canvas-text.cpp revision d30d92cb3986f498497418917e65f061073f81f8
#define __SP_CANVASTEXT_C__
/*
* Canvas text
*
* Authors:
* Lauris Kaplinski <lauris@kaplinski.com>
* Maximilian Albert <maximilian.albert@gmail.com>
*
* Copyright (C) 2000-2002 Lauris Kaplinski
* Copyright (C) 2008 Maximilian Albert
*
* Released under GNU GPL, read the file 'COPYING' for more information
*/
#ifdef HAVE_CONFIG_H
# include "config.h"
#endif
#include <sstream>
#include <string.h>
#include "display-forward.h"
#include "sp-canvas-util.h"
#include "canvas-text.h"
#include "display/cairo-utils.h"
#include "desktop.h"
#include "color.h"
static void sp_canvastext_class_init (SPCanvasTextClass *klass);
static void sp_canvastext_init (SPCanvasText *canvastext);
static void sp_canvastext_destroy (GtkObject *object);
static void sp_canvastext_update (SPCanvasItem *item, Geom::Affine const &affine, unsigned int flags);
static void sp_canvastext_render (SPCanvasItem *item, SPCanvasBuf *buf);
static SPCanvasItemClass *parent_class_ct;
GtkType
sp_canvastext_get_type (void)
{
static GtkType type = 0;
if (!type) {
GtkTypeInfo info = {
(gchar *)"SPCanvasText",
sizeof (SPCanvasText),
sizeof (SPCanvasTextClass),
(GtkClassInitFunc) sp_canvastext_class_init,
(GtkObjectInitFunc) sp_canvastext_init,
NULL, NULL, NULL
};
type = gtk_type_unique (SP_TYPE_CANVAS_ITEM, &info);
}
return type;
}
static void
sp_canvastext_class_init (SPCanvasTextClass *klass)
{
GtkObjectClass *object_class = (GtkObjectClass *) klass;
SPCanvasItemClass *item_class = (SPCanvasItemClass *) klass;
parent_class_ct = (SPCanvasItemClass*)gtk_type_class (SP_TYPE_CANVAS_ITEM);
object_class->destroy = sp_canvastext_destroy;
item_class->update = sp_canvastext_update;
item_class->render = sp_canvastext_render;
}
static void
sp_canvastext_init (SPCanvasText *canvastext)
{
canvastext->rgba = 0x33337fff;
canvastext->rgba_stroke = 0xffffffff;
canvastext->rgba_background = 0x0000007f;
canvastext->background = false;
canvastext->s[Geom::X] = canvastext->s[Geom::Y] = 0.0;
canvastext->affine = Geom::identity();
canvastext->fontsize = 10.0;
canvastext->item = NULL;
canvastext->desktop = NULL;
canvastext->text = NULL;
}
static void
sp_canvastext_destroy (GtkObject *object)
{
g_return_if_fail (object != NULL);
g_return_if_fail (SP_IS_CANVASTEXT (object));
SPCanvasText *canvastext = SP_CANVASTEXT (object);
g_free(canvastext->text);
canvastext->text = NULL;
canvastext->item = NULL;
if (GTK_OBJECT_CLASS (parent_class_ct)->destroy)
(* GTK_OBJECT_CLASS (parent_class_ct)->destroy) (object);
}
// FIXME: remove this as soon as we know how to correctly determine the text extent
static const double arbitrary_factor = 0.8;
// these are set in sp_canvastext_update() and then re-used in sp_canvastext_render(), which is called afterwards
static double anchor_offset_x = 0;
static double anchor_offset_y = 0;
static void
sp_canvastext_render (SPCanvasItem *item, SPCanvasBuf *buf)
{
SPCanvasText *cl = SP_CANVASTEXT (item);
if (!buf->ct)
return;
Geom::Point s = cl->s * cl->affine;
double offsetx = s[Geom::X] - buf->rect.x0;
double offsety = s[Geom::Y] - buf->rect.y0;
offsetx -= anchor_offset_x;
offsety += anchor_offset_y;
if (cl->background){
cairo_text_extents_t extents;
cairo_text_extents(buf->ct, cl->text, &extents);
double border = extents.height*0.5;
cairo_rectangle(buf->ct, offsetx - extents.x_bearing - border,
offsety + extents.y_bearing - border,
extents.width + 2*border,
extents.height + 2*border);
ink_cairo_set_source_rgba32(buf->ct, cl->rgba_background);
cairo_fill(buf->ct);
}
cairo_move_to(buf->ct, offsetx, offsety);
cairo_set_font_size(buf->ct, cl->fontsize);
cairo_text_path(buf->ct, cl->text);
if (cl->outline){
ink_cairo_set_source_rgba32(buf->ct, cl->rgba_stroke);
cairo_set_line_width (buf->ct, 2.0);
cairo_stroke_preserve(buf->ct);
}
ink_cairo_set_source_rgba32(buf->ct, cl->rgba);
cairo_fill(buf->ct);
}
static void
sp_canvastext_update (SPCanvasItem *item, Geom::Affine const &affine, unsigned int flags)
{
SPCanvasText *cl = SP_CANVASTEXT (item);
sp_canvas_request_redraw (item->canvas, (int)item->x1, (int)item->y1, (int)item->x2, (int)item->y2);
if (parent_class_ct->update)
(* parent_class_ct->update) (item, affine, flags);
sp_canvas_item_reset_bounds (item);
cl->affine = affine;
Geom::Point s = cl->s * affine;
// set up a temporary cairo_t to measure the text extents; it would be better to compute this in the render()
// method but update() seems to be called before so we don't have the information available when we need it
cairo_surface_t *tmp_surface = cairo_image_surface_create(CAIRO_FORMAT_ARGB32, 1, 1);
cairo_t* tmp_buf = cairo_create(tmp_surface);
cairo_text_extents_t extents;
cairo_text_extents(tmp_buf, cl->text, &extents);
double border = extents.height*1.5;
item->x1 = s[Geom::X] - extents.x_bearing - border;
item->y1 = s[Geom::Y] + extents.y_bearing - border;
item->x2 = s[Geom::X] + extents.width + border;
item->y2 = s[Geom::Y] + extents.height + border;
// adjust update region according to anchor shift
// FIXME: use the correct text extent
anchor_offset_x = arbitrary_factor * cl->fontsize * strlen(cl->text) * (cl->anchor_x + 1.0) / 2.0;
anchor_offset_y = cl->fontsize * (cl->anchor_y + 1.0) / 2.0;
item->x1 -= anchor_offset_x;
item->x2 -= anchor_offset_x;
item->y1 += anchor_offset_y;
item->y2 += anchor_offset_y;
sp_canvas_request_redraw (item->canvas, (int)item->x1, (int)item->y1, (int)item->x2, (int)item->y2);
}
SPCanvasItem *
sp_canvastext_new(SPCanvasGroup *parent, SPDesktop *desktop, Geom::Point pos, gchar const *new_text)
{
SPCanvasItem *item = sp_canvas_item_new(parent, SP_TYPE_CANVASTEXT, NULL);
SPCanvasText *ct = SP_CANVASTEXT(item);
ct->desktop = desktop;
ct->s = pos;
g_free(ct->text);
ct->text = g_strdup(new_text);
// TODO: anything else to do?
return item;
}
void
sp_canvastext_set_rgba32 (SPCanvasText *ct, guint32 rgba, guint32 rgba_stroke)
{
g_return_if_fail (ct != NULL);
g_return_if_fail (SP_IS_CANVASTEXT (ct));
if (rgba != ct->rgba || rgba_stroke != ct->rgba_stroke) {
ct->rgba = rgba;
ct->rgba_stroke = rgba_stroke;
SPCanvasItem *item = SP_CANVAS_ITEM (ct);
sp_canvas_item_request_update( item );
}
}
#define EPSILON 1e-6
#define DIFFER(a,b) (fabs ((a) - (b)) > EPSILON)
void
sp_canvastext_set_coords (SPCanvasText *ct, gdouble x0, gdouble y0)
{
sp_canvastext_set_coords(ct, Geom::Point(x0, y0));
}
void
sp_canvastext_set_coords (SPCanvasText *ct, const Geom::Point start)
{
Geom::Point pos = ct->desktop->doc2dt(start);
g_return_if_fail (ct != NULL);
g_return_if_fail (SP_IS_CANVASTEXT (ct));
if (DIFFER (pos[0], ct->s[Geom::X]) || DIFFER (pos[1], ct->s[Geom::Y])) {
ct->s[Geom::X] = pos[0];
ct->s[Geom::Y] = pos[1];
sp_canvas_item_request_update (SP_CANVAS_ITEM (ct));
}
}
void
sp_canvastext_set_text (SPCanvasText *ct, gchar const * new_text)
{
g_free (ct->text);
ct->text = g_strdup(new_text);
sp_canvas_item_request_update (SP_CANVAS_ITEM (ct));
}
void
sp_canvastext_set_number_as_text (SPCanvasText *ct, int num)
{
std::ostringstream number;
number << num;
sp_canvastext_set_text(ct, number.str().c_str());
}
void
sp_canvastext_set_fontsize (SPCanvasText *ct, double size)
{
ct->fontsize = size;
}
void
sp_canvastext_set_anchor (SPCanvasText *ct, double anchor_x, double anchor_y)
{
ct->anchor_x = anchor_x;
ct->anchor_y = anchor_y;
}
/*
Local Variables:
mode:c++
c-file-style:"stroustrup"
c-file-offsets:((innamespace . 0)(inline-open . 0)(case-label . +))
indent-tabs-mode:nil
fill-column:99
End:
*/
// vim: filetype=cpp:expandtab:shiftwidth=4:tabstop=8:softtabstop=4:fileencoding=utf-8:textwidth=99 :