libgimp*: make more libgimp* libraries introspected.

Only libgimpwidgets is not introspected yet as it didn't work from
scratch and I don't have the time right now to look into it. Anyway with
all the others, we already have so many warnings during the GObject
Introspection step now that we have a lot of work to do already!

libgimpmath/Makefile.am

@@ -58,19 +58,14 @@ EXTRA_DIST = \
 
 lib_LTLIBRARIES = libgimpmath-@GIMP_API_VERSION@.la
 
+AUTOMAKE_OPTIONS = subdir-objects
+include $(top_srcdir)/libgimpmath/Makefile.gi
+
 libgimpmath_@GIMP_API_VERSION@_la_SOURCES = \
-	gimpmath.h	\
-	gimpmathtypes.h	\
-	gimpmatrix.c	\
-	gimpmatrix.h	\
-	gimpvector.c	\
-	gimpvector.h
+	$(libgimpmath_introspectable)
 
 libgimpmathinclude_HEADERS = \
-	gimpmath.h	\
-	gimpmathtypes.h	\
-	gimpmatrix.h	\
-	gimpvector.h
+	$(libgimpmath_introspectable_headers)
 
 libgimpmath_@GIMP_API_VERSION@_la_LDFLAGS = \
 	-version-info $(LT_VERSION_INFO)	\

libgimpmath/Makefile.gi

@@ -0,0 +1,12 @@
+# Introspectable sources for libgimpmath
+#
+libgimpmath_introspectable_headers = \
+	$(top_srcdir)/libgimpmath/gimpmath.h		\
+	$(top_srcdir)/libgimpmath/gimpmathtypes.h	\
+	$(top_srcdir)/libgimpmath/gimpmatrix.h		\
+	$(top_srcdir)/libgimpmath/gimpvector.h
+
+libgimpmath_introspectable = \
+	$(top_srcdir)/libgimpmath/gimpmatrix.c		\
+	$(top_srcdir)/libgimpmath/gimpvector.c		\
+	$(libgimpmath_introspectable_headers)