samples: add blue noise generation demo.

.gitignore

@@ -79,6 +79,7 @@ _ReSharper.*
 # Our binaries
 demos/lol.js/lol.js
 doc/samples/benchsuite
+doc/samples/bluenoise
 doc/samples/btphystest
 doc/samples/meshviewer/meshviewer
 doc/samples/nacl_phystest

doc/samples/Makefile.am

@@ -7,9 +7,13 @@ bench: benchsuite$(EXEEXT)
 	./benchsuite$(EXEEXT)
 
 if BUILD_SAMPLES
-noinst_PROGRAMS = benchsuite btphystest nacl_phystest simplex
+noinst_PROGRAMS = bluenoise benchsuite btphystest nacl_phystest simplex
 endif
 
+bluenoise_SOURCES = bluenoise.cpp
+bluenoise_CPPFLAGS = $(AM_CPPFLAGS)
+bluenoise_DEPENDENCIES = @LOL_DEPS@
+
 benchsuite_SOURCES = benchsuite.cpp \
     benchmark/vector.cpp benchmark/half.cpp benchmark/trig.cpp \
     benchmark/real.cpp

doc/samples/bluenoise.cpp

@@ -0,0 +1,39 @@
+//
+//  bluenoise — create a N×N blue noise kernel
+//
+//  Copyright © 2016—2017 Sam Hocevar <sam@hocevar.net>
+//
+//  This program is free software. It comes without any warranty, to
+//  the extent permitted by applicable law. You can redistribute it
+//  and/or modify it under the terms of the Do What the Fuck You Want
+//  to Public License, Version 2, as published by the WTFPL Task Force.
+//  See http://www.wtfpl.net/ for more details.
+//
+
+#if HAVE_CONFIG_H
+#   include "config.h"
+#endif
+
+#include <lol/engine.h>
+
+using namespace lol;
+
+int main(int argc, char **argv)
+{
+    UNUSED(argc, argv);
+
+    ivec2 const size(64);
+    auto const &kernel = image::BlueNoiseKernel(size, ivec2(8));
+
+    image im(size.xy);
+    array2d<vec4> &data = im.Lock2D<PixelFormat::RGBA_F32>();
+
+    for (int j = 0; j < size.y; ++j)
+    for (int i = 0; i < size.x; ++i)
+        data[i][j] = vec4(vec3(kernel[i][j]), 1.0f);
+    im.Unlock2D(data);
+    im.Save("bluenoise.png");
+
+    return 0;
+}
+