src/compositor/svg_text.c

/*
 *			GPAC - Multimedia Framework C SDK
 *
 *			Authors: Cyril Concolato
 *			Copyright (c) Telecom ParisTech 2004-2023
 *					All rights reserved
 *
 *  This file is part of GPAC / Scene Compositor sub-project
 *
 *  GPAC is free software; you can redistribute it and/or modify
 *  it under the terms of the GNU Lesser General Public License as published by
 *  the Free Software Foundation; either version 2, or (at your option)
 *  any later version.
 *
 *  GPAC 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 Lesser General Public License for more details.
 *
 *  You should have received a copy of the GNU Lesser General Public
 *  License along with this library; see the file COPYING.  If not, write to
 *  the Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139, USA.
 *
 */

#include <gpac/utf.h>

#if !defined(GPAC_DISABLE_SVG) &&  !defined(GPAC_DISABLE_COMPOSITOR)

#include "visual_manager.h"
#include "nodes_stacks.h"

typedef struct
{
	Drawable *drawable;
	Fixed prev_size;
	u32 prev_flags;
	u32 prev_anchor;
	GF_List *spans;
	GF_Rect bounds;
} SVG_TextStack;

static void svg_reset_text_stack(SVG_TextStack *st)
{
	while (gf_list_count(st->spans)) {
		GF_TextSpan *span = (GF_TextSpan*)gf_list_get(st->spans, 0);
		gf_list_rem(st->spans, 0);
		gf_font_manager_delete_span(NULL, span);
	}
}

static void svg_update_bounds(SVG_TextStack *st)
{
	u32 i=0;
	GF_TextSpan *span;
	/*finally compute text bounds*/
	st->bounds.width = st->bounds.height = 0;
	st->bounds.x = st->bounds.y = 0;
	while ( (span = (GF_TextSpan*)gf_list_enum(st->spans, &i)) ) {
		gf_font_manager_refresh_span_bounds(span);
		gf_rect_union(&st->bounds, &span->bounds);
	}
}

static void svg_finalize_sort(DrawableContext *ctx, SVG_TextStack *st, GF_TraverseState * tr_state)
{
#ifndef GPAC_DISABLE_3D
	if (tr_state->visual->type_3d) {
		gf_font_spans_draw_3d(st->spans, tr_state, &ctx->aspect, 0, GF_FALSE);

		drawable_check_focus_highlight(ctx->drawable->node, tr_state, &st->bounds);
		ctx->drawable = NULL;
		return;
	}
#endif
	/*if text selection mode, we must force redraw of the entire text span because we don't
	if glyphs have been (un)selected*/
	if (!tr_state->immediate_draw &&
	        /*text selection on*/
	        (tr_state->visual->compositor->text_selection
	         /*text sel release*/
	         || (tr_state->visual->compositor->store_text_state==GF_SC_TSEL_RELEASED))
	   ) {
		GF_TextSpan *span;
		u32 i = 0;
		Bool unselect = (tr_state->visual->compositor->store_text_state==GF_SC_TSEL_RELEASED) ? GF_TRUE : GF_FALSE;
		while ((span = (GF_TextSpan*)gf_list_enum(st->spans, &i))) {
			if (span->flags & GF_TEXT_SPAN_SELECTED) {
				if (unselect) span->flags &= ~GF_TEXT_SPAN_SELECTED;
				ctx->flags |= CTX_APP_DIRTY;
			}
		}
	}
	drawable_finalize_sort(ctx, tr_state, &st->bounds);
}

/*@styles indicates font styles (PLAIN, BOLD, ITALIC, BOLDITALIC and UNDERLINED, STRIKEOUT)*/
static u32 svg_get_font_styles(GF_TraverseState * tr_state)
{
	u32 styles = 0;
	switch(*tr_state->svg_props->font_style) {
	case SVG_FONTSTYLE_ITALIC:
		styles = GF_FONT_ITALIC;
		break;
	case SVG_FONTSTYLE_OBLIQUE:
		styles = GF_FONT_OBLIQUE;
		break;
	}
	if (*tr_state->svg_props->font_variant==SVG_FONTVARIANT_SMALLCAPS)
		styles |= GF_FONT_SMALLCAPS;

	switch(*tr_state->svg_props->font_weight) {
	case SVG_FONTWEIGHT_100:
		styles |= GF_FONT_WEIGHT_100;
		break;
	case SVG_FONTWEIGHT_LIGHTER:
		styles |= GF_FONT_WEIGHT_LIGHTER;
		break;
	case SVG_FONTWEIGHT_200:
		styles |= GF_FONT_WEIGHT_200;
		break;
	case SVG_FONTWEIGHT_300:
		styles |= GF_FONT_WEIGHT_300;
		break;
	case SVG_FONTWEIGHT_400:
		styles |= GF_FONT_WEIGHT_400;
		break;
	case SVG_FONTWEIGHT_NORMAL:
		styles |= GF_FONT_WEIGHT_NORMAL;
		break;
	case SVG_FONTWEIGHT_500:
		styles |= GF_FONT_WEIGHT_500;
		break;
	case SVG_FONTWEIGHT_600:
		styles |= GF_FONT_WEIGHT_600;
		break;
	case SVG_FONTWEIGHT_700:
		styles |= GF_FONT_WEIGHT_700;
		break;
	case SVG_FONTWEIGHT_BOLD:
		styles |= GF_FONT_WEIGHT_BOLD;
		break;
	case SVG_FONTWEIGHT_800:
		styles |= GF_FONT_WEIGHT_800;
		break;
	case SVG_FONTWEIGHT_900:
		styles |= GF_FONT_WEIGHT_900;
		break;
	case SVG_FONTWEIGHT_BOLDER:
		styles |= GF_FONT_WEIGHT_BOLDER;
		break;
	}

	return styles;
}


GF_Font *gf_compositor_svg_set_font(GF_FontManager *fm, char *a_font, u32 styles, Bool check_only)
{
	GF_Font *font = NULL;
	char *fonts[50];
	u32 nb_fonts = 0;

	while (a_font) {
		char *sep;
		while (a_font[0] && strchr("\t\r\n ", a_font[0])) a_font++;

		sep = strchr(a_font, ',');
		if (sep) sep[0] = 0;

		if (a_font[0] == '\'') {
			char *sep_end = strchr(a_font+1, '\'');
			if (sep_end) sep_end[0] = 0;
			a_font++;
			fonts[nb_fonts] = gf_strdup(a_font);
			nb_fonts++;
			if (sep_end) sep_end[0] = '\'';
		} else {
			u32 skip = 0;
			size_t len = strlen(a_font)-1;

			while (a_font[len-skip] == ' ') skip++;
			if (skip) a_font[len-skip+1] = 0;
			fonts[nb_fonts] = gf_strdup(a_font);
			nb_fonts++;
			if (skip) a_font[len-skip] = ' ';
		}

		if (sep) {
			sep[0] = ',';
			a_font = sep+1;
		} else {
			a_font = NULL;
		}
		if (nb_fonts==50) break;
	}
	font = gf_font_manager_set_font_ex(fm, fonts, nb_fonts, styles, check_only);
	while (nb_fonts) {
		gf_free(fonts[nb_fonts-1]);
		nb_fonts--;
	}
	return font;
}

static GF_Font *svg_set_font(GF_TraverseState * tr_state, GF_FontManager *fm)
{
	return gf_compositor_svg_set_font(fm, tr_state->svg_props->font_family->value, svg_get_font_styles(tr_state), GF_FALSE);
}



static void svg_apply_text_anchor(GF_TraverseState * tr_state, Fixed *width)
{
	Bool reversed = GF_FALSE;
	if (!tr_state->svg_props->text_anchor) {
		*width = 0;
		return;
	}
	if (*width < 0) {
		*width *= -1;
		reversed = GF_TRUE;
	}
	switch(*tr_state->svg_props->text_anchor) {
	case SVG_TEXTANCHOR_MIDDLE:
		*width = -(*width)/2;
		break;
	case SVG_TEXTANCHOR_END:
		*width = reversed ? 0 : -(*width);
		break;
	case SVG_TEXTANCHOR_START:
	default:
		*width = reversed ? -(*width) : 0;
		break;
	}
}

static GF_TextSpan *svg_get_text_span(GF_FontManager *fm, GF_Font *font, Fixed font_size, Bool x_offsets, Bool y_offsets, Bool rotate, SVGAllAttributes *atts, char *textContent, const char *lang, GF_TraverseState *tr_state)
{
	GF_TextSpan *span = NULL;
	char *dup_text;
	u32 i, j, len;
	char prev;

	Bool preserve = (atts->xml_space && (*atts->xml_space==XML_SPACE_PRESERVE)) ? GF_TRUE : GF_FALSE;

	len = (u32) strlen(textContent);
	dup_text = (char*)gf_malloc(len+1);

	switch (tr_state->last_char_type) {
	case 2:
		prev = 0;
		break;
	case 0:
	case 1:
	default:
		prev = ' ';
		break;
	}
	for (i = 0, j = 0; i < len; i++) {
		if (textContent[i] == ' ') {
			if (prev == ' ' && !preserve) {
				/* ignore space */
			} else {
				dup_text[j] = textContent[i];
				prev = dup_text[j];
				j++;
			}
		} else if (textContent[i] == '\t') {
			if (prev == ' ' && !preserve) {
				/* ignore space */
			} else {
				dup_text[j] = ' ';
				prev = dup_text[j];
				j++;
			}
		} else if ((textContent[i] == '\n') ||
		           (textContent[i] == '\r')
		          ) {
			if (prev == ' ' && preserve) {
				dup_text[j] = ' ';
				prev = dup_text[j];
				j++;
			} else if (!i && !prev) {
				prev = dup_text[j] = ' ';
				j++;
			}
		} else if (
		    (((u8) textContent[i] == 0xc2) && ((u8) textContent[i+1] == 0xa0))
		) {
			if (prev == ' ' && !preserve) {
				/* ignore space */
			} else {
				dup_text[j] = ' ';
				prev = dup_text[j];
				j++;
			}
			i++;
		} else {
			dup_text[j] = textContent[i];
			prev = dup_text[j];
			j++;
		}
	}
	dup_text[j] = 0;
	if (!j) tr_state->last_char_type = 1;
	else tr_state->last_char_type = (dup_text[j-1]==' ') ? 1 : 2;
	/*SVG text is fliped by default (text y-axis is the inverse of SVG y-axis*/
	span = gf_font_manager_create_span(fm, font, dup_text, font_size, x_offsets, y_offsets, rotate, lang, GF_TRUE, 0, tr_state->text_parent);
	gf_free(dup_text);
	if (span) span->flags |= GF_TEXT_SPAN_HORIZONTAL;
	return span;
}



typedef struct
{
	GF_TextSpan *span;
	u32 first_glyph, last_glyph;
} textArea_state;

static void svg_text_area_reset_state(GF_TraverseState *tr_state)
{
	Fixed remain = 0;
	u32 i, count;
	count = gf_list_count(tr_state->x_anchors);

	if (tr_state->svg_props->text_align && tr_state->text_end_x) {
		switch(*tr_state->svg_props->text_align) {
		case SVG_TEXTALIGN_CENTER:
			remain = (tr_state->max_length - tr_state->text_end_x) / 2;
			break;
		case SVG_TEXTALIGN_END:
			remain = tr_state->max_length - tr_state->text_end_x;
			break;
		default:
			remain = 0;
			break;
		}
	}


	for (i=0; i<count; i++) {
		textArea_state *st = (textArea_state*)gf_list_get(tr_state->x_anchors, i);
		if (remain) {
			u32 j;
			for (j=st->first_glyph; j<st->last_glyph; j++) {
				st->span->dx[j] += remain;
			}
			tr_state->refresh_children_bounds = 1;
		}
		gf_free(st);
	}
	gf_list_reset(tr_state->x_anchors);
}

static void svg_text_area_queue_state(GF_TraverseState *tr_state, GF_TextSpan *span, u32 first_glyph, u32 last_glyph)
{
	textArea_state *st;
	u32 i, count;
	count = gf_list_count(tr_state->x_anchors);
	for (i=0; i<count; i++) {
		st = (textArea_state*)gf_list_get(tr_state->x_anchors, i);
		if (st->span==span) {
			st->last_glyph = last_glyph;
			return;
		}
	}
	st = (textArea_state*)gf_malloc(sizeof(textArea_state));
	st->first_glyph = first_glyph;
	st->last_glyph = last_glyph;
	st->span = span;
	gf_list_add(tr_state->x_anchors, st);

}

static void svg_text_area_apply_diff_baselines(GF_TraverseState *tr_state, Fixed diff)
{
	u32 i, count, j;
	count = gf_list_count(tr_state->x_anchors);
	tr_state->refresh_children_bounds++;

	for (i=0; i<count; i++) {
		textArea_state *st = (textArea_state*)gf_list_get(tr_state->x_anchors, i);

		for (j=st->first_glyph; j<st->last_glyph; j++) {
			st->span->dy[j] += diff;
		}
	}
}


static void svg_traverse_dom_text_area(GF_Node *node, SVGAllAttributes *atts, GF_TraverseState *tr_state, GF_List *spans)
{
	GF_DOMText *dom_text = (GF_DOMText *)node;
	u32 word_start;
	u32 i, j;
	Fixed line_spacing;
	GF_Font *font;
	GF_FontManager *fm;
	GF_TextSpan *span;

	if (!dom_text->textContent) return;
	if (tr_state->svg_props->font_size->value > tr_state->max_height) return;

	fm = tr_state->visual->compositor->font_manager;
	if (!fm) return;

	font = svg_set_font(tr_state, fm);
	if (!font) return;

	span = svg_get_text_span(fm, font, tr_state->svg_props->font_size->value, GF_TRUE, GF_TRUE, GF_FALSE, atts, dom_text->textContent, atts->xml_lang ? *atts->xml_lang : NULL, tr_state);
	if (!span) return;

	/*first run of the line, inc text y*/
	if (tr_state->line_spacing==0) {
		if (tr_state->svg_props->line_increment->type != SVG_NUMBER_AUTO) {
			tr_state->line_spacing = tr_state->svg_props->line_increment->value;
		} else {
			tr_state->line_spacing = gf_mulfix(span->font_size, FLT2FIX(1.0) );
		}
		tr_state->text_end_y += tr_state->line_spacing;
	}

	line_spacing = gf_mulfix(span->font_size, FLT2FIX(1.0) );

	word_start = 0;
	i = 0;
	/* boucle principale: mot par mot */
	while (i<span->nb_glyphs) {
		Fixed word_size, last_char_size, offset, word_descent;
		u32 break_glyph = 0;

		word_descent = (-span->font->descent) * span->font_scale;
		word_start = i;
		word_size = last_char_size = 0;
		while (i<span->nb_glyphs) {
			Fixed glyph_size;
			if (span->glyphs[i]) {
				/*look for word boundaries*/
				if ( (span->glyphs[i]->utf_name==' ') || (span->glyphs[i]->utf_name=='-') ) {
					last_char_size = span->glyphs[i]->horiz_advance * span->font_scale;
					i++;
					break;
				}
				glyph_size = span->glyphs[i]->horiz_advance * span->font_scale;
				if (word_size + glyph_size> tr_state->max_length) {
					break_glyph = i;
					break;
				}
				word_size += glyph_size;
			} else {
				// no glyph;
				word_size += font->max_advance_h * span->font_scale;
			}
			i++;
		}

		/* word doesn't fit on line, escape*/
		if (!word_size && !last_char_size) break;

		if (tr_state->text_end_x + word_size > tr_state->max_length) {
			/* if the word doesn't fit on line, escape*/
			if (word_size > tr_state->max_length) {
				word_start=break_glyph;
				break;
			}
			svg_text_area_reset_state(tr_state);
			tr_state->text_end_x = 0;
			tr_state->line_spacing = line_spacing;

			tr_state->text_end_y += (tr_state->svg_props->line_increment->type == SVG_NUMBER_AUTO ? tr_state->line_spacing : tr_state->svg_props->line_increment->value);
			/* out of area, abort processing*/
			if (tr_state->text_end_y > tr_state->max_height) break;
		} else {
			/* first word is too high for the area*/
			if (tr_state->text_end_y + word_descent > tr_state->max_height)
				break;

			/* stay on current line*/
			if (line_spacing > tr_state->line_spacing) {
				svg_text_area_apply_diff_baselines(tr_state, line_spacing - tr_state->line_spacing);
				tr_state->text_end_y -= tr_state->line_spacing;
				tr_state->text_end_y += line_spacing;
				tr_state->line_spacing = line_spacing;
			}

		}
		word_size += last_char_size;


		offset = tr_state->base_x + tr_state->text_end_x;
		for (j=word_start; j<i; j++) {
			span->dx[j] = offset;
			span->dy[j] = tr_state->base_y + tr_state->text_end_y;
			offset += (span->glyphs[j] ? span->glyphs[j]->horiz_advance : font->max_advance_h) * span->font_scale;
		}
		tr_state->text_end_x += word_size;
//		if (tr_state->y_step < word_height) tr_state->y_step = word_height;

		svg_text_area_queue_state(tr_state, span, word_start, i);
		word_start = i;
	}
	span->nb_glyphs = word_start;
	/*add span path to list of spans*/
	gf_list_add(spans, span);
}

static void get_domtext_width(GF_Node *node, SVGAllAttributes *atts, GF_TraverseState *tr_state)
{
	u32 i;
	GF_Font *font;
	Fixed block_width, *entry;
	GF_FontManager *fm;
	GF_TextSpan *span;
	GF_DOMText *dom_text = (GF_DOMText *)node;

	if (!dom_text->textContent) return;

	fm = tr_state->visual->compositor->font_manager;
	if (!fm) return;

	font = svg_set_font(tr_state, fm);
	if (!font) return;

	span = svg_get_text_span(fm, font, tr_state->svg_props->font_size->value, (tr_state->count_x>1), (tr_state->count_y>1), GF_FALSE, atts, dom_text->textContent, atts->xml_lang ? *atts->xml_lang : NULL, tr_state);
	if (!span) return;

	i=0;
	//count_x, _y: number of x- (y-) position of characters to come in the text flow
	while ( (i<span->nb_glyphs)
	        && ( (tr_state->count_x>1) || (tr_state->count_y>1) )
	      ) {
		block_width = (span->glyphs[i] ? span->glyphs[i]->horiz_advance : font->max_advance_h) * span->font_scale;

		//store width in tr_state->x_anchors
		entry = (Fixed*)gf_malloc(sizeof(Fixed));
		if (span->flags & GF_TEXT_SPAN_RIGHT_TO_LEFT) *entry = -block_width;
		else *entry = block_width;

		gf_list_add(tr_state->x_anchors, entry);

		if (tr_state->count_x>0) tr_state->count_x--;
		if (tr_state->count_y>0) tr_state->count_y--;
		i++;
	}

	//chars are taken one by one while there are indicated positions, then remaining chars are treated as a block
	if (i<span->nb_glyphs) {
		block_width = 0;
		while (i<span->nb_glyphs) {
			block_width += (span->glyphs[i] ? span->glyphs[i]->horiz_advance : font->max_advance_h) * span->font_scale;
			i++;
		}
		//if last indicated position, create a new item
		if ((tr_state->count_x==1)||(tr_state->count_y==1)
		        || !gf_list_count(tr_state->x_anchors) ) {
			entry = (Fixed*)gf_malloc(sizeof(Fixed));

			if (span->flags & GF_TEXT_SPAN_RIGHT_TO_LEFT) *entry = -block_width;
			else *entry = block_width;

			gf_list_add(tr_state->x_anchors, entry);
		} else { // (count_x == 0 && count_y == 0) otherwise increment last one
			Fixed *prec_lw = gf_list_last(tr_state->x_anchors);
			(*prec_lw) += block_width;
		}
		//force counters to 0 for next spans/DOM texts
		if (tr_state->count_x==1) tr_state->count_x = 0;
		if (tr_state->count_y==1) tr_state->count_y = 0;
	}
	gf_font_manager_delete_span(fm, span);
}

static void get_tspan_width(GF_Node *node, void *rs)
{
	SVGPropertiesPointers backup_props;
	u32 backup_flags;
	GF_TraverseState *tr_state = (GF_TraverseState *)rs;
	SVG_Element *tspan = (SVG_Element *)node;
	SVGAllAttributes atts;
	GF_ChildNodeItem *child;

	gf_svg_flatten_attributes(tspan, &atts);
	if (!compositor_svg_traverse_base(node, &atts, tr_state, &backup_props, &backup_flags))
		return;

	child = ((GF_ParentNode *) tspan)->children;
	while (child) {
		switch  (gf_node_get_tag(child->node)) {
		case TAG_DOMText:
			get_domtext_width(child->node, &atts, tr_state);
			break;
		case TAG_SVG_tspan:
			get_tspan_width(child->node, tr_state);
			break;
		default:
			break;
		}
		child=child->next;
	}

	memcpy(tr_state->svg_props, &backup_props, sizeof(SVGPropertiesPointers));
	tr_state->svg_flags = backup_flags;
}

void svg_traverse_domtext(GF_Node *node, SVGAllAttributes *atts, GF_TraverseState *tr_state, GF_List *spans, GF_Node *anchor_node)
{
	GF_DOMText *dom_text = (GF_DOMText *)node;
	Fixed x, y;
	u32 i;
	Fixed x_anchor, *ptr;
	GF_Font *font;
	Fixed block_width;
	GF_FontManager *fm;
	GF_TextSpan *span;

	if (!dom_text->textContent) return;

	if (tr_state->in_svg_text_area) {
		svg_traverse_dom_text_area(node, atts, tr_state, spans);
		return;
	}

	fm = tr_state->visual->compositor->font_manager;
	if (!fm) return;

	font = svg_set_font(tr_state, fm);
	if (!font) return;
	if (font->not_loaded) {
		tr_state->visual->compositor->reset_fonts = GF_TRUE;
		tr_state->visual->compositor->skip_flush = 1;
		gf_sc_next_frame_state(tr_state->visual->compositor, GF_SC_DRAW_FRAME);
		return;
	}


	span = svg_get_text_span(fm, font, tr_state->svg_props->font_size->value, (tr_state->count_x>1), (tr_state->count_y>1), tr_state->count_rotate, atts, dom_text->textContent, atts->xml_lang ? *atts->xml_lang : NULL, tr_state);
	if (!span) return;

	i=0;
	/*
	if character position is given in (x, y) attributes, use it.
	Otherwise add text at tr_state->text_end_x.
	*/
	while ((i<span->nb_glyphs)
	        && ( (tr_state->count_x>1) || (tr_state->count_y>1) )
	      ) {
		//get x and y positions
		if (tr_state->count_x==0) {
			x = tr_state->text_end_x;
		} else {
			SVG_Coordinate *xc = (SVG_Coordinate *) gf_list_get(*tr_state->text_x, tr_state->chunk_index);
			x = xc->value;
			(tr_state->count_x)--;
		}
		if (tr_state->count_y==0) {
			y = tr_state->text_end_y;
		} else {
			SVG_Coordinate *yc = (SVG_Coordinate *) gf_list_get(*tr_state->text_y, tr_state->chunk_index);
			y = yc->value;
			(tr_state->count_y)--;
		}


		/*apply x-anchor*/
		ptr = (Fixed *)gf_list_get(tr_state->x_anchors, tr_state->chunk_index);
		x_anchor = ptr ? *ptr : 0;
		if (span->dx) span->dx[i] = x_anchor + x;
		else if (!i) span->off_x = x_anchor + x;
		if (span->dy) span->dy[i] = y;
		else span->off_y = y;

		if (tr_state->count_rotate) {
			SVG_Coordinate *rc = (SVG_Coordinate *) gf_list_get(*tr_state->text_rotate, tr_state->idx_rotate);
			span->rot[i] = gf_mulfix(GF_PI/180, rc->value);
			if (tr_state->idx_rotate+1<tr_state->count_rotate) tr_state->idx_rotate++;
		}

		/*update last glyph position*/
		block_width = (span->glyphs[i] ? span->glyphs[i]->horiz_advance : font->max_advance_h) * span->font_scale;
		tr_state->text_end_x = x+block_width;
		tr_state->text_end_y = y;
		(tr_state->chunk_index)++;
		i++;
	}

	/* no more positions, add remaining glyphs as a block*/
	if (i<span->nb_glyphs) {
		Fixed offset;
		if ((tr_state->count_x==1) && tr_state->text_x) {
			SVG_Coordinate *xc = (SVG_Coordinate *) gf_list_get(*tr_state->text_x, tr_state->chunk_index);
			tr_state->text_end_x = xc->value;
			(tr_state->count_x)--;
		}
		if ((tr_state->count_y==1) && tr_state->text_y) {
			SVG_Coordinate *yc = (SVG_Coordinate *) gf_list_get(*tr_state->text_y, tr_state->chunk_index);
			tr_state->text_end_y = yc->value;
			(tr_state->count_y)--;
		}

		x = tr_state->text_end_x;
		y = tr_state->text_end_y;

		/*apply x anchor*/
		ptr = (Fixed *)gf_list_get(tr_state->x_anchors, tr_state->chunk_index);
		x_anchor = ptr ? *ptr : 0;

		offset = x_anchor + x - (span->dx ? span->dx[i] : span->off_x);

		if (!span->dx && (tr_state->text_x || x_anchor)) span->off_x = x_anchor + x;
		if (!span->dy && tr_state->text_y) span->off_y = y;

		block_width = 0;
		while (i<span->nb_glyphs) {

			if (span->rot) {
				SVG_Coordinate *rc = (SVG_Coordinate *) gf_list_get(*tr_state->text_rotate, tr_state->idx_rotate);
				span->rot[i] = gf_mulfix(GF_PI/180, rc->value);
				if (tr_state->idx_rotate+1<tr_state->count_rotate) tr_state->idx_rotate++;
			}
			if (span->dx) span->dx[i] = offset + block_width;
			if (span->dy) span->dy[i] = y;
			block_width += (span->glyphs[i] ? span->glyphs[i]->horiz_advance : font->max_advance_h) * span->font_scale;

			i++;
		}
		tr_state->text_end_x += block_width;
	}

	/*add span path to list of spans*/
	gf_list_add(spans, span);
	span->anchor = anchor_node;
}


static void svg_compute_text_width(GF_Node *node, SVGAllAttributes *atts, GF_TraverseState *tr_state )
{
	GF_ChildNodeItem *child;
	Bool is_switch = GF_FALSE;
	/*compute length of all text blocks*/
	switch  (gf_node_get_tag(node)) {
	case TAG_DOMText:
		get_domtext_width(node, atts, tr_state);
		break;
	case TAG_SVG_tspan:
		get_tspan_width(node, tr_state);
		break;
	case TAG_SVG_switch:
		is_switch = GF_TRUE;
	case TAG_SVG_a:
		child = ((GF_ParentNode *)node)->children;
		while (child) {
			if (is_switch) {
				SVGAllAttributes a_atts;
				gf_svg_flatten_attributes((SVG_Element*)child->node, &a_atts);
				if (compositor_svg_evaluate_conditional(tr_state->visual->compositor, &a_atts)) {
					svg_compute_text_width(child->node, atts, tr_state);
					break;
				}
			} else {
				svg_compute_text_width(child->node, atts, tr_state);
			}
			child = child->next;
		}
		break;
	default:
		break;
	}
}

static void svg_traverse_text_block(GF_Node *node, SVGAllAttributes *atts, GF_TraverseState *tr_state, GF_List *spans)
{
	GF_ChildNodeItem *child;
	Bool is_switch = GF_FALSE;
	switch  (gf_node_get_tag(node)) {
	case TAG_DOMText:
		svg_traverse_domtext(node, atts, tr_state, spans, NULL);
		break;
	case TAG_SVG_tspan:
		/*mark tspan as dirty to force rebuild*/
		gf_node_dirty_set(node, 0, GF_FALSE);
		gf_node_traverse(node, tr_state);
		break;
	case TAG_SVG_switch:
		is_switch = GF_TRUE;
	case TAG_SVG_a:
		child = ((GF_ParentNode *)node)->children;
		while (child) {
			if (is_switch) {
				SVGAllAttributes a_atts;
				gf_svg_flatten_attributes((SVG_Element*)child->node, &a_atts);
				if (compositor_svg_evaluate_conditional(tr_state->visual->compositor, &a_atts)) {
					svg_traverse_text_block(child->node, atts, tr_state, spans);
					break;
				}
			} else if (gf_node_get_tag(child->node)==TAG_DOMText) {
				svg_traverse_domtext(child->node, atts, tr_state, spans, node);
			}
			child = child->next;
		}
		break;
	default:
		break;
	}
}

static void svg_text_draw_2d(SVG_TextStack *st, GF_TraverseState *tr_state)
{
	gf_font_spans_draw_2d(st->spans, tr_state, 0, GF_FALSE, &st->bounds);
}


static void svg_text_area_shift_bounds(SVG_TextStack *st, GF_TraverseState *tr_state)
{
	u32 i=0;
	GF_TextSpan *span;
	/*finally compute text bounds*/
	st->bounds.width = st->bounds.height = 0;
	st->bounds.x = st->bounds.y = 0;
	while ( (span = (GF_TextSpan*)gf_list_enum(st->spans, &i)) ) {
		u32 j;
		for (j=0; j<span->nb_glyphs; j++)
			span->dy[j] += tr_state->base_shift;

		gf_font_manager_refresh_span_bounds(span);
		gf_rect_union(&st->bounds, &span->bounds);
	}
}


static void svg_traverse_text(GF_Node *node, void *rs, Bool is_destroy)
{
	SVGPropertiesPointers backup_props;
	u32 backup_flags;
	GF_Matrix2D backup_matrix;
	GF_Matrix mx3d;
	GF_ChildNodeItem *child;
	DrawableContext *ctx;
	SVG_TextStack *st = (SVG_TextStack *)gf_node_get_private(node);
	GF_TraverseState *tr_state = (GF_TraverseState *)rs;
	SVG_Element *text = (SVG_Element *)node;
	SVGAllAttributes atts;
	u32 i,imax;

	if (is_destroy) {
		drawable_del(st->drawable);
		svg_reset_text_stack(st);
		gf_list_del(st->spans);
		gf_free(st);
		return;
	}

	if (tr_state->traversing_mode==TRAVERSE_DRAW_2D) {
		svg_text_draw_2d(st, tr_state);
		return;
	}
	else if (tr_state->traversing_mode==TRAVERSE_GET_TEXT) {
		tr_state->text_parent = node;
		gf_font_spans_get_selection(node, st->spans, tr_state);
		/*and browse children*/
		child = ((GF_ParentNode *) text)->children;
		while (child) {
			switch  (gf_node_get_tag(child->node)) {
			case TAG_SVG_tspan:
				gf_node_traverse(child->node, tr_state);
				break;
			}
			child = child->next;
		}
		tr_state->text_parent = NULL;
		return;
	}

	gf_svg_flatten_attributes(text, &atts);
	if (!compositor_svg_traverse_base(node, &atts, tr_state, &backup_props, &backup_flags))
		return;

	tr_state->in_svg_text++;
	tr_state->text_parent = node;

	if (tr_state->traversing_mode==TRAVERSE_PICK) {
		compositor_svg_apply_local_transformation(tr_state, &atts, &backup_matrix, &mx3d);
		if (*tr_state->svg_props->pointer_events!=SVG_POINTEREVENTS_NONE)
			gf_font_spans_pick(node, st->spans, tr_state, &st->bounds, 1, st->drawable);

		/*and browse children*/
		child = ((GF_ParentNode *) text)->children;
		while (child) {
			switch  (gf_node_get_tag(child->node)) {
			case TAG_SVG_tspan:
				gf_node_traverse(child->node, tr_state);
				break;
			}
			child = child->next;
		}
		memcpy(tr_state->svg_props, &backup_props, sizeof(SVGPropertiesPointers));
		compositor_svg_restore_parent_transformation(tr_state, &backup_matrix, &mx3d);
		tr_state->svg_flags = backup_flags;
		tr_state->text_parent = NULL;
		tr_state->in_svg_text--;
		return;
	}
	else if (tr_state->traversing_mode==TRAVERSE_GET_TEXT) {
		gf_font_spans_get_selection(node, st->spans, tr_state);
		memcpy(tr_state->svg_props, &backup_props, sizeof(SVGPropertiesPointers));
		tr_state->svg_flags = backup_flags;
		tr_state->text_parent = NULL;
		tr_state->in_svg_text--;
		return;
	}

	compositor_svg_apply_local_transformation(tr_state, &atts, &backup_matrix, &mx3d);

	if ( (st->prev_size != tr_state->svg_props->font_size->value) ||
	        (st->prev_flags != *tr_state->svg_props->font_style) ||
	        (st->prev_anchor != *tr_state->svg_props->text_anchor) ||
	        (gf_node_dirty_get(node) & (GF_SG_SVG_GEOMETRY_DIRTY | GF_SG_CHILD_DIRTY) )
	        || tr_state->visual->compositor->reset_fonts
	   ) {
		u32 mode;
		child = ((GF_ParentNode *) text)->children;

		svg_reset_text_stack(st);
		tr_state->text_end_x = 0;
		tr_state->text_end_y = 0;
		/*init the xml:space algo*/
		tr_state->last_char_type = 0;

		/*initialize x and y counters - stored at the traverse level for handling tspan & co*/
		if (atts.text_x) tr_state->count_x = gf_list_count(*atts.text_x);
		else tr_state->count_x=0;
		if (atts.text_y) tr_state->count_y = gf_list_count(*atts.text_y);
		else tr_state->count_y=0;
		if (atts.text_rotate) tr_state->count_rotate = gf_list_count(*atts.text_rotate);
		else tr_state->count_rotate=0;

		/*horizontal justifiers container*/
		tr_state->x_anchors = gf_list_new();

		/*compute length of all text blocks*/
		while (child) {
			svg_compute_text_width(child->node, &atts, tr_state);
			child=child->next;
		}

		/*apply justification of all blocks*/
		imax=gf_list_count(tr_state->x_anchors);
		for (i=0; i<imax; i++) {
			Fixed *lw = gf_list_get(tr_state->x_anchors, i);
			svg_apply_text_anchor(tr_state, lw);
		}

		/*re-initialize x and y counters for final compute*/
		if (atts.text_x) tr_state->count_x = gf_list_count(*atts.text_x);
		else tr_state->count_x=0;
		if (atts.text_y) tr_state->count_y = gf_list_count(*atts.text_y);
		else tr_state->count_y=0;
		if (atts.text_rotate) tr_state->count_rotate = gf_list_count(*atts.text_rotate);
		else tr_state->count_rotate=0;
		tr_state->idx_rotate = 0;
		tr_state->chunk_index = 0;

		/*initialize current text position*/
		if (!tr_state->text_end_x) {
			SVG_Coordinate *xc = (atts.text_x ? (SVG_Coordinate *) gf_list_get(*atts.text_x, 0) : NULL);
			tr_state->text_end_x = (xc ? xc->value : 0);
		}
		if (!tr_state->text_end_y) {
			SVG_Coordinate *yc = (atts.text_y ? (SVG_Coordinate *) gf_list_get(*atts.text_y, 0) : NULL);
			tr_state->text_end_y = (yc ? yc->value : 0);
		}

		/*pass x and y to children*/
		tr_state->text_x = atts.text_x;
		tr_state->text_y = atts.text_y;
		tr_state->text_rotate = atts.text_rotate;

		drawable_reset_path(st->drawable);

		/*switch to bounds mode, and recompute children*/
		mode = tr_state->traversing_mode;
		tr_state->traversing_mode = TRAVERSE_GET_BOUNDS;
		tr_state->last_char_type = 0;

		child = ((GF_ParentNode *) text)->children;
		while (child) {
			svg_traverse_text_block(child->node, &atts, tr_state, st->spans);
			child = child->next;
		}
		tr_state->traversing_mode = mode;
		gf_node_dirty_clear(node, 0);
		drawable_mark_modified(st->drawable, tr_state);
		st->prev_size = tr_state->svg_props->font_size->value;
		st->prev_flags = *tr_state->svg_props->font_style;
		st->prev_anchor = *tr_state->svg_props->text_anchor;

		while (gf_list_count(tr_state->x_anchors)) {
			Fixed *f = gf_list_last(tr_state->x_anchors);
			gf_list_rem_last(tr_state->x_anchors);
			gf_free(f);
		}
		gf_list_del(tr_state->x_anchors);
		tr_state->x_anchors = NULL;

		svg_update_bounds(st);
	}

	if (tr_state->traversing_mode == TRAVERSE_GET_BOUNDS) {
		if (!compositor_svg_is_display_off(tr_state->svg_props))
			tr_state->bounds = st->bounds;

	} else if ((tr_state->traversing_mode == TRAVERSE_SORT)
		&& !compositor_svg_is_display_off(tr_state->svg_props)
		&& (*(tr_state->svg_props->visibility) != SVG_VISIBILITY_HIDDEN)
	  ) {
		ctx = drawable_init_context_svg(st->drawable, tr_state, atts.clip_path);

		if (ctx) svg_finalize_sort(ctx, st, tr_state);

		/*and browse children*/
		child = ((GF_ParentNode *) text)->children;
		while (child) {
			switch  (gf_node_get_tag(child->node)) {
			case TAG_SVG_tspan:
				gf_node_traverse(child->node, tr_state);
				break;
			case TAG_SVG_switch:
				gf_node_traverse(child->node, tr_state);
				break;
			}
			child = child->next;
		}
	}
	tr_state->in_svg_text--;
	tr_state->text_parent = NULL;

	compositor_svg_restore_parent_transformation(tr_state, &backup_matrix, &mx3d);
	memcpy(tr_state->svg_props, &backup_props, sizeof(SVGPropertiesPointers));
	tr_state->svg_flags = backup_flags;
}


void compositor_init_svg_text(GF_Compositor *compositor, GF_Node *node)
{
	SVG_TextStack *stack;
	GF_SAFEALLOC(stack, SVG_TextStack);
	if (!stack) {
		GF_LOG(GF_LOG_ERROR, GF_LOG_COMPOSE, ("[Compositor] Failed to allocate svg text stack\n"));
		return;
	}
	stack->drawable = drawable_new();
	stack->drawable->node = node;
	stack->drawable->flags = DRAWABLE_USE_TRAVERSE_DRAW;
	stack->spans = gf_list_new();
	gf_node_set_private(node, stack);
	gf_node_set_callback_function(node, svg_traverse_text);
}


static void svg_traverse_tspan(GF_Node *node, void *rs, Bool is_destroy)
{
	SVGPropertiesPointers backup_props;
	u32 backup_flags;
	GF_Matrix2D backup_matrix;
	GF_Matrix mx3d;
	DrawableContext *ctx;
	SVG_TextStack *st = (SVG_TextStack *)gf_node_get_private(node);
	GF_TraverseState *tr_state = (GF_TraverseState *)rs;
	SVG_Element *tspan = (SVG_Element *)node;
	SVGAllAttributes atts;
	GF_ChildNodeItem *child;

	if (is_destroy) {
		drawable_del(st->drawable);
		svg_reset_text_stack(st);
		gf_list_del(st->spans);
		gf_free(st);
		return;
	}
	if (tr_state->traversing_mode==TRAVERSE_DRAW_2D) {
		svg_text_draw_2d(st, tr_state);
		return;
	}
	else if (tr_state->traversing_mode==TRAVERSE_GET_TEXT) {
		gf_font_spans_get_selection(node, st->spans, tr_state);
		/*and browse children*/
		child = ((GF_ParentNode *) tspan)->children;
		while (child) {
			switch  (gf_node_get_tag(child->node)) {
			case TAG_SVG_tspan:
				gf_node_traverse(child->node, tr_state);
				break;
			}
			child = child->next;
		}
		return;
	}

	if (!tr_state->in_svg_text && !tr_state->in_svg_text_area) return;

	gf_svg_flatten_attributes(tspan, &atts);
	if (!compositor_svg_traverse_base(node, &atts, tr_state, &backup_props, &backup_flags))
		return;

	if (tr_state->traversing_mode==TRAVERSE_PICK) {
		if (*tr_state->svg_props->pointer_events!=SVG_POINTEREVENTS_NONE)
			gf_font_spans_pick(node, st->spans, tr_state, &st->bounds, GF_TRUE, st->drawable);

		/*and browse children*/
		child = ((GF_ParentNode *) tspan)->children;
		while (child) {
			switch  (gf_node_get_tag(child->node)) {
			case TAG_SVG_tspan:
				gf_node_traverse(child->node, tr_state);
				break;
			}
			child = child->next;
		}
		memcpy(tr_state->svg_props, &backup_props, sizeof(SVGPropertiesPointers));
		tr_state->svg_flags = backup_flags;
		return;
	}

	compositor_svg_apply_local_transformation(tr_state, &atts, &backup_matrix, &mx3d);

	if ( (st->prev_size != tr_state->svg_props->font_size->value) ||
	        (st->prev_flags != *tr_state->svg_props->font_style) ||
	        (st->prev_anchor != *tr_state->svg_props->text_anchor) ||
	        (gf_node_dirty_get(node) & (GF_SG_SVG_GEOMETRY_DIRTY | GF_SG_CHILD_DIRTY) )
	   ) {
		u32 mode;

		/*tspan has been modified in the SORT stage, which means that an anim local to tspan has modified the node.
		The result of the parent (text, textArea) will thus be wrong if we try to update the tspan. We therefore
		keep the previous computed drawable, and invalidate the parent for next frame*/
		if (tr_state->traversing_mode==TRAVERSE_SORT) {
			gf_node_dirty_set(node, 0, GF_TRUE);
			goto skip_changes;
		}

		/*switch to bounds mode, and recompute children*/
		mode = tr_state->traversing_mode;
		tr_state->traversing_mode = TRAVERSE_GET_BOUNDS;

		svg_reset_text_stack(st);
		child = ((GF_ParentNode *) tspan)->children;

		while (child) {
			switch  (gf_node_get_tag(child->node)) {
			case TAG_DOMText:
				svg_traverse_domtext(child->node, &atts, tr_state, st->spans, NULL);
				break;
			case TAG_SVG_tspan:
				gf_node_dirty_set(child->node, 0, GF_FALSE);
				gf_node_traverse(child->node, tr_state);
				break;
			case TAG_SVG_switch:
			case TAG_SVG_a:
			case TAG_SVG_tbreak:
				gf_node_traverse(child->node, tr_state);
				break;
			default:
				break;
			}
			child = child->next;
		}
		tr_state->traversing_mode = mode;
		gf_node_dirty_clear(node, 0);
		drawable_mark_modified(st->drawable, tr_state);
		st->prev_size = tr_state->svg_props->font_size->value;
		st->prev_flags = *tr_state->svg_props->font_style;
		st->prev_anchor = *tr_state->svg_props->text_anchor;

		svg_update_bounds(st);
	}
skip_changes:

	if (tr_state->traversing_mode == TRAVERSE_GET_BOUNDS) {
		if (tr_state->refresh_children_bounds) {
			if (tr_state->base_shift)
				svg_text_area_shift_bounds(st, tr_state);
			else
				svg_update_bounds(st);
			child = ((GF_ParentNode *) tspan)->children;
			while (child) {
				switch  (gf_node_get_tag(child->node)) {
				case TAG_SVG_tspan:
				case TAG_SVG_switch:
				case TAG_SVG_a:
					gf_node_traverse(child->node, tr_state);
					break;
				default:
					break;
				}
				child = child->next;
			}
		}
		if (!compositor_svg_is_display_off(tr_state->svg_props))
			tr_state->bounds = st->bounds;

	}
	else if (
	    (tr_state->traversing_mode == TRAVERSE_SORT)
	    && !compositor_svg_is_display_off(tr_state->svg_props)
	    && ( *(tr_state->svg_props->visibility) != SVG_VISIBILITY_HIDDEN)
	) {
		child = ((GF_ParentNode *) tspan)->children;

		ctx = drawable_init_context_svg(st->drawable, tr_state, atts.clip_path);

		if (ctx) svg_finalize_sort(ctx, st, tr_state);

		while (child) {
			switch  (gf_node_get_tag(child->node)) {
			case TAG_SVG_tspan:
			case TAG_SVG_switch:
			case TAG_SVG_a:
				gf_node_traverse(child->node, tr_state);
				break;
			default:
				break;
			}
			child = child->next;
		}
	}

	compositor_svg_restore_parent_transformation(tr_state, &backup_matrix, &mx3d);
	memcpy(tr_state->svg_props, &backup_props, sizeof(SVGPropertiesPointers));
	tr_state->svg_flags = backup_flags;
}

void compositor_init_svg_tspan(GF_Compositor *compositor, GF_Node *node)
{
	SVG_TextStack *stack;
	GF_SAFEALLOC(stack, SVG_TextStack);
	if (!stack) {
		GF_LOG(GF_LOG_ERROR, GF_LOG_COMPOSE, ("[Compositor] Failed to allocate svg tspan stack\n"));
		return;
	}
	stack->drawable = drawable_new();
	stack->drawable->node = node;
	stack->drawable->flags = DRAWABLE_USE_TRAVERSE_DRAW;
	stack->spans = gf_list_new();
	gf_node_set_private(node, stack);
	gf_node_set_callback_function(node, svg_traverse_tspan);
}


static void svg_traverse_textArea(GF_Node *node, void *rs, Bool is_destroy)
{
	SVGPropertiesPointers backup_props;
	u32 backup_flags;
	GF_Matrix mx3d;
	GF_Matrix2D backup_matrix;
	DrawableContext *ctx = NULL;
	GF_ChildNodeItem *child;
	SVG_TextStack *st = (SVG_TextStack *)gf_node_get_private(node);
	GF_TraverseState *tr_state = (GF_TraverseState *)rs;
	SVG_Element *text = (SVG_Element *)node;
	SVGAllAttributes atts;

	if (is_destroy) {
		drawable_del(st->drawable);
		svg_reset_text_stack(st);
		gf_list_del(st->spans);
		gf_free(st);
		return;
	}

	if (tr_state->traversing_mode==TRAVERSE_DRAW_2D) {
		svg_text_draw_2d(st, tr_state);
		return;
	}
	else if (tr_state->traversing_mode==TRAVERSE_GET_TEXT) {
		tr_state->text_parent = node;
		gf_font_spans_get_selection(node, st->spans, tr_state);
		/*and browse children*/
		child = ((GF_ParentNode *) text)->children;
		while (child) {
			switch  (gf_node_get_tag(child->node)) {
			case TAG_SVG_tspan:
			case TAG_SVG_a:
				gf_node_traverse(child->node, tr_state);
				break;
			}
			child = child->next;
		}
		tr_state->text_parent = NULL;
		return;
	}


	gf_svg_flatten_attributes(text, &atts);
	if (!compositor_svg_traverse_base(node, &atts, tr_state, &backup_props, &backup_flags))
		return;

	tr_state->text_parent = node;
	tr_state->in_svg_text_area++;

	if (tr_state->traversing_mode==TRAVERSE_PICK) {
		if (*tr_state->svg_props->pointer_events!=SVG_POINTEREVENTS_NONE) {
			compositor_svg_apply_local_transformation(tr_state, &atts, &backup_matrix, &mx3d);
			gf_font_spans_pick(node, st->spans, tr_state, &st->bounds, GF_TRUE, st->drawable);

			/*and browse children*/
			child = ((GF_ParentNode *) node)->children;
			while (child) {
				gf_node_traverse(child->node, tr_state);
				child = child->next;
			}
			compositor_svg_restore_parent_transformation(tr_state, &backup_matrix, &mx3d);
			memcpy(tr_state->svg_props, &backup_props, sizeof(SVGPropertiesPointers));
			tr_state->svg_flags = backup_flags;
		}
		tr_state->in_svg_text_area--;
		tr_state->text_parent = NULL;
		return;
	}

	compositor_svg_apply_local_transformation(tr_state, &atts, &backup_matrix, &mx3d);

	if ( (st->prev_size != tr_state->svg_props->font_size->value) ||
	        (st->prev_flags != *tr_state->svg_props->font_style) ||
	        (st->prev_anchor != *tr_state->svg_props->text_anchor) ||
	        (gf_node_dirty_get(node) & (GF_SG_SVG_GEOMETRY_DIRTY | GF_SG_CHILD_DIRTY) )
	        || tr_state->visual->compositor->reset_fonts
	   ) {
		u32 mode;

		svg_reset_text_stack(st);
		gf_node_dirty_clear(node, 0);
		drawable_mark_modified(st->drawable, tr_state);
		drawable_reset_path(st->drawable);

		tr_state->max_length = (atts.width ? (atts.width->type == SVG_NUMBER_AUTO ? FIX_MAX : atts.width->value) : FIX_MAX);
		tr_state->max_height = (atts.height ? (atts.height->type == SVG_NUMBER_AUTO ? FIX_MAX : atts.height->value) : FIX_MAX);
		tr_state->base_x = (atts.x ? atts.x->value : 0);
		tr_state->base_y = (atts.y ? atts.y->value : 0);
		/*init the xml:space algo*/
		tr_state->last_char_type = 0;
		/*let it initialize from first font*/
		tr_state->line_spacing = 0;
		tr_state->text_end_x = 0;
		tr_state->text_end_y = (tr_state->svg_props->line_increment->type == SVG_NUMBER_AUTO ? 0 : tr_state->svg_props->line_increment->value);

		if (tr_state->svg_props->font_size && (tr_state->svg_props->font_size->value <= tr_state->max_height)) {
			Fixed remain;
			u32 c, refresh_to_idx, prev_refresh;
			tr_state->x_anchors = gf_list_new();

			/*switch to bounds mode, and recompute children*/
			mode = tr_state->traversing_mode;
			tr_state->traversing_mode = TRAVERSE_GET_BOUNDS;

			prev_refresh = tr_state->refresh_children_bounds;
			tr_state->refresh_children_bounds = 0;
			c = refresh_to_idx = 0;
			child = ((GF_ParentNode *) text)->children;
			while (child) {
				c++;
				switch  (gf_node_get_tag(child->node)) {
				case TAG_DOMText:
					svg_traverse_dom_text_area(child->node, &atts, tr_state, st->spans);
					break;
				case TAG_SVG_tspan:
					/*mark tspan as dirty to force rebuild*/
					gf_node_dirty_set(child->node, 0, GF_FALSE);
					gf_node_traverse(child->node, tr_state);
					break;
				case TAG_SVG_switch:
				case TAG_SVG_a:
				case TAG_SVG_tbreak:
					gf_node_traverse(child->node, tr_state);
					break;
				default:
					break;
				}
				if (tr_state->refresh_children_bounds) {
					tr_state->refresh_children_bounds=0;
					refresh_to_idx=c;
				}

				child=child->next;
			}
			st->prev_size = tr_state->svg_props->font_size->value;
			st->prev_flags = *tr_state->svg_props->font_style;
			st->prev_anchor = *tr_state->svg_props->text_anchor;

			svg_text_area_reset_state(tr_state);
			gf_list_del(tr_state->x_anchors);
			tr_state->x_anchors = NULL;

			if (tr_state->refresh_children_bounds) {
				refresh_to_idx = (u32) -1;
				tr_state->base_shift = 0;
			}
			if (tr_state->svg_props->display_align) {
				switch (*tr_state->svg_props->display_align) {
				case SVG_DISPLAYALIGN_CENTER:
					remain = (tr_state->max_height-tr_state->text_end_y) / 2;
					break;
				case SVG_DISPLAYALIGN_AFTER:
					remain = tr_state->max_height - tr_state->text_end_y;
					break;
				default:
					remain = 0;
					break;
				}
				if (remain<0) remain=0;
				if (remain) {
					refresh_to_idx = (u32) -1;
					tr_state->base_shift = remain;
					svg_text_area_shift_bounds(st, tr_state);
				}
			}

			if (refresh_to_idx) {
				tr_state->refresh_children_bounds=1;
				/*and retraverse in case of bounds adjustements*/
				child = ((GF_ParentNode *) text)->children;
				while (child) {
					switch (gf_node_get_tag(child->node)) {
					case TAG_DOMText:
						break;
					case TAG_SVG_tspan:
					case TAG_SVG_switch:
					case TAG_SVG_a:
						gf_node_traverse(child->node, tr_state);
						break;
					default:
						break;
					}
					child=child->next;
					refresh_to_idx--;
					if (!refresh_to_idx) break;
				}
				tr_state->base_shift = 0;
			}
			tr_state->traversing_mode = mode;
			tr_state->refresh_children_bounds = prev_refresh;
		}
		svg_update_bounds(st);
	}

	if (tr_state->traversing_mode == TRAVERSE_GET_BOUNDS) {
		if (!compositor_svg_is_display_off(tr_state->svg_props))
			tr_state->bounds = st->bounds;
	} else if ( (tr_state->traversing_mode == TRAVERSE_SORT)
	            && !compositor_svg_is_display_off(tr_state->svg_props)
	            && (*(tr_state->svg_props->visibility) != SVG_VISIBILITY_HIDDEN)
	          ) {

		ctx = drawable_init_context_svg(st->drawable, tr_state, atts.clip_path);

		if (ctx) svg_finalize_sort(ctx, st, tr_state);

		child = ((GF_ParentNode *) text)->children;
		while (child) {
			switch  (gf_node_get_tag(child->node)) {
			case TAG_DOMText:
				break;
			case TAG_SVG_tspan:
			case TAG_SVG_switch:
			case TAG_SVG_a:
				gf_node_traverse(child->node, tr_state);
				break;
			default:
				break;
			}
			child = child->next;
		}
	}
	tr_state->in_svg_text_area--;
	tr_state->text_parent = NULL;


	compositor_svg_restore_parent_transformation(tr_state, &backup_matrix, &mx3d);
	memcpy(tr_state->svg_props, &backup_props, sizeof(SVGPropertiesPointers));
	tr_state->svg_flags = backup_flags;
}

void compositor_init_svg_textarea(GF_Compositor *compositor, GF_Node *node)
{
	SVG_TextStack *stack;
	GF_SAFEALLOC(stack, SVG_TextStack);
	if (!stack) {
		GF_LOG(GF_LOG_ERROR, GF_LOG_COMPOSE, ("[Compositor] Failed to allocate svg textarea stack\n"));
		return;
	}
	stack->drawable = drawable_new();
	stack->drawable->node = node;
	stack->drawable->flags = DRAWABLE_USE_TRAVERSE_DRAW;
	stack->spans = gf_list_new();
	gf_node_set_private(node, stack);
	gf_node_set_callback_function(node, svg_traverse_textArea);
}

static void svg_traverse_tbreak(GF_Node *node, void *rs, Bool is_destroy)
{
	SVGPropertiesPointers backup_props;
	u32 backup_flags;
	GF_TraverseState *tr_state = (GF_TraverseState *)rs;
	SVGAllAttributes atts;

	if (is_destroy) return;
	if (tr_state->traversing_mode!=TRAVERSE_GET_BOUNDS) return;

	gf_svg_flatten_attributes((SVG_Element*)node, &atts);
	if (!compositor_svg_traverse_base(node, &atts, tr_state, &backup_props, &backup_flags))
		return;

	svg_text_area_reset_state(tr_state);
	/*beginning of a line, force a break of current fontSize*/
	if (!tr_state->text_end_x) {
		if (tr_state->svg_props->line_increment->type != SVG_NUMBER_AUTO) {
			tr_state->text_end_y += tr_state->svg_props->line_increment->value;
		} else {
			tr_state->text_end_y += tr_state->svg_props->font_size->value;
		}
	}
	tr_state->line_spacing = 0;
	tr_state->text_end_x = 0;
	tr_state->last_char_type = 0;

	memcpy(tr_state->svg_props, &backup_props, sizeof(SVGPropertiesPointers));
	tr_state->svg_flags = backup_flags;
}

void compositor_init_svg_tbreak(GF_Compositor *compositor, GF_Node *node)
{
	gf_node_set_callback_function(node, svg_traverse_tbreak);
}

#endif //!defined(GPAC_DISABLE_SVG) &&  !defined(GPAC_DISABLE_COMPOSITOR)