label: Draw all text using PangoCairo

This includes the addition of a "small" helper function,
_gtk_pango_fill_layout() that ignores color information. This
functionality is not available inside Pango and until that happens, we
need this fix. The bug is filed at:

https://bugzilla.gnome.org/show_bug.cgi?id=624917

1 files changed, 233 insertions, 0 deletions

diff --git a/gtk/gtkpango.c b/gtk/gtkpango.c
new file mode 100644
index 0000000000..be6eb4e57e
--- /dev/null
+++ b/gtk/gtkpango.c
@@ -0,0 +1,233 @@
+/* gtktextdisplay.c - display layed-out text
+ *
+ * Copyright (c) 2010 Red Hat, Inc.
+ *
+ * This 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 2 of the License, or (at your option) any later version.
+ *
+ * This 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 library; if not, write to the Free
+ * Software Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
+ */
+/*
+ * Modified by the GTK+ Team and others 1997-2000.  See the AUTHORS
+ * file for a list of people on the GTK+ Team.  See the ChangeLog
+ * files for a list of changes.  These files are distributed with
+ * GTK+ at ftp://ftp.gtk.org/pub/gtk/.
+ */
+
+#include "config.h"
+#include <pango/pangocairo.h>
+#include "gtkintl.h"
+
+#define GTK_TYPE_FILL_LAYOUT_RENDERER            (_gtk_fill_layout_renderer_get_type())
+#define GTK_FILL_LAYOUT_RENDERER(object)         (G_TYPE_CHECK_INSTANCE_CAST ((object), GTK_TYPE_FILL_LAYOUT_RENDERER, GtkFillLayoutRenderer))
+#define GTK_IS_FILL_LAYOUT_RENDERER(object)      (G_TYPE_CHECK_INSTANCE_TYPE ((object), GTK_TYPE_FILL_LAYOUT_RENDERER))
+#define GTK_FILL_LAYOUT_RENDERER_CLASS(klass)    (G_TYPE_CHECK_CLASS_CAST ((klass), GTK_TYPE_FILL_LAYOUT_RENDERER, GtkFillLayoutRendererClass))
+#define GTK_IS_FILL_LAYOUT_RENDERER_CLASS(klass) (G_TYPE_CHECK_CLASS_TYPE ((klass), GTK_TYPE_FILL_LAYOUT_RENDERER))
+#define GTK_FILL_LAYOUT_RENDERER_GET_CLASS(obj)  (G_TYPE_INSTANCE_GET_CLASS ((obj), GTK_TYPE_FILL_LAYOUT_RENDERER, GtkFillLayoutRendererClass))
+
+typedef struct _GtkFillLayoutRenderer      GtkFillLayoutRenderer;
+typedef struct _GtkFillLayoutRendererClass GtkFillLayoutRendererClass;
+
+struct _GtkFillLayoutRenderer
+{
+  PangoRenderer parent_instance;
+
+  cairo_t *cr;
+};
+
+struct _GtkFillLayoutRendererClass
+{
+  PangoRendererClass parent_class;
+};
+
+G_DEFINE_TYPE (GtkFillLayoutRenderer, _gtk_fill_layout_renderer, PANGO_TYPE_RENDERER)
+
+static void
+gtk_fill_layout_renderer_draw_glyphs (PangoRenderer     *renderer,
+                                      PangoFont         *font,
+                                      PangoGlyphString  *glyphs,
+                                      int                x,
+                                      int                y)
+{
+  GtkFillLayoutRenderer *text_renderer = GTK_FILL_LAYOUT_RENDERER (renderer);
+
+  cairo_move_to (text_renderer->cr, (double)x / PANGO_SCALE, (double)y / PANGO_SCALE);
+  pango_cairo_show_glyph_string (text_renderer->cr, font, glyphs);
+}
+
+static void
+gtk_fill_layout_renderer_draw_glyph_item (PangoRenderer     *renderer,
+                                          const char        *text,
+                                          PangoGlyphItem    *glyph_item,
+                                          int                x,
+                                          int                y)
+{
+  GtkFillLayoutRenderer *text_renderer = GTK_FILL_LAYOUT_RENDERER (renderer);
+
+  cairo_move_to (text_renderer->cr, (double)x / PANGO_SCALE, (double)y / PANGO_SCALE);
+  pango_cairo_show_glyph_item (text_renderer->cr, text, glyph_item);
+}
+
+static void
+gtk_fill_layout_renderer_draw_rectangle (PangoRenderer     *renderer,
+                                         PangoRenderPart    part,
+                                         int                x,
+                                         int                y,
+                                         int                width,
+                                         int                height)
+{
+  GtkFillLayoutRenderer *text_renderer = GTK_FILL_LAYOUT_RENDERER (renderer);
+
+  if (part == PANGO_RENDER_PART_BACKGROUND)
+    return;
+
+  cairo_rectangle (text_renderer->cr,
+                   (double)x / PANGO_SCALE, (double)y / PANGO_SCALE,
+		   (double)width / PANGO_SCALE, (double)height / PANGO_SCALE);
+  cairo_fill (text_renderer->cr);
+}
+
+static void
+gtk_fill_layout_renderer_draw_trapezoid (PangoRenderer     *renderer,
+                                         PangoRenderPart    part,
+                                         double             y1_,
+                                         double             x11,
+                                         double             x21,
+                                         double             y2,
+                                         double             x12,
+                                         double             x22)
+{
+  GtkFillLayoutRenderer *text_renderer = GTK_FILL_LAYOUT_RENDERER (renderer);
+  cairo_matrix_t matrix;
+  cairo_t *cr;
+
+  cr = text_renderer->cr;
+
+  cairo_save (cr);
+
+  /* use identity scale, but keep translation */
+  cairo_get_matrix (cr, &matrix);
+  matrix.xx = matrix.yy = 1;
+  matrix.xy = matrix.yx = 0;
+  cairo_set_matrix (cr, &matrix);
+
+  cairo_move_to (cr, x11, y1_);
+  cairo_line_to (cr, x21, y1_);
+  cairo_line_to (cr, x22, y2);
+  cairo_line_to (cr, x12, y2);
+  cairo_close_path (cr);
+
+  cairo_fill (cr);
+
+  cairo_restore (cr);
+}
+
+static void
+gtk_fill_layout_renderer_draw_error_underline (PangoRenderer *renderer,
+                                               int            x,
+                                               int            y,
+                                               int            width,
+                                               int            height)
+{
+  GtkFillLayoutRenderer *text_renderer = GTK_FILL_LAYOUT_RENDERER (renderer);
+
+  pango_cairo_show_error_underline (text_renderer->cr,
+                                    (double)x / PANGO_SCALE, (double)y / PANGO_SCALE,
+                                    (double)width / PANGO_SCALE, (double)height / PANGO_SCALE);
+}
+
+static void
+gtk_fill_layout_renderer_draw_shape (PangoRenderer   *renderer,
+                                     PangoAttrShape  *attr,
+                                     int              x,
+                                     int              y)
+{
+  GtkFillLayoutRenderer *text_renderer = GTK_FILL_LAYOUT_RENDERER (renderer);
+  cairo_t *cr = text_renderer->cr;
+  PangoLayout *layout;
+  PangoCairoShapeRendererFunc shape_renderer;
+  gpointer                    shape_renderer_data;
+
+  layout = pango_renderer_get_layout (renderer);
+
+  if (!layout)
+  	return;
+
+  shape_renderer = pango_cairo_context_get_shape_renderer (pango_layout_get_context (layout),
+							   &shape_renderer_data);
+
+  if (!shape_renderer)
+    return;
+
+  cairo_save (cr);
+
+  cairo_move_to (cr, (double)x / PANGO_SCALE, (double)y / PANGO_SCALE);
+
+  shape_renderer (cr, attr, FALSE, shape_renderer_data);
+
+  cairo_restore (cr);
+}
+
+static void
+gtk_fill_layout_renderer_finalize (GObject *object)
+{
+  G_OBJECT_CLASS (_gtk_fill_layout_renderer_parent_class)->finalize (object);
+}
+
+static void
+_gtk_fill_layout_renderer_init (GtkFillLayoutRenderer *renderer)
+{
+}
+
+static void
+_gtk_fill_layout_renderer_class_init (GtkFillLayoutRendererClass *klass)
+{
+  GObjectClass *object_class = G_OBJECT_CLASS (klass);
+  
+  PangoRendererClass *renderer_class = PANGO_RENDERER_CLASS (klass);
+  
+  renderer_class->draw_glyphs = gtk_fill_layout_renderer_draw_glyphs;
+  renderer_class->draw_glyph_item = gtk_fill_layout_renderer_draw_glyph_item;
+  renderer_class->draw_rectangle = gtk_fill_layout_renderer_draw_rectangle;
+  renderer_class->draw_trapezoid = gtk_fill_layout_renderer_draw_trapezoid;
+  renderer_class->draw_error_underline = gtk_fill_layout_renderer_draw_error_underline;
+  renderer_class->draw_shape = gtk_fill_layout_renderer_draw_shape;
+
+  object_class->finalize = gtk_fill_layout_renderer_finalize;
+}
+
+void
+_gtk_pango_fill_layout (cairo_t     *cr,
+                        PangoLayout *layout)
+{
+  static GtkFillLayoutRenderer *renderer = NULL;
+  gboolean has_current_point;
+  double current_x, current_y;
+
+  has_current_point = cairo_has_current_point (cr);
+  cairo_get_current_point (cr, &current_x, &current_y);
+
+  if (renderer == NULL)
+    renderer = g_object_new (GTK_TYPE_FILL_LAYOUT_RENDERER, NULL);
+
+  cairo_save (cr);
+  cairo_translate (cr, current_x, current_y);
+
+  renderer->cr = cr;
+  pango_renderer_draw_layout (PANGO_RENDERER (renderer), layout, 0, 0);
+
+  cairo_restore (cr);
+
+  if (has_current_point)
+    cairo_move_to (cr, current_x, current_y);
+}
+