New function to draw text into a pixbuf given a rect and a string.

	* libnautilus-extensions/nautilus-gdk-pixbuf-extensions.c:
	(nautilus_gdk_pixbuf_scale_to_fit),
	(nautilus_gdk_pixbuf_draw_text):
	* libnautilus-extensions/nautilus-gdk-pixbuf-extensions.h:
	New function to draw text into a pixbuf given a rect and a
	string.   Factored from the icon factoyr.
	* libnautilus-extensions/nautilus-graphic.c:
	(nautilus_graphic_size_allocate):
	Add support for drawing text.

	* libnautilus-extensions/nautilus-icon-factory.c: (embed_text):
	Factored out gdk pixbuf text drawing.  Use the new text drawing
	function.

	* test/test-nautilus-graphic.c: (create_color_scale):
	Update for text support.

1 files changed, 134 insertions, 1 deletions

diff --git a/libnautilus-private/nautilus-gdk-pixbuf-extensions.c b/libnautilus-private/nautilus-gdk-pixbuf-extensions.c
index e01e861ea..6195245e8 100644
--- a/libnautilus-private/nautilus-gdk-pixbuf-extensions.c
+++ b/libnautilus-private/nautilus-gdk-pixbuf-extensions.c
@@ -25,11 +25,13 @@
 #include <config.h>
 #include <math.h>
 #include "nautilus-gdk-pixbuf-extensions.h"
+#include "nautilus-gdk-extensions.h"
 #include "nautilus-glib-extensions.h"
+#include "nautilus-string.h"
 
 #include <gdk-pixbuf/gdk-pixbuf-loader.h>
-#include <libgnomevfs/gnome-vfs-ops.h>
 #include <libgnomevfs/gnome-vfs-async-ops.h>
+#include <libgnomevfs/gnome-vfs-ops.h>
 
 #define LOAD_BUFFER_SIZE 4096
 
@@ -391,3 +393,134 @@ nautilus_gdk_pixbuf_scale_to_fit (GdkPixbuf *pixbuf, int max_width, int max_heig
 	
 	return pixbuf;
 }
+
+/**
+ * nautilus_gdk_pixbuf_draw_text
+ * @pixbuf: A GdkPixbuf.
+ * @font: A GdkFont.
+ * @destination_rect: An ArtIRect - the destination bounding box for the text.
+ * @text: A string - the text to draw.
+ * @overall_alpha: The overall alpha to use when compositing the text on the pixbuf
+ *
+ * Draw text onto a GdkPixbuf using the given font and rect
+ **/
+void
+nautilus_gdk_pixbuf_draw_text (GdkPixbuf	*pixbuf,
+			       const GdkFont	*font,
+			       const ArtIRect	*destination_rect,
+			       const char	*text,
+			       guint		overall_alpha)
+{
+	ArtIRect	pixbuf_rect;
+	ArtIRect	text_rect;
+	int		width, height;
+	GdkVisual	*visual;
+	GdkPixmap	*pixmap;
+	GdkGC		*gc;
+	GdkColormap	*colormap;
+	int		y;
+	const char	*line;
+	const char	*end_of_line;
+	int		line_length;
+	GdkPixbuf	*text_pixbuf;
+	GdkPixbuf	*text_pixbuf_with_alpha;
+	guchar		*pixels;
+
+	g_return_if_fail (pixbuf != NULL);
+	g_return_if_fail (font != NULL);
+	g_return_if_fail (destination_rect != NULL);
+	g_return_if_fail (text != NULL);
+	g_return_if_fail (nautilus_strlen (text) > 0);
+	g_return_if_fail (overall_alpha <= 255);
+
+	/* Compute the intersection of the text rectangle with the pixbuf.
+	 * This is only to prevent pathological cases from upsetting the
+	 * GdkPixbuf routines. It should not happen in any normal circumstance.
+	 */
+	pixbuf_rect.x0 = 0;
+	pixbuf_rect.y0 = 0;
+	pixbuf_rect.x1 = gdk_pixbuf_get_width (pixbuf);
+	pixbuf_rect.y1 = gdk_pixbuf_get_height (pixbuf);
+	art_irect_intersect (&text_rect, destination_rect, &pixbuf_rect);
+
+	/* Get the system visual. I wish I could do this all in 1-bit mode,
+	 * but I can't.
+	 */
+	visual = gdk_visual_get_system ();
+
+	/* Allocate a GdkPixmap of the appropriate size. */
+	width = text_rect.x1 - text_rect.x0;
+	height = text_rect.y1 - text_rect.y0;
+	pixmap = gdk_pixmap_new (NULL, width, height, visual->depth);
+	gc = gdk_gc_new (pixmap);
+
+	/* Set up a white background. */
+	gdk_rgb_gc_set_foreground (gc, NAUTILUS_RGB_COLOR_WHITE);
+	gdk_draw_rectangle (pixmap, gc, TRUE, 0, 0, width, height);
+	
+	/* Draw black text. */
+	gdk_rgb_gc_set_foreground (gc, NAUTILUS_RGB_COLOR_BLACK);
+	gdk_gc_set_font (gc, (GdkFont *) font);
+	line = text;
+
+	/* FIXME bugzilla.eazel.com xxxx:
+	 * The iteration code should work with strings that dont have 
+	 * new lines.  Its broken right now for single line strings.  The 
+	 * (y + font->ascent) <= height test always fails and no text is drawn.
+	 */
+	if (strchr (line, '\n')) {
+		for (y = font->ascent;
+		     y + font->descent <= height;
+		     y += font->ascent + font->descent) {
+			
+			/* Extract the next line of text. */
+			end_of_line = strchr (line, '\n');
+			line_length = end_of_line == NULL
+				? strlen (line)
+				: end_of_line - line;
+			
+			/* Draw the next line of text. */
+			gdk_draw_text (pixmap, (GdkFont *) font, gc, 0, y,
+				       line, line_length);
+			
+			/* Move on to the subsequent line. */
+			line = end_of_line == NULL
+				? ""
+				: end_of_line + 1;
+		}
+	}
+	else {
+		/* Draw the next line of text. */
+		gdk_draw_text (pixmap, (GdkFont *) font, gc, 0, font->ascent,
+			       line, strlen (line));
+	}
+	gdk_gc_unref (gc);
+
+	/* Convert into a GdkPixbuf with gdk_pixbuf_get_from_drawable. */
+	colormap = gdk_colormap_new (visual, FALSE);
+	text_pixbuf = gdk_pixbuf_get_from_drawable (NULL, pixmap, colormap,
+						    0, 0,
+						    0, 0, width, height);
+	gdk_colormap_unref (colormap);
+	gdk_pixmap_unref (pixmap);
+
+	/* White is not always FF FF FF. So we get the top left corner pixel. */
+	pixels = gdk_pixbuf_get_pixels (text_pixbuf);
+	text_pixbuf_with_alpha = gdk_pixbuf_add_alpha 
+		(text_pixbuf,
+		 TRUE, pixels[0], pixels[1], pixels[2]);
+	gdk_pixbuf_unref (text_pixbuf);
+
+	gdk_pixbuf_composite (text_pixbuf_with_alpha,
+			      pixbuf,
+			      text_rect.x0,
+			      text_rect.y0,
+			      width, height,
+			      text_rect.x0,
+			      text_rect.y0,
+			      1, 1,
+			      GDK_INTERP_BILINEAR,
+			      overall_alpha);
+
+	gdk_pixbuf_unref (text_pixbuf_with_alpha);
+}