static void
goc_line_get_property (GObject *gobject, guint param_id,
GValue *value, GParamSpec *pspec)
{
GocLine *line = GOC_LINE (gobject);
switch (param_id) {
case LINE_PROP_X0:
g_value_set_double (value, line->startx);
break;
case LINE_PROP_Y0:
g_value_set_double (value, line->starty);
break;
case LINE_PROP_X1:
g_value_set_double (value, line->endx);
break;
case LINE_PROP_Y1:
g_value_set_double (value, line->endy);
break;
case LINE_PROP_START_ARROW:
g_value_set_boxed (value, &line->start_arrow);
break;
case LINE_PROP_END_ARROW:
g_value_set_boxed (value, &line->end_arrow);
break;
default: G_OBJECT_WARN_INVALID_PROPERTY_ID (gobject, param_id, pspec);
return; /* NOTE : RETURN */
}
}
static void
goc_line_update_bounds (GocItem *item)
{
GocLine *line = GOC_LINE (item);
GOStyle *style = go_styled_object_get_style (GO_STYLED_OBJECT (item));
double extra_width = style->line.width /2.;
/* FIXME: take transform into account */
if (extra_width <= 0.)
extra_width = .5;
if (style->line.cap == CAIRO_LINE_CAP_SQUARE)
extra_width *= 1.5; /* 1.4142 should be enough */
if (line->startx < line->endx) {
item->x0 = line->startx - extra_width;
item->x1 = line->endx + extra_width;
} else {
item->x0 = line->endx - extra_width;
item->x1 = line->startx + extra_width;
}
if (line->starty < line->endy) {
item->y0 = line->starty - extra_width;
item->y1 = line->endy + extra_width;
} else {
item->y0 = line->endy - extra_width;
item->y1 = line->starty + extra_width;
}
handle_arrow_bounds (&line->start_arrow, item);
handle_arrow_bounds (&line->end_arrow, item);
}
static void
goc_line_draw (GocItem const *item, cairo_t *cr)
{
GocLine *line = GOC_LINE (item);
GOStyle *style = go_styled_object_get_style (GO_STYLED_OBJECT (item));
double sign = (goc_canvas_get_direction (item->canvas) == GOC_DIRECTION_RTL)? -1: 1;
double endx = (line->endx - line->startx) * sign, endy = line->endy - line->starty;
double hoffs, voffs = ceil (style->line.width);
double startx = 0, starty = 0;
double phi;
if (line->startx == line->endx && line->starty == line->endy)
return;
if (voffs <= 0.)
voffs = 1.;
hoffs = ((int) voffs & 1)? .5: 0.;
voffs = (line->starty == line->endy)? hoffs: 0.;
if (line->startx != line->endx)
hoffs = 0.;
cairo_save (cr);
_goc_item_transform (item, cr, TRUE);
goc_group_cairo_transform (item->parent, cr,
hoffs + floor (line->startx),
voffs + floor (line->starty));
endx = (endx > 0.)? ceil (endx): floor (endx);
endy = (endy > 0.)? ceil (endy): floor (endy);
phi = atan2 (endy, endx);
draw_arrow (&line->start_arrow, cr, style,
&startx, &starty, phi + M_PI);
draw_arrow (&line->end_arrow, cr, style,
&endx, &endy, phi);
if ((endx != 0. || endy!= 0.) &&
go_styled_object_set_cairo_line (GO_STYLED_OBJECT (item), cr)) {
/* try to avoid horizontal and vertical lines between two pixels */
cairo_move_to (cr, startx, starty);
cairo_line_to (cr, endx, endy);
cairo_stroke (cr);
}
cairo_restore (cr);
}
static void
goc_line_set_property (GObject *gobject, guint param_id,
GValue const *value, GParamSpec *pspec)
{
GocLine *line = GOC_LINE (gobject);
switch (param_id) {
case LINE_PROP_X0:
line->startx = g_value_get_double (value);
break;
case LINE_PROP_Y0:
line->starty = g_value_get_double (value);
break;
case LINE_PROP_X1:
line->endx = g_value_get_double (value);
break;
case LINE_PROP_Y1:
line->endy = g_value_get_double (value);
break;
case LINE_PROP_START_ARROW:
line->start_arrow = *((GOArrow *)g_value_peek_pointer (value));
break;
case LINE_PROP_END_ARROW:
line->end_arrow = *((GOArrow *)g_value_peek_pointer (value));
break;
default: G_OBJECT_WARN_INVALID_PROPERTY_ID (gobject, param_id, pspec);
return; /* NOTE : RETURN */
}
goc_item_bounds_changed (GOC_ITEM (gobject));
}
static double
goc_line_distance (GocItem *item, double x, double y, GocItem **near_item)
{
GocLine *line = GOC_LINE (item);
double dx, dy, l, t;
GOStyle *style;
dx = line->endx - line->startx;
dy = line->endy - line->starty;
l = hypot (dx, dy);
x -= line->startx;
y -= line->starty;
t = (x * dx + y * dy) / l;
y = (-x * dy + y * dx) / l;
*near_item = item;
if (t < 0.)
return hypot (t, y); /* that might be not fully exact,
but we don't need a large precision */
if (t > l)
return hypot (t - l, y);
style = go_styled_object_get_style (GO_STYLED_OBJECT (item));
t = fabs (y) - ((style->line.width > 5)? style->line.width/ 2.: 2.5);
/* FIXME: do we need to take the arrow end into account? */
return (t > 0.)? t: 0.;
}
