/*
* Copyright (C) 1997, 1998, 1999, 2000 Free Software Foundation
* All rights reserved.
*
* This file is part of the Gnome Library.
*
* The Gnome 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.
*
* The Gnome 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 the Gnome Library; see the file COPYING.LIB. If not,
* write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
* Boston, MA 02111-1307, USA.
*/
/*
@NOTATION@
*/
/* Line/curve item type for GnomeCanvas widget
*
* GnomeCanvas is basically a port of the Tk toolkit's most excellent canvas widget. Tk is
* copyrighted by the Regents of the University of California, Sun Microsystems, and other parties.
*
*
* Author: Federico Mena <federico@nuclecu.unam.mx>
*/
#include <config.h>
#include <math.h>
#include <string.h>
#include <libart_lgpl/art_vpath.h>
#include <libart_lgpl/art_svp.h>
#include <libart_lgpl/art_svp_vpath.h>
#include <libart_lgpl/art_svp_vpath_stroke.h>
#include "libgnomecanvas.h"
#define noVERBOSE
#define DEFAULT_SPLINE_STEPS 12 /* this is what Tk uses */
#define NUM_ARROW_POINTS 6 /* number of points in an arrowhead */
#define NUM_STATIC_POINTS 256 /* number of static points to use to avoid allocating arrays */
#define GROW_BOUNDS(bx1, by1, bx2, by2, x, y) { \
if (x < bx1) \
bx1 = x; \
\
if (x > bx2) \
bx2 = x; \
\
if (y < by1) \
by1 = y; \
\
if (y > by2) \
by2 = y; \
}
enum {
PROP_0,
PROP_POINTS,
PROP_FILL_COLOR,
PROP_FILL_COLOR_GDK,
PROP_FILL_COLOR_RGBA,
PROP_FILL_STIPPLE,
PROP_WIDTH_PIXELS,
PROP_WIDTH_UNITS,
PROP_CAP_STYLE,
PROP_JOIN_STYLE,
PROP_LINE_STYLE,
PROP_FIRST_ARROWHEAD,
PROP_LAST_ARROWHEAD,
PROP_SMOOTH,
PROP_SPLINE_STEPS,
PROP_ARROW_SHAPE_A,
PROP_ARROW_SHAPE_B,
PROP_ARROW_SHAPE_C
};
static void gnome_canvas_line_class_init (GnomeCanvasLineClass *class);
static void gnome_canvas_line_init (GnomeCanvasLine *line);
static void gnome_canvas_line_destroy (GtkObject *object);
static void gnome_canvas_line_set_property (GObject *object,
guint param_id,
const GValue *value,
GParamSpec *pspec);
static void gnome_canvas_line_get_property (GObject *object,
guint param_id,
GValue *value,
GParamSpec *pspec);
static void gnome_canvas_line_update (GnomeCanvasItem *item, gdouble *affine, ArtSVP *clip_path, gint flags);
static void gnome_canvas_line_realize (GnomeCanvasItem *item);
static void gnome_canvas_line_unrealize (GnomeCanvasItem *item);
static void gnome_canvas_line_draw (GnomeCanvasItem *item, GdkDrawable *drawable,
gint x, gint y, gint width, gint height);
static gdouble gnome_canvas_line_point (GnomeCanvasItem *item, gdouble x, gdouble y,
gint cx, gint cy, GnomeCanvasItem **actual_item);
static void gnome_canvas_line_bounds (GnomeCanvasItem *item, gdouble *x1, gdouble *y1, gdouble *x2, gdouble *y2);
static void gnome_canvas_line_render (GnomeCanvasItem *item, GnomeCanvasBuf *buf);
static GnomeCanvasItemClass *parent_class;
GType
gnome_canvas_line_get_type (void)
{
static GType line_type;
if (!line_type) {
const GTypeInfo object_info = {
sizeof (GnomeCanvasLineClass),
(GBaseInitFunc) NULL,
(GBaseFinalizeFunc) NULL,
(GClassInitFunc) gnome_canvas_line_class_init,
(GClassFinalizeFunc) NULL,
NULL, /* class_data */
sizeof (GnomeCanvasLine),
0, /* n_preallocs */
(GInstanceInitFunc) gnome_canvas_line_init,
NULL /* value_table */
};
line_type = g_type_register_static (GNOME_TYPE_CANVAS_ITEM, "GnomeCanvasLine",
&object_info, 0);
}
return line_type;
}
static void
gnome_canvas_line_class_init (GnomeCanvasLineClass *class)
{
GObjectClass *gobject_class;
GtkObjectClass *object_class;
GnomeCanvasItemClass *item_class;
gobject_class = (GObjectClass *) class;
object_class = (GtkObjectClass *) class;
item_class = (GnomeCanvasItemClass *) class;
parent_class = g_type_class_peek_parent (class);
gobject_class->set_property = gnome_canvas_line_set_property;
gobject_class->get_property = gnome_canvas_line_get_property;
g_object_class_install_property
(gobject_class,
PROP_POINTS,
g_param_spec_boxed ("points", NULL, NULL,
GNOME_TYPE_CANVAS_POINTS,
(G_PARAM_READABLE | G_PARAM_WRITABLE)));
g_object_class_install_property
(gobject_class,
PROP_FILL_COLOR,
g_param_spec_string ("fill_color", NULL, NULL,
NULL,
(G_PARAM_READABLE | G_PARAM_WRITABLE)));
g_object_class_install_property
(gobject_class,
PROP_FILL_COLOR_GDK,
g_param_spec_boxed ("fill_color_gdk", NULL, NULL,
GDK_TYPE_COLOR,
(G_PARAM_READABLE | G_PARAM_WRITABLE)));
g_object_class_install_property
(gobject_class,
PROP_FILL_COLOR_RGBA,
g_param_spec_uint ("fill_color_rgba", NULL, NULL,
0, G_MAXUINT, 0,
(G_PARAM_READABLE | G_PARAM_WRITABLE)));
g_object_class_install_property
(gobject_class,
PROP_FILL_STIPPLE,
g_param_spec_object ("fill_stipple", NULL, NULL,
GDK_TYPE_DRAWABLE,
(G_PARAM_READABLE | G_PARAM_WRITABLE)));
g_object_class_install_property
(gobject_class,
PROP_WIDTH_PIXELS,
g_param_spec_uint ("width_pixels", NULL, NULL,
0, G_MAXUINT, 0,
(G_PARAM_READABLE | G_PARAM_WRITABLE)));
g_object_class_install_property
(gobject_class,
PROP_WIDTH_UNITS,
g_param_spec_double ("width_units", NULL, NULL,
0.0, G_MAXDOUBLE, 0.0,
(G_PARAM_READABLE | G_PARAM_WRITABLE)));
g_object_class_install_property
(gobject_class,
PROP_CAP_STYLE,
g_param_spec_enum ("cap_style", NULL, NULL,
GDK_TYPE_CAP_STYLE,
GDK_CAP_BUTT,
(G_PARAM_READABLE | G_PARAM_WRITABLE)));
g_object_class_install_property
(gobject_class,
PROP_JOIN_STYLE,
g_param_spec_enum ("join_style", NULL, NULL,
GDK_TYPE_JOIN_STYLE,
GDK_JOIN_MITER,
(G_PARAM_READABLE | G_PARAM_WRITABLE)));
g_object_class_install_property
(gobject_class,
PROP_LINE_STYLE,
g_param_spec_enum ("line_style", NULL, NULL,
GDK_TYPE_LINE_STYLE,
GDK_LINE_SOLID,
(G_PARAM_READABLE | G_PARAM_WRITABLE)));
g_object_class_install_property
(gobject_class,
PROP_FIRST_ARROWHEAD,
g_param_spec_boolean ("first_arrowhead", NULL, NULL,
FALSE,
(G_PARAM_READABLE | G_PARAM_WRITABLE)));
g_object_class_install_property
(gobject_class,
PROP_LAST_ARROWHEAD,
g_param_spec_boolean ("last_arrowhead", NULL, NULL,
FALSE,
(G_PARAM_READABLE | G_PARAM_WRITABLE)));
g_object_class_install_property
(gobject_class,
PROP_SMOOTH,
g_param_spec_boolean ("smooth", NULL, NULL,
FALSE,
(G_PARAM_READABLE | G_PARAM_WRITABLE)));
g_object_class_install_property
(gobject_class,
PROP_SPLINE_STEPS,
g_param_spec_uint ("spline_steps", NULL, NULL,
0, G_MAXUINT, DEFAULT_SPLINE_STEPS,
(G_PARAM_READABLE | G_PARAM_WRITABLE)));
g_object_class_install_property
(gobject_class,
PROP_ARROW_SHAPE_A,
g_param_spec_double ("arrow_shape_a", NULL, NULL,
-G_MAXDOUBLE, G_MAXDOUBLE, 0,
(G_PARAM_READABLE | G_PARAM_WRITABLE)));
g_object_class_install_property
(gobject_class,
PROP_ARROW_SHAPE_B,
g_param_spec_double ("arrow_shape_b", NULL, NULL,
-G_MAXDOUBLE, G_MAXDOUBLE, 0,
(G_PARAM_READABLE | G_PARAM_WRITABLE)));
g_object_class_install_property
(gobject_class,
PROP_ARROW_SHAPE_C,
g_param_spec_double ("arrow_shape_c", NULL, NULL,
-G_MAXDOUBLE, G_MAXDOUBLE, 0,
(G_PARAM_READABLE | G_PARAM_WRITABLE)));
object_class->destroy = gnome_canvas_line_destroy;
item_class->update = gnome_canvas_line_update;
item_class->realize = gnome_canvas_line_realize;
item_class->unrealize = gnome_canvas_line_unrealize;
item_class->draw = gnome_canvas_line_draw;
item_class->point = gnome_canvas_line_point;
item_class->bounds = gnome_canvas_line_bounds;
item_class->render = gnome_canvas_line_render;
}
static void
gnome_canvas_line_init (GnomeCanvasLine *line)
{
line->width = 0.0;
line->cap = GDK_CAP_BUTT;
line->join = GDK_JOIN_MITER;
line->line_style = GDK_LINE_SOLID;
line->shape_a = 0.0;
line->shape_b = 0.0;
line->shape_c = 0.0;
line->spline_steps = DEFAULT_SPLINE_STEPS;
}
static void
gnome_canvas_line_destroy (GtkObject *object)
{
GnomeCanvasLine *line;
g_return_if_fail (object != NULL);
g_return_if_fail (GNOME_IS_CANVAS_LINE (object));
line = GNOME_CANVAS_LINE (object);
/* remember, destroy can be run multiple times! */
if (line->coords)
g_free (line->coords);
line->coords = NULL;
if (line->first_coords)
g_free (line->first_coords);
line->first_coords = NULL;
if (line->last_coords)
g_free (line->last_coords);
line->last_coords = NULL;
if (line->stipple)
g_object_unref (line->stipple);
line->stipple = NULL;
if (line->fill_svp)
art_svp_free (line->fill_svp);
line->fill_svp = NULL;
if (line->first_svp)
art_svp_free (line->first_svp);
line->first_svp = NULL;
if (line->last_svp)
art_svp_free (line->last_svp);
line->last_svp = NULL;
if (GTK_OBJECT_CLASS (parent_class)->destroy)
(* GTK_OBJECT_CLASS (parent_class)->destroy) (object);
}
/* Computes the bounding box of the line, including its arrow points. Assumes that the number of
* points in the line is not zero.
*/
static void
get_bounds (GnomeCanvasLine *line, gdouble *bx1, gdouble *by1, gdouble *bx2, gdouble *by2)
{
gdouble *coords;
gdouble x1, y1, x2, y2;
gdouble width;
gint i;
if (!line->coords) {
*bx1 = *by1 = *bx2 = *by2 = 0.0;
return;
}
/* Find bounding box of line's points */
x1 = x2 = line->coords[0];
y1 = y2 = line->coords[1];
for (i = 1, coords = line->coords + 2; i < line->num_points; i++, coords += 2)
GROW_BOUNDS (x1, y1, x2, y2, coords[0], coords[1]);
/* Add possible over-estimate for wide lines */
if (line->width_pixels)
width = line->width / line->item.canvas->pixels_per_unit;
else
width = line->width;
x1 -= width;
y1 -= width;
x2 += width;
y2 += width;
/* For mitered lines, make a second pass through all the points. Compute the location of
* the two miter vertex points and add them to the bounding box.
*/
if (line->join == GDK_JOIN_MITER)
for (i = line->num_points, coords = line->coords; i >= 3; i--, coords += 2) {
gdouble mx1, my1, mx2, my2;
if (gnome_canvas_get_miter_points (coords[0], coords[1],
coords[2], coords[3],
coords[4], coords[5],
width,
&mx1, &my1, &mx2, &my2)) {
GROW_BOUNDS (x1, y1, x2, y2, mx1, my1);
GROW_BOUNDS (x1, y1, x2, y2, mx2, my2);
}
}
/* Add the arrow points, if any */
if (line->first_arrow && line->first_coords)
for (i = 0, coords = line->first_coords; i < NUM_ARROW_POINTS; i++, coords += 2)
GROW_BOUNDS (x1, y1, x2, y2, coords[0], coords[1]);
if (line->last_arrow && line->last_coords)
for (i = 0, coords = line->last_coords; i < NUM_ARROW_POINTS; i++, coords += 2)
GROW_BOUNDS (x1, y1, x2, y2, coords[0], coords[1]);
/* Done */
*bx1 = x1;
*by1 = y1;
*bx2 = x2;
*by2 = y2;
}
/* Computes the bounding box of the line, in canvas coordinates. Assumes that the number of points in the polygon is
* not zero. Affine is the i2c transformation.
*/
static void
get_bounds_canvas (GnomeCanvasLine *line, gdouble *bx1, gdouble *by1, gdouble *bx2, gdouble *by2, gdouble affine[6])
{
/* It would be possible to tighten the bounds somewhat by transforming the individual points before
aggregating them into the bbox. But it hardly seems worth it. */
ArtDRect bbox_world;
ArtDRect bbox_canvas;
get_bounds (line, &bbox_world.x0, &bbox_world.y0, &bbox_world.x1, &bbox_world.y1);
art_drect_affine_transform (&bbox_canvas, &bbox_world, affine);
/* include 1 pixel of fudge */
*bx1 = bbox_canvas.x0 - 1;
*by1 = bbox_canvas.y0 - 1;
*bx2 = bbox_canvas.x1 + 1;
*by2 = bbox_canvas.y1 + 1;
}
/* Recalculates the arrow polygons for the line */
static void
reconfigure_arrows (GnomeCanvasLine *line)
{
gdouble *poly, *coords;
gdouble dx, dy, length;
gdouble sin_theta, cos_theta, tmp;
gdouble frac_height; /* Line width as fraction of arrowhead width */
gdouble backup; /* Distance to backup end points so the line ends in the middle of the arrowhead */
gdouble vx, vy; /* Position of arrowhead vertex */
gdouble shape_a, shape_b, shape_c;
gdouble width;
gint i;
if (line->num_points == 0)
return;
/* Set up things */
if (line->first_arrow) {
if (line->first_coords) {
line->coords[0] = line->first_coords[0];
line->coords[1] = line->first_coords[1];
} else
line->first_coords = g_new (double, 2 * NUM_ARROW_POINTS);
} else if (line->first_coords) {
line->coords[0] = line->first_coords[0];
line->coords[1] = line->first_coords[1];
g_free (line->first_coords);
line->first_coords = NULL;
}
i = 2 * (line->num_points - 1);
if (line->last_arrow) {
if (line->last_coords) {
line->coords[i] = line->last_coords[0];
line->coords[i + 1] = line->last_coords[1];
} else
line->last_coords = g_new (double, 2 * NUM_ARROW_POINTS);
} else if (line->last_coords) {
line->coords[i] = line->last_coords[0];
line->coords[i + 1] = line->last_coords[1];
g_free (line->last_coords);
line->last_coords = NULL;
}
if (!line->first_arrow && !line->last_arrow)
return;
if (line->width_pixels)
width = line->width / line->item.canvas->pixels_per_unit;
else
width = line->width;
/* Add fudge value for better-looking results */
shape_a = line->shape_a;
shape_b = line->shape_b;
shape_c = line->shape_c + width / 2.0;
if (line->width_pixels) {
shape_a /= line->item.canvas->pixels_per_unit;
shape_b /= line->item.canvas->pixels_per_unit;
shape_c /= line->item.canvas->pixels_per_unit;
}
shape_a += 0.001;
shape_b += 0.001;
shape_c += 0.001;
/* Compute the polygon for the first arrowhead and adjust the first point in the line so
* that the line does not stick out past the leading edge of the arrowhead.
*/
frac_height = (line->width / 2.0) / shape_c;
backup = frac_height * shape_b + shape_a * (1.0 - frac_height) / 2.0;
if (line->first_arrow) {
poly = line->first_coords;
poly[0] = poly[10] = line->coords[0];
poly[1] = poly[11] = line->coords[1];
dx = poly[0] - line->coords[2];
dy = poly[1] - line->coords[3];
length = sqrt (dx * dx + dy * dy);
if (length < GNOME_CANVAS_EPSILON)
sin_theta = cos_theta = 0.0;
else {
sin_theta = dy / length;
cos_theta = dx / length;
}
vx = poly[0] - shape_a * cos_theta;
vy = poly[1] - shape_a * sin_theta;
tmp = shape_c * sin_theta;
poly[2] = poly[0] - shape_b * cos_theta + tmp;
poly[8] = poly[2] - 2.0 * tmp;
tmp = shape_c * cos_theta;
poly[3] = poly[1] - shape_b * sin_theta - tmp;
poly[9] = poly[3] + 2.0 * tmp;
poly[4] = poly[2] * frac_height + vx * (1.0 - frac_height);
poly[5] = poly[3] * frac_height + vy * (1.0 - frac_height);
poly[6] = poly[8] * frac_height + vx * (1.0 - frac_height);
poly[7] = poly[9] * frac_height + vy * (1.0 - frac_height);
/* Move the first point towards the second so that the corners at the end of the
* line are inside the arrowhead.
*/
line->coords[0] = poly[0] - backup * cos_theta;
line->coords[1] = poly[1] - backup * sin_theta;
}
/* Same process for last arrowhead */
if (line->last_arrow) {
coords = line->coords + 2 * (line->num_points - 2);
poly = line->last_coords;
poly[0] = poly[10] = coords[2];
poly[1] = poly[11] = coords[3];
dx = poly[0] - coords[0];
dy = poly[1] - coords[1];
length = sqrt (dx * dx + dy * dy);
if (length < GNOME_CANVAS_EPSILON)
sin_theta = cos_theta = 0.0;
else {
sin_theta = dy / length;
cos_theta = dx / length;
}
vx = poly[0] - shape_a * cos_theta;
vy = poly[1] - shape_a * sin_theta;
tmp = shape_c * sin_theta;
poly[2] = poly[0] - shape_b * cos_theta + tmp;
poly[8] = poly[2] - 2.0 * tmp;
tmp = shape_c * cos_theta;
poly[3] = poly[1] - shape_b * sin_theta - tmp;
poly[9] = poly[3] + 2.0 * tmp;
poly[4] = poly[2] * frac_height + vx * (1.0 - frac_height);
poly[5] = poly[3] * frac_height + vy * (1.0 - frac_height);
poly[6] = poly[8] * frac_height + vx * (1.0 - frac_height);
poly[7] = poly[9] * frac_height + vy * (1.0 - frac_height);
coords[2] = poly[0] - backup * cos_theta;
coords[3] = poly[1] - backup * sin_theta;
}
}
/* Convenience function to set the line's GC's foreground color */
static void
set_line_gc_foreground (GnomeCanvasLine *line)
{
GdkColor c;
if (!line->gc)
return;
c.pixel = line->fill_pixel;
gdk_gc_set_foreground (line->gc, &c);
}
/* Recalculate the line's width and set it in its GC */
static void
set_line_gc_width (GnomeCanvasLine *line)
{
gint width;
if (!line->gc)
return;
if (line->width_pixels)
width = (gint) line->width;
else
width = (gint) (line->width * line->item.canvas->pixels_per_unit + 0.5);
gdk_gc_set_line_attributes (line->gc,
width,
line->line_style,
(line->first_arrow || line->last_arrow) ? GDK_CAP_BUTT : line->cap,
line->join);
}
/* Sets the stipple pattern for the line */
static void
set_stipple (GnomeCanvasLine *line, GdkBitmap *stipple, gint reconfigure)
{
if (line->stipple && !reconfigure)
g_object_unref (line->stipple);
line->stipple = stipple;
if (stipple && !reconfigure)
g_object_ref (stipple);
if (line->gc) {
if (stipple) {
gdk_gc_set_stipple (line->gc, stipple);
gdk_gc_set_fill (line->gc, GDK_STIPPLED);
} else
gdk_gc_set_fill (line->gc, GDK_SOLID);
}
}
static void
gnome_canvas_line_set_property (GObject *object,
guint param_id,
const GValue *value,
GParamSpec *pspec)
{
GnomeCanvasItem *item;
GnomeCanvasLine *line;
GnomeCanvasPoints *points;
GdkColor color = { 0, 0, 0, 0, };
GdkColor *pcolor;
gboolean color_changed;
gint have_pixel;
g_return_if_fail (object != NULL);
g_return_if_fail (GNOME_IS_CANVAS_LINE (object));
item = GNOME_CANVAS_ITEM (object);
line = GNOME_CANVAS_LINE (object);
color_changed = FALSE;
have_pixel = FALSE;
switch (param_id) {
case PROP_POINTS:
points = g_value_get_boxed (value);
if (line->coords) {
g_free (line->coords);
line->coords = NULL;
}
if (!points)
line->num_points = 0;
else {
line->num_points = points->num_points;
line->coords = g_new (double, 2 * line->num_points);
memcpy (line->coords, points->coords, 2 * line->num_points * sizeof (gdouble));
}
/* Drop the arrowhead polygons if they exist -- they will be regenerated */
if (line->first_coords) {
g_free (line->first_coords);
line->first_coords = NULL;
}
if (line->last_coords) {
g_free (line->last_coords);
line->last_coords = NULL;
}
/* Since the line's points have changed, we need to re-generate arrowheads in
* addition to recalculating the bounds.
*/
gnome_canvas_item_request_update (item);
break;
case PROP_FILL_COLOR:
if (g_value_get_string (value))
gdk_color_parse (g_value_get_string (value), &color);
line->fill_rgba = ((color.red & 0xff00) << 16 |
(color.green & 0xff00) << 8 |
(color.blue & 0xff00) |
0xff);
color_changed = TRUE;
break;
case PROP_FILL_COLOR_GDK:
pcolor = g_value_get_boxed (value);
if (pcolor) {
GdkColormap *colormap;
color = *pcolor;
colormap = gtk_widget_get_colormap (GTK_WIDGET (item->canvas));
gdk_rgb_find_color (colormap, &color);
have_pixel = TRUE;
}
line->fill_rgba = ((color.red & 0xff00) << 16 |
(color.green & 0xff00) << 8 |
(color.blue & 0xff00) |
0xff);
color_changed = TRUE;
break;
case PROP_FILL_COLOR_RGBA:
line->fill_rgba = g_value_get_uint (value);
color_changed = TRUE;
break;
case PROP_FILL_STIPPLE:
set_stipple (line, (GdkBitmap *) g_value_get_object (value), FALSE);
gnome_canvas_item_request_redraw_svp (item, line->fill_svp);
break;
case PROP_WIDTH_PIXELS:
line->width = g_value_get_uint (value);
line->width_pixels = TRUE;
set_line_gc_width (line);
gnome_canvas_item_request_update (item);
break;
case PROP_WIDTH_UNITS:
line->width = fabs (g_value_get_double (value));
line->width_pixels = FALSE;
set_line_gc_width (line);
gnome_canvas_item_request_update (item);
break;
case PROP_CAP_STYLE:
line->cap = g_value_get_enum (value);
gnome_canvas_item_request_update (item);
break;
case PROP_JOIN_STYLE:
line->join = g_value_get_enum (value);
gnome_canvas_item_request_update (item);
break;
case PROP_LINE_STYLE:
line->line_style = g_value_get_enum (value);
set_line_gc_width (line);
gnome_canvas_item_request_update (item);
break;
case PROP_FIRST_ARROWHEAD:
line->first_arrow = g_value_get_boolean (value);
gnome_canvas_item_request_update (item);
break;
case PROP_LAST_ARROWHEAD:
line->last_arrow = g_value_get_boolean (value);
gnome_canvas_item_request_update (item);
break;
case PROP_SMOOTH:
/* FIXME */
break;
case PROP_SPLINE_STEPS:
/* FIXME */
break;
case PROP_ARROW_SHAPE_A:
line->shape_a = fabs (g_value_get_double (value));
gnome_canvas_item_request_update (item);
break;
case PROP_ARROW_SHAPE_B:
line->shape_b = fabs (g_value_get_double (value));
gnome_canvas_item_request_update (item);
break;
case PROP_ARROW_SHAPE_C:
line->shape_c = fabs (g_value_get_double (value));
gnome_canvas_item_request_update (item);
break;
default:
G_OBJECT_WARN_INVALID_PROPERTY_ID (object, param_id, pspec);
break;
}
if (color_changed) {
if (have_pixel)
line->fill_pixel = color.pixel;
else
line->fill_pixel = gnome_canvas_get_color_pixel (item->canvas,
line->fill_rgba);
if (!item->canvas->aa)
set_line_gc_foreground (line);
gnome_canvas_item_request_redraw_svp (item, line->fill_svp);
if (line->first_svp)
gnome_canvas_item_request_redraw_svp (item, line->first_svp);
if (line->last_svp)
gnome_canvas_item_request_redraw_svp (item, line->last_svp);
}
}
/* Returns a copy of the line's points without the endpoint adjustments for
* arrowheads.
*/
static GnomeCanvasPoints *
get_points (GnomeCanvasLine *line)
{
GnomeCanvasPoints *points;
gint start_ofs, end_ofs;
if (line->num_points == 0)
return NULL;
start_ofs = end_ofs = 0;
points = gnome_canvas_points_new (line->num_points);
/* Invariant: if first_coords or last_coords exist, then the line's
* endpoints have been adjusted.
*/
if (line->first_coords) {
start_ofs = 1;
points->coords[0] = line->first_coords[0];
points->coords[1] = line->first_coords[1];
}
if (line->last_coords) {
end_ofs = 1;
points->coords[2 * (line->num_points - 1)] = line->last_coords[0];
points->coords[2 * (line->num_points - 1) + 1] = line->last_coords[1];
}
memcpy (points->coords + 2 * start_ofs,
line->coords + 2 * start_ofs,
2 * (line->num_points - (start_ofs + end_ofs)) * sizeof (gdouble));
return points;
}
static void
gnome_canvas_line_get_property (GObject *object,
guint param_id,
GValue *value,
GParamSpec *pspec)
{
GnomeCanvasLine *line;
g_return_if_fail (object != NULL);
g_return_if_fail (GNOME_IS_CANVAS_LINE (object));
line = GNOME_CANVAS_LINE (object);
switch (param_id) {
case PROP_POINTS:
/* get_points returns a copy */
g_value_take_boxed (value, get_points (line));
break;
case PROP_FILL_COLOR:
g_value_take_string (value,
g_strdup_printf ("#%02x%02x%02x",
line->fill_rgba >> 24,
(line->fill_rgba >> 16) & 0xff,
(line->fill_rgba >> 8) & 0xff));
break;
case PROP_FILL_COLOR_GDK: {
GnomeCanvas *canvas = GNOME_CANVAS_ITEM (line)->canvas;
GdkColormap *colormap = gtk_widget_get_colormap (GTK_WIDGET (canvas));
GdkColor color;
gdk_colormap_query_color (colormap, line->fill_pixel, &color);
g_value_set_boxed (value, &color);
break;
}
case PROP_FILL_COLOR_RGBA:
g_value_set_uint (value, line->fill_rgba);
break;
case PROP_FILL_STIPPLE:
g_value_set_object (value, line->stipple);
break;
case PROP_WIDTH_PIXELS:
g_value_set_uint (value, line->width);
break;
case PROP_WIDTH_UNITS:
g_value_set_double (value, line->width);
break;
case PROP_CAP_STYLE:
g_value_set_enum (value, line->cap);
break;
case PROP_JOIN_STYLE:
g_value_set_enum (value, line->join);
break;
case PROP_LINE_STYLE:
g_value_set_enum (value, line->line_style);
break;
case PROP_FIRST_ARROWHEAD:
g_value_set_boolean (value, line->first_arrow);
break;
case PROP_LAST_ARROWHEAD:
g_value_set_boolean (value, line->last_arrow);
break;
case PROP_SMOOTH:
g_value_set_boolean (value, line->smooth);
break;
case PROP_SPLINE_STEPS:
g_value_set_uint (value, line->spline_steps);
break;
case PROP_ARROW_SHAPE_A:
g_value_set_double (value, line->shape_a);
break;
case PROP_ARROW_SHAPE_B:
g_value_set_double (value, line->shape_b);
break;
case PROP_ARROW_SHAPE_C:
g_value_set_double (value, line->shape_c);
break;
default:
G_OBJECT_WARN_INVALID_PROPERTY_ID (object, param_id, pspec);
break;
}
}
static void
gnome_canvas_line_render (GnomeCanvasItem *item,
GnomeCanvasBuf *buf)
{
GnomeCanvasLine *line;
line = GNOME_CANVAS_LINE (item);
if (line->fill_svp != NULL)
gnome_canvas_render_svp (buf, line->fill_svp, line->fill_rgba);
if (line->first_svp != NULL)
gnome_canvas_render_svp (buf, line->first_svp, line->fill_rgba);
if (line->last_svp != NULL)
gnome_canvas_render_svp (buf, line->last_svp, line->fill_rgba);
}
static ArtSVP *
svp_from_points (const gdouble *item_coords, gint num_points, const gdouble affine[6])
{
ArtVpath *vpath;
ArtSVP *svp;
gdouble x, y;
gint i;
vpath = art_new (ArtVpath, num_points + 2);
for (i = 0; i < num_points; i++) {
vpath[i].code = i == 0 ? ART_MOVETO : ART_LINETO;
x = item_coords[i * 2];
y = item_coords[i * 2 + 1];
vpath[i].x = x * affine[0] + y * affine[2] + affine[4];
vpath[i].y = x * affine[1] + y * affine[3] + affine[5];
}
#if 0
vpath[i].code = ART_LINETO;
vpath[i].x = vpath[0].x;
vpath[i].y = vpath[0].y;
i++;
#endif
vpath[i].code = ART_END;
vpath[i].x = 0;
vpath[i].y = 0;
svp = art_svp_from_vpath (vpath);
art_free (vpath);
return svp;
}
static void
gnome_canvas_line_update (GnomeCanvasItem *item, gdouble *affine, ArtSVP *clip_path, gint flags)
{
GnomeCanvasLine *line;
gint i;
ArtVpath *vpath;
ArtPoint pi, pc;
gdouble width;
ArtSVP *svp;
gdouble x1, y1, x2, y2;
line = GNOME_CANVAS_LINE (item);
if (parent_class->update)
(* parent_class->update) (item, affine, clip_path, flags);
reconfigure_arrows (line);
if (item->canvas->aa) {
gnome_canvas_item_reset_bounds (item);
vpath = art_new (ArtVpath, line->num_points + 2);
for (i = 0; i < line->num_points; i++) {
pi.x = line->coords[i * 2];
pi.y = line->coords[i * 2 + 1];
art_affine_point (&pc, &pi, affine);
vpath[i].code = i == 0 ? ART_MOVETO : ART_LINETO;
vpath[i].x = pc.x;
vpath[i].y = pc.y;
}
vpath[i].code = ART_END;
vpath[i].x = 0;
vpath[i].y = 0;
if (line->width_pixels)
width = line->width;
else
width = line->width * art_affine_expansion (affine);
if (width < 0.5)
width = 0.5;
svp = art_svp_vpath_stroke (vpath,
gnome_canvas_join_gdk_to_art (line->join),
gnome_canvas_cap_gdk_to_art (line->cap),
width,
4,
0.25);
art_free (vpath);
gnome_canvas_item_update_svp_clip (item, &line->fill_svp, svp, clip_path);
if (line->first_arrow && line->first_coords) {
svp = svp_from_points (line->first_coords, NUM_ARROW_POINTS, affine);
gnome_canvas_item_update_svp_clip (item,
&line->first_svp, svp, clip_path);
}
if (line->last_arrow && line->last_coords) {
svp = svp_from_points (line->last_coords, NUM_ARROW_POINTS, affine);
gnome_canvas_item_update_svp_clip (item,
&line->last_svp, svp, clip_path);
}
} else {
set_line_gc_foreground (line);
set_line_gc_width (line);
set_stipple (line, line->stipple, TRUE);
get_bounds_canvas (line, &x1, &y1, &x2, &y2, affine);
gnome_canvas_update_bbox (item, x1, y1, x2, y2);
}
}
static void
gnome_canvas_line_realize (GnomeCanvasItem *item)
{
GtkLayout *layout;
GnomeCanvasLine *line;
GdkWindow *bin_window;
line = GNOME_CANVAS_LINE (item);
if (parent_class->realize)
(* parent_class->realize) (item);
layout = GTK_LAYOUT (item->canvas);
bin_window = gtk_layout_get_bin_window (layout);
line->gc = gdk_gc_new (bin_window);
#if 0
(* GNOME_CANVAS_ITEM_CLASS (item->object.klass)->update) (item, NULL, NULL, 0);
#endif
}
static void
gnome_canvas_line_unrealize (GnomeCanvasItem *item)
{
GnomeCanvasLine *line;
line = GNOME_CANVAS_LINE (item);
g_object_unref (line->gc);
line->gc = NULL;
if (parent_class->unrealize)
(* parent_class->unrealize) (item);
}
static void
item_to_canvas (GnomeCanvas *canvas, gdouble *item_coords, GdkPoint *canvas_coords, gint num_points,
gint *num_drawn_points, gdouble i2c[6], gint x, gint y)
{
gint i;
gint old_cx, old_cy;
gint cx, cy;
ArtPoint pi, pc;
#ifdef VERBOSE
{
gchar str[128];
art_affine_to_string (str, i2c);
g_print ("line item_to_canvas %s\n", str);
}
#endif
/* the first point is always drawn */
pi.x = item_coords[0];
pi.y = item_coords[1];
art_affine_point (&pc, &pi, i2c);
cx = floor (pc.x + 0.5);
cy = floor (pc.y + 0.5);
canvas_coords->x = cx - x;
canvas_coords->y = cy - y;
canvas_coords++;
old_cx = cx;
old_cy = cy;
*num_drawn_points = 1;
for (i = 1; i < num_points; i++) {
pi.x = item_coords[i * 2];
pi.y = item_coords[i * 2 + 1];
art_affine_point (&pc, &pi, i2c);
cx = floor (pc.x + 0.5);
cy = floor (pc.y + 0.5);
if (old_cx != cx || old_cy != cy) {
canvas_coords->x = cx - x;
canvas_coords->y = cy - y;
old_cx = cx;
old_cy = cy;
canvas_coords++;
(*num_drawn_points)++;
}
}
}
static void
gnome_canvas_line_draw (GnomeCanvasItem *item, GdkDrawable *drawable,
gint x, gint y, gint width, gint height)
{
GnomeCanvasLine *line;
GdkPoint static_points[NUM_STATIC_POINTS];
GdkPoint *points;
gint actual_num_points_drawn;
gdouble i2c[6];
line = GNOME_CANVAS_LINE (item);
if (line->num_points == 0)
return;
/* Build array of canvas pixel coordinates */
if (line->num_points <= NUM_STATIC_POINTS)
points = static_points;
else
points = g_new (GdkPoint, line->num_points);
gnome_canvas_item_i2c_affine (item, i2c);
item_to_canvas (item->canvas, line->coords, points, line->num_points,
&actual_num_points_drawn, i2c, x, y);
if (line->stipple)
gnome_canvas_set_stipple_origin (item->canvas, line->gc);
gdk_draw_lines (drawable, line->gc, points, actual_num_points_drawn);
if (points != static_points)
g_free (points);
/* Draw arrowheads */
points = static_points;
if (line->first_arrow) {
item_to_canvas (item->canvas, line->first_coords, points, NUM_ARROW_POINTS,
&actual_num_points_drawn, i2c, x, y);
gdk_draw_polygon (drawable, line->gc, TRUE, points, actual_num_points_drawn );
}
if (line->last_arrow) {
item_to_canvas (item->canvas, line->last_coords, points, NUM_ARROW_POINTS,
&actual_num_points_drawn, i2c, x, y);
gdk_draw_polygon (drawable, line->gc, TRUE, points, actual_num_points_drawn );
}
}
static double
gnome_canvas_line_point (GnomeCanvasItem *item, gdouble x, gdouble y,
gint cx, gint cy, GnomeCanvasItem **actual_item)
{
GnomeCanvasLine *line;
gdouble *line_points = NULL, *coords;
gdouble static_points[2 * NUM_STATIC_POINTS];
gdouble poly[10];
gdouble best, dist;
gdouble dx, dy;
gdouble width;
gint num_points = 0, i;
gint changed_miter_to_bevel;
#ifdef VERBOSE
g_print ("gnome_canvas_line_point x, y = (%g, %g); cx, cy = (%d, %d)\n", x, y, cx, cy);
#endif
line = GNOME_CANVAS_LINE (item);
*actual_item = item;
best = 1.0e36;
/* Handle smoothed lines by generating an expanded set ot points */
if (line->smooth && (line->num_points > 2)) {
/* FIXME */
} else {
num_points = line->num_points;
line_points = line->coords;
}
/* Compute a polygon for each edge of the line and test the point against it. The effective
* width of the line is adjusted so that it will be at least one pixel thick (so that zero
* pixel-wide lines can be pickedup as well).
*/
if (line->width_pixels)
width = line->width / item->canvas->pixels_per_unit;
else
width = line->width;
if (width < (1.0 / item->canvas->pixels_per_unit))
width = 1.0 / item->canvas->pixels_per_unit;
changed_miter_to_bevel = 0;
for (i = num_points, coords = line_points; i >= 2; i--, coords += 2) {
/* If rounding is done around the first point, then compute distance between the
* point and the first point.
*/
if (((line->cap == GDK_CAP_ROUND) && (i == num_points))
|| ((line->join == GDK_JOIN_ROUND) && (i != num_points))) {
dx = coords[0] - x;
dy = coords[1] - y;
dist = sqrt (dx * dx + dy * dy) - width / 2.0;
if (dist < GNOME_CANVAS_EPSILON) {
best = 0.0;
goto done;
} else if (dist < best)
best = dist;
}
/* Compute the polygonal shape corresponding to this edge, with two points for the
* first point of the edge and two points for the last point of the edge.
*/
if (i == num_points)
gnome_canvas_get_butt_points (coords[2], coords[3], coords[0], coords[1],
width, (line->cap == GDK_CAP_PROJECTING),
poly, poly + 1, poly + 2, poly + 3);
else if ((line->join == GDK_JOIN_MITER) && !changed_miter_to_bevel) {
poly[0] = poly[6];
poly[1] = poly[7];
poly[2] = poly[4];
poly[3] = poly[5];
} else {
gnome_canvas_get_butt_points (coords[2], coords[3], coords[0], coords[1],
width, FALSE,
poly, poly + 1, poly + 2, poly + 3);
/* If this line uses beveled joints, then check the distance to a polygon
* comprising the last two points of the previous polygon and the first two
* from this polygon; this checks the wedges that fill the mitered point.
*/
if ((line->join == GDK_JOIN_BEVEL) || changed_miter_to_bevel) {
poly[8] = poly[0];
poly[9] = poly[1];
dist = gnome_canvas_polygon_to_point (poly, 5, x, y);
if (dist < GNOME_CANVAS_EPSILON) {
best = 0.0;
goto done;
} else if (dist < best)
best = dist;
changed_miter_to_bevel = FALSE;
}
}
if (i == 2)
gnome_canvas_get_butt_points (coords[0], coords[1], coords[2], coords[3],
width, (line->cap == GDK_CAP_PROJECTING),
poly + 4, poly + 5, poly + 6, poly + 7);
else if (line->join == GDK_JOIN_MITER) {
if (!gnome_canvas_get_miter_points (coords[0], coords[1],
coords[2], coords[3],
coords[4], coords[5],
width,
poly + 4, poly + 5, poly + 6, poly + 7)) {
changed_miter_to_bevel = TRUE;
gnome_canvas_get_butt_points (coords[0], coords[1], coords[2], coords[3],
width, FALSE,
poly + 4, poly + 5, poly + 6, poly + 7);
}
} else
gnome_canvas_get_butt_points (coords[0], coords[1], coords[2], coords[3],
width, FALSE,
poly + 4, poly + 5, poly + 6, poly + 7);
poly[8] = poly[0];
poly[9] = poly[1];
dist = gnome_canvas_polygon_to_point (poly, 5, x, y);
if (dist < GNOME_CANVAS_EPSILON) {
best = 0.0;
goto done;
} else if (dist < best)
best = dist;
}
/* If caps are rounded, check the distance to the cap around the final end point of the line */
if (line->cap == GDK_CAP_ROUND) {
dx = coords[0] - x;
dy = coords[1] - y;
dist = sqrt (dx * dx + dy * dy) - width / 2.0;
if (dist < GNOME_CANVAS_EPSILON) {
best = 0.0;
goto done;
} else
best = dist;
}
/* sometimes the GnomeCanvasItem::update signal will not have
been processed between deleting the arrow points and a call
to this routine -- this can cause a segfault here */
if ((line->first_arrow && !line->first_coords) ||
(line->last_arrow && !line->last_coords))
reconfigure_arrows (line);
/* If there are arrowheads, check the distance to them */
if (line->first_arrow) {
dist = gnome_canvas_polygon_to_point (line->first_coords, NUM_ARROW_POINTS, x, y);
if (dist < GNOME_CANVAS_EPSILON) {
best = 0.0;
goto done;
} else
best = dist;
}
if (line->last_arrow) {
dist = gnome_canvas_polygon_to_point (line->last_coords, NUM_ARROW_POINTS, x, y);
if (dist < GNOME_CANVAS_EPSILON) {
best = 0.0;
goto done;
} else
best = dist;
}
done:
if ((line_points != static_points) && (line_points != line->coords))
g_free (line_points);
return best;
}
static void
gnome_canvas_line_bounds (GnomeCanvasItem *item, gdouble *x1, gdouble *y1, gdouble *x2, gdouble *y2)
{
GnomeCanvasLine *line;
line = GNOME_CANVAS_LINE (item);
if (line->num_points == 0) {
*x1 = *y1 = *x2 = *y2 = 0.0;
return;
}
get_bounds (line, x1, y1, x2, y2);
}
