layout.c

一个用于智能手机的多媒体库适合S60 WinCE的跨平台开发库

/*
 *			GPAC - Multimedia Framework C SDK
 *
 *			Copyright (c) Jean Le Feuvre 2000-2005
 *					All rights reserved
 *
 *  This file is part of GPAC / 2D rendering module
 *
 *  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 "stacks2d.h"
#include "grouping.h"
#include "visualsurface2d.h"

typedef struct
{
	Fixed width, height, ascent, descent;
	u32 first_child, nb_children;
} LineInfo;

typedef struct
{
	GF_Node *owner;
	GF_Renderer *compositor;
	GROUPINGNODESTACK2D
	
	Bool start_scroll, is_scrolling;
	Double start_time, pause_time;
	GF_List *lines;
	GF_Rect clip;
	Fixed last_scroll, prev_rate, scroll_rate, scale_scroll, scroll_len, scroll_min, scroll_max;
} LayoutStack;

static void layout_reset_lines(LayoutStack *st)
{
	while (gf_list_count(st->lines)) {
		LineInfo *li = (LineInfo *)gf_list_get(st->lines, 0);
		gf_list_rem(st->lines, 0);
		free(li);
	}
}

static LineInfo *new_line_info(LayoutStack *st)
{
	LineInfo *li;
	GF_SAFEALLOC(li, LineInfo);
	gf_list_add(st->lines, li);
	return li;
}
static GFINLINE LineInfo *get_line_info(LayoutStack *st, u32 i)
{
	return (LineInfo *) gf_list_get(st->lines, i);
}




enum
{
	L_FIRST,
	L_BEGIN,
	L_MIDDLE,
	L_END,
};

static u32 get_justify(M_Layout *l, u32 i)
{
	if (l->justify.count <= i) return L_BEGIN;
	if (!strcmp(l->justify.vals[i], "END")) return L_END;
	if (!strcmp(l->justify.vals[i], "MIDDLE")) return L_MIDDLE;
	if (!strcmp(l->justify.vals[i], "FIRST")) return L_FIRST;
	return L_BEGIN;
}

static void get_lines_info(LayoutStack *st, M_Layout *l)
{
	u32 i, count;
	LineInfo *li;
	Fixed max_w, max_h;

	max_w = st->clip.width;
	max_h = st->clip.height;
	layout_reset_lines(st);
	
	count = gf_list_count(st->groups);
	if (!count) return;

	li = new_line_info(st);
	li->first_child = 0;

	for (i=0; i<count; i++) {
		ChildGroup2D *cg = (ChildGroup2D *)gf_list_get(st->groups, i);
		if (!l->horizontal) {
			/*check if exceed column size or not - if so, move to next column or clip given wrap mode*/
			if (cg->final.height + li->height > max_h) {
				if (l->wrap) {
					li = new_line_info(st);
					li->first_child = i;
				}
			}
			if (cg->final.width > li->width) li->width = cg->final.width;
			li->height += cg->final.height;
			li->nb_children ++;
		} else {
			if (i && (cg->final.width + li->width> max_w)) {
				if (l->wrap) {
					if (!li->ascent) {
						li->ascent = li->height;
						li->descent = 0;
					}

					li = new_line_info(st);
					li->first_child = i;
				} 
			}
		
			/*get ascent/descent for text or height for non-text*/
			if (cg->is_text_group) {
				if (li->ascent < cg->ascent) li->ascent = cg->ascent;
				if (li->descent < cg->descent) li->descent = cg->descent;
				if (li->height < li->ascent + li->descent) li->height = li->ascent + li->descent;
			} else if (cg->final.height > li->height) {
				li->height = cg->final.height;
			}
			li->width += cg->final.width;
			li->nb_children ++;
		}
	}
}


static void layout_justify(LayoutStack *st, M_Layout *l)
{
	u32 first, minor, major, i, k, nbLines;
	Fixed current_top, current_left, h;
	LineInfo *li;
	ChildGroup2D *cg, *prev;
	get_lines_info(st, l);
	major = get_justify(l, 0);
	minor = get_justify(l, 1);

	st->scroll_len = 0;

	nbLines = gf_list_count(st->lines);
	if (l->horizontal) {
		if (l->wrap && !l->topToBottom) {
			li = (LineInfo*)gf_list_get(st->lines, 0);
			current_top = st->clip.y - st->clip.height;
			if (li) current_top += li->height;
		} else {
			current_top = st->clip.y;
		}

		/*for each line perform adjustment*/
		for (k=0; k<nbLines; k++) {
			li = (LineInfo*)gf_list_get(st->lines, k);
			first = li->first_child;
			if (!l->leftToRight) first += li->nb_children - 1;

			if (!l->topToBottom && k) current_top += li->height;
			
			/*set major alignment (X) */
			cg = (ChildGroup2D *)gf_list_get(st->groups, first);
			switch (major) {
			case L_END:
				cg->final.x = st->clip.x + st->clip.width - li->width;
				break;
			case L_MIDDLE:
				cg->final.x = st->clip.x + (st->clip.width - li->width)/2;
				break;
			case L_FIRST:
			case L_BEGIN:
				cg->final.x = st->clip.x;
				break;
			}          

			/*for each in the run */
			i = first;
			while (1) {
				cg = (ChildGroup2D *)gf_list_get(st->groups, i);
				h = MAX(li->ascent, li->height);
				switch (minor) {
				case L_FIRST:
					cg->final.y = current_top - h;
					if (cg->is_text_group) {
						cg->final.y += cg->ascent;
					} else {
						cg->final.y += cg->final.height;
					}
					break;
				case L_MIDDLE:
					cg->final.y = current_top - (h - cg->final.height)/2;
					break;
				case L_END:
					cg->final.y = current_top;
					break;
				case L_BEGIN:
				default:
					cg->final.y = current_top - h + cg->final.height;
					break;
				}
				/*update left for non-first children in line*/
				if (i != first) {
					if (l->leftToRight) {
						prev = (ChildGroup2D *)gf_list_get(st->groups, i-1);
					} else {
						prev = (ChildGroup2D *)gf_list_get(st->groups, i+1);
					}
					cg->final.x = prev->final.x + prev->final.width;
				}
				i += l->leftToRight ? +1 : -1;
				if (l->leftToRight && (i==li->first_child + li->nb_children))
					break;
				else if (!l->leftToRight && (i==li->first_child - 1))
					break;		
			}
			if (l->topToBottom) {
				current_top -= gf_mulfix(l->spacing, li->height);
			} else {
				current_top += gf_mulfix(l->spacing - 1, li->height);
			}

			if (l->scrollVertical) {
				st->scroll_len += li->height;
			} else {
				if (st->scroll_len < li->width) st->scroll_len = li->width;
			}
		}
		return;
	}

	/*Vertical aligment*/
	li = (LineInfo*)gf_list_get(st->lines, 0);
	if (l->wrap && !l->leftToRight) {
		current_left = st->clip.x + st->clip.width;
		if (li) current_left -= li->width;
	} else {
		current_left = st->clip.x;
		switch (minor) {
		case L_MIDDLE: current_left += (st->clip.width - li->width)/2; break;
		case L_END: current_left += st->clip.width - li->width; break;
		case L_BEGIN:
		case L_FIRST:
		default:
			break;
		}
	}

	/*for all columns in run*/
	for (k=0; k<nbLines; k++) {
		li = (LineInfo*)gf_list_get(st->lines, k);

		first = li->first_child;
		if (!l->topToBottom) first += li->nb_children - 1;
		
		/*set major alignment (Y) */
		cg = (ChildGroup2D *)gf_list_get(st->groups, first);
		switch (major) {
		case L_END:
			cg->final.y = st->clip.y - st->clip.height + li->height;
			break;
		case L_MIDDLE:
			cg->final.y = st->clip.y - st->clip.height/2 + li->height/2;
			break;
		case L_FIRST:
		case L_BEGIN:
			cg->final.y = st->clip.y;
			break;
		}          

		/*for each in the run */
		i = first;
		while (1) {
			cg = (ChildGroup2D *)gf_list_get(st->groups, i);
			switch (minor) {
			case L_MIDDLE:
				cg->final.x = current_left + li->width/2 - cg->final.width/2;
				break;
			case L_END:
				cg->final.x = current_left + li->width - cg->final.width;
				break;
			case L_BEGIN:
			case L_FIRST:
			default:
				cg->final.x = current_left;
				break;
			}
			/*update top for non-first children in line*/
			if (i != first) {
				if (l->topToBottom) {
					prev = (ChildGroup2D *)gf_list_get(st->groups, i-1);
				} else {
					prev = (ChildGroup2D *)gf_list_get(st->groups, i+1);
				}
				cg->final.y = prev->final.y - prev->final.height;
			}
			i += l->topToBottom ? +1 : -1;
			if (l->topToBottom && (i==li->first_child + li->nb_children))
				break;
			else if (!l->topToBottom && (i==li->first_child - 1))
				break;		
		}
		if (l->leftToRight) {
			current_left += gf_mulfix(l->spacing, li->width);
		} else if (k < nbLines - 1) {