[gegl] Meson: Various fixes and simplifications

[Øyvind "pippin" Kolås <ok src gnome org>]

commit be8978bab03e8cb1dd48b884398099c560bad48b
Author: Xavier Claessens <xavier claessens collabora com>
Date:   Sun Apr 24 20:12:12 2022 -0400

    Meson: Various fixes and simplifications
    
    This fix usage of gegl as subproject.

 gegl/meson.build           |  1 +
 meson.build                | 54 +++++++++++++++++++++++++++-------------------
 seamless-clone/meson.build | 31 +++++++++++---------------
 3 files changed, 45 insertions(+), 41 deletions(-)
---
diff --git a/gegl/meson.build b/gegl/meson.build
index 54977f5ed..834c9c50c 100644
--- a/gegl/meson.build
+++ b/gegl/meson.build
@@ -137,6 +137,7 @@ if g_ir.found()
     symbol_prefix: 'gegl',
     header: 'gegl.h',
     includes: [ 'GLib-2.0', 'GObject-2.0', 'Babl-0.1' ],
+    dependencies: [babl],
     export_packages: 'gegl-' + api_version,
     install: true,
   )
diff --git a/meson.build b/meson.build
index 7af9178ec..f55a45e83 100644
--- a/meson.build
+++ b/meson.build
@@ -493,6 +493,38 @@ subdir('libs/rgbe')
 subdir('opencl')
 subdir('gegl')
 subdir('libs/npd')
+
+# pkg-config file
+gegl_pub_deps = [
+  glib,
+  gobject,
+  gmodule,
+  gio,
+  json_glib,
+  babl,
+]
+
+pkgconfig.generate(gegl_lib,
+  filebase: 'gegl-' + api_version,
+  name: 'GEGL',
+  description: 'Generic Graphics Library',
+  version: meson.project_version(),
+  variables: 'pluginsdir=' + '${prefix}' / get_option('libdir') / api_name,
+  libraries: gegl_pub_deps,
+  libraries_private: gegl_npd_lib,
+  subdirs: api_name,
+)
+
+gegl_dep = declare_dependency(link_with: gegl_lib,
+  include_directories: geglInclude,
+  dependencies: [gegl_pub_deps, libnpd],
+  sources: g_ir.found() ? gegl_gir : [],
+)
+
+if meson.version().version_compare('>=0.54.0')
+  meson.override_dependency('gegl-' + api_version, gegl_dep)
+endif
+
 subdir('seamless-clone')
 subdir('bin')
 subdir('tools')
@@ -538,28 +570,6 @@ if w3m.found()
   endif
 endif
 
-# pkg-config file
-pkgconfig.generate(filebase: 'gegl-' + api_version,
-  name: 'GEGL',
-  description: 'Generic Graphics Library',
-  version: meson.project_version(),
-  variables: 'pluginsdir=' + '${prefix}' / get_option('libdir') / api_name,
-  requires: [
-    gobject,
-    gmodule,
-    gio,
-    json_glib,
-    babl,
-  ],
-  libraries: [
-    gegl_lib,
-    gegl_npd_lib,
-    math,
-  ],
-  subdirs: api_name,
-)
-
-
 ################################################################################
 # Build summary
 
diff --git a/seamless-clone/meson.build b/seamless-clone/meson.build
index d67e279a9..55d86453d 100644
--- a/seamless-clone/meson.build
+++ b/seamless-clone/meson.build
@@ -18,14 +18,9 @@ seamlessclone_lib = library('gegl-sc-' + api_version,
   seamlessclone_sources,
   include_directories: [ rootInclude, geglInclude, ],
   dependencies: [
-    babl,
-    glib,
-    gobject,
+    gegl_dep,
     poly2tri_c,
   ],
-  link_with: [
-    gegl_lib,
-  ],
   install: true,
 )
 
@@ -34,22 +29,20 @@ install_headers(
   subdir: api_name / 'sc'
 )
 
-
-pkgconfig.generate(
+pkgconfig.generate(seamlessclone_lib,
   filebase: 'gegl-sc-' + api_version,
   name: 'GEGL Seamless Cloning',
   description: 'Seamless Cloning Library Based on GEGL',
   version: meson.project_version(),
-  requires: [
-    gobject,
-    gmodule,
-    gio,
-    json_glib,
-
-    babl,
-    poly2tri_c.type_name() == 'internal' ? [] : poly2tri_c,
-    'gegl-' + api_version,
-  ],
-  libraries: seamlessclone_lib,
+  libraries: gegl_dep,
   subdirs: api_name / 'sc',
 )
+
+gegl_sc_dep = declare_dependency(link_with: seamlessclone_lib,
+  include_directories: seamlessInclude,
+  dependencies: [gegl_dep],
+)
+
+if meson.version().version_compare('>=0.54.0')
+  meson.override_dependency('gegl-sc-' + api_version, gegl_sc_dep)
+endif