y order
+ i1 = 0; j1 = 0; k1 = 1; i2 = 1; j2 = 0; k2 = 1;
+ }
+ }
+ else
+ {
+ if (y0 < z0)
+ {
+ // Z Y X order
+ i1 = 0; j1 = 0; k1 = 1; i2 = 0; j2 = 1; k2 = 1;
+ }
+ else if (x0 < z0)
+ {
+ // Y Z X order
+ i1 = 0; j1 = 1; k1 = 0; i2 = 0; j2 = 1; k2 = 1;
+ }
+ else
+ {
+ // Y X Z order
+ i1 = 0; j1 = 1; k1 = 0; i2 = 1; j2 = 1; k2 = 0;
+ }
+ }
+
+ // A step of (1, 0, 0) in IJK means a step of (1 - c, -c, -c) in XYZ,
+ // a step of (0, 1, 0) in IJK means a step of (-c, 1 - c, -c) in XYZ, and
+ // a step of (0, 0, 1) in IJK means a step of (-c, -c, 1 - c) in XYZ, where c = G3 = 1 / 6.
+ Datatype x1 = x0 - i1 + G3; // Offsets for second corner in XYZ coords
+ Datatype y1 = y0 - j1 + G3;
+ Datatype z1 = z0 - k1 + G3;
+ Datatype x2 = x0 - i2 + static_cast<Datatype>(2) * G3; // Offsets for third corner in XYZ coords
+ Datatype y2 = y0 - j2 + static_cast<Datatype>(2) * G3;
+ Datatype z2 = z0 - k2 + static_cast<Datatype>(2) * G3;
+ Datatype x3 = x0 - static_cast<Datatype>(1) + static_cast<Datatype>(3) * G3; // Offsets for last corner in XYZ coords
+ Datatype y3 = y0 - static_cast<Datatype>(1) + static_cast<Datatype>(3) * G3;
+ Datatype z3 = z0 - static_cast<Datatype>(1) + static_cast<Datatype>(3) * G3;
+
+ // Work out the hashed gradient indices of the four simplex corners
+ int ii = i & 255;
+ int jj = j & 255;
+ int kk = k & 255;
+ int gi0 = m_PermMod12[ii + m_Perm[jj + m_Perm[kk]]];
+ int gi1 = m_PermMod12[ii + i1 + m_Perm[jj + j1 + m_Perm[kk + k1]]];
+ int gi2 = m_PermMod12[ii + i2 + m_Perm[jj + j2 + m_Perm[kk + k2]]];
+ int gi3 = m_PermMod12[ii + 1 + m_Perm[jj + 1 + m_Perm[kk + 1]]];
+
+ // Calculate the contribution from the four corners
+ Datatype t0 = static_cast<Datatype>(0.6) - x0 * x0 - y0 * y0 - z0 * z0;
+ if (t0 < 0)
+ {
+ n0 = 0.0;
+ }
+ else
+ {
+ t0 *= t0;
+ n0 = t0 * t0 * dot(grad3[gi0], x0, y0, z0);
+ }
+
+ Datatype t1 = static_cast<Datatype>(0.6) - x1 * x1 - y1 * y1 - z1 * z1;
+ if (t1 < 0)
+ {
+ n1 = 0.0;
+ }
+ else
+ {
+ t1 *= t1;
+ n1 = t1 * t1 * dot(grad3[gi1], x1, y1, z1);
+ }
+
+ Datatype t2 = static_cast<Datatype>(0.6) - x2 * x2 - y2 * y2 - z2 * z2;
+ if (t2 < 0)
+ {
+ n2 = 0.0;
+ }
+ else
+ {
+ t2 *= t2;
+ n2 = t2 * t2 * dot(grad3[gi2], x2, y2, z2);
+ }
+
+ Datatype t3 = static_cast<Datatype>(0.6) - x3 * x3 - y3 * y3 - z3 * z3;
+ if (t3 < 0)
+ {
+ n3 = 0.0;
+ }
+ else
+ {
+ t3 *= t3;
+ n3 = t3 * t3 * dot(grad3[gi3], x3, y3, z3);
+ }
+
+ // Add contributions from each corner to get the final noise value.
+ // The result is scaled to stay just inside [-1, 1]
+ return static_cast<Datatype>(32) * (n0 + n1 + n2 + n3);
+ }
+
+
+
+
+ /** Generates the 3D version of the SImplex noise.
+ a_Out is the 3D array into which the noise is output. Organized as [x + a_SizeX * y + a_SizeX * a_SizeY * z].
+ a_SizeX, a_SizeY, a_SizeZ are the dimensions of the a_Out array.
+ a_Start and a_End are the coords of the 3D array in the noise-space. */
+ void Generate3D(
+ Datatype * a_Out,
+ int a_SizeX, int a_SizeY, int a_SizeZ,
+ Datatype a_StartX, Datatype a_EndX,
+ Datatype a_StartY, Datatype a_EndY,
+ Datatype a_StartZ, Datatype a_EndZ
+ )
+ {
+ Datatype * out = a_Out;
+ for (int z = 0; z < a_SizeZ; ++z)
+ {
+ Datatype nz = a_StartZ + z * (a_EndZ - a_StartZ) / a_SizeZ;
+ for (int y = 0; y < a_SizeY; ++y)
+ {
+ Datatype ny = a_StartY + y * (a_EndY - a_StartY) / a_SizeY;
+ for (int x = 0; x < a_SizeX; ++x)
+ {
+ Datatype nx = a_StartX + x * (a_EndX - a_StartX) / a_SizeX;
+ *out = GetValueAt3D(nx, ny, nz);
+ ++out;
+ } // for x
+ } // for y
+ } // for z
+ }
+
+protected:
+ /** The permutation table, initialized by the seed. */
+ int m_Perm[512];
+
+ /** A copy of the permutation table, with each item modulo 12, to avoid 4 modulo operations per value calculation. */
+ int m_PermMod12[512];
+};
+
+
+
+