[telegnome] Port from GdkDrawable to Cairo

[Colin Watson <cjwatson src gnome org>]

commit 6bb4fe467e24cb38350e9a92fd78918173df4938
Author: Colin Watson <cjwatson debian org>
Date:   Tue Feb 2 12:53:24 2016 +0000

    Port from GdkDrawable to Cairo
    
    * src/pixpack.c (tg_pixpack_init): Remove priv->scaled_pixbuf.
    (tg_pixpack_destroy): Likewise.
    (tg_pixpack_paint): Likewise.  Use Cairo functions for clipping,
    scaling, and painting.
    * configure.ac (PKG_CHECK_MODULES): Add cairo.

 NEWS          |    1 +
 configure.ac  |    2 +-
 src/pixpack.c |   32 +++++++++++++++-----------------
 3 files changed, 17 insertions(+), 18 deletions(-)
---
diff --git a/NEWS b/NEWS
index e8dc70c..747a8b3 100644
--- a/NEWS
+++ b/NEWS
@@ -7,6 +7,7 @@ Changes in TeleGNOME 0.2.1
  * Port from gtk_timeout_* to GLib equivalents.
  * Port from GtkCList to GtkTreeView and friends.
  * Port to new (as of GTK+ 2.4) GtkToolbar API.
+ * Port from GdkDrawable to Cairo.
 
 Changes in TeleGNOME 0.2.0
 ==========================
diff --git a/configure.ac b/configure.ac
index 8299330..3f8ce1c 100644
--- a/configure.ac
+++ b/configure.ac
@@ -23,7 +23,7 @@ AC_PROG_INSTALL
 AC_DEFINE_UNQUOTED([SYSCONFDIR], "$sysconfdir", [System configuration directory.])
 
 AM_PATH_GLIB_2_0([2.44.0], [], [AC_MSG_ERROR([GLib >= 2.44.0 is required])], [gobject gio])
-PKG_CHECK_MODULES([TELEGNOME], [gtk+-2.0 >= 2.20 gdk-pixbuf-2.0 >= 2.26 dconf uuid])
+PKG_CHECK_MODULES([TELEGNOME], [gtk+-2.0 >= 2.20 gdk-pixbuf-2.0 >= 2.26 cairo dconf uuid])
 
 AC_ARG_VAR([XMLLINT], [the xmllint program])
 AC_PATH_PROG([XMLLINT], [xmllint])
diff --git a/src/pixpack.c b/src/pixpack.c
index f328e40..9e3a9fb 100644
--- a/src/pixpack.c
+++ b/src/pixpack.c
@@ -20,11 +20,13 @@
 ** Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
 **
 */
+
+#include <cairo.h>
+
 #include "pixpack.h"
 
 struct _TgPixPackPrivate {
     GdkPixbuf *pixbuf;
-    GdkPixbuf *scaled_pixbuf;
 
     gboolean is_resize;
     gboolean autosize;
@@ -96,7 +98,6 @@ tg_pixpack_init(TgPixPack *pixpack)
     priv = g_new0(TgPixPackPrivate, 1);
 
     priv->pixbuf = NULL;
-    priv->scaled_pixbuf = NULL;
     priv->is_resize = FALSE;
     priv->autosize = FALSE;
     pixpack->private_data = priv;
@@ -129,8 +130,6 @@ tg_pixpack_destroy(GtkObject *object)
     if (private) {
        if (private->pixbuf)
            g_clear_object(&private->pixbuf);
-       if (private->scaled_pixbuf)
-           g_clear_object(&private->scaled_pixbuf);
 
        g_clear_pointer(&pixpack->private_data, g_free);
     }
@@ -206,6 +205,7 @@ tg_pixpack_paint(TgPixPack* pixpack, GdkRectangle *area)
     GtkWidget *widget;
     TgPixPackPrivate *private;
     GdkWindow *window;
+    cairo_t *cr;
 
     g_return_if_fail(pixpack != NULL);
     g_return_if_fail(TG_IS_PIXPACK(pixpack));
@@ -214,8 +214,8 @@ tg_pixpack_paint(TgPixPack* pixpack, GdkRectangle *area)
     private = pixpack->private_data;
 
     if (!private->is_resize) {
-       area->height = gdk_pixbuf_get_height(private->scaled_pixbuf);
-       area->width = gdk_pixbuf_get_width(private->scaled_pixbuf);
+       area->height = gdk_pixbuf_get_height(private->pixbuf);
+       area->width = gdk_pixbuf_get_width(private->pixbuf);
        area->x = 0;
        area->y = 0;
     }
@@ -226,21 +226,19 @@ tg_pixpack_paint(TgPixPack* pixpack, GdkRectangle *area)
 
     window = gtk_widget_get_window(widget);
     gdk_window_clear_area(window, area->x, area->y, area->width, area->height);
-    gdk_gc_set_clip_rectangle(gtk_widget_get_style(widget)->black_gc, area);
 
     if (NULL == private->pixbuf)
        return;
 
-    if (private->scaled_pixbuf)
-       g_object_unref(private->scaled_pixbuf);
-
-    private->scaled_pixbuf = gdk_pixbuf_scale_simple(private->pixbuf,
-                                                    area->width, area->height,
-                                                    GDK_INTERP_BILINEAR);
-    gdk_pixbuf_render_to_drawable(private->scaled_pixbuf, window,
-                                 gtk_widget_get_style(widget)->black_gc, 0, 0,
-                                 area->x, area->y, area->width, area->height,
-                                 GDK_RGB_DITHER_MAX, 1, 1);
+    cr = gdk_cairo_create(GDK_DRAWABLE(window));
+    gdk_cairo_set_source_pixbuf(cr, private->pixbuf, 0, 0);
+    cairo_rectangle(cr, area->x, area->y, area->width, area->height);
+    cairo_clip(cr);
+    cairo_scale(cr,
+               area->width / gdk_pixbuf_get_width(private->pixbuf),
+               area->height / gdk_pixbuf_get_height(private->pixbuf));
+    cairo_paint(cr);
+    cairo_destroy(cr);
 
     private->is_resize = FALSE;
 }