Add --disable-png configure option.

4 files changed, 73 insertions, 2 deletions

diff --git a/configure.ac b/configure.ac
index e14f04e..1d6138a 100644
--- a/configure.ac
+++ b/configure.ac
@@ -31,6 +31,14 @@ AC_PROG_LN_S
 AC_PROG_MAKE_SET
 AC_PROG_LIBTOOL
 
+dnl PNG canvas export
+AC_ARG_ENABLE([png],
+              [AS_HELP_STRING([--enable-png],
+                              [Enable PNG canvas export [default=yes]])],
+              [],
+              [enable_png=yes])
+AM_CONDITIONAL([PNG], [test "$enable_png" != "no"])
+
 dnl OpenGL canvas export
 AC_ARG_ENABLE([gl],
               [AS_HELP_STRING([--enable-gl],
diff --git a/libdimension/Makefile.am b/libdimension/Makefile.am
index 4ce01ff..4f427d0 100644
--- a/libdimension/Makefile.am
+++ b/libdimension/Makefile.am
@@ -63,7 +63,6 @@ libdimension_la_SOURCES = $(nobase_include_HEADERS)                            \
                           object.c                                             \
                           perspective.c                                        \
                           phong.c                                              \
-                          png.c                                                \
                           point_light.c                                        \
                           progress.c                                           \
                           raytrace.c                                           \
@@ -73,7 +72,14 @@ libdimension_la_SOURCES = $(nobase_include_HEADERS)                            \
                           sphere.c                                             \
                           texture.c
 libdimension_la_LDFLAGS = -version-info 0:0:0 $(AM_LDFLAGS)
-libdimension_la_LIBADD  = -lm -lpthread -lpng
+libdimension_la_LIBADD  = -lm -lpthread
+
+if PNG
+libdimension_la_SOURCES += png.c
+libdimension_la_LIBADD  += -lpng
+else
+libdimension_la_SOURCES += png-stubs.c
+endif
 
 if GL
 libdimension_la_SOURCES += gl.c
diff --git a/libdimension/png-stubs.c b/libdimension/png-stubs.c
new file mode 100644
index 0000000..eca7697
--- /dev/null
+++ b/libdimension/png-stubs.c
@@ -0,0 +1,53 @@
+/*************************************************************************
+ * Copyright (C) 2010 Tavian Barnes <tavianator@gmail.com>               *
+ *                                                                       *
+ * This file is part of The Dimension Library.                           *
+ *                                                                       *
+ * The Dimension Library is free software; you can redistribute it and/  *
+ * or modify it under the terms of the GNU Lesser General Public License *
+ * as published by the Free Software Foundation; either version 3 of the *
+ * License, or (at your option) any later version.                       *
+ *                                                                       *
+ * The Dimension Library is distributed in the hope that it will be      *
+ * useful, but WITHOUT ANY WARRANTY; without even the implied warranty   *
+ * of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU  *
+ * Lesser General Public License for more details.                       *
+ *                                                                       *
+ * You should have received a copy of the GNU Lesser General Public      *
+ * License along with this program.  If not, see                         *
+ * <http://www.gnu.org/licenses/>.                                       *
+ *************************************************************************/
+
+#include "dimension.h"
+
+/* Stubs for PNG functions when compiled with --disable-png */
+
+int
+dmnsn_png_optimize_canvas(dmnsn_canvas *canvas)
+{
+  return 1;
+}
+
+int
+dmnsn_png_write_canvas(const dmnsn_canvas *canvas, FILE *file)
+{
+  return 1;
+}
+
+dmnsn_progress *
+dmnsn_png_write_canvas_async(const dmnsn_canvas *canvas, FILE *file)
+{
+  return NULL;
+}
+
+dmnsn_canvas *
+dmnsn_png_read_canvas(FILE *file)
+{
+  return NULL;
+}
+
+dmnsn_progress *
+dmnsn_png_read_canvas_async(dmnsn_canvas **canvas, FILE *file)
+{
+  return NULL;
+}
diff --git a/tests/libdimension/Makefile.am b/tests/libdimension/Makefile.am
index 9c6c8ad..6fc3dc7 100644
--- a/tests/libdimension/Makefile.am
+++ b/tests/libdimension/Makefile.am
@@ -29,6 +29,10 @@ check_PROGRAMS    = error-test                                                 \
 TESTS             = $(check_PROGRAMS)
 XFAIL_TESTS       = error-test
 
+if !PNG
+XFAIL_TESTS += png-test
+endif
+
 if !GL
 XFAIL_TESTS += gl-test
 endif