[gtk/text-to-path: 1/2] gsk: Add gsk_path_builder_add_layout

[Matthias Clasen <matthiasc src gnome org>]

commit ae2bad38b344f763e813b1209fa25af745ed0709
Author: Matthias Clasen <mclasen redhat com>
Date:   Sun Dec 27 00:59:02 2020 -0500

    gsk: Add gsk_path_builder_add_layout
    
    This api makes it easy to turn text into a path that
    can be further manipulated. The implementation currently
    goes via cairo.

 gsk/gskpathbuilder.c | 33 +++++++++++++++++++++++++++++++++
 gsk/gskpathbuilder.h |  4 ++++
 2 files changed, 37 insertions(+)
---
diff --git a/gsk/gskpathbuilder.c b/gsk/gskpathbuilder.c
index 3b578627a0..b8c1e50c96 100644
--- a/gsk/gskpathbuilder.c
+++ b/gsk/gskpathbuilder.c
@@ -941,3 +941,36 @@ gsk_path_builder_svg_arc_to (GskPathBuilder *builder,
                    t);
     }
 }
+
+/**
+ * gsk_path_builder_add_layout:
+ * @builder: a #GskPathBuilder
+ * @layout: the pango layout to add
+ *
+ * Adds the outlines for the glyphs in @layout to
+ * @builder.
+ */
+void
+gsk_path_builder_add_layout (GskPathBuilder *builder,
+                             PangoLayout    *layout)
+{
+  cairo_surface_t *surface;
+  cairo_t *cr;
+  cairo_path_t *cairo_path;
+  GskPath *path;
+
+  surface = cairo_recording_surface_create (CAIRO_CONTENT_COLOR_ALPHA, NULL);
+  cr = cairo_create (surface);
+
+  pango_cairo_layout_path (cr, layout);
+  cairo_path = cairo_copy_path_flat (cr);
+  path = gsk_path_new_from_cairo (cairo_path);
+
+  gsk_path_builder_add_path (builder, path);
+
+  gsk_path_unref (path);
+
+  cairo_path_destroy (cairo_path);
+  cairo_destroy (cr);
+  cairo_surface_destroy (surface);
+}
diff --git a/gsk/gskpathbuilder.h b/gsk/gskpathbuilder.h
index 0a4024b60e..f5c9c81c05 100644
--- a/gsk/gskpathbuilder.h
+++ b/gsk/gskpathbuilder.h
@@ -123,6 +123,10 @@ void                    gsk_path_builder_rel_conic_to           (GskPathBuilder
 GDK_AVAILABLE_IN_ALL
 void                    gsk_path_builder_close                  (GskPathBuilder         *builder);
 
+GDK_AVAILABLE_IN_ALL
+void                    gsk_path_builder_add_layout             (GskPathBuilder         *builder,
+                                                                 PangoLayout            *layout);
+
 G_END_DECLS
 
 #endif /* __GSK_PATH_BUILDER_H__ */