From 36a27c6759d1d7c7d17133beebed207c90c5964a Mon Sep 17 00:00:00 2001
From: Larry Ewing <lewing@gimp.org>
Date: Wed, 17 Nov 1999 23:21:34 +0000
Subject: [PATCH] implement the bounds method correctly.
 (compute_viewport_affine): compute

1999-11-17  Larry Ewing  <lewing@gimp.org>

	* src/gnome-canvas-pixbuf.c (gnome_canvas_pixbuf_bounds):
	implement the bounds method correctly.
	(compute_viewport_affine): compute the affine need to fit the
	image within the viewport given by the args.
	(compute_render_affine): call compute_viewport_affine.
---
 gdk-pixbuf/ChangeLog             |  8 ++++
 gdk-pixbuf/gnome-canvas-pixbuf.c | 64 ++++++++++++++++++++------------
 2 files changed, 48 insertions(+), 24 deletions(-)

diff --git a/gdk-pixbuf/ChangeLog b/gdk-pixbuf/ChangeLog
index 78196f360f..322a1ba4b6 100644
--- a/gdk-pixbuf/ChangeLog
+++ b/gdk-pixbuf/ChangeLog
@@ -1,3 +1,11 @@
+1999-11-17  Larry Ewing  <lewing@gimp.org>
+
+	* src/gnome-canvas-pixbuf.c (gnome_canvas_pixbuf_bounds):
+	implement the bounds method correctly.
+	(compute_viewport_affine): compute the affine need to fit the 
+	image within the viewport given by the args.
+	(compute_render_affine): call compute_viewport_affine.
+
 1999-11-16  Havoc Pennington  <hp@pobox.com>
 
 	* src/gdk-pixbuf-drawable.h: Use includes from the current
diff --git a/gdk-pixbuf/gnome-canvas-pixbuf.c b/gdk-pixbuf/gnome-canvas-pixbuf.c
index 52b445d136..1504e96c4e 100644
--- a/gdk-pixbuf/gnome-canvas-pixbuf.c
+++ b/gdk-pixbuf/gnome-canvas-pixbuf.c
@@ -454,20 +454,19 @@ compute_xform_scaling (double *affine, ArtPoint *i_c, ArtPoint *j_c)
 	j_c->y -= orig_c.y;
 }
 
-/* Computes the affine transformation with which the pixbuf needs to be
- * transformed to render it on the canvas.  This is not the same as the
- * item_to_canvas transformation because we may need to scale the pixbuf by some
- * other amount.
+/* computes the addtional resolution dependent affine needed to
+ * fit the image within its viewport defined by x,y,width and height
+ * args
  */
 static void
-compute_render_affine (GnomeCanvasPixbuf *gcp, double *render_affine, double *i2c)
+compute_viewport_affine (GnomeCanvasPixbuf *gcp, double *viewport_affine, double *i2c)
 {
 	PixbufPrivate *priv;
 	ArtPoint i_c, j_c;
 	double i_len, j_len;
 	double si_len, sj_len;
 	double ti_len, tj_len;
-	double scale[6], translate[6], composite[6];
+	double scale[6], translate[6];
 	double w, h;
 	double x, y;
 
@@ -548,8 +547,21 @@ compute_render_affine (GnomeCanvasPixbuf *gcp, double *render_affine, double *i2
 
 	art_affine_scale (scale, si_len, sj_len);
 	art_affine_translate (translate, ti_len, tj_len);
-	art_affine_multiply (composite, scale, translate);
-	art_affine_multiply (render_affine, composite, i2c);
+	art_affine_multiply (viewport_affine, scale, translate);
+}
+
+/* Computes the affine transformation with which the pixbuf needs to be
+ * transformed to render it on the canvas.  This is not the same as the
+ * item_to_canvas transformation because we may need to scale the pixbuf 
+ * by some other amount.
+ */
+static void
+compute_render_affine (GnomeCanvasPixbuf *gcp, double *render_affine, double *i2c)
+{
+	double viewport_affine[6];
+	
+	compute_viewport_affine (gcp, viewport_affine, i2c);
+	art_affine_multiply (render_affine, viewport_affine, i2c);
 }
 
 /* Recomputes the bounding box of a pixbuf canvas item.  The horizontal and
@@ -809,25 +821,29 @@ gnome_canvas_pixbuf_bounds (GnomeCanvasItem *item, double *x1, double *y1, doubl
 {
 	GnomeCanvasPixbuf *gcp;
 	PixbufPrivate *priv;
+	double i2c[6], viewport_affine[6];
+	ArtDRect rect;
 
 	gcp = GNOME_CANVAS_PIXBUF (item);
 	priv = gcp->priv;
 
-	*x1 = 0.0;
-	*y1 = 0.0;
-
-	if (priv->pixbuf) {
-		if (priv->width_set)
-			*x2 = priv->width;
-		else
-			*x2 = priv->pixbuf->art_pixbuf->width;
-
-		if (priv->height_set)
-			*y2 = priv->height;
-		else
-			*y2 = priv->pixbuf->art_pixbuf->height;
-	} else {
-		*x2 = 0.0;
-		*y2 = 0.0;
+	if (!priv->pixbuf) {
+		*x1 = *y1 = *x2 = *y2 = 0.0;
+		return;
 	}
+
+	rect.x0 = 0.0;
+	rect.x1 = priv->pixbuf->art_pixbuf->width;
+
+	rect.y0 = 0.0;
+	rect.y1 = priv->pixbuf->art_pixbuf->height;
+       
+	gnome_canvas_item_i2c_affine (item, i2c);
+	compute_viewport_affine (gcp, viewport_affine, i2c);
+	art_drect_affine_transform (&rect, &rect, viewport_affine);
+
+	*x1 = rect.x0;
+	*y1 = rect.y0;
+	*x2 = rect.x1;
+	*y2 = rect.y1;
 }