From: Steinar H. Gunderson <sgunderson@bigfoot.com>
Date: Sat, 15 Mar 2014 02:12:53 +0000 (+0100)
Subject: Merge branch 'master' into epoxy
X-Git-Tag: 1.1~12^2~30
X-Git-Url: https://git.sesse.net/?p=movit;a=commitdiff_plain;h=daca930fb2f404e8800c35715f1fc5c4897d19fb;hp=6462d4df1986c76e363cf21ee0c7734d1b312635

Merge branch 'master' into epoxy
---

diff --git a/Makefile.in b/Makefile.in
index 8164e38..cefbf78 100644
--- a/Makefile.in
+++ b/Makefile.in
@@ -8,13 +8,17 @@ datarootdir = @datarootdir@
 datadir = @datadir@
 top_builddir = @top_builddir@
 with_demo_app = @with_demo_app@
+with_SDL2 = @with_SDL2@
 with_coverage = @with_coverage@
 
 CC=@CC@
 CXX=@CXX@
-CXXFLAGS=-Wall @CXXFLAGS@ -I$(GTEST_DIR)/include @Eigen3_CFLAGS@ @GLEW_CFLAGS@
-LDFLAGS=@GLEW_LIBS@ @SDL_LIBS@ -lpthread
-DEMO_LDLIBS=@SDL_image_LIBS@ -lrt -lpthread @libpng_LIBS@
+CXXFLAGS=-Wall @CXXFLAGS@ -I$(GTEST_DIR)/include @SDL2_CFLAGS@ @SDL_CFLAGS@ @Eigen3_CFLAGS@ @epoxy_CFLAGS@
+ifeq ($(with_SDL2),yes)
+CXXFLAGS += -DHAVE_SDL2
+endif
+LDFLAGS=@epoxy_LIBS@ @SDL2_LIBS@ @SDL_LIBS@ -lpthread
+DEMO_LDLIBS=@SDL2_image_LIBS@ @SDL_image_LIBS@ -lrt -lpthread @libpng_LIBS@
 SHELL=@SHELL@
 LIBTOOL=@LIBTOOL@ --tag=CXX
 RANLIB=ranlib
diff --git a/README b/README
index 3f29bea..81bb4c9 100644
--- a/README
+++ b/README
@@ -21,12 +21,13 @@ OK, you need
   works fine on Linux and OS X, and Movit is not very POSIX-bound.)
 * GNU Make.
 * A GPU capable of running GLSL fragment shaders,
-  process floating-point textures, and a few other things. If your machine
-  is less than five years old _and you have the appropriate drivers_,
-  you're home free.
+  processing floating-point textures, and a few other things (all are
+  part of OpenGL 3.0 or newer, although most OpenGL 2.0 cards also
+  have what's needed through extensions). If your machine is less than five
+  years old _and you have the appropriate drivers_, you're home free.
 * The [Eigen 3] and [Google Test] libraries. (The library itself
   depends only on the former, but you probably want to run the unit tests.)
-* The [GLEW] library, for dealing with OpenGL extensions on various
+* The [epoxy] library, for dealing with OpenGL extensions on various
   platforms.
 
 Movit has been tested with Intel GPUs with the Mesa drivers
@@ -53,7 +54,8 @@ all research-grade problems, and Movit is currently not there.)
 TL;DR, but I am interested in a programming example instead
 ===========================================================
 
-Assuming you have an OpenGL context already set up:
+Assuming you have an OpenGL context already set up (currently you need
+a classic OpenGL context; a GL 3.2+ core context won't do):
 
 <code>
   using namespace movit;
diff --git a/alpha_division_effect_test.cpp b/alpha_division_effect_test.cpp
index faa8b17..549b569 100644
--- a/alpha_division_effect_test.cpp
+++ b/alpha_division_effect_test.cpp
@@ -1,6 +1,6 @@
 // Unit tests for AlphaDivisionEffect.
 
-#include <GL/glew.h>
+#include <epoxy/gl.h>
 #include "gtest/gtest.h"
 #include "image_format.h"
 #include "test_util.h"
diff --git a/alpha_multiplication_effect_test.cpp b/alpha_multiplication_effect_test.cpp
index c63c0a3..2aa9b6d 100644
--- a/alpha_multiplication_effect_test.cpp
+++ b/alpha_multiplication_effect_test.cpp
@@ -1,6 +1,6 @@
 // Unit tests for AlphaMultiplicationEffect.
 
-#include <GL/glew.h>
+#include <epoxy/gl.h>
 
 #include "effect_chain.h"
 #include "gtest/gtest.h"
diff --git a/blur_effect.cpp b/blur_effect.cpp
index 9397ca4..b0327e2 100644
--- a/blur_effect.cpp
+++ b/blur_effect.cpp
@@ -1,4 +1,4 @@
-#include <GL/glew.h>
+#include <epoxy/gl.h>
 #include <assert.h>
 #include <math.h>
 #include <algorithm>
diff --git a/blur_effect.h b/blur_effect.h
index d97f5bd..ad269f5 100644
--- a/blur_effect.h
+++ b/blur_effect.h
@@ -9,7 +9,7 @@
 // which is what the user is intended to use, instantiates two copies of
 // SingleBlurPassEffect behind the scenes).
 
-#include <GL/glew.h>
+#include <epoxy/gl.h>
 #include <assert.h>
 #include <stddef.h>
 #include <string>
diff --git a/blur_effect_test.cpp b/blur_effect_test.cpp
index 1ef479e..fb4e025 100644
--- a/blur_effect_test.cpp
+++ b/blur_effect_test.cpp
@@ -1,5 +1,5 @@
 // Unit tests for BlurEffect.
-#include <GL/glew.h>
+#include <epoxy/gl.h>
 #include <math.h>
 #include <string.h>
 
diff --git a/colorspace_conversion_effect_test.cpp b/colorspace_conversion_effect_test.cpp
index cf8aad7..1395140 100644
--- a/colorspace_conversion_effect_test.cpp
+++ b/colorspace_conversion_effect_test.cpp
@@ -1,6 +1,6 @@
 // Unit tests for ColorspaceConversionEffect.
 
-#include <GL/glew.h>
+#include <epoxy/gl.h>
 
 #include "colorspace_conversion_effect.h"
 #include "gtest/gtest.h"
diff --git a/complex_modulate_effect.cpp b/complex_modulate_effect.cpp
index 7048608..656de3a 100644
--- a/complex_modulate_effect.cpp
+++ b/complex_modulate_effect.cpp
@@ -1,4 +1,4 @@
-#include <GL/glew.h>
+#include <epoxy/gl.h>
 
 #include "complex_modulate_effect.h"
 #include "effect_chain.h"
diff --git a/complex_modulate_effect.h b/complex_modulate_effect.h
index 52de229..fd4eb8b 100644
--- a/complex_modulate_effect.h
+++ b/complex_modulate_effect.h
@@ -21,7 +21,7 @@
 // don't care about the actual FFT result, just that the convolution property
 // holds.)
 
-#include <GL/glew.h>
+#include <epoxy/gl.h>
 #include <string>
 
 #include "effect.h"
diff --git a/complex_modulate_effect_test.cpp b/complex_modulate_effect_test.cpp
index 8c49d8a..b505d86 100644
--- a/complex_modulate_effect_test.cpp
+++ b/complex_modulate_effect_test.cpp
@@ -1,6 +1,6 @@
 // Unit tests for ComplexModulateEffect.
 
-#include <GL/glew.h>
+#include <epoxy/gl.h>
 
 #include "effect_chain.h"
 #include "gtest/gtest.h"
diff --git a/configure.ac b/configure.ac
index 5e03234..f911746 100644
--- a/configure.ac
+++ b/configure.ac
@@ -7,17 +7,26 @@ AC_CONFIG_SRCDIR(effect.cpp)
 AC_PROG_CC
 AC_PROG_CXX
 PKG_CHECK_MODULES([Eigen3], [eigen3])
-PKG_CHECK_MODULES([GLEW], [glew])
+PKG_CHECK_MODULES([epoxy], [epoxy])
 
-# Needed for unit tests and the demo app.
-PKG_CHECK_MODULES([SDL], [sdl])
+# Needed for unit tests and the demo app. We prefer SDL2 if possible,
+# but can also use classic SDL.
+with_SDL2=no
+with_demo_app=yes
+PKG_CHECK_MODULES([SDL2], [sdl2], [with_SDL2=yes], [
+  PKG_CHECK_MODULES([SDL], [sdl])
+])
 
 # These are only needed for the demo app.
-with_demo_app=yes
-PKG_CHECK_MODULES([SDL_image], [SDL_image], [], [with_demo_app=no; AC_MSG_WARN([SDL_image not found, demo program will not be built])])
+if test $with_SDL2 = "yes"; then
+  PKG_CHECK_MODULES([SDL2_image], [SDL2_image], [], [with_demo_app=no; AC_MSG_WARN([SDL2_image not found, demo program will not be built])])
+else
+  PKG_CHECK_MODULES([SDL_image], [SDL_image], [], [with_demo_app=no; AC_MSG_WARN([SDL_image not found, demo program will not be built])])
+fi
 PKG_CHECK_MODULES([libpng], [libpng12], [], [with_demo_app=no; AC_MSG_WARN([libpng12 not found, demo program will not be built])])
 
 AC_SUBST([with_demo_app])
+AC_SUBST([with_SDL2])
 
 with_coverage=no
 AC_ARG_ENABLE([coverage], [  --enable-coverage       build with information needed to compute test coverage], [with_coverage=yes])
diff --git a/deconvolution_sharpen_effect.cpp b/deconvolution_sharpen_effect.cpp
index f564b68..c4ad5cd 100644
--- a/deconvolution_sharpen_effect.cpp
+++ b/deconvolution_sharpen_effect.cpp
@@ -4,7 +4,7 @@
 
 #include <Eigen/Dense>
 #include <Eigen/Cholesky>
-#include <GL/glew.h>
+#include <epoxy/gl.h>
 #include <assert.h>
 #include <math.h>
 #include <stdio.h>
diff --git a/deconvolution_sharpen_effect.h b/deconvolution_sharpen_effect.h
index e4cc9a5..1f68071 100644
--- a/deconvolution_sharpen_effect.h
+++ b/deconvolution_sharpen_effect.h
@@ -19,7 +19,7 @@
 //
 //   Jain, Anil K.: “Fundamentals of Digital Image Processing”, Prentice Hall, 1988.
 
-#include <GL/glew.h>
+#include <epoxy/gl.h>
 #include <Eigen/Dense>
 #include <string>
 
diff --git a/deconvolution_sharpen_effect_test.cpp b/deconvolution_sharpen_effect_test.cpp
index 8829b9d..ab1a5a4 100644
--- a/deconvolution_sharpen_effect_test.cpp
+++ b/deconvolution_sharpen_effect_test.cpp
@@ -1,6 +1,6 @@
 // Unit tests for DeconvolutionSharpenEffect.
 
-#include <GL/glew.h>
+#include <epoxy/gl.h>
 #include <math.h>
 #include <stdlib.h>
 
diff --git a/demo.cpp b/demo.cpp
index 845a776..c9b46ea 100644
--- a/demo.cpp
+++ b/demo.cpp
@@ -4,7 +4,17 @@
 #define WIDTH 1280
 #define HEIGHT 720
 
-#include <GL/glew.h>
+#include <epoxy/gl.h>
+
+#ifdef HAVE_SDL2
+#include <SDL2/SDL.h>
+#include <SDL2/SDL_error.h>
+#include <SDL2/SDL_events.h>
+#include <SDL2/SDL_image.h>
+#include <SDL2/SDL_keyboard.h>
+#include <SDL2/SDL_mouse.h>
+#include <SDL2/SDL_video.h>
+#else
 #include <SDL/SDL.h>
 #include <SDL/SDL_error.h>
 #include <SDL/SDL_events.h>
@@ -13,6 +23,8 @@
 #include <SDL/SDL_keysym.h>
 #include <SDL/SDL_mouse.h>
 #include <SDL/SDL_video.h>
+#endif
+
 #include <assert.h>
 #include <features.h>
 #include <math.h>
@@ -121,9 +133,11 @@ unsigned char *load_image(const char *filename, unsigned *w, unsigned *h)
 	rgba_fmt.Gshift = 8;
 	rgba_fmt.Bshift = 0;
 	rgba_fmt.Ashift = 24;
-	
+
+#ifndef HAVE_SDL2
 	rgba_fmt.colorkey = 0;
 	rgba_fmt.alpha = 255;
+#endif
 
 	SDL_Surface *converted = SDL_ConvertSurface(img, &rgba_fmt, SDL_SWSURFACE);
 
@@ -175,8 +189,19 @@ int main(int argc, char **argv)
 	SDL_GL_SetAttribute(SDL_GL_DEPTH_SIZE, 0);
 	SDL_GL_SetAttribute(SDL_GL_STENCIL_SIZE, 0);
 	SDL_GL_SetAttribute(SDL_GL_DOUBLEBUFFER, 1);
+
+#ifdef HAVE_SDL2
+	SDL_Window *window = SDL_CreateWindow("OpenGL window",
+		SDL_WINDOWPOS_UNDEFINED,
+		SDL_WINDOWPOS_UNDEFINED,
+		WIDTH, HEIGHT,
+		SDL_WINDOW_OPENGL);
+	SDL_GLContext context = SDL_GL_CreateContext(window);
+	assert(context != NULL);
+#else
 	SDL_SetVideoMode(WIDTH, HEIGHT, 0, SDL_OPENGL);
 	SDL_WM_SetCaption("OpenGL window", NULL);
+#endif
 
 	CHECK(init_movit(".", MOVIT_DEBUG_ON));
 	printf("GPU texture subpixel precision: about %.1f bits\n",
@@ -288,7 +313,11 @@ int main(int argc, char **argv)
 		draw_saturation_bar(0.75f, blur_radius / 100.0f);
 		draw_saturation_bar(0.80f, blurred_mix_amount);
 
+#ifdef HAVE_SDL2
+		SDL_GL_SwapWindow(window);
+#else
 		SDL_GL_SwapBuffers();
+#endif
 		check_error();
 
 		glBindBuffer(GL_PIXEL_PACK_BUFFER_ARB, pbo);
diff --git a/diffusion_effect.h b/diffusion_effect.h
index 2c31e4a..82eda93 100644
--- a/diffusion_effect.h
+++ b/diffusion_effect.h
@@ -12,7 +12,7 @@
 // where we first blur the picture, and then overlay it on the original
 // using the original as a matte.
 
-#include <GL/glew.h>
+#include <epoxy/gl.h>
 #include <assert.h>
 #include <string>
 
diff --git a/diffusion_effect_test.cpp b/diffusion_effect_test.cpp
index 7e50a04..e58c0de 100644
--- a/diffusion_effect_test.cpp
+++ b/diffusion_effect_test.cpp
@@ -1,6 +1,6 @@
 // Unit tests for DiffusionEffect.
 
-#include <GL/glew.h>
+#include <epoxy/gl.h>
 
 #include "diffusion_effect.h"
 #include "effect_chain.h"
diff --git a/dither_effect.cpp b/dither_effect.cpp
index 72a38de..17c577d 100644
--- a/dither_effect.cpp
+++ b/dither_effect.cpp
@@ -1,4 +1,4 @@
-#include <GL/glew.h>
+#include <epoxy/gl.h>
 #include <assert.h>
 #include <stdio.h>
 #include <algorithm>
diff --git a/dither_effect.h b/dither_effect.h
index 20fb025..9818603 100644
--- a/dither_effect.h
+++ b/dither_effect.h
@@ -43,7 +43,7 @@
 // like many LCD monitors do, but it starts to get very hairy, again, for limited gains.)
 // The dither is also deterministic across runs.
 
-#include <GL/glew.h>
+#include <epoxy/gl.h>
 #include <string>
 
 #include "effect.h"
diff --git a/dither_effect_test.cpp b/dither_effect_test.cpp
index 8801aa0..210a2e7 100644
--- a/dither_effect_test.cpp
+++ b/dither_effect_test.cpp
@@ -1,6 +1,6 @@
 // Unit tests for DitherEffect.
 
-#include <GL/glew.h>
+#include <epoxy/gl.h>
 #include <math.h>
 
 #include "effect_chain.h"
diff --git a/effect.cpp b/effect.cpp
index eded11a..fb66514 100644
--- a/effect.cpp
+++ b/effect.cpp
@@ -1,4 +1,4 @@
-#include <GL/glew.h>
+#include <epoxy/gl.h>
 #include <assert.h>
 #include <stdio.h>
 #include <string.h>
diff --git a/effect.h b/effect.h
index 14cbe30..9d95705 100644
--- a/effect.h
+++ b/effect.h
@@ -10,7 +10,7 @@
 // effect instance; use the macro PREFIX() around your identifiers to
 // automatically prepend that prefix.
 
-#include <GL/glew.h>
+#include <epoxy/gl.h>
 #include <assert.h>
 #include <stddef.h>
 #include <map>
diff --git a/effect_chain.cpp b/effect_chain.cpp
index c886155..ef44024 100644
--- a/effect_chain.cpp
+++ b/effect_chain.cpp
@@ -1,6 +1,6 @@
 #define GL_GLEXT_PROTOTYPES 1
 
-#include <GL/glew.h>
+#include <epoxy/gl.h>
 #include <assert.h>
 #include <locale.h>
 #include <math.h>
diff --git a/effect_chain.h b/effect_chain.h
index cbc1221..02906fe 100644
--- a/effect_chain.h
+++ b/effect_chain.h
@@ -17,7 +17,7 @@
 // the EffectChain holds textures and other OpenGL objects that are tied to the
 // context.
 
-#include <GL/glew.h>
+#include <epoxy/gl.h>
 #include <stdio.h>
 #include <map>
 #include <set>
diff --git a/effect_chain_test.cpp b/effect_chain_test.cpp
index b1f0815..aabcc33 100644
--- a/effect_chain_test.cpp
+++ b/effect_chain_test.cpp
@@ -2,7 +2,7 @@
 //
 // Note that this also contains the tests for some of the simpler effects.
 
-#include <GL/glew.h>
+#include <epoxy/gl.h>
 #include <assert.h>
 
 #include "effect.h"
diff --git a/effect_util.cpp b/effect_util.cpp
index 35a94a7..b671620 100644
--- a/effect_util.cpp
+++ b/effect_util.cpp
@@ -1,4 +1,4 @@
-#include <GL/glew.h>
+#include <epoxy/gl.h>
 #include <Eigen/Core>
 #include <stddef.h>
 #include <string>
diff --git a/effect_util.h b/effect_util.h
index 65bd315..da0f95a 100644
--- a/effect_util.h
+++ b/effect_util.h
@@ -4,7 +4,7 @@
 // Utilities that are often useful for implementing Effect instances,
 // but don't need to be included from effect.h.
 
-#include <GL/glew.h>
+#include <epoxy/gl.h>
 #include <assert.h>
 #include <stddef.h>
 #include <Eigen/Core>
diff --git a/fft_pass_effect.cpp b/fft_pass_effect.cpp
index 4069be9..ee0b983 100644
--- a/fft_pass_effect.cpp
+++ b/fft_pass_effect.cpp
@@ -1,4 +1,4 @@
-#include <GL/glew.h>
+#include <epoxy/gl.h>
 #include <math.h>
 
 #include "effect_chain.h"
diff --git a/fft_pass_effect.h b/fft_pass_effect.h
index 460a946..90e88bc 100644
--- a/fft_pass_effect.h
+++ b/fft_pass_effect.h
@@ -50,7 +50,7 @@
 // scaling), and as fp16 has quite limited range at times, this can be relevant
 // on some GPUs for larger sizes.
 
-#include <GL/glew.h>
+#include <epoxy/gl.h>
 #include <assert.h>
 #include <stdio.h>
 #include <string>
diff --git a/fft_pass_effect_test.cpp b/fft_pass_effect_test.cpp
index 284aa5f..015847a 100644
--- a/fft_pass_effect_test.cpp
+++ b/fft_pass_effect_test.cpp
@@ -3,11 +3,11 @@
 #include <math.h>
 #include <stdlib.h>
 #include <string.h>
+#include <epoxy/gl.h>
+#include <gtest/gtest.h>
 
 #include "effect_chain.h"
 #include "fft_pass_effect.h"
-#include "glew.h"
-#include "gtest/gtest.h"
 #include "image_format.h"
 #include "multiply_effect.h"
 #include "test_util.h"
diff --git a/flat_input.cpp b/flat_input.cpp
index 46370d6..55c65cc 100644
--- a/flat_input.cpp
+++ b/flat_input.cpp
@@ -1,6 +1,6 @@
 #include <string.h>
 #include <assert.h>
-#include <GL/glew.h>
+#include <epoxy/gl.h>
 
 #include "effect_util.h"
 #include "flat_input.h"
diff --git a/flat_input.h b/flat_input.h
index 965e34d..8ac98ba 100644
--- a/flat_input.h
+++ b/flat_input.h
@@ -1,7 +1,7 @@
 #ifndef _MOVIT_FLAT_INPUT_H
 #define _MOVIT_FLAT_INPUT_H 1
 
-#include <GL/glew.h>
+#include <epoxy/gl.h>
 #include <assert.h>
 #include <string>
 
diff --git a/flat_input_test.cpp b/flat_input_test.cpp
index 58d9eb9..397cae3 100644
--- a/flat_input_test.cpp
+++ b/flat_input_test.cpp
@@ -1,6 +1,6 @@
 // Unit tests for FlatInput.
 
-#include <GL/glew.h>
+#include <epoxy/gl.h>
 #include <stddef.h>
 
 #include "effect_chain.h"
diff --git a/gamma_compression_effect.h b/gamma_compression_effect.h
index 83208cf..ee3985f 100644
--- a/gamma_compression_effect.h
+++ b/gamma_compression_effect.h
@@ -9,7 +9,7 @@
 // Note that Movit's internal formats generally do not have enough accuracy
 // for 12-bit input or output.
 
-#include <GL/glew.h>
+#include <epoxy/gl.h>
 #include <string>
 
 #include "effect.h"
diff --git a/gamma_compression_effect_test.cpp b/gamma_compression_effect_test.cpp
index 41fe776..6efbdea 100644
--- a/gamma_compression_effect_test.cpp
+++ b/gamma_compression_effect_test.cpp
@@ -5,7 +5,7 @@
 // However, the accuracy tests are somewhat simpler, since we
 // only need to care about absolute errors and not relative.
 
-#include <GL/glew.h>
+#include <epoxy/gl.h>
 #include <math.h>
 
 #include "gtest/gtest.h"
diff --git a/gamma_expansion_effect.h b/gamma_expansion_effect.h
index b5381ad..81f42d1 100644
--- a/gamma_expansion_effect.h
+++ b/gamma_expansion_effect.h
@@ -9,7 +9,7 @@
 // Note that Movit's internal formats generally do not have enough accuracy
 // for 12-bit input or output.
 
-#include <GL/glew.h>
+#include <epoxy/gl.h>
 #include <string>
 
 #include "effect.h"
diff --git a/gamma_expansion_effect_test.cpp b/gamma_expansion_effect_test.cpp
index d1d6d2a..499a0d4 100644
--- a/gamma_expansion_effect_test.cpp
+++ b/gamma_expansion_effect_test.cpp
@@ -1,6 +1,6 @@
 // Unit tests for GammaExpansionEffect.
 
-#include <GL/glew.h>
+#include <epoxy/gl.h>
 #include <math.h>
 
 #include "gamma_expansion_effect.h"
diff --git a/glow_effect.h b/glow_effect.h
index af83307..2a2af16 100644
--- a/glow_effect.h
+++ b/glow_effect.h
@@ -4,7 +4,7 @@
 // Glow: Cut out the highlights of the image (everything above a certain threshold),
 // blur them, and overlay them onto the original image.
 
-#include <GL/glew.h>
+#include <epoxy/gl.h>
 #include <assert.h>
 #include <string>
 
diff --git a/glow_effect_test.cpp b/glow_effect_test.cpp
index 11083a9..174937b 100644
--- a/glow_effect_test.cpp
+++ b/glow_effect_test.cpp
@@ -1,6 +1,6 @@
 // Unit tests for GlowEffect.
 
-#include <GL/glew.h>
+#include <epoxy/gl.h>
 #include <math.h>
 
 #include "effect_chain.h"
diff --git a/gtest_sdl_main.cpp b/gtest_sdl_main.cpp
index 39027e6..cd68777 100644
--- a/gtest_sdl_main.cpp
+++ b/gtest_sdl_main.cpp
@@ -1,8 +1,14 @@
 #define GTEST_HAS_EXCEPTIONS 0
 
+#ifdef HAVE_SDL2
+#include <SDL2/SDL.h>
+#include <SDL2/SDL_error.h>
+#include <SDL2/SDL_video.h>
+#else
 #include <SDL/SDL.h>
 #include <SDL/SDL_error.h>
 #include <SDL/SDL_video.h>
+#endif
 #include <stdio.h>
 #include <stdlib.h>
 
@@ -17,8 +23,28 @@ int main(int argc, char **argv) {
 	SDL_GL_SetAttribute(SDL_GL_DEPTH_SIZE, 0);
 	SDL_GL_SetAttribute(SDL_GL_STENCIL_SIZE, 0);
 	SDL_GL_SetAttribute(SDL_GL_DOUBLEBUFFER, 1);
+
+#ifdef HAVE_SDL2
+	// You can uncomment this if you want to try a core context.
+	// For Mesa, you can get the same effect by doing
+	//
+	//   export MESA_GL_VERSION_OVERRIDE=3.1FC
+	//
+	// before running tests.
+//	SDL_GL_SetAttribute(SDL_GL_CONTEXT_PROFILE_MASK, SDL_GL_CONTEXT_PROFILE_CORE);
+//	SDL_GL_SetAttribute(SDL_GL_CONTEXT_MAJOR_VERSION, 3);
+//	SDL_GL_SetAttribute(SDL_GL_CONTEXT_MINOR_VERSION, 2);
+	SDL_Window *window = SDL_CreateWindow("OpenGL window for unit test",
+		SDL_WINDOWPOS_UNDEFINED,
+		SDL_WINDOWPOS_UNDEFINED,
+		32, 32,
+		SDL_WINDOW_OPENGL);
+	SDL_GLContext context = SDL_GL_CreateContext(window);
+	assert(context != NULL);
+#else
 	SDL_SetVideoMode(32, 32, 0, SDL_OPENGL);
 	SDL_WM_SetCaption("OpenGL window for unit test", NULL);
+#endif
 
 	testing::InitGoogleTest(&argc, argv);
 	int err = RUN_ALL_TESTS();
diff --git a/init.cpp b/init.cpp
index 13a86df..671c507 100644
--- a/init.cpp
+++ b/init.cpp
@@ -1,4 +1,4 @@
-#include <GL/glew.h>
+#include <epoxy/gl.h>
 #include <assert.h>
 #include <stddef.h>
 #include <algorithm>
@@ -278,32 +278,43 @@ void measure_roundoff_problems()
 bool check_extensions()
 {
 	// We fundamentally need FBOs and floating-point textures.
-	if (!glewIsSupported("GL_ARB_framebuffer_object")) return false;
-	if (!glewIsSupported("GL_ARB_texture_float")) return false;
+	// FBOs are covered by OpenGL 1.5, and are not an extension there.
+	// Floating-point textures are part of OpenGL 3.0 and newer.
+	if (epoxy_gl_version() < 15 &&
+	    !epoxy_has_gl_extension("GL_ARB_framebuffer_object")) return false;
+	if (epoxy_gl_version() < 30 &&
+	    !epoxy_has_gl_extension("GL_ARB_texture_float")) return false;
 
 	// We assume that we can use non-power-of-two textures without restrictions.
-	if (!glewIsSupported("GL_ARB_texture_non_power_of_two")) return false;
+	if (epoxy_gl_version() < 20 &&
+	    !epoxy_has_gl_extension("GL_ARB_texture_non_power_of_two")) return false;
 
 	// We also need GLSL fragment shaders.
-	if (!glewIsSupported("GL_ARB_fragment_shader")) return false;
-	if (!glewIsSupported("GL_ARB_shading_language_100")) return false;
+	if (epoxy_gl_version() < 20) {
+		if (!epoxy_has_gl_extension("GL_ARB_fragment_shader")) return false;
+		if (!epoxy_has_gl_extension("GL_ARB_shading_language_100")) return false;
+	}
 
 	// FlatInput and YCbCrInput uses PBOs. (They could in theory do without,
 	// but no modern card would really not provide it.)
-	if (!glewIsSupported("GL_ARB_pixel_buffer_object")) return false;
+	if (epoxy_gl_version() < 21 &&
+	    !epoxy_has_gl_extension("GL_ARB_pixel_buffer_object")) return false;
 
 	// ResampleEffect uses RG textures to encode a two-component LUT.
-	if (!glewIsSupported("GL_ARB_texture_rg")) return false;
+	if (epoxy_gl_version() < 30 &&
+	    !epoxy_has_gl_extension("GL_ARB_texture_rg")) return false;
 
 	// sRGB texture decode would be nice, but are not mandatory
 	// (GammaExpansionEffect can do the same thing if needed).
-	movit_srgb_textures_supported = glewIsSupported("GL_EXT_texture_sRGB");
+	movit_srgb_textures_supported =
+		(epoxy_gl_version() >= 21 || epoxy_has_gl_extension("GL_EXT_texture_sRGB"));
 
 	// We may want to use round() at the end of the final shader,
 	// if supported. We need either GLSL 1.30 or this extension to do that,
 	// and 1.30 brings with it other things that we don't want to demand
 	// for now.
-	movit_shader_rounding_supported = glewIsSupported("GL_EXT_gpu_shader4");
+	movit_shader_rounding_supported =
+		(epoxy_gl_version() >= 30 || epoxy_has_gl_extension("GL_EXT_gpu_shader4"));
 
 	return true;
 }
@@ -319,11 +330,6 @@ bool init_movit(const string& data_directory, MovitDebugLevel debug_level)
 	movit_data_directory = new string(data_directory);
 	movit_debug_level = debug_level;
 
-	GLenum err = glewInit();
-	if (err != GLEW_OK) {
-		return false;
-	}
-
 	// geez	
 	glPixelStorei(GL_PACK_ALIGNMENT, 1);
 	glPixelStorei(GL_UNPACK_ALIGNMENT, 1);
diff --git a/lift_gamma_gain_effect.cpp b/lift_gamma_gain_effect.cpp
index e9832f4..60cd7df 100644
--- a/lift_gamma_gain_effect.cpp
+++ b/lift_gamma_gain_effect.cpp
@@ -1,4 +1,4 @@
-#include <GL/glew.h>
+#include <epoxy/gl.h>
 #include <math.h>
 
 #include "effect_util.h"
diff --git a/lift_gamma_gain_effect.h b/lift_gamma_gain_effect.h
index b500772..c93724d 100644
--- a/lift_gamma_gain_effect.h
+++ b/lift_gamma_gain_effect.h
@@ -20,7 +20,7 @@
 // Also, gamma is a case where we would not want premultiplied alpha.
 // Thus, we have to divide away alpha first, and then re-multiply it back later.
 
-#include <GL/glew.h>
+#include <epoxy/gl.h>
 #include <string>
 
 #include "effect.h"
diff --git a/lift_gamma_gain_effect_test.cpp b/lift_gamma_gain_effect_test.cpp
index 612901f..1be2847 100644
--- a/lift_gamma_gain_effect_test.cpp
+++ b/lift_gamma_gain_effect_test.cpp
@@ -1,6 +1,6 @@
 // Unit tests for LiftGammaGainEffect.
 
-#include <GL/glew.h>
+#include <epoxy/gl.h>
 
 #include "effect_chain.h"
 #include "gtest/gtest.h"
diff --git a/luma_mix_effect_test.cpp b/luma_mix_effect_test.cpp
index 618b733..4a506f5 100644
--- a/luma_mix_effect_test.cpp
+++ b/luma_mix_effect_test.cpp
@@ -1,6 +1,6 @@
 // Unit tests for LumaMixEffect.
 
-#include <GL/glew.h>
+#include <epoxy/gl.h>
 
 #include "effect_chain.h"
 #include "gtest/gtest.h"
diff --git a/mix_effect_test.cpp b/mix_effect_test.cpp
index 8432f1e..7e54ca5 100644
--- a/mix_effect_test.cpp
+++ b/mix_effect_test.cpp
@@ -1,6 +1,6 @@
 // Unit tests for MixEffect.
 
-#include <GL/glew.h>
+#include <epoxy/gl.h>
 
 #include "effect_chain.h"
 #include "gtest/gtest.h"
diff --git a/movit.pc.in b/movit.pc.in
index f990618..6069a06 100644
--- a/movit.pc.in
+++ b/movit.pc.in
@@ -13,5 +13,5 @@ Description: Movit is a library for high-quality, high-performance video filters
 Version: git
 Requires:
 Conflicts:
-Libs: -lmovit @GLEW_LIBS@
-Cflags: -I${includedir}/movit @Eigen3_CFLAGS@ @GLEW_CFLAGS@
+Libs: -lmovit @epoxy_LIBS@
+Cflags: -I${includedir}/movit @Eigen3_CFLAGS@ @epoxy_CFLAGS@
diff --git a/multiply_effect.h b/multiply_effect.h
index 50612fc..92e98e3 100644
--- a/multiply_effect.h
+++ b/multiply_effect.h
@@ -6,7 +6,7 @@
 // sending it through OverlayEffect, e.g. with R=G=B=A=0.3 to get 30% alpha
 // (remember, alpha is premultiplied).
 
-#include <GL/glew.h>
+#include <epoxy/gl.h>
 #include <string>
 
 #include "effect.h"
diff --git a/overlay_effect_test.cpp b/overlay_effect_test.cpp
index 0a9682e..47c39b5 100644
--- a/overlay_effect_test.cpp
+++ b/overlay_effect_test.cpp
@@ -1,6 +1,6 @@
 // Unit tests for OverlayEffect.
 
-#include <GL/glew.h>
+#include <epoxy/gl.h>
 
 #include "effect_chain.h"
 #include "gtest/gtest.h"
diff --git a/padding_effect.cpp b/padding_effect.cpp
index 15381a3..f576baa 100644
--- a/padding_effect.cpp
+++ b/padding_effect.cpp
@@ -1,4 +1,4 @@
-#include <GL/glew.h>
+#include <epoxy/gl.h>
 #include <assert.h>
 
 #include "effect_util.h"
diff --git a/padding_effect.h b/padding_effect.h
index 3bd4aac..901f892 100644
--- a/padding_effect.h
+++ b/padding_effect.h
@@ -12,7 +12,7 @@
 // You may not change it after calling finalize(), since that could change the
 // graph (need_linear_light() etc. depend on the border color you choose).
 
-#include <GL/glew.h>
+#include <epoxy/gl.h>
 #include <string>
 
 #include "effect.h"
diff --git a/padding_effect_test.cpp b/padding_effect_test.cpp
index 767f3e8..dd836ea 100644
--- a/padding_effect_test.cpp
+++ b/padding_effect_test.cpp
@@ -1,6 +1,6 @@
 // Unit tests for AlphaMultiplicationEffect.
 
-#include <GL/glew.h>
+#include <epoxy/gl.h>
 #include <stddef.h>
 
 #include "effect_chain.h"
diff --git a/resample_effect.cpp b/resample_effect.cpp
index a677487..50b7c6b 100644
--- a/resample_effect.cpp
+++ b/resample_effect.cpp
@@ -1,7 +1,7 @@
 // Three-lobed Lanczos, the most common choice.
 #define LANCZOS_RADIUS 3.0
 
-#include <GL/glew.h>
+#include <epoxy/gl.h>
 #include <assert.h>
 #include <limits.h>
 #include <math.h>
diff --git a/resample_effect.h b/resample_effect.h
index 44587bf..f0112b3 100644
--- a/resample_effect.h
+++ b/resample_effect.h
@@ -15,7 +15,7 @@
 // which is what the user is intended to use, instantiates two copies of
 // SingleResamplePassEffect behind the scenes).
 
-#include <GL/glew.h>
+#include <epoxy/gl.h>
 #include <assert.h>
 #include <stddef.h>
 #include <string>
diff --git a/resample_effect_test.cpp b/resample_effect_test.cpp
index 211e6d1..95c2bcf 100644
--- a/resample_effect_test.cpp
+++ b/resample_effect_test.cpp
@@ -1,12 +1,11 @@
 // Unit tests for ResampleEffect.
 
-#include <GL/glew.h>
+#include <epoxy/gl.h>
+#include <gtest/gtest.h>
 #include <math.h>
 
 #include "effect_chain.h"
 #include "flat_input.h"
-#include "glew.h"
-#include "gtest/gtest.h"
 #include "image_format.h"
 #include "resample_effect.h"
 #include "test_util.h"
diff --git a/resource_pool.cpp b/resource_pool.cpp
index 72b3095..b515769 100644
--- a/resource_pool.cpp
+++ b/resource_pool.cpp
@@ -6,8 +6,8 @@
 #include <map>
 #include <string>
 #include <utility>
+#include <epoxy/gl.h>
 
-#include "glew.h"
 #include "init.h"
 #include "resource_pool.h"
 #include "util.h"
diff --git a/resource_pool.h b/resource_pool.h
index ea56d01..d8d8cec 100644
--- a/resource_pool.h
+++ b/resource_pool.h
@@ -16,7 +16,7 @@
 // safely called from multiple threads at the same time, provided they have
 // separate (but sharing) OpenGL contexts.
 
-#include <GL/glew.h>
+#include <epoxy/gl.h>
 #include <pthread.h>
 #include <stddef.h>
 #include <list>
diff --git a/sandbox_effect.cpp b/sandbox_effect.cpp
index 76e1f5c..1ec093d 100644
--- a/sandbox_effect.cpp
+++ b/sandbox_effect.cpp
@@ -1,4 +1,4 @@
-#include <GL/glew.h>
+#include <epoxy/gl.h>
 
 #include "sandbox_effect.h"
 #include "util.h"
diff --git a/sandbox_effect.h b/sandbox_effect.h
index f06b2ef..25c7992 100644
--- a/sandbox_effect.h
+++ b/sandbox_effect.h
@@ -8,7 +8,7 @@
 // throwaway code. When you're happy, you can do a bit of search and replace
 // to give it a proper name and its own place in the build system.
 
-#include <GL/glew.h>
+#include <epoxy/gl.h>
 #include <string>
 
 #include "effect.h"
diff --git a/saturation_effect_test.cpp b/saturation_effect_test.cpp
index 941df99..6a711a4 100644
--- a/saturation_effect_test.cpp
+++ b/saturation_effect_test.cpp
@@ -1,6 +1,6 @@
 // Unit tests for SaturationEffect.
 
-#include <GL/glew.h>
+#include <epoxy/gl.h>
 
 #include "effect_chain.h"
 #include "gtest/gtest.h"
diff --git a/slice_effect.cpp b/slice_effect.cpp
index 15f5392..3a88465 100644
--- a/slice_effect.cpp
+++ b/slice_effect.cpp
@@ -1,4 +1,4 @@
-#include <GL/glew.h>
+#include <epoxy/gl.h>
 
 #include "effect_chain.h"
 #include "slice_effect.h"
diff --git a/slice_effect.h b/slice_effect.h
index 17202d7..1c363ea 100644
--- a/slice_effect.h
+++ b/slice_effect.h
@@ -10,7 +10,7 @@
 // Note that vertical slices happen from the bottom, not the top, due to the
 // OpenGL coordinate system.
 
-#include <GL/glew.h>
+#include <epoxy/gl.h>
 #include <string>
 
 #include "effect.h"
diff --git a/slice_effect_test.cpp b/slice_effect_test.cpp
index efa6803..410439a 100644
--- a/slice_effect_test.cpp
+++ b/slice_effect_test.cpp
@@ -1,6 +1,6 @@
 // Unit tests for SliceEffect.
 
-#include <GL/glew.h>
+#include <epoxy/gl.h>
 
 #include "effect_chain.h"
 #include "flat_input.h"
diff --git a/test_util.cpp b/test_util.cpp
index cb97236..ec9cbf9 100644
--- a/test_util.cpp
+++ b/test_util.cpp
@@ -2,11 +2,11 @@
 #include <math.h>
 #include <stdio.h>
 #include <algorithm>
+#include <epoxy/gl.h>
+#include <gtest/gtest.h>
+#include <gtest/gtest-message.h>
 
 #include "flat_input.h"
-#include "glew.h"
-#include "gtest/gtest.h"
-#include "gtest/gtest-message.h"
 #include "init.h"
 #include "resource_pool.h"
 #include "test_util.h"
diff --git a/test_util.h b/test_util.h
index ff568ba..e5e6551 100644
--- a/test_util.h
+++ b/test_util.h
@@ -1,7 +1,7 @@
 #ifndef _MOVIT_TEST_UTIL_H
 #define _MOVIT_TEST_UTIL_H 1
 
-#include <GL/glew.h>
+#include <epoxy/gl.h>
 #include "effect_chain.h"
 #include "image_format.h"
 
diff --git a/unsharp_mask_effect.h b/unsharp_mask_effect.h
index e6d3790..7a2052b 100644
--- a/unsharp_mask_effect.h
+++ b/unsharp_mask_effect.h
@@ -10,7 +10,7 @@
 // See DeconvolutionSharpenEffect for a different, possibly better
 // sharpening algorithm.
 
-#include <GL/glew.h>
+#include <epoxy/gl.h>
 #include <assert.h>
 #include <string>
 
diff --git a/unsharp_mask_effect_test.cpp b/unsharp_mask_effect_test.cpp
index 69ea5f7..e6750ce 100644
--- a/unsharp_mask_effect_test.cpp
+++ b/unsharp_mask_effect_test.cpp
@@ -1,6 +1,6 @@
 // Unit tests for UnsharpMaskEffect.
 
-#include <GL/glew.h>
+#include <epoxy/gl.h>
 #include <math.h>
 
 #include "effect_chain.h"
diff --git a/util.cpp b/util.cpp
index 8162f71..372064b 100644
--- a/util.cpp
+++ b/util.cpp
@@ -1,4 +1,4 @@
-#include <GL/glew.h>
+#include <epoxy/gl.h>
 #include <assert.h>
 #include <math.h>
 #include <stdio.h>
diff --git a/util.h b/util.h
index c59231d..5c15c9f 100644
--- a/util.h
+++ b/util.h
@@ -3,7 +3,7 @@
 
 // Various utilities.
 
-#include <GL/glew.h>
+#include <epoxy/gl.h>
 #include <stdio.h>
 #include <stdlib.h>
 #include <Eigen/Core>
diff --git a/vignette_effect.cpp b/vignette_effect.cpp
index 94383ff..d8b4f9b 100644
--- a/vignette_effect.cpp
+++ b/vignette_effect.cpp
@@ -1,4 +1,4 @@
-#include <GL/glew.h>
+#include <epoxy/gl.h>
 #include <assert.h>
 #include <math.h>
 
diff --git a/vignette_effect.h b/vignette_effect.h
index 737a834..fdf1a11 100644
--- a/vignette_effect.h
+++ b/vignette_effect.h
@@ -4,7 +4,7 @@
 // A circular vignette, falling off as cos² of the distance from the center
 // (the classic formula for approximating a real lens).
 
-#include <GL/glew.h>
+#include <epoxy/gl.h>
 #include <string>
 
 #include "effect.h"
diff --git a/vignette_effect_test.cpp b/vignette_effect_test.cpp
index 9c28852..010fbc4 100644
--- a/vignette_effect_test.cpp
+++ b/vignette_effect_test.cpp
@@ -1,6 +1,6 @@
 // Unit tests for VignetteEffect.
 
-#include <GL/glew.h>
+#include <epoxy/gl.h>
 #include <math.h>
 
 #include "effect_chain.h"
diff --git a/white_balance_effect.cpp b/white_balance_effect.cpp
index 0aa85da..69759ad 100644
--- a/white_balance_effect.cpp
+++ b/white_balance_effect.cpp
@@ -1,6 +1,6 @@
 #include <Eigen/Core>
 #include <Eigen/LU>
-#include <GL/glew.h>
+#include <epoxy/gl.h>
 #include <assert.h>
 
 #include "colorspace_conversion_effect.h"
diff --git a/white_balance_effect.h b/white_balance_effect.h
index 43bfccb..f438b91 100644
--- a/white_balance_effect.h
+++ b/white_balance_effect.h
@@ -3,7 +3,7 @@
 
 // Color correction in LMS color space.
 
-#include <GL/glew.h>
+#include <epoxy/gl.h>
 #include <string>
 
 #include "effect.h"
diff --git a/white_balance_effect_test.cpp b/white_balance_effect_test.cpp
index 5d51dd8..b064207 100644
--- a/white_balance_effect_test.cpp
+++ b/white_balance_effect_test.cpp
@@ -1,6 +1,6 @@
 // Unit tests for WhiteBalanceEffect.
 
-#include <GL/glew.h>
+#include <epoxy/gl.h>
 
 #include "effect_chain.h"
 #include "gtest/gtest.h"
diff --git a/widgets.cpp b/widgets.cpp
index 3bf53c7..8726021 100644
--- a/widgets.cpp
+++ b/widgets.cpp
@@ -1,4 +1,4 @@
-#include <GL/glew.h>
+#include <epoxy/gl.h>
 #include <math.h>
 
 #include "widgets.h"
diff --git a/ycbcr_input.cpp b/ycbcr_input.cpp
index 4974715..dc5e4d9 100644
--- a/ycbcr_input.cpp
+++ b/ycbcr_input.cpp
@@ -1,6 +1,6 @@
 #include <Eigen/Core>
 #include <Eigen/LU>
-#include <GL/glew.h>
+#include <epoxy/gl.h>
 #include <assert.h>
 #include <stdio.h>
 #include <string.h>
diff --git a/ycbcr_input.h b/ycbcr_input.h
index 2466eed..bf6d800 100644
--- a/ycbcr_input.h
+++ b/ycbcr_input.h
@@ -5,7 +5,7 @@
 // imprecisely, called “YUV”), which is typically what you get from a video decoder.
 // It upsamples planes as needed, using the default linear upsampling OpenGL gives you.
 
-#include <GL/glew.h>
+#include <epoxy/gl.h>
 #include <assert.h>
 #include <string>
 
diff --git a/ycbcr_input_test.cpp b/ycbcr_input_test.cpp
index 352fe29..6895b38 100644
--- a/ycbcr_input_test.cpp
+++ b/ycbcr_input_test.cpp
@@ -1,7 +1,7 @@
 // Unit tests for YCbCrInput.
 // FIXME: This class really ought to support mipmaps.
 
-#include <GL/glew.h>
+#include <epoxy/gl.h>
 #include <stddef.h>
 
 #include "effect_chain.h"