/* GNOME libraries - GdkPixbuf item for the GNOME canvas
*
* Copyright (C) 1999 The Free Software Foundation
*
* Author: Federico Mena-Quintero <federico@gimp.org>
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Library 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
* Library General Public License for more details.
*
* You should have received a copy of the GNU Library General Public
* License along with this library; if not, write to the
* Free Software Foundation, Inc., 59 Temple Place - Suite 330,
* Boston, MA 02111-1307, USA.
*/
#include <config.h>
#include <math.h>
#include <libgnomecanvas/gnome-canvas.h>
#include <libgnomecanvas/gnome-canvas-util.h>
#include <gdk-pixbuf/gdk-pixbuf.h>
#include <libart_lgpl/art_rgb_affine.h>
#include <libart_lgpl/art_rgb_rgba_affine.h>
#include "gnome-canvas-pixbuf.h"
/* Private part of the GnomeCanvasPixbuf structure */
struct _GnomeCanvasPixbufPrivate {
/* Our gdk-pixbuf */
GdkPixbuf *pixbuf;
/* Width value */
gdouble width;
/* Height value */
gdouble height;
/* X translation */
gdouble x;
/* Y translation */
gdouble y;
/* Whether dimensions are set and whether they are in pixels or units */
guint width_set : 1;
guint width_in_pixels : 1;
guint height_set : 1;
guint height_in_pixels : 1;
guint x_in_pixels : 1;
guint y_in_pixels : 1;
};
/* Object argument IDs */
enum {
PROP_0,
PROP_PIXBUF,
PROP_WIDTH,
PROP_WIDTH_SET,
PROP_WIDTH_IN_PIXELS,
PROP_HEIGHT,
PROP_HEIGHT_SET,
PROP_HEIGHT_IN_PIXELS,
PROP_X,
PROP_X_IN_PIXELS,
PROP_Y,
PROP_Y_IN_PIXELS
};
static void gnome_canvas_pixbuf_destroy (GnomeCanvasItem *object);
static void gnome_canvas_pixbuf_set_property (GObject *object,
guint param_id,
const GValue *value,
GParamSpec *pspec);
static void gnome_canvas_pixbuf_get_property (GObject *object,
guint param_id,
GValue *value,
GParamSpec *pspec);
static void gnome_canvas_pixbuf_update (GnomeCanvasItem *item, gdouble *affine,
ArtSVP *clip_path, gint flags);
static void gnome_canvas_pixbuf_draw (GnomeCanvasItem *item, GdkDrawable *drawable,
gint x, gint y, gint width, gint height);
static GnomeCanvasItem *gnome_canvas_pixbuf_point (GnomeCanvasItem *item,
gdouble x,
gdouble y,
gint cx,
gint cy);
static void gnome_canvas_pixbuf_bounds (GnomeCanvasItem *item,
gdouble *x1, gdouble *y1, gdouble *x2, gdouble *y2);
G_DEFINE_TYPE (GnomeCanvasPixbuf, gnome_canvas_pixbuf, GNOME_TYPE_CANVAS_ITEM)
/* Class initialization function for the pixbuf canvas item */
static void
gnome_canvas_pixbuf_class_init (GnomeCanvasPixbufClass *class)
{
GObjectClass *gobject_class;
GnomeCanvasItemClass *item_class;
gobject_class = (GObjectClass *) class;
item_class = (GnomeCanvasItemClass *) class;
gobject_class->set_property = gnome_canvas_pixbuf_set_property;
gobject_class->get_property = gnome_canvas_pixbuf_get_property;
g_object_class_install_property
(gobject_class,
PROP_PIXBUF,
g_param_spec_object ("pixbuf", NULL, NULL,
GDK_TYPE_PIXBUF,
(G_PARAM_READABLE | G_PARAM_WRITABLE)));
g_object_class_install_property
(gobject_class,
PROP_WIDTH,
g_param_spec_double ("width", NULL, NULL,
-G_MAXDOUBLE, G_MAXDOUBLE, 0,
(G_PARAM_READABLE | G_PARAM_WRITABLE)));
g_object_class_install_property
(gobject_class,
PROP_WIDTH_SET,
g_param_spec_boolean ("width_set", NULL, NULL,
FALSE,
(G_PARAM_READABLE | G_PARAM_WRITABLE)));
g_object_class_install_property
(gobject_class,
PROP_WIDTH_IN_PIXELS,
g_param_spec_boolean ("width_in_pixels", NULL, NULL,
FALSE,
(G_PARAM_READABLE | G_PARAM_WRITABLE)));
g_object_class_install_property
(gobject_class,
PROP_HEIGHT,
g_param_spec_double ("height", NULL, NULL,
-G_MAXDOUBLE, G_MAXDOUBLE, 0,
(G_PARAM_READABLE | G_PARAM_WRITABLE)));
g_object_class_install_property
(gobject_class,
PROP_HEIGHT_SET,
g_param_spec_boolean ("height_set", NULL, NULL,
FALSE,
(G_PARAM_READABLE | G_PARAM_WRITABLE)));
g_object_class_install_property
(gobject_class,
PROP_HEIGHT_IN_PIXELS,
g_param_spec_boolean ("height_in_pixels", NULL, NULL,
FALSE,
(G_PARAM_READABLE | G_PARAM_WRITABLE)));
g_object_class_install_property
(gobject_class,
PROP_X,
g_param_spec_double ("x", NULL, NULL,
-G_MAXDOUBLE, G_MAXDOUBLE, 0,
(G_PARAM_READABLE | G_PARAM_WRITABLE)));
g_object_class_install_property
(gobject_class,
PROP_X_IN_PIXELS,
g_param_spec_boolean ("x_in_pixels", NULL, NULL,
FALSE,
(G_PARAM_READABLE | G_PARAM_WRITABLE)));
g_object_class_install_property
(gobject_class,
PROP_Y,
g_param_spec_double ("y", NULL, NULL,
-G_MAXDOUBLE, G_MAXDOUBLE, 0,
(G_PARAM_READABLE | G_PARAM_WRITABLE)));
g_object_class_install_property
(gobject_class,
PROP_Y_IN_PIXELS,
g_param_spec_boolean ("y_in_pixels", NULL, NULL,
FALSE,
(G_PARAM_READABLE | G_PARAM_WRITABLE)));
item_class->destroy = gnome_canvas_pixbuf_destroy;
item_class->update = gnome_canvas_pixbuf_update;
item_class->draw = gnome_canvas_pixbuf_draw;
item_class->point = gnome_canvas_pixbuf_point;
item_class->bounds = gnome_canvas_pixbuf_bounds;
g_type_class_add_private (class, sizeof (GnomeCanvasPixbufPrivate));
}
/* Object initialization function for the pixbuf canvas item */
static void
gnome_canvas_pixbuf_init (GnomeCanvasPixbuf *gcp)
{
GnomeCanvasPixbufPrivate *priv;
priv = gcp->priv = G_TYPE_INSTANCE_GET_PRIVATE (gcp,
GNOME_TYPE_CANVAS_PIXBUF,
GnomeCanvasPixbufPrivate);
priv->width = 0.0;
priv->height = 0.0;
priv->x = 0.0;
priv->y = 0.0;
}
/* Destroy handler for the pixbuf canvas item */
static void
gnome_canvas_pixbuf_destroy (GnomeCanvasItem *object)
{
GnomeCanvasItem *item;
GnomeCanvasPixbuf *gcp;
GnomeCanvasPixbufPrivate *priv;
g_return_if_fail (object != NULL);
g_return_if_fail (GNOME_IS_CANVAS_PIXBUF (object));
item = GNOME_CANVAS_ITEM (object);
gcp = GNOME_CANVAS_PIXBUF (object);
priv = gcp->priv;
/* remember, destroy can be run multiple times! */
if (priv->pixbuf) {
g_object_unref (priv->pixbuf);
priv->pixbuf = NULL;
}
if (GNOME_CANVAS_ITEM_CLASS (gnome_canvas_pixbuf_parent_class)->destroy)
GNOME_CANVAS_ITEM_CLASS (gnome_canvas_pixbuf_parent_class)->destroy (object);
}
/* Set_property handler for the pixbuf canvas item */
static void
gnome_canvas_pixbuf_set_property (GObject *object,
guint param_id,
const GValue *value,
GParamSpec *pspec)
{
GnomeCanvasItem *item;
GnomeCanvasPixbuf *gcp;
GnomeCanvasPixbufPrivate *priv;
GdkPixbuf *pixbuf;
gdouble val;
g_return_if_fail (object != NULL);
g_return_if_fail (GNOME_IS_CANVAS_PIXBUF (object));
item = GNOME_CANVAS_ITEM (object);
gcp = GNOME_CANVAS_PIXBUF (object);
priv = gcp->priv;
switch (param_id) {
case PROP_PIXBUF:
pixbuf = g_value_get_object (value);
if (pixbuf != priv->pixbuf) {
if (priv->pixbuf)
g_object_unref (priv->pixbuf);
priv->pixbuf = g_object_ref (pixbuf);
}
gnome_canvas_item_request_update (item);
break;
case PROP_WIDTH:
val = g_value_get_double (value);
g_return_if_fail (val >= 0.0);
priv->width = val;
gnome_canvas_item_request_update (item);
break;
case PROP_WIDTH_SET:
priv->width_set = g_value_get_boolean (value);
gnome_canvas_item_request_update (item);
break;
case PROP_WIDTH_IN_PIXELS:
priv->width_in_pixels = g_value_get_boolean (value);
gnome_canvas_item_request_update (item);
break;
case PROP_HEIGHT:
val = g_value_get_double (value);
g_return_if_fail (val >= 0.0);
priv->height = val;
gnome_canvas_item_request_update (item);
break;
case PROP_HEIGHT_SET:
priv->height_set = g_value_get_boolean (value);
gnome_canvas_item_request_update (item);
break;
case PROP_HEIGHT_IN_PIXELS:
priv->height_in_pixels = g_value_get_boolean (value);
gnome_canvas_item_request_update (item);
break;
case PROP_X:
priv->x = g_value_get_double (value);
gnome_canvas_item_request_update (item);
break;
case PROP_X_IN_PIXELS:
priv->x_in_pixels = g_value_get_boolean (value);
gnome_canvas_item_request_update (item);
break;
case PROP_Y:
priv->y = g_value_get_double (value);
gnome_canvas_item_request_update (item);
break;
case PROP_Y_IN_PIXELS:
priv->y_in_pixels = g_value_get_boolean (value);
gnome_canvas_item_request_update (item);
break;
default:
G_OBJECT_WARN_INVALID_PROPERTY_ID (object, param_id, pspec);
break;
}
}
/* Get_property handler for the pixbuf canvasi item */
static void
gnome_canvas_pixbuf_get_property (GObject *object,
guint param_id,
GValue *value,
GParamSpec *pspec)
{
GnomeCanvasPixbuf *gcp;
GnomeCanvasPixbufPrivate *priv;
g_return_if_fail (object != NULL);
g_return_if_fail (GNOME_IS_CANVAS_PIXBUF (object));
gcp = GNOME_CANVAS_PIXBUF (object);
priv = gcp->priv;
switch (param_id) {
case PROP_PIXBUF:
g_value_set_object (value, priv->pixbuf);
break;
case PROP_WIDTH:
g_value_set_double (value, priv->width);
break;
case PROP_WIDTH_SET:
g_value_set_boolean (value, priv->width_set);
break;
case PROP_WIDTH_IN_PIXELS:
g_value_set_boolean (value, priv->width_in_pixels);
break;
case PROP_HEIGHT:
g_value_set_double (value, priv->height);
break;
case PROP_HEIGHT_SET:
g_value_set_boolean (value, priv->height_set);
break;
case PROP_HEIGHT_IN_PIXELS:
g_value_set_boolean (value, priv->height_in_pixels);
break;
case PROP_X:
g_value_set_double (value, priv->x);
break;
case PROP_X_IN_PIXELS:
g_value_set_boolean (value, priv->x_in_pixels);
break;
case PROP_Y:
g_value_set_double (value, priv->y);
break;
case PROP_Y_IN_PIXELS:
g_value_set_boolean (value, priv->y_in_pixels);
break;
default:
G_OBJECT_WARN_INVALID_PROPERTY_ID (object, param_id, pspec);
break;
}
}
/* Bounds and utilities */
/* Computes the amount by which the unit horizontal and vertical vectors will be
* scaled by an affine transformation.
*/
static void
compute_xform_scaling (gdouble *affine, ArtPoint *i_c, ArtPoint *j_c)
{
ArtPoint orig, orig_c;
ArtPoint i, j;
/* Origin */
orig.x = 0.0;
orig.y = 0.0;
art_affine_point (&orig_c, &orig, affine);
/* Horizontal and vertical vectors */
i.x = 1.0;
i.y = 0.0;
art_affine_point (i_c, &i, affine);
i_c->x -= orig_c.x;
i_c->y -= orig_c.y;
j.x = 0.0;
j.y = 1.0;
art_affine_point (j_c, &j, affine);
j_c->x -= orig_c.x;
j_c->y -= orig_c.y;
}
/* 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_viewport_affine (GnomeCanvasPixbuf *gcp,
gdouble *viewport_affine,
gdouble *i2c)
{
GnomeCanvasPixbufPrivate *priv;
ArtPoint i_c, j_c;
gdouble i_len, j_len;
gdouble si_len, sj_len;
gdouble ti_len, tj_len;
gdouble scale[6], translate[6];
gdouble w, h;
gdouble x, y;
priv = gcp->priv;
/* Compute scaling vectors and required width/height */
compute_xform_scaling (i2c, &i_c, &j_c);
i_len = sqrt (i_c.x * i_c.x + i_c.y * i_c.y);
j_len = sqrt (j_c.x * j_c.x + j_c.y * j_c.y);
if (priv->width_set)
w = priv->width;
else
w = gdk_pixbuf_get_width (priv->pixbuf);
if (priv->height_set)
h = priv->height;
else
h = gdk_pixbuf_get_height (priv->pixbuf);
x = priv->x;
y = priv->y;
/* Convert i_len and j_len into scaling factors */
if (priv->width_in_pixels) {
if (i_len > GNOME_CANVAS_EPSILON)
si_len = 1.0 / i_len;
else
si_len = 0.0;
} else
si_len = 1.0;
si_len *= w / gdk_pixbuf_get_width (priv->pixbuf);
if (priv->height_in_pixels) {
if (j_len > GNOME_CANVAS_EPSILON)
sj_len = 1.0 / j_len;
else
sj_len = 0.0;
} else
sj_len = 1.0;
sj_len *= h / gdk_pixbuf_get_height (priv->pixbuf);
/* Calculate translation offsets */
if (priv->x_in_pixels) {
if (i_len > GNOME_CANVAS_EPSILON)
ti_len = 1.0 / i_len;
else
ti_len = 0.0;
} else
ti_len = 1.0;
if (priv->y_in_pixels) {
if (j_len > GNOME_CANVAS_EPSILON)
tj_len = 1.0 / j_len;
else
tj_len = 0.0;
} else
tj_len = 1.0;
/* Compute the final affine */
art_affine_scale (scale, si_len, sj_len);
art_affine_translate (translate, ti_len, tj_len);
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, gdouble *ra, gdouble *i2c)
{
gdouble va[6];
compute_viewport_affine (gcp, va, i2c);
#ifdef GNOME_CANVAS_PIXBUF_VERBOSE
g_print ("va %g %g %g %g %g %g\n", va[0], va[1], va[2], va[3], va[4], va[5]);
#endif
art_affine_multiply (ra, va, i2c);
#ifdef GNOME_CANVAS_PIXBUF_VERBOSE
g_print ("ra %g %g %g %g %g %g\n", ra[0], ra[1], ra[2], ra[3], ra[4], ra[5]);
#endif
}
/* Recomputes the bounding box of a pixbuf canvas item. The horizontal and
* vertical dimensions may be specified in units or pixels, separately, so we
* have to compute the components individually for each dimension.
*/
static void
recompute_bounding_box (GnomeCanvasPixbuf *gcp, gdouble *i2c)
{
GnomeCanvasItem *item;
GnomeCanvasPixbufPrivate *priv;
gdouble ra[6];
ArtDRect rect;
item = GNOME_CANVAS_ITEM (gcp);
priv = gcp->priv;
if (!priv->pixbuf) {
item->x1 = item->y1 = item->x2 = item->y2 = 0.0;
return;
}
rect.x0 = 0.0;
rect.x1 = gdk_pixbuf_get_width (priv->pixbuf);
rect.y0 = 0.0;
rect.y1 = gdk_pixbuf_get_height (priv->pixbuf);
#ifdef GNOME_CANVAS_PIXBUF_VERBOSE
g_print ("i2c %g %g %g %g %g %g\n", i2c[0], i2c[1], i2c[2], i2c[3], i2c[4], i2c[5]);
#endif
gnome_canvas_item_i2c_affine (item, i2c);
#ifdef GNOME_CANVAS_PIXBUF_VERBOSE
g_print ("i2c %g %g %g %g %g %g\n", i2c[0], i2c[1], i2c[2], i2c[3], i2c[4], i2c[5]);
#endif
compute_render_affine (gcp, ra, i2c);
#ifdef GNOME_CANVAS_PIXBUF_VERBOSE
g_print ("ra %g %g %g %g %g %g\n", ra[0], ra[1], ra[2], ra[3], ra[4], ra[5]);
#endif
art_drect_affine_transform (&rect, &rect, ra);
item->x1 = floor (rect.x0);
item->y1 = floor (rect.y0);
item->x2 = ceil (rect.x1);
item->y2 = ceil (rect.y1);
}
/* Update sequence */
/* Update handler for the pixbuf canvas item */
static void
gnome_canvas_pixbuf_update (GnomeCanvasItem *item,
gdouble *affine,
ArtSVP *clip_path,
gint flags)
{
GnomeCanvasPixbuf *gcp;
GnomeCanvasPixbufPrivate *priv;
gcp = GNOME_CANVAS_PIXBUF (item);
priv = gcp->priv;
if (GNOME_CANVAS_ITEM_CLASS (gnome_canvas_pixbuf_parent_class)->update)
GNOME_CANVAS_ITEM_CLASS (gnome_canvas_pixbuf_parent_class)->update (item, affine, clip_path, flags);
/* ordinary update logic */
gnome_canvas_request_redraw (
item->canvas, item->x1, item->y1, item->x2, item->y2);
recompute_bounding_box (gcp, affine);
gnome_canvas_request_redraw (
item->canvas, item->x1, item->y1, item->x2, item->y2);
}
/* Rendering */
/* This is private to libart, but we need it. Sigh. */
extern void art_rgb_affine_run (gint *p_x0,
gint *p_x1,
gint y,
gint src_width,
gint src_height,
const gdouble affine[6]);
/* Fills the specified buffer with the transformed version of a pixbuf */
static void
transform_pixbuf (guchar *dest,
gint x,
gint y,
gint width,
gint height,
gint rowstride,
GdkPixbuf *pixbuf,
gdouble *affine)
{
gint xx, yy;
gdouble inv[6];
guchar *src, *d;
ArtPoint src_p, dest_p;
gint run_x1, run_x2;
gint src_x, src_y;
gint i;
art_affine_invert (inv, affine);
for (yy = 0; yy < height; yy++) {
dest_p.y = y + yy + 0.5;
run_x1 = x;
run_x2 = x + width;
art_rgb_affine_run (&run_x1, &run_x2, yy + y,
gdk_pixbuf_get_width (pixbuf),
gdk_pixbuf_get_height (pixbuf),
inv);
d = dest + yy * rowstride + (run_x1 - x) * 4;
for (xx = run_x1; xx < run_x2; xx++) {
dest_p.x = xx + 0.5;
art_affine_point (&src_p, &dest_p, inv);
src_x = floor (src_p.x);
src_y = floor (src_p.y);
src =
gdk_pixbuf_get_pixels (pixbuf) + src_y *
gdk_pixbuf_get_rowstride (pixbuf) + src_x *
gdk_pixbuf_get_n_channels (pixbuf);
for (i = 0; i < gdk_pixbuf_get_n_channels (pixbuf); i++)
*d++ = *src++;
if (!gdk_pixbuf_get_has_alpha (pixbuf))
*d++ = 255; /* opaque */
}
}
}
/* Draw handler for the pixbuf canvas item */
static void
gnome_canvas_pixbuf_draw (GnomeCanvasItem *item, GdkDrawable *drawable,
gint x, gint y, gint width, gint height)
{
GnomeCanvasPixbuf *gcp;
GnomeCanvasPixbufPrivate *priv;
gdouble i2c[6], render_affine[6];
guchar *buf;
GdkPixbuf *pixbuf;
ArtIRect p_rect, a_rect, d_rect;
gint w, h;
gcp = GNOME_CANVAS_PIXBUF (item);
priv = gcp->priv;
if (!priv->pixbuf)
return;
gnome_canvas_item_i2c_affine (item, i2c);
compute_render_affine (gcp, render_affine, i2c);
/* Compute the area we need to repaint */
p_rect.x0 = item->x1;
p_rect.y0 = item->y1;
p_rect.x1 = item->x2;
p_rect.y1 = item->y2;
a_rect.x0 = x;
a_rect.y0 = y;
a_rect.x1 = x + width;
a_rect.y1 = y + height;
art_irect_intersect (&d_rect, &p_rect, &a_rect);
if (art_irect_empty (&d_rect))
return;
/* Create a temporary buffer and transform the pixbuf there */
w = d_rect.x1 - d_rect.x0;
h = d_rect.y1 - d_rect.y0;
buf = g_new0 (guchar, w * h * 4);
transform_pixbuf (buf,
d_rect.x0, d_rect.y0,
w, h,
w * 4,
priv->pixbuf, render_affine);
pixbuf = gdk_pixbuf_new_from_data (buf, GDK_COLORSPACE_RGB,
TRUE,
8, w, h,
w * 4,
NULL, NULL);
gdk_draw_pixbuf (drawable, NULL, pixbuf,
0, 0,
d_rect.x0 - x, d_rect.y0 - y,
w, h,
GDK_RGB_DITHER_MAX,
d_rect.x0, d_rect.y0);
g_object_unref (pixbuf);
g_free (buf);
}
/* Point handler for the pixbuf canvas item */
static GnomeCanvasItem *
gnome_canvas_pixbuf_point (GnomeCanvasItem *item,
gdouble x,
gdouble y,
gint cx,
gint cy)
{
GnomeCanvasPixbuf *gcp;
GnomeCanvasPixbufPrivate *priv;
gdouble i2c[6], render_affine[6], inv[6];
ArtPoint c, p;
gint px, py;
gdouble no_hit;
guchar *src;
GdkPixbuf *pixbuf;
gcp = GNOME_CANVAS_PIXBUF (item);
priv = gcp->priv;
pixbuf = priv->pixbuf;
no_hit = item->canvas->pixels_per_unit * 2 + 10;
if (!priv->pixbuf)
return NULL;
gnome_canvas_item_i2c_affine (item, i2c);
compute_render_affine (gcp, render_affine, i2c);
art_affine_invert (inv, render_affine);
c.x = cx;
c.y = cy;
art_affine_point (&p, &c, inv);
px = p.x;
py = p.y;
if (px < 0 || px >= gdk_pixbuf_get_width (pixbuf) ||
py < 0 || py >= gdk_pixbuf_get_height (pixbuf))
return NULL;
if (!gdk_pixbuf_get_has_alpha (pixbuf))
return item;
src = gdk_pixbuf_get_pixels (pixbuf) +
py * gdk_pixbuf_get_rowstride (pixbuf) +
px * gdk_pixbuf_get_n_channels (pixbuf);
if (src[3] < 128)
return NULL;
else
return item;
}
/* Bounds handler for the pixbuf canvas item */
static void
gnome_canvas_pixbuf_bounds (GnomeCanvasItem *item,
gdouble *x1,
gdouble *y1,
gdouble *x2,
gdouble *y2)
{
GnomeCanvasPixbuf *gcp;
GnomeCanvasPixbufPrivate *priv;
gdouble i2c[6], viewport_affine[6];
ArtDRect rect;
gcp = GNOME_CANVAS_PIXBUF (item);
priv = gcp->priv;
if (!priv->pixbuf) {
*x1 = *y1 = *x2 = *y2 = 0.0;
return;
}
rect.x0 = 0.0;
rect.x1 = gdk_pixbuf_get_width (priv->pixbuf);
rect.y0 = 0.0;
rect.y1 = gdk_pixbuf_get_height (priv->pixbuf);
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;
}