netsurf/render/box.h

219 lines
7.0 KiB
C

/*
* This file is part of NetSurf, http://netsurf.sourceforge.net/
* Licensed under the GNU General Public License,
* http://www.opensource.org/licenses/gpl-license
* Copyright 2004 James Bursa <bursa@users.sourceforge.net>
* Copyright 2003 Phil Mellor <monkeyson@users.sourceforge.net>
*/
/** \file
* Conversion of XML tree to box tree (interface).
*
* This stage of rendering converts a tree of xmlNodes (produced by libxml2)
* to a tree of struct box. The box tree represents the structure of the
* document as given by the CSS display and float properties.
*
* For example, consider the following HTML:
* \code
* <h1>Example Heading</h1>
* <p>Example paragraph <em>with emphasised text</em> etc.</p> \endcode
*
* This would produce approximately the following box tree with default CSS
* rules:
* \code
* BOX_BLOCK (corresponds to h1)
* BOX_INLINE_CONTAINER
* BOX_INLINE "Example Heading"
* BOX_BLOCK (p)
* BOX_INLINE_CONTAINER
* BOX_INLINE "Example paragraph "
* BOX_INLINE "with emphasised text" (em)
* BOX_INLINE "etc." \endcode
*
* Note that the em has been collapsed into the INLINE_CONTAINER.
*
* If these CSS rules were applied:
* \code
* h1 { display: table-cell }
* p { display: table-cell }
* em { float: left; width: 5em } \endcode
*
* then the box tree would instead look like this:
* \code
* BOX_TABLE
* BOX_TABLE_ROW_GROUP
* BOX_TABLE_ROW
* BOX_TABLE_CELL (h1)
* BOX_INLINE_CONTAINER
* BOX_INLINE "Example Heading"
* BOX_TABLE_CELL (p)
* BOX_INLINE_CONTAINER
* BOX_INLINE "Example paragraph "
* BOX_FLOAT_LEFT (em)
* BOX_BLOCK
* BOX_INLINE_CONTAINER
* BOX_INLINE "with emphasised text"
* BOX_INLINE "etc." \endcode
*
* Here implied boxes have been added and a float is present.
*
* A box tree is "normalized" if the following is satisfied:
* \code
* parent permitted child nodes
* BLOCK, INLINE_BLOCK BLOCK, INLINE_CONTAINER, TABLE
* INLINE_CONTAINER INLINE, INLINE_BLOCK, FLOAT_LEFT, FLOAT_RIGHT, BR
* INLINE none
* TABLE at least 1 TABLE_ROW_GROUP
* TABLE_ROW_GROUP at least 1 TABLE_ROW
* TABLE_ROW at least 1 TABLE_CELL
* TABLE_CELL BLOCK, INLINE_CONTAINER, TABLE (same as BLOCK)
* FLOAT_(LEFT|RIGHT) exactly 1 BLOCK or TABLE \endcode
*/
#ifndef _NETSURF_RENDER_BOX_H_
#define _NETSURF_RENDER_BOX_H_
#include <limits.h>
#include <stdbool.h>
#include "libxml/HTMLparser.h"
#include "netsurf/utils/config.h"
#include "netsurf/css/css.h"
#include "netsurf/render/font.h"
#include "netsurf/utils/pool.h"
typedef enum {
BOX_BLOCK, BOX_INLINE_CONTAINER, BOX_INLINE,
BOX_TABLE, BOX_TABLE_ROW, BOX_TABLE_CELL,
BOX_TABLE_ROW_GROUP,
BOX_FLOAT_LEFT, BOX_FLOAT_RIGHT,
BOX_INLINE_BLOCK, BOX_BR
} box_type;
struct column {
enum { COLUMN_WIDTH_UNKNOWN = 0, COLUMN_WIDTH_FIXED,
COLUMN_WIDTH_AUTO, COLUMN_WIDTH_PERCENT,
COLUMN_WIDTH_RELATIVE } type;
int min, max, width;
};
struct box;
/* parameters for <object> and related elements */
struct object_params {
char* data;
char* type;
char* codetype;
char* codebase;
char* classid;
struct plugin_params* params;
/* not a parameter, but stored here for convenience */
char* basehref;
char* filename;
int browser;
int plugin;
int browser_stream;
int plugin_stream;
unsigned int plugin_task;
};
struct plugin_params {
char* name;
char* value;
char* type;
char* valuetype;
struct plugin_params* next;
};
/** Node in box tree. All dimensions are in pixels. */
struct box {
/** Type of box. */
box_type type;
/** Style for this box. 0 for INLINE_CONTAINER and FLOAT_*. */
struct css_style * style;
/** Coordinate of left padding edge relative to parent box, or relative
* to ancestor that contains this box in float_children for FLOAT_. */
int x;
/** Coordinate of top padding edge, relative as for x. */
int y;
int width; /**< Width of content box (excluding padding etc.). */
int height; /**< Height of content box (excluding padding etc.). */
int margin[4]; /**< Margin: TOP, RIGHT, BOTTOM, LEFT. */
int padding[4]; /**< Padding: TOP, RIGHT, BOTTOM, LEFT. */
int border[4]; /**< Border width: TOP, RIGHT, BOTTOM, LEFT. */
/**< Width of box taking all line breaks (including margins etc.). */
int min_width;
int max_width; /**< Width that would be taken with no line breaks. */
char *text; /**< Text, or 0 if none. Unterminated. */
unsigned int length; /**< Length of text. */
/** Text is followed by a space. */
unsigned int space : 1;
/** This box is a continuation of the previous box (eg from line
* breaking). gadget, href, title, col and style are shared with the
* previous box, and must not be freed when this box is destroyed. */
unsigned int clone : 1;
/** style is shared with some other box, and must not be freed when
* this box is destroyed. */
unsigned int style_clone : 1;
char *href; /**< Link, or 0. */
char *title; /**< Title, or 0. */
unsigned int columns; /**< Number of columns for TABLE only. */
unsigned int rows; /**< Number of rows for TABLE only. */
unsigned int start_column; /**< Start column for TABLE_CELL only. */
struct box *next; /**< Next sibling box, or 0. */
struct box *prev; /**< Previous sibling box, or 0. */
struct box *children; /**< First child box, or 0. */
struct box *last; /**< Last child box, or 0. */
struct box *parent; /**< Parent box, or 0. */
/** First float child box, or 0. Float boxes are in the tree twice, in
* this list for the block box which defines the area for floats, and
* also in the standard tree given by children, next, prev, etc. */
struct box *float_children;
/** Next sibling float box. */
struct box *next_float;
struct column *col; /**< Table column data for TABLE only. */
struct font_data *font; /**< Font, or 0 if no text. */
/** Form control data, or 0 if not a form control. */
struct form_control* gadget;
char *usemap; /** (Image)map to use with this object, or 0 if none */
/** Object in this box (usually an image), or 0 if none. */
struct content* object;
/** Parameters for the object, or 0. */
struct object_params *object_params;
/** State of object, or 0. */
void *object_state;
};
#define UNKNOWN_WIDTH INT_MAX
#define UNKNOWN_MAX_WIDTH INT_MAX
void xml_to_box(xmlNode *n, struct content *c);
void box_dump(struct box * box, unsigned int depth);
struct box * box_create(struct css_style * style,
char *href, char *title, pool box_pool);
void box_add_child(struct box * parent, struct box * child);
void box_insert_sibling(struct box *box, struct box *new_box);
void box_free(struct box *box);
void box_coords(struct box *box, int *x, int *y);
#endif