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gnome-canvas-clipgroup.c @ 20821

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Revision 20821, 12.6 KB checked in by ghudson, 20 years ago (diff)
This commit was generated by cvs2svn to compensate for changes in r20820, which included commits to RCS files with non-trunk default branches.

Line
1	#define GNOME_CANVAS_CLIPGROUP_C
2
3	/* Clipping group for GnomeCanvas
4	*
5	* GnomeCanvas is basically a port of the Tk toolkit's most excellent canvas widget. Tk is
6	* copyrighted by the Regents of the University of California, Sun Microsystems, and other parties.
7	*
8	* Copyright (C) 1998,1999 The Free Software Foundation
9	*
10	* Author:
11	* Lauris Kaplinski <lauris@ximian.com>
12	*/
13
14	/* These includes are set up for standalone compile. If/when this codebase
15	is integrated into libgnomeui, the includes will need to change. */
16
17	#include <math.h>
18	#include <string.h>
19
20	#include <gtk/gtkobject.h>
21	#include <gtk/gtkwidget.h>
22
23	#include <libart_lgpl/art_misc.h>
24	#include <libart_lgpl/art_rect.h>
25	#include <libart_lgpl/art_vpath.h>
26	#include <libart_lgpl/art_bpath.h>
27	#include <libart_lgpl/art_vpath.h>
28	#include <libart_lgpl/art_vpath_bpath.h>
29	#include <libart_lgpl/art_svp.h>
30	#include <libart_lgpl/art_svp_vpath.h>
31	#include <libart_lgpl/art_rect_svp.h>
32	#include <libart_lgpl/art_gray_svp.h>
33	#include <libart_lgpl/art_svp_intersect.h>
34	#include <libart_lgpl/art_svp_ops.h>
35
36	#include "gnome-canvas.h"
37	#include "gnome-canvas-util.h"
38	#include "gnome-canvas-clipgroup.h"
39
40	enum {
41	PROP_0,
42	PROP_PATH,
43	PROP_WIND
44	};
45
46	static void gnome_canvas_clipgroup_class_init (GnomeCanvasClipgroupClass *klass);
47	static void gnome_canvas_clipgroup_init (GnomeCanvasClipgroup *clipgroup);
48	static void gnome_canvas_clipgroup_destroy (GtkObject *object);
49	static void gnome_canvas_clipgroup_set_property (GObject *object,
50	guint param_id,
51	const GValue *value,
52	GParamSpec *pspec);
53	static void gnome_canvas_clipgroup_get_property (GObject *object,
54	guint param_id,
55	GValue *value,
56	GParamSpec *pspec);
57	static void gnome_canvas_clipgroup_update (GnomeCanvasItem *item,
58	double *affine,
59	ArtSVP *clip_path,
60	int flags);
61
62	/*
63	* Generic clipping stuff
64	*
65	* This is somewhat slow and memory-hungry - we add extra
66	* composition, extra SVP render and allocate 65536
67	* bytes for each clip level. It could be done more
68	* efficently per-object basis - but to make clipping
69	* universal, there is no alternative to double
70	* buffering (although it should be done into RGBA
71	* buffer by other method than ::render to make global
72	* opacity possible).
73	* Using art-render could possibly optimize that a bit,
74	* although I am not sure.
75	*/
76
77	#define GCG_BUF_WIDTH 128
78	#define GCG_BUF_HEIGHT 128
79	#define GCG_BUF_PIXELS (GCG_BUF_WIDTH * GCG_BUF_HEIGHT)
80	#define GCG_BUF_SIZE (GCG_BUF_WIDTH * GCG_BUF_HEIGHT * 3)
81
82	#define noSHOW_SHADOW
83
84	static guchar *gcg_buf_new (void);
85	static void gcg_buf_free (guchar *buf);
86	static guchar *gcg_mask_new (void);
87	static void gcg_mask_free (guchar *mask);
88
89	static void gnome_canvas_clipgroup_render (GnomeCanvasItem item, GnomeCanvasBuf buf);
90
91	static GnomeCanvasGroupClass *parent_class;
92
93	GType
94	gnome_canvas_clipgroup_get_type (void)
95	{
96	static GType clipgroup_type;
97
98	if (!clipgroup_type) {
99	static const GTypeInfo object_info = {
100	sizeof (GnomeCanvasClipgroupClass),
101	(GBaseInitFunc) NULL,
102	(GBaseFinalizeFunc) NULL,
103	(GClassInitFunc) gnome_canvas_clipgroup_class_init,
104	(GClassFinalizeFunc) NULL,
105	NULL, /* class_data */
106	sizeof (GnomeCanvasClipgroup),
107	0, /* n_preallocs */
108	(GInstanceInitFunc) gnome_canvas_clipgroup_init,
109	NULL /* value_table */
110	};
111
112	clipgroup_type = g_type_register_static (GNOME_TYPE_CANVAS_GROUP, "GnomeCanvasClipgroup",
113	&object_info, 0);
114	}
115
116	return clipgroup_type;
117	}
118
119	static void
120	gnome_canvas_clipgroup_class_init (GnomeCanvasClipgroupClass *klass)
121	{
122	GObjectClass *gobject_class;
123	GtkObjectClass *object_class;
124	GnomeCanvasItemClass *item_class;
125
126	gobject_class = (GObjectClass *) klass;
127	object_class = (GtkObjectClass *) klass;
128	item_class = (GnomeCanvasItemClass *) klass;
129	parent_class = g_type_class_ref (GNOME_TYPE_CANVAS_GROUP);
130
131	object_class->destroy = gnome_canvas_clipgroup_destroy;
132	gobject_class->set_property = gnome_canvas_clipgroup_set_property;
133	gobject_class->get_property = gnome_canvas_clipgroup_get_property;
134	item_class->update = gnome_canvas_clipgroup_update;
135	item_class->render = gnome_canvas_clipgroup_render;
136
137	g_object_class_install_property (gobject_class,
138	PROP_PATH,
139	g_param_spec_pointer ("path", NULL, NULL,
140	(G_PARAM_READABLE \| G_PARAM_WRITABLE)));
141	g_object_class_install_property (gobject_class,
142	PROP_WIND,
143	g_param_spec_uint ("wind", NULL, NULL,
144	0, G_MAXUINT, 0,
145	(G_PARAM_READABLE \| G_PARAM_WRITABLE)));
146	}
147
148	static void
149	gnome_canvas_clipgroup_init (GnomeCanvasClipgroup *clipgroup)
150	{
151	clipgroup->path = NULL;
152	clipgroup->wind = ART_WIND_RULE_NONZERO; /* default winding rule */
153	clipgroup->svp = NULL;
154	}
155
156	static void
157	gnome_canvas_clipgroup_destroy (GtkObject *object)
158	{
159	GnomeCanvasClipgroup *clipgroup;
160
161	g_return_if_fail (object != NULL);
162	g_return_if_fail (GNOME_IS_CANVAS_CLIPGROUP (object));
163
164	clipgroup = GNOME_CANVAS_CLIPGROUP (object);
165
166	if (clipgroup->path) {
167	gnome_canvas_path_def_unref (clipgroup->path);
168	clipgroup->path = NULL;
169	}
170
171	if (clipgroup->svp) {
172	art_svp_free (clipgroup->svp);
173	clipgroup->svp = NULL;
174	}
175
176	if (GTK_OBJECT_CLASS (parent_class)->destroy)
177	(* GTK_OBJECT_CLASS (parent_class)->destroy) (object);
178	}
179
180
181	static void
182	gnome_canvas_clipgroup_set_property (GObject *object,
183	guint param_id,
184	const GValue *value,
185	GParamSpec *pspec)
186	{
187	GnomeCanvasItem *item;
188	GnomeCanvasClipgroup *cgroup;
189	GnomeCanvasPathDef *gpp;
190
191	item = GNOME_CANVAS_ITEM (object);
192	cgroup = GNOME_CANVAS_CLIPGROUP (object);
193
194	switch (param_id) {
195	case PROP_PATH:
196	gpp = g_value_get_pointer (value);
197
198	if (cgroup->path) {
199	gnome_canvas_path_def_unref (cgroup->path);
200	cgroup->path = NULL;
201	}
202	if (gpp != NULL) {
203	cgroup->path = gnome_canvas_path_def_closed_parts (gpp);
204	}
205
206	gnome_canvas_item_request_update (item);
207	break;
208
209	case PROP_WIND:
210	cgroup->wind = g_value_get_uint (value);
211	gnome_canvas_item_request_update (item);
212	break;
213
214	default:
215	break;
216	}
217	}
218
219	static void
220	gnome_canvas_clipgroup_get_property (GObject *object,
221	guint param_id,
222	GValue *value,
223	GParamSpec *pspec)
224	{
225	GnomeCanvasClipgroup * cgroup;
226
227	cgroup = GNOME_CANVAS_CLIPGROUP (object);
228
229	switch (param_id) {
230	case PROP_PATH:
231	g_value_set_pointer (value, cgroup->path);
232	break;
233
234	case PROP_WIND:
235	g_value_set_uint (value, cgroup->wind);
236	break;
237
238	default:
239	G_OBJECT_WARN_INVALID_PROPERTY_ID (object, param_id, pspec);
240	break;
241	}
242	}
243
244	static void
245	gnome_canvas_clipgroup_update (GnomeCanvasItem item, double affine, ArtSVP *clip_path, int flags)
246	{
247	GnomeCanvasClipgroup *clipgroup;
248	ArtSvpWriter *swr;
249	ArtBpath *bp;
250	ArtBpath *bpath;
251	ArtVpath *vpath;
252	ArtSVP svp, svp1, *svp2;
253
254	clipgroup = GNOME_CANVAS_CLIPGROUP (item);
255
256	if (clipgroup->svp) {
257	art_svp_free (clipgroup->svp);
258	clipgroup->svp = NULL;
259	}
260
261	if (clipgroup->path) {
262	bp = gnome_canvas_path_def_bpath (clipgroup->path);
263	bpath = art_bpath_affine_transform (bp, affine);
264
265	vpath = art_bez_path_to_vec (bpath, 0.25);
266	art_free (bpath);
267
268	svp1 = art_svp_from_vpath (vpath);
269	art_free (vpath);
270
271	swr = art_svp_writer_rewind_new (clipgroup->wind);
272	art_svp_intersector (svp1, swr);
273
274	svp2 = art_svp_writer_rewind_reap (swr);
275	art_svp_free (svp1);
276
277	if (clip_path != NULL) {
278	svp = art_svp_intersect (svp2, clip_path);
279	art_svp_free (svp2);
280	} else {
281	svp = svp2;
282	}
283
284	clipgroup->svp = svp;
285	}
286
287	if (GNOME_CANVAS_ITEM_CLASS (parent_class)->update)
288	(GNOME_CANVAS_ITEM_CLASS (parent_class)->update) (item, affine, NULL, flags);
289
290	if (clipgroup->svp) {
291	ArtDRect cbox;
292	art_drect_svp (&cbox, clipgroup->svp);
293	item->x1 = MAX (item->x1, cbox.x0 - 1.0);
294	item->y1 = MAX (item->y1, cbox.y0 - 1.0);
295	item->x2 = MIN (item->x2, cbox.x1 + 1.0);
296	item->y2 = MIN (item->y2, cbox.y1 + 1.0);
297	}
298	}
299
300	/* non-premultiplied composition into RGB */
301
302	#define COMPOSEN11(fc,fa,bc) (((255 - (guint) (fa)) * (guint) (bc) + (guint) (fc) * (guint) (fa) + 127) / 255)
303
304	static void
305	gnome_canvas_clipgroup_render (GnomeCanvasItem item, GnomeCanvasBuf buf)
306	{
307	GnomeCanvasClipgroup *cg;
308	GnomeCanvasBuf lbuf;
309	guchar *mask;
310
311	cg = GNOME_CANVAS_CLIPGROUP (item);
312
313	if (cg->svp) {
314	gint bw, bh, sw, sh;
315	gint x, y;
316
317	/* fixme: We could optimize background handling (lauris) */
318
319	if (buf->is_bg) {
320	gnome_canvas_buf_ensure_buf (buf);
321	buf->is_bg = FALSE;
322	buf->is_buf = TRUE;
323	}
324
325	bw = buf->rect.x1 - buf->rect.x0;
326	bh = buf->rect.y1 - buf->rect.y0;
327	if ((bw < 1) \|\| (bh < 1)) return;
328
329	if (bw * bh <= GCG_BUF_PIXELS) {
330	/* We can go with single buffer */
331	sw = bw;
332	sh = bh;
333	} else if (bw <= (GCG_BUF_PIXELS >> 3)) {
334	/* Go with row buffer */
335	sw = bw;
336	sh = GCG_BUF_PIXELS / bw;
337	} else if (bh <= (GCG_BUF_PIXELS >> 3)) {
338	/* Go with column buffer */
339	sw = GCG_BUF_PIXELS / bh;
340	sh = bh;
341	} else {
342	/* Tile buffer */
343	sw = GCG_BUF_WIDTH;
344	sh = GCG_BUF_HEIGHT;
345	}
346
347	/* Set up local buffer */
348	lbuf.buf = gcg_buf_new ();
349	lbuf.bg_color = buf->bg_color;
350	lbuf.is_bg = FALSE;
351	lbuf.is_buf = TRUE;
352	/* Allocate mask */
353	mask = gcg_mask_new ();
354
355	for (y = buf->rect.y0; y < buf->rect.y1; y += sh) {
356	for (x = buf->rect.x0; x < buf->rect.x1; x += sw) {
357	gint r, xx, yy;
358	/* Set up local buffer */
359	lbuf.rect.x0 = x;
360	lbuf.rect.y0 = y;
361	lbuf.rect.x1 = MIN (x + sw, buf->rect.x1);
362	lbuf.rect.y1 = MIN (y + sh, buf->rect.y1);
363	lbuf.buf_rowstride = 3 * (lbuf.rect.x1 - lbuf.rect.x0);
364	/* Copy background */
365	for (r = lbuf.rect.y0; r < lbuf.rect.y1; r++) {
366	memcpy (lbuf.buf + (r - lbuf.rect.y0) * lbuf.buf_rowstride,
367	buf->buf + (r - buf->rect.y0) * buf->buf_rowstride + (x - buf->rect.x0) * 3,
368	(lbuf.rect.x1 - lbuf.rect.x0) * 3);
369	}
370	/* Invoke render method */
371	if (((GnomeCanvasItemClass *) parent_class)->render)
372	((GnomeCanvasItemClass *) parent_class)->render (item, &lbuf);
373	/* Render mask */
374	art_gray_svp_aa (cg->svp, lbuf.rect.x0, lbuf.rect.y0, lbuf.rect.x1, lbuf.rect.y1,
375	mask, lbuf.rect.x1 - lbuf.rect.x0);
376	/* Combine */
377	for (yy = lbuf.rect.y0; yy < lbuf.rect.y1; yy++) {
378	guchar s, m, *d;
379	s = lbuf.buf + (yy - lbuf.rect.y0) * lbuf.buf_rowstride;
380	m = mask + (yy - lbuf.rect.y0) * (lbuf.rect.x1 - lbuf.rect.x0);
381	d = buf->buf + (yy - buf->rect.y0) * buf->buf_rowstride + (x - buf->rect.x0) * 3;
382	for (xx = lbuf.rect.x0; xx < lbuf.rect.x1; xx++) {
383	#ifndef SHOW_SHADOW
384	d[0] = COMPOSEN11 (s[0], m[0], d[0]);
385	d[1] = COMPOSEN11 (s[1], m[0], d[1]);
386	d[2] = COMPOSEN11 (s[2], m[0], d[2]);
387	#else
388	d[0] = COMPOSEN11 (s[0], m[0] \| 0x7f, d[0]);
389	d[1] = COMPOSEN11 (s[1], m[0] \| 0x7f, d[1]);
390	d[2] = COMPOSEN11 (s[2], m[0] \| 0x7f, d[2]);
391	#endif
392	s += 3;
393	m += 1;
394	d += 3;
395	}
396	}
397	}
398	}
399	/* Free buffers */
400	gcg_mask_free (mask);
401	gcg_buf_free (lbuf.buf);
402	} else {
403	if (((GnomeCanvasItemClass *) parent_class)->render)
404	((GnomeCanvasItemClass *) parent_class)->render (item, buf);
405	}
406	}
407
408	static GSList *gcg_buffers = NULL;
409	static GSList *gcg_masks = NULL;
410
411	static guchar *
412	gcg_buf_new (void)
413	{
414	guchar *buf;
415
416	if (!gcg_buffers) {
417	buf = g_new (guchar, GCG_BUF_SIZE);
418	} else {
419	buf = (guchar *) gcg_buffers->data;
420	gcg_buffers = g_slist_remove (gcg_buffers, buf);
421	}
422
423	return buf;
424	}
425
426	static void
427	gcg_buf_free (guchar *buf)
428	{
429	gcg_buffers = g_slist_prepend (gcg_buffers, buf);
430	}
431
432	static guchar *
433	gcg_mask_new (void)
434	{
435	guchar *mask;
436
437	if (!gcg_masks) {
438	mask = g_new (guchar, GCG_BUF_PIXELS);
439	} else {
440	mask = (guchar *) gcg_masks->data;
441	gcg_masks = g_slist_remove (gcg_masks, mask);
442	}
443
444	return mask;
445	}
446
447	static void
448	gcg_mask_free (guchar *mask)
449	{
450	gcg_masks = g_slist_prepend (gcg_masks, mask);
451	}

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source: trunk/third/libgnomecanvas/libgnomecanvas/gnome-canvas-clipgroup.c @ 20821

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