From 3e26164dc9ee7cbf7dfbc040e89115a1cd030cf2 Mon Sep 17 00:00:00 2001
From: Sam Hocevar <sam@hocevar.net>
Date: Wed, 9 Aug 2017 20:17:03 +0200
Subject: [PATCH] Add --enable-png configure flag.

---
 build/autotools/m4/lol-conf.m4 | 8 +++++---
 configure.ac                   | 2 ++
 2 files changed, 7 insertions(+), 3 deletions(-)

diff --git a/build/autotools/m4/lol-conf.m4 b/build/autotools/m4/lol-conf.m4
index b3ab4a56..656201f2 100644
--- a/build/autotools/m4/lol-conf.m4
+++ b/build/autotools/m4/lol-conf.m4
@@ -128,9 +128,11 @@ AM_CONDITIONAL(LOL_USE_EGL, test "${ac_cv_my_have_egl}" != "no")
 
 dnl Use libpng? (replacement for SDL_image)
 ac_cv_my_have_libpng="no"
-PKG_CHECK_MODULES(LIBPNG, libpng, [ac_cv_my_have_libpng="yes"], [:])
-if test "${ac_cv_my_have_libpng}" != "no"; then
-  AC_DEFINE(LOL_USE_LIBPNG, 1, Define to 1 to use libpng)
+if test "${enable_png}" != "no"; then
+  PKG_CHECK_MODULES(LIBPNG, libpng, [ac_cv_my_have_libpng="yes"], [:])
+  if test "${ac_cv_my_have_libpng}" != "no"; then
+    AC_DEFINE(LOL_USE_LIBPNG, 1, Define to 1 to use libpng)
+  fi
 fi
 AM_CONDITIONAL(LOL_USE_LIBPNG, test "${ac_cv_my_have_libpng}" != "no")
 
diff --git a/configure.ac b/configure.ac
index 08c333be..8f3de581 100644
--- a/configure.ac
+++ b/configure.ac
@@ -88,6 +88,8 @@ AC_ARG_ENABLE(sdl,
   [  --enable-sdl            build using SDL (default autodetected)])
 AC_ARG_ENABLE(imlib2,
   [  --enable-imlib2         build using Imlib2 (default autodetected)])
+AC_ARG_ENABLE(png,
+  [  --enable-png            build using libpng (default autodetected)])
 
 AC_ARG_ENABLE(test,
   [  --enable-test           build test suite (default yes)])