#define GNOME_CANVAS_CLIPGROUP_C
/* Clipping group for GnomeCanvas
*
* 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.
*
* Copyright (C) 1998,1999 The Free Software Foundation
*
* Author:
* Lauris Kaplinski <lauris@ximian.com>
*/
/* These includes are set up for standalone compile. If/when this codebase
is integrated into libgnomeui, the includes will need to change. */
#include <math.h>
#include <string.h>
#include <gtk/gtk.h>
#include <libart_lgpl/art_misc.h>
#include <libart_lgpl/art_rect.h>
#include <libart_lgpl/art_vpath.h>
#include <libart_lgpl/art_bpath.h>
#include <libart_lgpl/art_vpath.h>
#include <libart_lgpl/art_vpath_bpath.h>
#include <libart_lgpl/art_svp.h>
#include <libart_lgpl/art_svp_vpath.h>
#include <libart_lgpl/art_rect_svp.h>
#include <libart_lgpl/art_gray_svp.h>
#include <libart_lgpl/art_svp_intersect.h>
#include <libart_lgpl/art_svp_ops.h>
#include "gnome-canvas.h"
#include "gnome-canvas-util.h"
#include "gnome-canvas-clipgroup.h"
enum {
PROP_0,
PROP_PATH,
PROP_WIND
};
static void gnome_canvas_clipgroup_class_init (GnomeCanvasClipgroupClass *klass);
static void gnome_canvas_clipgroup_init (GnomeCanvasClipgroup *clipgroup);
static void gnome_canvas_clipgroup_destroy (GtkObject *object);
static void gnome_canvas_clipgroup_set_property (GObject *object,
guint param_id,
const GValue *value,
GParamSpec *pspec);
static void gnome_canvas_clipgroup_get_property (GObject *object,
guint param_id,
GValue *value,
GParamSpec *pspec);
static void gnome_canvas_clipgroup_update (GnomeCanvasItem *item,
gdouble *affine,
ArtSVP *clip_path,
gint flags);
/*
* Generic clipping stuff
*
* This is somewhat slow and memory-hungry - we add extra
* composition, extra SVP render and allocate 65536
* bytes for each clip level. It could be done more
* efficently per-object basis - but to make clipping
* universal, there is no alternative to double
* buffering (although it should be done into RGBA
* buffer by other method than ::render to make global
* opacity possible).
* Using art-render could possibly optimize that a bit,
* although I am not sure.
*/
#define GCG_BUF_WIDTH 128
#define GCG_BUF_HEIGHT 128
#define GCG_BUF_PIXELS (GCG_BUF_WIDTH * GCG_BUF_HEIGHT)
#define GCG_BUF_SIZE (GCG_BUF_WIDTH * GCG_BUF_HEIGHT * 3)
#define noSHOW_SHADOW
static guchar *gcg_buf_new (void);
static void gcg_buf_free (guchar *buf);
static guchar *gcg_mask_new (void);
static void gcg_mask_free (guchar *mask);
static void gnome_canvas_clipgroup_render (GnomeCanvasItem *item, GnomeCanvasBuf *buf);
static GnomeCanvasGroupClass *parent_class;
GType
gnome_canvas_clipgroup_get_type (void)
{
static GType clipgroup_type;
if (!clipgroup_type) {
const GTypeInfo object_info = {
sizeof (GnomeCanvasClipgroupClass),
(GBaseInitFunc) NULL,
(GBaseFinalizeFunc) NULL,
(GClassInitFunc) gnome_canvas_clipgroup_class_init,
(GClassFinalizeFunc) NULL,
NULL, /* class_data */
sizeof (GnomeCanvasClipgroup),
0, /* n_preallocs */
(GInstanceInitFunc) gnome_canvas_clipgroup_init,
NULL /* value_table */
};
clipgroup_type = g_type_register_static (GNOME_TYPE_CANVAS_GROUP, "GnomeCanvasClipgroup",
&object_info, 0);
}
return clipgroup_type;
}
static void
gnome_canvas_clipgroup_class_init (GnomeCanvasClipgroupClass *klass)
{
GObjectClass *gobject_class;
GtkObjectClass *object_class;
GnomeCanvasItemClass *item_class;
gobject_class = (GObjectClass *) klass;
object_class = (GtkObjectClass *) klass;
item_class = (GnomeCanvasItemClass *) klass;
parent_class = g_type_class_ref (GNOME_TYPE_CANVAS_GROUP);
object_class->destroy = gnome_canvas_clipgroup_destroy;
gobject_class->set_property = gnome_canvas_clipgroup_set_property;
gobject_class->get_property = gnome_canvas_clipgroup_get_property;
item_class->update = gnome_canvas_clipgroup_update;
item_class->render = gnome_canvas_clipgroup_render;
g_object_class_install_property (gobject_class,
PROP_PATH,
g_param_spec_pointer ("path", NULL, NULL,
(G_PARAM_READABLE | G_PARAM_WRITABLE)));
g_object_class_install_property (gobject_class,
PROP_WIND,
g_param_spec_uint ("wind", NULL, NULL,
0, G_MAXUINT, 0,
(G_PARAM_READABLE | G_PARAM_WRITABLE)));
}
static void
gnome_canvas_clipgroup_init (GnomeCanvasClipgroup *clipgroup)
{
clipgroup->path = NULL;
clipgroup->wind = ART_WIND_RULE_NONZERO; /* default winding rule */
clipgroup->svp = NULL;
}
static void
gnome_canvas_clipgroup_destroy (GtkObject *object)
{
GnomeCanvasClipgroup *clipgroup;
g_return_if_fail (object != NULL);
g_return_if_fail (GNOME_IS_CANVAS_CLIPGROUP (object));
clipgroup = GNOME_CANVAS_CLIPGROUP (object);
if (clipgroup->path) {
gnome_canvas_path_def_unref (clipgroup->path);
clipgroup->path = NULL;
}
if (clipgroup->svp) {
art_svp_free (clipgroup->svp);
clipgroup->svp = NULL;
}
if (GTK_OBJECT_CLASS (parent_class)->destroy)
(* GTK_OBJECT_CLASS (parent_class)->destroy) (object);
}
static void
gnome_canvas_clipgroup_set_property (GObject *object,
guint param_id,
const GValue *value,
GParamSpec *pspec)
{
GnomeCanvasItem *item;
GnomeCanvasClipgroup *cgroup;
GnomeCanvasPathDef *gpp;
item = GNOME_CANVAS_ITEM (object);
cgroup = GNOME_CANVAS_CLIPGROUP (object);
switch (param_id) {
case PROP_PATH:
gpp = g_value_get_pointer (value);
if (cgroup->path) {
gnome_canvas_path_def_unref (cgroup->path);
cgroup->path = NULL;
}
if (gpp != NULL) {
cgroup->path = gnome_canvas_path_def_closed_parts (gpp);
}
gnome_canvas_item_request_update (item);
break;
case PROP_WIND:
cgroup->wind = g_value_get_uint (value);
gnome_canvas_item_request_update (item);
break;
default:
break;
}
}
static void
gnome_canvas_clipgroup_get_property (GObject *object,
guint param_id,
GValue *value,
GParamSpec *pspec)
{
GnomeCanvasClipgroup * cgroup;
cgroup = GNOME_CANVAS_CLIPGROUP (object);
switch (param_id) {
case PROP_PATH:
g_value_set_pointer (value, cgroup->path);
break;
case PROP_WIND:
g_value_set_uint (value, cgroup->wind);
break;
default:
G_OBJECT_WARN_INVALID_PROPERTY_ID (object, param_id, pspec);
break;
}
}
static void
gnome_canvas_clipgroup_update (GnomeCanvasItem *item, gdouble *affine, ArtSVP *clip_path, gint flags)
{
GnomeCanvasClipgroup *clipgroup;
ArtSvpWriter *swr;
ArtBpath *bp;
ArtBpath *bpath;
ArtVpath *vpath;
ArtSVP *svp, *svp1, *svp2;
clipgroup = GNOME_CANVAS_CLIPGROUP (item);
if (clipgroup->svp) {
art_svp_free (clipgroup->svp);
clipgroup->svp = NULL;
}
if (clipgroup->path) {
bp = gnome_canvas_path_def_bpath (clipgroup->path);
bpath = art_bpath_affine_transform (bp, affine);
vpath = art_bez_path_to_vec (bpath, 0.25);
art_free (bpath);
svp1 = art_svp_from_vpath (vpath);
art_free (vpath);
swr = art_svp_writer_rewind_new (clipgroup->wind);
art_svp_intersector (svp1, swr);
svp2 = art_svp_writer_rewind_reap (swr);
art_svp_free (svp1);
if (clip_path != NULL) {
svp = art_svp_intersect (svp2, clip_path);
art_svp_free (svp2);
} else {
svp = svp2;
}
clipgroup->svp = svp;
}
if (GNOME_CANVAS_ITEM_CLASS (parent_class)->update)
(GNOME_CANVAS_ITEM_CLASS (parent_class)->update) (item, affine, NULL, flags);
if (clipgroup->svp) {
ArtDRect cbox;
art_drect_svp (&cbox, clipgroup->svp);
item->x1 = MAX (item->x1, cbox.x0 - 1.0);
item->y1 = MAX (item->y1, cbox.y0 - 1.0);
item->x2 = MIN (item->x2, cbox.x1 + 1.0);
item->y2 = MIN (item->y2, cbox.y1 + 1.0);
}
}
/* non-premultiplied composition into RGB */
#define COMPOSEN11(fc,fa,bc) (((255 - (guint) (fa)) * (guint) (bc) + (guint) (fc) * (guint) (fa) + 127) / 255)
static void
gnome_canvas_clipgroup_render (GnomeCanvasItem *item, GnomeCanvasBuf *buf)
{
GnomeCanvasClipgroup *cg;
GnomeCanvasBuf lbuf;
guchar *mask;
cg = GNOME_CANVAS_CLIPGROUP (item);
if (cg->svp) {
gint bw, bh, sw, sh;
gint x, y;
/* fixme: We could optimize background handling (lauris) */
if (buf->is_bg) {
gnome_canvas_buf_ensure_buf (buf);
buf->is_bg = FALSE;
buf->is_buf = TRUE;
}
bw = buf->rect.x1 - buf->rect.x0;
bh = buf->rect.y1 - buf->rect.y0;
if ((bw < 1) || (bh < 1)) return;
if (bw * bh <= GCG_BUF_PIXELS) {
/* We can go with single buffer */
sw = bw;
sh = bh;
} else if (bw <= (GCG_BUF_PIXELS >> 3)) {
/* Go with row buffer */
sw = bw;
sh = GCG_BUF_PIXELS / bw;
} else if (bh <= (GCG_BUF_PIXELS >> 3)) {
/* Go with column buffer */
sw = GCG_BUF_PIXELS / bh;
sh = bh;
} else {
/* Tile buffer */
sw = GCG_BUF_WIDTH;
sh = GCG_BUF_HEIGHT;
}
/* Set up local buffer */
lbuf.buf = gcg_buf_new ();
lbuf.bg_color = buf->bg_color;
lbuf.is_bg = FALSE;
lbuf.is_buf = TRUE;
/* Allocate mask */
mask = gcg_mask_new ();
for (y = buf->rect.y0; y < buf->rect.y1; y += sh) {
for (x = buf->rect.x0; x < buf->rect.x1; x += sw) {
gint r, xx, yy;
/* Set up local buffer */
lbuf.rect.x0 = x;
lbuf.rect.y0 = y;
lbuf.rect.x1 = MIN (x + sw, buf->rect.x1);
lbuf.rect.y1 = MIN (y + sh, buf->rect.y1);
lbuf.buf_rowstride = 3 * (lbuf.rect.x1 - lbuf.rect.x0);
/* Copy background */
for (r = lbuf.rect.y0; r < lbuf.rect.y1; r++) {
memcpy (lbuf.buf + (r - lbuf.rect.y0) * lbuf.buf_rowstride,
buf->buf + (r - buf->rect.y0) * buf->buf_rowstride + (x - buf->rect.x0) * 3,
(lbuf.rect.x1 - lbuf.rect.x0) * 3);
}
/* Invoke render method */
if (((GnomeCanvasItemClass *) parent_class)->render)
((GnomeCanvasItemClass *) parent_class)->render (item, &lbuf);
/* Render mask */
art_gray_svp_aa (cg->svp, lbuf.rect.x0, lbuf.rect.y0, lbuf.rect.x1, lbuf.rect.y1,
mask, lbuf.rect.x1 - lbuf.rect.x0);
/* Combine */
for (yy = lbuf.rect.y0; yy < lbuf.rect.y1; yy++) {
guchar *s, *m, *d;
s = lbuf.buf + (yy - lbuf.rect.y0) * lbuf.buf_rowstride;
m = mask + (yy - lbuf.rect.y0) * (lbuf.rect.x1 - lbuf.rect.x0);
d = buf->buf + (yy - buf->rect.y0) * buf->buf_rowstride + (x - buf->rect.x0) * 3;
for (xx = lbuf.rect.x0; xx < lbuf.rect.x1; xx++) {
#ifndef SHOW_SHADOW
d[0] = COMPOSEN11 (s[0], m[0], d[0]);
d[1] = COMPOSEN11 (s[1], m[0], d[1]);
d[2] = COMPOSEN11 (s[2], m[0], d[2]);
#else
d[0] = COMPOSEN11 (s[0], m[0] | 0x7f, d[0]);
d[1] = COMPOSEN11 (s[1], m[0] | 0x7f, d[1]);
d[2] = COMPOSEN11 (s[2], m[0] | 0x7f, d[2]);
#endif
s += 3;
m += 1;
d += 3;
}
}
}
}
/* Free buffers */
gcg_mask_free (mask);
gcg_buf_free (lbuf.buf);
} else {
if (((GnomeCanvasItemClass *) parent_class)->render)
((GnomeCanvasItemClass *) parent_class)->render (item, buf);
}
}
static GSList *gcg_buffers = NULL;
static GSList *gcg_masks = NULL;
static guchar *
gcg_buf_new (void)
{
guchar *buf;
if (!gcg_buffers) {
buf = g_new (guchar, GCG_BUF_SIZE);
} else {
buf = (guchar *) gcg_buffers->data;
gcg_buffers = g_slist_remove (gcg_buffers, buf);
}
return buf;
}
static void
gcg_buf_free (guchar *buf)
{
gcg_buffers = g_slist_prepend (gcg_buffers, buf);
}
static guchar *
gcg_mask_new (void)
{
guchar *mask;
if (!gcg_masks) {
mask = g_new (guchar, GCG_BUF_PIXELS);
} else {
mask = (guchar *) gcg_masks->data;
gcg_masks = g_slist_remove (gcg_masks, mask);
}
return mask;
}
static void
gcg_mask_free (guchar *mask)
{
gcg_masks = g_slist_prepend (gcg_masks, mask);
}
