Add new example with implementation of Perlin Noise

~4.2x speedup versus serial on OSX / gcc.
~2.9x speedup versus serial on Windows / MSVC.

builtins.m4

@@ -1431,26 +1431,24 @@ pl_done:
 define(`gen_gather', `
 ;; Define the utility function to do the gather operation for a single element
 ;; of the type
-define internal <$1 x $2> @__gather_elt_$2(i64 %ptr64, <$1 x i32> %offsets, <$1 x $2> %ret,
+define internal <$1 x $2> @__gather_elt_$2(i8 * %ptr, <$1 x i32> %offsets, <$1 x $2> %ret,
                                            i32 %lane) nounwind readonly alwaysinline {
   ; compute address for this one from the base
   %offset32 = extractelement <$1 x i32> %offsets, i32 %lane
-  %offset64 = zext i32 %offset32 to i64
+  %ptroffset = getelementptr i8 * %ptr, i32 %offset32
-  %ptrdelta = add i64 %ptr64, %offset64
+  %ptrcast = bitcast i8 * %ptroffset to $2 *
-  %ptr = inttoptr i64 %ptrdelta to $2 *
 
   ; load value and insert into returned value
-  %val = load $2 *%ptr
+  %val = load $2 *%ptrcast
   %updatedret = insertelement <$1 x $2> %ret, $2 %val, i32 %lane
   ret <$1 x $2> %updatedret
 }
 
 
-define <$1 x $2> @__gather_base_offsets_$2(i8*, <$1 x i32> %offsets,
+define <$1 x $2> @__gather_base_offsets_$2(i8 * %ptr, <$1 x i32> %offsets,
                                            <$1 x i32> %vecmask) nounwind readonly alwaysinline {
 entry:
   %mask = call i32 @__movmsk(<$1 x i32> %vecmask)
-  %ptr64 = ptrtoint i8 * %0 to i64
 
   %maskKnown = call i1 @__is_compile_time_constant_mask(<$1 x i32> %vecmask)
   br i1 %maskKnown, label %known_mask, label %unknown_mask
@@ -1474,10 +1472,10 @@ unknown_mask:
                                      <$1 x i32> %vecmask)
   %newOffsets = load <$1 x i32> * %offsetsPtr
 
-  %ret0 = call <$1 x $2> @__gather_elt_$2(i64 %ptr64, <$1 x i32> %newOffsets,
+  %ret0 = call <$1 x $2> @__gather_elt_$2(i8 * %ptr, <$1 x i32> %newOffsets,
                                           <$1 x $2> undef, i32 0)
   forloop(lane, 1, eval($1-1), 
-          `patsubst(patsubst(`%retLANE = call <$1 x $2> @__gather_elt_$2(i64 %ptr64, 
+          `patsubst(patsubst(`%retLANE = call <$1 x $2> @__gather_elt_$2(i8 * %ptr, 
                                 <$1 x i32> %newOffsets, <$1 x $2> %retPREV, i32 LANE)
                     ', `LANE', lane), `PREV', eval(lane-1))')
   ret <$1 x $2> %ret`'eval($1-1)

examples/README.txt

@@ -57,6 +57,13 @@ Linux, a pthreads-based task system is used (tasks_pthreads.cpp).  When
 using tasks with ispc, no task system is mandated; the user is free to plug
 in any task system they want, for ease of interoperating with existing task
 systems.
+
+Noise
+=====
+
+This example has an implementation of Ken Perlin's procedural "noise"
+function, as described in his 2002 "Improving Noise" SIGGRAPH paper.
+
  
 Options
 =======

examples/cpuid.h

@@ -48,19 +48,19 @@ static void __cpuid(int info[4], int infoType) {
 inline bool CPUSupportsSSE2() {
     int info[4];
     __cpuid(info, 1);
-    return (info[3] & (1 << 26));
+    return (info[3] & (1 << 26)) != 0;
 }
 
 inline bool CPUSupportsSSE4() {
     int info[4];
     __cpuid(info, 1);
-    return (info[2] & (1 << 19));
+    return (info[2] & (1 << 19)) != 0;
 }
 
 inline bool CPUSupportsAVX() {
     int info[4];
     __cpuid(info, 1);
-    return (info[2] & (1 << 28));
+    return (info[2] & (1 << 28)) != 0;
 }
 
 #endif // ISPC_CPUID_H

examples/examples.sln

@@ -15,6 +15,8 @@ Project("{8BC9CEB8-8B4A-11D0-8D11-00A0C91BC942}") = "mandelbrot_tasks", "mandelb
 EndProject
 Project("{8BC9CEB8-8B4A-11D0-8D11-00A0C91BC942}") = "aobench_instrumented", "aobench_instrumented\aobench_instrumented.vcxproj", "{B3B4AE3D-6D5A-4CF9-AF5B-43CF2131B958}"
 EndProject
+Project("{8BC9CEB8-8B4A-11D0-8D11-00A0C91BC942}") = "noise", "noise\noise.vcxproj", "{0E0886D8-8B5E-4EAF-9A21-91E63DAF81FD}"
+EndProject
 Global
 	GlobalSection(SolutionConfigurationPlatforms) = preSolution
 		Debug|Win32 = Debug|Win32
@@ -79,6 +81,14 @@ Global
 		{B3B4AE3D-6D5A-4CF9-AF5B-43CF2131B958}.Release|Win32.Build.0 = Release|Win32
 		{B3B4AE3D-6D5A-4CF9-AF5B-43CF2131B958}.Release|x64.ActiveCfg = Release|x64
 		{B3B4AE3D-6D5A-4CF9-AF5B-43CF2131B958}.Release|x64.Build.0 = Release|x64
+		{0E0886D8-8B5E-4EAF-9A21-91E63DAF81FD}.Debug|Win32.ActiveCfg = Debug|Win32
+		{0E0886D8-8B5E-4EAF-9A21-91E63DAF81FD}.Debug|Win32.Build.0 = Debug|Win32
+		{0E0886D8-8B5E-4EAF-9A21-91E63DAF81FD}.Debug|x64.ActiveCfg = Debug|x64
+		{0E0886D8-8B5E-4EAF-9A21-91E63DAF81FD}.Debug|x64.Build.0 = Debug|x64
+		{0E0886D8-8B5E-4EAF-9A21-91E63DAF81FD}.Release|Win32.ActiveCfg = Release|Win32
+		{0E0886D8-8B5E-4EAF-9A21-91E63DAF81FD}.Release|Win32.Build.0 = Release|Win32
+		{0E0886D8-8B5E-4EAF-9A21-91E63DAF81FD}.Release|x64.ActiveCfg = Release|x64
+		{0E0886D8-8B5E-4EAF-9A21-91E63DAF81FD}.Release|x64.Build.0 = Release|x64
 	EndGlobalSection
 	GlobalSection(SolutionProperties) = preSolution
 		HideSolutionNode = FALSE

examples/noise/.gitignore

@@ -0,0 +1,3 @@
+noise
+*.ppm
+objs

examples/noise/Makefile

@@ -0,0 +1,26 @@
+
+CXX=g++ -m64
+CXXFLAGS=-Iobjs/ -O3 -Wall
+ISPC=ispc
+ISPCFLAGS=-O2 --target=sse4 --arch=x86-64
+
+default: noise
+
+.PHONY: dirs clean
+
+dirs:
+	/bin/mkdir -p objs/
+
+clean:
+	/bin/rm -rf objs *~ noise
+
+noise: dirs objs/noise.o objs/noise_serial.o objs/noise_ispc.o
+	$(CXX) $(CXXFLAGS) -o $@ objs/noise.o objs/noise_ispc.o objs/noise_serial.o -lm
+
+objs/%.o: %.cpp
+	$(CXX) $< $(CXXFLAGS) -c -o $@
+
+objs/noise.o: objs/noise_ispc.h 
+
+objs/%_ispc.h objs/%_ispc.o: %.ispc
+	$(ISPC) $(ISPCFLAGS) $< -o objs/$*_ispc.o -h objs/$*_ispc.h

examples/noise/noise.cpp

@@ -0,0 +1,150 @@
+/*
+  Copyright (c) 2010-2011, Intel Corporation
+  All rights reserved.
+
+  Redistribution and use in source and binary forms, with or without
+  modification, are permitted provided that the following conditions are
+  met:
+
+    * Redistributions of source code must retain the above copyright
+      notice, this list of conditions and the following disclaimer.
+
+    * Redistributions in binary form must reproduce the above copyright
+      notice, this list of conditions and the following disclaimer in the
+      documentation and/or other materials provided with the distribution.
+
+    * Neither the name of Intel Corporation nor the names of its
+      contributors may be used to endorse or promote products derived from
+      this software without specific prior written permission.
+
+
+   THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS
+   IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
+   TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A
+   PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER
+   OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
+   EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
+   PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
+   PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
+   LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
+   NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
+   SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.  
+*/
+
+#ifdef _MSC_VER
+#define _CRT_SECURE_NO_WARNINGS
+#define NOMINMAX
+#pragma warning (disable: 4244)
+#pragma warning (disable: 4305)
+#endif
+
+#include <stdio.h>
+#include <algorithm>
+#include "../timing.h"
+#include "../cpuid.h"
+#include "noise_ispc.h"
+using namespace ispc;
+
+extern void noise_serial(float x0, float y0, float x1, float y1,
+                         int width, int height, float output[]);
+
+/* Write a PPM image file with the image */
+static void
+writePPM(float *buf, int width, int height, const char *fn) {
+    FILE *fp = fopen(fn, "wb");
+    fprintf(fp, "P6\n");
+    fprintf(fp, "%d %d\n", width, height);
+    fprintf(fp, "255\n");
+    for (int i = 0; i < width*height; ++i) {
+        float v = buf[i] * 255.f;
+        if (v < 0) v = 0;
+        if (v > 255) v = 255;
+        for (int j = 0; j < 3; ++j)
+            fputc((char)v, fp);
+    }
+    fclose(fp);
+}
+
+
+// Make sure that the vector ISA used during compilation is supported by
+// the processor.  The ISPC_TARGET_* macro is set in the ispc-generated
+// header file that we include above.
+static void
+ensureTargetISAIsSupported() {
+#if defined(ISPC_TARGET_SSE2)
+    bool isaSupported = CPUSupportsSSE2();
+    const char *target = "SSE2";
+#elif defined(ISPC_TARGET_SSE4)
+    bool isaSupported = CPUSupportsSSE4();
+    const char *target = "SSE4";
+#elif defined(ISPC_TARGET_AVX)
+    bool isaSupported = CPUSupportsAVX();
+    const char *target = "AVX";
+#else
+#error "Unknown ISPC_TARGET_* value"
+#endif
+    if (!isaSupported) {
+        fprintf(stderr, "***\n*** Error: the ispc-compiled code uses the %s instruction "
+                "set, which isn't\n***        supported by this computer's CPU!\n", target);
+        fprintf(stderr, "***\n***        Please modify the "
+#ifdef _MSC_VER
+                "MSVC project file "
+#else
+                "Makefile "
+#endif
+                "to select another target (e.g. sse2)\n***\n");
+        exit(1);
+    }
+}
+
+
+int main() {
+    unsigned int width = 768;
+    unsigned int height = 768;
+    float x0 = -10;
+    float x1 = 10;
+    float y0 = -10;
+    float y1 = 10;
+
+    float *buf = new float[width*height];
+
+    ensureTargetISAIsSupported();
+
+    //
+    // Compute the image using the ispc implementation; report the minimum
+    // time of three runs.
+    //
+    double minISPC = 1e30;
+    for (int i = 0; i < 3; ++i) {
+        reset_and_start_timer();
+        noise_ispc(x0, y0, x1, y1, width, height, buf);
+        double dt = get_elapsed_mcycles();
+        minISPC = std::min(minISPC, dt);
+    }
+
+    printf("[noise ispc]:\t\t\t[%.3f] million cycles\n", minISPC);
+    writePPM(buf, width, height, "noise-ispc.ppm");
+
+    // Clear out the buffer
+    for (unsigned int i = 0; i < width * height; ++i)
+        buf[i] = 0;
+
+    // 
+    // And run the serial implementation 3 times, again reporting the
+    // minimum time.
+    //
+    double minSerial = 1e30;
+    for (int i = 0; i < 3; ++i) {
+        reset_and_start_timer();
+        noise_serial(x0, y0, x1, y1, width, height, buf);
+        double dt = get_elapsed_mcycles();
+        minSerial = std::min(minSerial, dt);
+    }
+
+    printf("[noise serial]:\t\t\t[%.3f] millon cycles\n", minSerial);
+    writePPM(buf, width, height, "noise-serial.ppm");
+
+    printf("\t\t\t\t(%.2fx speedup from ISPC)\n", minSerial/minISPC);
+
+    return 0;
+}

examples/noise/noise.ispc

@@ -0,0 +1,164 @@
+/*
+  Copyright (c) 2010-2011, Intel Corporation
+  All rights reserved.
+
+  Redistribution and use in source and binary forms, with or without
+  modification, are permitted provided that the following conditions are
+  met:
+
+    * Redistributions of source code must retain the above copyright
+      notice, this list of conditions and the following disclaimer.
+
+    * Redistributions in binary form must reproduce the above copyright
+      notice, this list of conditions and the following disclaimer in the
+      documentation and/or other materials provided with the distribution.
+
+    * Neither the name of Intel Corporation nor the names of its
+      contributors may be used to endorse or promote products derived from
+      this software without specific prior written permission.
+
+
+   THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS
+   IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
+   TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A
+   PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER
+   OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
+   EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
+   PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
+   PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
+   LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
+   NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
+   SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.  
+*/
+
+#define NOISE_PERM_SIZE 256
+
+static uniform int NoisePerm[2 * NOISE_PERM_SIZE] = {
+    151, 160, 137, 91, 90, 15, 131, 13, 201, 95, 96, 53, 194, 233, 7, 225, 140,
+    36, 103, 30, 69, 142, 8, 99, 37, 240, 21, 10, 23, 190, 6, 148, 247, 120,
+    234, 75, 0, 26, 197, 62, 94, 252, 219, 203, 117, 35, 11, 32, 57, 177, 33,
+    88, 237, 149, 56, 87, 174, 20, 125, 136, 171, 168,  68, 175, 74, 165, 71, 
+    134, 139, 48, 27, 166, 77, 146, 158, 231, 83, 111, 229, 122, 60, 211, 133, 
+    230, 220, 105, 92, 41, 55, 46, 245, 40, 244, 102, 143, 54, 65, 25, 63, 161,
+    1, 216, 80, 73, 209, 76, 132, 187, 208,  89, 18, 169, 200, 196, 135, 130, 
+    116, 188, 159, 86, 164, 100, 109, 198, 173, 186,  3, 64, 52, 217, 226, 250,
+    124, 123, 5, 202, 38, 147, 118, 126, 255, 82, 85, 212, 207, 206, 59, 227, 
+    47, 16, 58, 17, 182, 189, 28, 42, 223, 183, 170, 213, 119, 248, 152,  2, 44,
+    154, 163, 70, 221, 153, 101, 155, 167,  43, 172, 9, 129, 22, 39, 253,  19, 
+    98, 108, 110, 79, 113, 224, 232, 178, 185,  112, 104, 218, 246, 97, 228, 251,
+    34, 242, 193, 238, 210, 144, 12, 191, 179, 162, 241, 81, 51, 145, 235, 249,
+    14, 239, 107, 49, 192, 214,  31, 181, 199, 106, 157, 184, 84, 204, 176, 115,
+    121, 50, 45, 127,  4, 150, 254, 138, 236, 205, 93, 222, 114, 67, 29, 24, 72, 
+    243, 141, 128, 195, 78, 66, 215, 61, 156, 180, 151, 160, 137, 91, 90, 15,
+    131, 13, 201, 95, 96, 53, 194, 233, 7, 225, 140, 36, 103, 30, 69, 142, 8, 99,
+    37, 240, 21, 10, 23, 190, 6, 148, 247, 120, 234, 75, 0, 26, 197, 62, 94, 252,
+    219, 203, 117, 35, 11, 32, 57, 177, 33, 88, 237, 149, 56, 87, 174, 20, 125, 
+    136, 171, 168,  68, 175, 74, 165, 71, 134, 139, 48, 27, 166, 77, 146, 158,
+    231, 83, 111, 229, 122, 60, 211, 133, 230, 220, 105, 92, 41, 55, 46, 245,
+    40, 244, 102, 143, 54,  65, 25, 63, 161,  1, 216, 80, 73, 209, 76, 132, 187,
+    208,  89, 18, 169, 200, 196, 135, 130, 116, 188, 159, 86, 164, 100, 109, 
+    198, 173, 186,  3, 64, 52, 217, 226, 250, 124, 123, 5, 202, 38, 147, 118,
+    126, 255, 82, 85, 212, 207, 206, 59, 227, 47, 16, 58, 17, 182, 189, 28, 42,
+    223, 183, 170, 213, 119, 248, 152,  2, 44, 154, 163, 70, 221, 153, 101, 155, 
+    167,  43, 172, 9, 129, 22, 39, 253,  19, 98, 108, 110, 79, 113, 224, 232,
+    178, 185,  112, 104, 218, 246, 97, 228, 251, 34, 242, 193, 238, 210, 144,
+    12, 191, 179, 162, 241,  81, 51, 145, 235, 249, 14, 239, 107, 49, 192, 214,
+    31, 181, 199, 106, 157, 184,  84, 204, 176, 115, 121, 50, 45, 127,  4, 150,
+    254, 138, 236, 205, 93, 222, 114, 67, 29, 24, 72, 243, 141, 128, 195, 78, 
+    66, 215, 61, 156, 180
+};
+
+
+inline float SmoothStep(float low, float high, float value) {
+    float v = clamp((value - low) / (high - low), 0.f, 1.f);
+    return v * v * (-2.f * v  + 3.f);
+}
+
+
+inline int Floor2Int(float val) {
+    return (int)floor(val);
+}
+
+
+inline float Grad(int x, int y, int z, float dx, float dy, float dz) {
+    int h = NoisePerm[NoisePerm[NoisePerm[x]+y]+z];
+    h &= 15;
+    float u = h<8 || h==12 || h==13 ? dx : dy;
+    float v = h<4 || h==12 || h==13 ? dy : dz;
+    return ((h&1) ? -u : u) + ((h&2) ? -v : v);
+}
+
+
+inline float NoiseWeight(float t) {
+    float t3 = t*t*t;
+    float t4 = t3*t;
+    return 6.f*t4*t - 15.f*t4 + 10.f*t3;
+}
+
+
+inline float Lerp(float t, float low, float high) {
+    return (1. - t) * low + t * high;
+}
+
+
+static float Noise(float x, float y, float z) {
+    // Compute noise cell coordinates and offsets
+    int ix = Floor2Int(x), iy = Floor2Int(y), iz = Floor2Int(z);
+    float dx = x - ix, dy = y - iy, dz = z - iz;
+
+    // Compute gradient weights
+    ix &= (NOISE_PERM_SIZE-1);
+    iy &= (NOISE_PERM_SIZE-1);
+    iz &= (NOISE_PERM_SIZE-1);
+    float w000 = Grad(ix,   iy,   iz,   dx,   dy,   dz);
+    float w100 = Grad(ix+1, iy,   iz,   dx-1, dy,   dz);
+    float w010 = Grad(ix,   iy+1, iz,   dx,   dy-1, dz);
+    float w110 = Grad(ix+1, iy+1, iz,   dx-1, dy-1, dz);
+    float w001 = Grad(ix,   iy,   iz+1, dx,   dy,   dz-1);
+    float w101 = Grad(ix+1, iy,   iz+1, dx-1, dy,   dz-1);
+    float w011 = Grad(ix,   iy+1, iz+1, dx,   dy-1, dz-1);
+    float w111 = Grad(ix+1, iy+1, iz+1, dx-1, dy-1, dz-1);
+
+    // Compute trilinear interpolation of weights
+    float wx = NoiseWeight(dx), wy = NoiseWeight(dy), wz = NoiseWeight(dz);
+    float x00 = Lerp(wx, w000, w100);
+    float x10 = Lerp(wx, w010, w110);
+    float x01 = Lerp(wx, w001, w101);
+    float x11 = Lerp(wx, w011, w111);
+    float y0 = Lerp(wy, x00, x10);
+    float y1 = Lerp(wy, x01, x11);
+    return Lerp(wz, y0, y1);
+}
+
+
+static float Turbulence(float x, float y, float z, int octaves) {
+    float omega = 0.6;
+
+    float sum = 0., lambda = 1., o = 1.;
+    for (int i = 0; i < octaves; ++i) {
+        sum += abs(o * Noise(lambda * x, lambda * y, lambda * z));
+        lambda *= 1.99f;
+        o *= omega;
+    }
+    return sum * 0.5;
+}
+
+
+export void noise_ispc(uniform float x0, uniform float y0, uniform float x1, 
+                       uniform float y1, uniform int width, uniform int height, 
+                       uniform float output[])
+{
+    uniform float dx = (x1 - x0) / width;
+    uniform float dy = (y1 - y0) / height;
+
+    for (uniform int j = 0; j < height; j++) {
+        for (uniform int i = 0; i < width; i += programCount) {
+            float x = x0 + (i + programIndex) * dx;
+            float y = y0 + j * dy;
+
+            int index = (j * width + i + programIndex);
+            output[index] = Turbulence(x, y, 0.6, 8);
+        }
+    }
+}
+

examples/noise/noise.vcxproj

@@ -0,0 +1,167 @@
+<?xml version="1.0" encoding="utf-8"?>
+<Project DefaultTargets="Build" ToolsVersion="4.0" xmlns="http://schemas.microsoft.com/developer/msbuild/2003">
+  <ItemGroup Label="ProjectConfigurations">
+    <ProjectConfiguration Include="Debug|Win32">
+      <Configuration>Debug</Configuration>
+      <Platform>Win32</Platform>
+    </ProjectConfiguration>
+    <ProjectConfiguration Include="Debug|x64">
+      <Configuration>Debug</Configuration>
+      <Platform>x64</Platform>
+    </ProjectConfiguration>
+    <ProjectConfiguration Include="Release|Win32">
+      <Configuration>Release</Configuration>
+      <Platform>Win32</Platform>
+    </ProjectConfiguration>
+    <ProjectConfiguration Include="Release|x64">
+      <Configuration>Release</Configuration>
+      <Platform>x64</Platform>
+    </ProjectConfiguration>
+  </ItemGroup>
+  <PropertyGroup Label="Globals">
+    <ProjectGuid>{0E0886D8-8B5E-4EAF-9A21-91E63DAF81FD}</ProjectGuid>
+    <Keyword>Win32Proj</Keyword>
+    <RootNamespace>noise</RootNamespace>
+  </PropertyGroup>
+  <Import Project="$(VCTargetsPath)\Microsoft.Cpp.Default.props" />
+  <PropertyGroup Condition="'$(Configuration)|$(Platform)'=='Debug|Win32'" Label="Configuration">
+    <ConfigurationType>Application</ConfigurationType>
+    <UseDebugLibraries>true</UseDebugLibraries>
+    <CharacterSet>Unicode</CharacterSet>
+  </PropertyGroup>
+  <PropertyGroup Condition="'$(Configuration)|$(Platform)'=='Debug|x64'" Label="Configuration">
+    <ConfigurationType>Application</ConfigurationType>
+    <UseDebugLibraries>true</UseDebugLibraries>
+    <CharacterSet>Unicode</CharacterSet>
+  </PropertyGroup>
+  <PropertyGroup Condition="'$(Configuration)|$(Platform)'=='Release|Win32'" Label="Configuration">
+    <ConfigurationType>Application</ConfigurationType>
+    <UseDebugLibraries>false</UseDebugLibraries>
+    <WholeProgramOptimization>true</WholeProgramOptimization>
+    <CharacterSet>Unicode</CharacterSet>
+  </PropertyGroup>
+  <PropertyGroup Condition="'$(Configuration)|$(Platform)'=='Release|x64'" Label="Configuration">
+    <ConfigurationType>Application</ConfigurationType>
+    <UseDebugLibraries>false</UseDebugLibraries>
+    <WholeProgramOptimization>true</WholeProgramOptimization>
+    <CharacterSet>Unicode</CharacterSet>
+  </PropertyGroup>
+  <Import Project="$(VCTargetsPath)\Microsoft.Cpp.props" />
+  <ImportGroup Label="ExtensionSettings">
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examples/noise/noise_serial.cpp

@@ -0,0 +1,170 @@
+/*
+  Copyright (c) 2010-2011, Intel Corporation
+  All rights reserved.
+
+  Redistribution and use in source and binary forms, with or without
+  modification, are permitted provided that the following conditions are
+  met:
+
+    * Redistributions of source code must retain the above copyright
+      notice, this list of conditions and the following disclaimer.
+
+    * Redistributions in binary form must reproduce the above copyright
+      notice, this list of conditions and the following disclaimer in the
+      documentation and/or other materials provided with the distribution.
+
+    * Neither the name of Intel Corporation nor the names of its
+      contributors may be used to endorse or promote products derived from
+      this software without specific prior written permission.
+
+
+   THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS
+   IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
+   TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A
+   PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER
+   OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
+   EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
+   PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
+   PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
+   LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
+   NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
+   SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.  
+*/
+
+#include <math.h>
+
+#define NOISE_PERM_SIZE 256
+
+static int NoisePerm[2 * NOISE_PERM_SIZE] = {
+    151, 160, 137, 91, 90, 15, 131, 13, 201, 95, 96, 53, 194, 233, 7, 225, 140,
+    36, 103, 30, 69, 142, 8, 99, 37, 240, 21, 10, 23, 190, 6, 148, 247, 120,
+    234, 75, 0, 26, 197, 62, 94, 252, 219, 203, 117, 35, 11, 32, 57, 177, 33,
+    88, 237, 149, 56, 87, 174, 20, 125, 136, 171, 168,  68, 175, 74, 165, 71, 
+    134, 139, 48, 27, 166, 77, 146, 158, 231, 83, 111, 229, 122, 60, 211, 133, 
+    230, 220, 105, 92, 41, 55, 46, 245, 40, 244, 102, 143, 54, 65, 25, 63, 161,
+    1, 216, 80, 73, 209, 76, 132, 187, 208,  89, 18, 169, 200, 196, 135, 130, 
+    116, 188, 159, 86, 164, 100, 109, 198, 173, 186,  3, 64, 52, 217, 226, 250,
+    124, 123, 5, 202, 38, 147, 118, 126, 255, 82, 85, 212, 207, 206, 59, 227, 
+    47, 16, 58, 17, 182, 189, 28, 42, 223, 183, 170, 213, 119, 248, 152,  2, 44,
+    154, 163, 70, 221, 153, 101, 155, 167,  43, 172, 9, 129, 22, 39, 253,  19, 
+    98, 108, 110, 79, 113, 224, 232, 178, 185,  112, 104, 218, 246, 97, 228, 251,
+    34, 242, 193, 238, 210, 144, 12, 191, 179, 162, 241, 81, 51, 145, 235, 249,
+    14, 239, 107, 49, 192, 214,  31, 181, 199, 106, 157, 184, 84, 204, 176, 115,
+    121, 50, 45, 127,  4, 150, 254, 138, 236, 205, 93, 222, 114, 67, 29, 24, 72, 
+    243, 141, 128, 195, 78, 66, 215, 61, 156, 180, 151, 160, 137, 91, 90, 15,
+    131, 13, 201, 95, 96, 53, 194, 233, 7, 225, 140, 36, 103, 30, 69, 142, 8, 99,
+    37, 240, 21, 10, 23, 190, 6, 148, 247, 120, 234, 75, 0, 26, 197, 62, 94, 252,
+    219, 203, 117, 35, 11, 32, 57, 177, 33, 88, 237, 149, 56, 87, 174, 20, 125, 
+    136, 171, 168,  68, 175, 74, 165, 71, 134, 139, 48, 27, 166, 77, 146, 158,
+    231, 83, 111, 229, 122, 60, 211, 133, 230, 220, 105, 92, 41, 55, 46, 245,
+    40, 244, 102, 143, 54,  65, 25, 63, 161,  1, 216, 80, 73, 209, 76, 132, 187,
+    208,  89, 18, 169, 200, 196, 135, 130, 116, 188, 159, 86, 164, 100, 109, 
+    198, 173, 186,  3, 64, 52, 217, 226, 250, 124, 123, 5, 202, 38, 147, 118,
+    126, 255, 82, 85, 212, 207, 206, 59, 227, 47, 16, 58, 17, 182, 189, 28, 42,
+    223, 183, 170, 213, 119, 248, 152,  2, 44, 154, 163, 70, 221, 153, 101, 155, 
+    167,  43, 172, 9, 129, 22, 39, 253,  19, 98, 108, 110, 79, 113, 224, 232,
+    178, 185,  112, 104, 218, 246, 97, 228, 251, 34, 242, 193, 238, 210, 144,
+    12, 191, 179, 162, 241,  81, 51, 145, 235, 249, 14, 239, 107, 49, 192, 214,
+    31, 181, 199, 106, 157, 184,  84, 204, 176, 115, 121, 50, 45, 127,  4, 150,
+    254, 138, 236, 205, 93, 222, 114, 67, 29, 24, 72, 243, 141, 128, 195, 78, 
+    66, 215, 61, 156, 180
+};
+
+
+inline float Clamp(float v, float low, float high) {
+    return v < low ? low : ((v > high) ? high : v);
+}
+
+
+inline float SmoothStep(float low, float high, float value) {
+    float v = Clamp((value - low) / (high - low), 0.f, 1.f);
+    return v * v * (-2.f * v  + 3.f);
+}
+
+
+inline int Floor2Int(float val) {
+    return (int)floorf(val);
+}
+
+
+inline float Grad(int x, int y, int z, float dx, float dy, float dz) {
+    int h = NoisePerm[NoisePerm[NoisePerm[x]+y]+z];
+    h &= 15;
+    float u = h<8 || h==12 || h==13 ? dx : dy;
+    float v = h<4 || h==12 || h==13 ? dy : dz;
+    return ((h&1) ? -u : u) + ((h&2) ? -v : v);
+}
+
+
+inline float NoiseWeight(float t) {
+    float t3 = t*t*t;
+    float t4 = t3*t;
+    return 6.f*t4*t - 15.f*t4 + 10.f*t3;
+}
+
+
+inline float Lerp(float t, float low, float high) {
+    return (1. - t) * low + t * high;
+}
+
+
+static float Noise(float x, float y, float z) {
+    // Compute noise cell coordinates and offsets
+    int ix = Floor2Int(x), iy = Floor2Int(y), iz = Floor2Int(z);
+    float dx = x - ix, dy = y - iy, dz = z - iz;
+
+    // Compute gradient weights
+    ix &= (NOISE_PERM_SIZE-1);
+    iy &= (NOISE_PERM_SIZE-1);
+    iz &= (NOISE_PERM_SIZE-1);
+    float w000 = Grad(ix,   iy,   iz,   dx,   dy,   dz);
+    float w100 = Grad(ix+1, iy,   iz,   dx-1, dy,   dz);
+    float w010 = Grad(ix,   iy+1, iz,   dx,   dy-1, dz);
+    float w110 = Grad(ix+1, iy+1, iz,   dx-1, dy-1, dz);
+    float w001 = Grad(ix,   iy,   iz+1, dx,   dy,   dz-1);
+    float w101 = Grad(ix+1, iy,   iz+1, dx-1, dy,   dz-1);
+    float w011 = Grad(ix,   iy+1, iz+1, dx,   dy-1, dz-1);
+    float w111 = Grad(ix+1, iy+1, iz+1, dx-1, dy-1, dz-1);
+
+    // Compute trilinear interpolation of weights
+    float wx = NoiseWeight(dx), wy = NoiseWeight(dy), wz = NoiseWeight(dz);
+    float x00 = Lerp(wx, w000, w100);
+    float x10 = Lerp(wx, w010, w110);
+    float x01 = Lerp(wx, w001, w101);
+    float x11 = Lerp(wx, w011, w111);
+    float y0 = Lerp(wy, x00, x10);
+    float y1 = Lerp(wy, x01, x11);
+    return Lerp(wz, y0, y1);
+}
+
+
+static float Turbulence(float x, float y, float z, int octaves) {
+    float omega = 0.6;
+
+    float sum = 0., lambda = 1., o = 1.;
+    for (int i = 0; i < octaves; ++i) {
+        sum += fabsf(o * Noise(lambda * x, lambda * y, lambda * z));
+        lambda *= 1.99f;
+        o *= omega;
+    }
+    return sum * 0.5;
+}
+
+
+void noise_serial(float x0, float y0, float x1, float y1,
+                  int width, int height, float output[])
+{
+    float dx = (x1 - x0) / width;
+    float dy = (y1 - y0) / height;
+
+    for (int j = 0; j < height; j++) {
+        for (int i = 0; i < width; ++i) {
+            float x = x0 + i * dx;
+            float y = y0 + j * dy;
+
+            int index = (j * width + i);
+            output[index] = Turbulence(x, y, 0.6, 8);
+        }
+    }
+}
+