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static char const rcsid[] = "@(#) $Id: htmllayout.c,v 1.1.1.1 2002/06/20 21:19:33 joye Exp $";
/*
** This file contains the code used to position elements of the
** HTML file on the screen.
**
** Copyright (C) 1997-2000 D. Richard Hipp
**
** This library is free software; you can redistribute it and/or
** modify it under the terms of the GNU Library General Public
** License as published by the Free Software Foundation; either
** version 2 of the License, or (at your option) any later version.
**
** This library 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
** Library General Public License for more details.
**
** You should have received a copy of the GNU Library General Public
** License along with this library; if not, write to the
** Free Software Foundation, Inc., 59 Temple Place - Suite 330,
** Boston, MA 02111-1307, USA.
**
** Author contact information:
** drh@acm.org
** http://www.hwaci.com/drh/
*/
#include <tk.h>
#include <stdlib.h>
#include <string.h>
#include "htmllayout.h"
/*
** Push a new margin onto the given margin stack.
**
** If the "bottom" parameter is non-negative, then this margin will
** automatically expire for all text that is placed below the y-coordinate
** given by "bottom". This feature is used for <IMG ALIGN=left>
** and <IMG ALIGN=right> kinds of markup. It allows text to flow around
** an image.
**
** If "bottom" is negative, then the margin stays in force until
** it is explicitly canceled by a call to HtmlPopMargin().
*/
void HtmlPushMargin(
HtmlMargin **ppMargin, /* The margin stack onto which to push */
int indent, /* The indentation for the new margin */
int bottom, /* The margin expires at this Y coordinate */
int tag /* Markup that will cancel this margin */
){
HtmlMargin *pNew = HtmlAlloc( sizeof(HtmlMargin) );
pNew->pNext = *ppMargin;
if( pNew->pNext ){
pNew->indent = indent + pNew->pNext->indent;
TestPoint(0);
}else{
pNew->indent = indent;
TestPoint(0);
}
pNew->bottom = bottom;
pNew->tag = tag;
*ppMargin = pNew;
}
/*
** Pop one margin off of the given margin stack.
*/
static void HtmlPopOneMargin(HtmlMargin **ppMargin){
if( *ppMargin ){
HtmlMargin *pOld = *ppMargin;
*ppMargin = pOld->pNext;
HtmlFree(pOld);
}
}
/*
** Pop as many margins as necessary until the margin that was
** created with "tag" is popped off. Update the layout context
** to move past obsticles, if necessary.
**
** If there are some margins on the stack that contain non-negative
** bottom fields, that means there are some obsticles that we have
** not yet cleared. If these margins get popped off the stack,
** then we have to be careful to advance the pLC->bottom value so
** that the next line of text will clear the obsticle.
*/
static void HtmlPopMargin(
HtmlMargin **ppMargin, /* The margin stack to be popped */
int tag, /* The tag we want to pop */
HtmlLayoutContext *pLC /* Update this layout context */
){
int bottom = -1;
int oldTag;
HtmlMargin *pM;
for(pM=*ppMargin; pM && pM->tag!=tag; pM=pM->pNext){}
if( pM==0 ){
/* No matching margin is found. Do nothing. */
return;
}
while( (pM=*ppMargin)!=0 ){
if( pM->bottom>bottom ){
bottom = pM->bottom;
}
oldTag = pM->tag;
HtmlPopOneMargin(ppMargin);
if( oldTag==tag ) break;
}
if( pLC && pLC->bottom<bottom ){
pLC->headRoom += bottom - pLC->bottom;
pLC->bottom = bottom;
}
}
/*
** Pop all expired margins from the stack.
**
** An expired margin is one with a non-negative bottom parameter
** that is less than the value "y". "y" is the Y-coordinate of
** the top edge the next line of text to by positioned. What this
** function does is check to see if we have cleared any obsticles
** (an obsticle is an <IMG ALIGN=left> or <IMG ALIGN=right>) and
** expands the margins if we have.
*/
static void PopExpiredMargins(HtmlMargin **ppMarginStack, int y){
while( *ppMarginStack && (**ppMarginStack).bottom>=0 &&
(**ppMarginStack).bottom <= y ){
HtmlPopOneMargin(ppMarginStack);
}
}
/*
** Clear a margin stack to reclaim memory. This routine just blindly
** pops everything off the stack. Typically used when the screen is
** cleared or the widget is deleted, etc.
*/
void HtmlClearMarginStack(HtmlMargin **ppMargin){
while( *ppMargin ){
HtmlPopOneMargin(ppMargin);
}
}
/*
** This routine gathers as many tokens as will fit on one line.
**
** The candidate tokens begin with pStart and go thru the end of
** the list or to pEnd, whichever comes first. The first token
** at the start of the next line is returned. NULL is returned if
** we exhaust data.
**
** "width" is the maximum allowed width of the line. The actual
** width is returned in *actualWidth. The actual width does not
** include any trailing spaces. Sometimes the actual width will
** be greater than the maximum width. This will happen, for example,
** for text enclosed in <pre>..</pre> that has lines longer than
** the width of the page.
**
** If the list begins with text, at least one token is returned,
** even if that one token is longer than the allowed line length.
** But if the list begins with some kind of break markup (possibly
** preceded by white space) then the returned list may be empty.
**
** The "x" coordinates of all elements are set assuming that the line
** begins at 0. The calling routine should adjust these coordinates
** to position the line horizontally. (The FixLine() procedure does
** this.) Note that the "x" coordinate of <li> elements will be negative.
** Text within <dt>..</dt> might also have a negative "x" coordinate.
** But in no case will the x coordinate every be less than "minX".
*/
static HtmlElement *GetLine(
HtmlLayoutContext *pLC, /* The complete layout context. */
HtmlElement *pStart, /* First token on new line */
HtmlElement *pEnd, /* End of line. Might be NULL */
int width, /* How much space is on this line */
int minX, /* The minimum value of the X coordinate */
int *actualWidth /* Return space actually required */
){
int x; /* Current X coordinate */
int spaceWanted = 0; /* Add this much space before next token */
HtmlElement *p; /* For looping over tokens */
HtmlElement *lastBreak = 0; /* Last line-break opportunity */
int isEmpty = 1; /* True if link contains nothing */
int origin; /* Initial value of "x" */
*actualWidth = 0;
p = pStart;
while( p && p!=pEnd && (p->base.style.flags & STY_Invisible)!=0 ){
p = p->pNext;
}
if( p && p->base.style.flags & STY_DT ){
origin = -HTML_INDENT;
}else{
origin = 0;
}
x = origin;
if( x<minX ){ x = minX; }
if( p && p!=pEnd && p->base.type==Html_LI ){
p->li.x = x - HTML_INDENT/3;
if( p->li.x - (HTML_INDENT*2)/3<minX ){
x += minX - p->li.x + (HTML_INDENT*2)/3;
p->li.x = minX + (HTML_INDENT*2)/3;
}
isEmpty = 0;
*actualWidth = 1;
p = p->pNext;
while( p && (p->base.type==Html_Space || p->base.type==Html_P) ){
p = p->pNext;
}
}
for(; p && p!=pEnd; p=p->pNext){
if( p->base.style.flags & STY_Invisible ){
continue;
}
switch( p->base.type ){
case Html_Text:
p->text.x = x + spaceWanted;
if( (p->base.style.flags & STY_Preformatted) == 0 ){
if( lastBreak && x + spaceWanted + p->text.w > width ){
TestPoint(0);
return lastBreak;
}
}
TRACE(HtmlTrace_GetLine2, ("Place token %s at x=%d w=%d\n",
HtmlTokenName(p), p->text.x, p->text.w));
x += p->text.w + spaceWanted;
isEmpty = 0;
spaceWanted = 0;
break;
case Html_Space:
if( p->base.style.flags & STY_Preformatted ){
if( p->base.flags & HTML_NewLine ){
*actualWidth = x<=0 ? 1 : x;
TestPoint(0);
return p->pNext;
}
x += p->space.w * p->base.count;
TestPoint(0);
}else{
int w;
if( (p->base.style.flags & STY_NoBreak)==0 ){
lastBreak = p->pNext;
*actualWidth = x<=0 && !isEmpty ? 1 : x;
}
w = p->space.w;
if( spaceWanted < w && x>origin ){
spaceWanted = w;
}
}
break;
case Html_IMG:
switch( p->image.align ){
case IMAGE_ALIGN_Left:
case IMAGE_ALIGN_Right:
*actualWidth = x<=0 && !isEmpty ? 1 : x;
return p;
default:
break;
}
p->image.x = x + spaceWanted;
if( (p->base.style.flags & STY_Preformatted) == 0 ){
if( lastBreak && x + spaceWanted + p->image.w > width ){
TestPoint(0);
return lastBreak;
}
}
TRACE(HtmlTrace_GetLine2, ("Place in-line image %s at x=%d w=%d\n",
HtmlTokenName(p), p->image.x, p->image.w));
x += p->image.w + spaceWanted;
if( (p->base.style.flags & STY_NoBreak)==0 ){
lastBreak = p->pNext;
*actualWidth = x<=0 && !isEmpty ? 1 : x;
}
spaceWanted = 0;
isEmpty = 0;
break;
case Html_APPLET:
case Html_EMBED:
case Html_INPUT:
case Html_SELECT:
case Html_TEXTAREA:
p->input.x = x + spaceWanted + p->input.padLeft;
if( (p->base.style.flags & STY_Preformatted) == 0 ){
if( lastBreak && x + spaceWanted + p->input.w > width ){
TestPoint(0);
return lastBreak;
}
}
TRACE(HtmlTrace_GetLine2, ("Place token %s at x=%d w=%d\n",
HtmlTokenName(p), p->input.x, p->input.w));
x = p->input.x + p->input.w;
if( (p->base.style.flags & STY_NoBreak)==0 ){
lastBreak = p->pNext;
*actualWidth = x<=0 && !isEmpty ? 1 : x;
}
spaceWanted = 0;
isEmpty = 0;
break;
case Html_EndTEXTAREA:
if( p->ref.pOther ){
/* HtmlResetTextarea(pLC->htmlPtr, p->ref.pOther); */
}
break;
case Html_DD:
if( p->ref.pOther==0 ) break;
if( p->ref.pOther->list.compact==0 || x + spaceWanted >= 0 ){
*actualWidth = x<=0 && !isEmpty ? 1 : x;
return p;
}
x = 0;
spaceWanted = 0;
break;
case Html_WBR:
*actualWidth = x<=0 && !isEmpty ? 1 : x;
if( x + spaceWanted >= width ){
return p->pNext;
}else{
lastBreak = p->pNext;
}
break;
case Html_ADDRESS:
case Html_EndADDRESS:
case Html_BLOCKQUOTE:
case Html_EndBLOCKQUOTE:
case Html_BODY:
case Html_EndBODY:
case Html_BR:
case Html_CAPTION:
case Html_EndCAPTION:
case Html_CENTER:
case Html_EndCENTER:
case Html_EndDD:
case Html_DIV:
case Html_EndDIV:
case Html_DL:
case Html_EndDL:
case Html_DT:
case Html_H1:
case Html_EndH1:
case Html_H2:
case Html_EndH2:
case Html_H3:
case Html_EndH3:
case Html_H4:
case Html_EndH4:
case Html_H5:
case Html_EndH5:
case Html_H6:
case Html_EndH6:
case Html_EndHTML:
case Html_HR:
case Html_LI:
case Html_LISTING:
case Html_EndLISTING:
case Html_MENU:
case Html_EndMENU:
case Html_OL:
case Html_EndOL:
case Html_P:
case Html_EndP:
case Html_PRE:
case Html_EndPRE:
case Html_TABLE:
case Html_EndTABLE:
case Html_TD:
case Html_EndTD:
case Html_TH:
case Html_EndTH:
case Html_TR:
case Html_EndTR:
case Html_UL:
case Html_EndUL:
*actualWidth = x<=0 && !isEmpty ? 1 : x;
return p;
default:
break;
}
}
*actualWidth = x<=0 && !isEmpty ? 1 : x;
return p;
}
/*
** Set the y coordinate for every anchor in the given list
*/
static void FixAnchors(HtmlElement *p, HtmlElement *pEnd, int y){
while( p && p!=pEnd ){
if( p->base.type==Html_A ){
p->anchor.y = y;
}
p = p->pNext;
}
}
/*
** This routine computes the X and Y coordinates for all elements of
** a line that has been gathered using GetLine() above. It also figures
** the ascent and descent for in-line images.
**
** The value returned is the Y coordinate of the bottom edge of the
** new line. The X coordinates are computed by adding the left margin
** plus any extra space needed for centering or right-justification.
*/
static int FixLine(
HtmlElement *pStart, /* Start of tokens for this line */
HtmlElement *pEnd, /* First token past end of this line. Maybe NULL */
int bottom, /* Put the top of this line here */
int width, /* This is the space available to the line */
int actualWidth, /* This is the actual width needed by the line */
int leftMargin, /* The current left margin */
int *maxX /* Write maximum X coordinate of ink here */
){
int dx; /* Amount by which to increase all X coordinates */
int maxAscent; /* Maximum height above baseline */
int maxTextAscent; /* Maximum height above baseline for text */
int maxDescent; /* Maximum depth below baseline */
int ascent, descent; /* Computed ascent and descent for one element */
HtmlElement *p; /* For looping */
int y; /* Y coordinate of the baseline */
int dy2center; /* Distance from baseline to text font center */
int max = 0;
if( actualWidth>0 ){
for(p=pStart; p && p!=pEnd && p->base.type!=Html_Text; p=p->pNext){}
if( p==pEnd || p==0 ) p = pStart;
if( p->base.style.align == ALIGN_Center ){
dx = leftMargin + (width - actualWidth)/2;
}else if( p->base.style.align == ALIGN_Right ){
dx = leftMargin + (width - actualWidth);
}else{
dx = leftMargin;
}
if( dx<0 ) dx = 0;
maxAscent = maxTextAscent = 0;
for(p=pStart; p && p!=pEnd; p=p->pNext){
int ss;
if( p->base.style.flags & STY_Invisible ){
continue;
}
switch( p->base.type ){
case Html_Text:
p->text.x += dx;
max = p->text.x + p->text.w;
ss = p->base.style.subscript;
if( ss > 0 ){
int ascent = p->text.ascent;
int delta = (ascent + p->text.descent)*ss/2;
ascent += delta;
p->text.y = -delta;
if( ascent > maxAscent ){ TestPoint(0); maxAscent = ascent; }
if( ascent > maxTextAscent ){ TestPoint(0); maxTextAscent = ascent;}
}else if( ss < 0 ){
int descent = p->text.descent;
int delta = (descent + p->text.ascent)*(-ss)/2;
descent += delta;
p->text.y = delta;
}else{
p->text.y = 0;
if( p->text.ascent > maxAscent ){
maxAscent = p->text.ascent;
}
if( p->text.ascent > maxTextAscent ){
maxTextAscent = p->text.ascent;
}
}
break;
case Html_Space:
if( p->space.ascent > maxAscent ){
maxAscent = p->space.ascent;
}
break;
case Html_LI:
p->li.x += dx;
if( p->li.x > max ){
max = p->li.x;
}
break;
case Html_IMG:
p->image.x += dx;
max = p->image.x + p->image.w;
switch( p->image.align ){
case IMAGE_ALIGN_Middle:
p->image.descent = p->image.h/2;
p->image.ascent = p->image.h - p->image.descent;
if( p->image.ascent > maxAscent ){
maxAscent = p->image.ascent;
}
break;
case IMAGE_ALIGN_AbsMiddle:
dy2center = (p->image.textDescent - p->image.textAscent)/2;
p->image.descent = p->image.h/2 + dy2center;
p->image.ascent = p->image.h - p->image.descent;
if( p->image.ascent > maxAscent ){
maxAscent = p->image.ascent;
}
break;
case IMAGE_ALIGN_Bottom:
p->image.descent = 0;
p->image.ascent = p->image.h;
if( p->image.ascent > maxAscent ){
maxAscent = p->image.ascent;
}
break;
case IMAGE_ALIGN_AbsBottom:
p->image.descent = p->image.textDescent;
p->image.ascent = p->image.h - p->image.descent;
if( p->image.ascent > maxAscent ){
maxAscent = p->image.ascent;
}
break;
default:
TestPoint(0);
break;
}
break;
case Html_TEXTAREA:
case Html_INPUT:
case Html_SELECT:
case Html_EMBED:
case Html_APPLET:
p->input.x += dx;
max = p->input.x + p->input.w;
dy2center = (p->input.textDescent - p->input.textAscent)/2;
p->input.y = dy2center - p->input.h/2;
ascent = -p->input.y;
if( ascent > maxAscent ){
maxAscent = ascent;
}
break;
default:
/* Shouldn't happen */
break;
}
}
*maxX = max;
y = maxAscent + bottom;
maxDescent = 0;
for(p=pStart; p && p!=pEnd; p=p->pNext){
if( p->base.style.flags & STY_Invisible ){
TestPoint(0);
continue;
}
switch( p->base.type ){
case Html_Text:
p->text.y += y;
if( p->text.descent > maxDescent ){
maxDescent = p->text.descent;
}
break;
case Html_LI:
p->li.y = y;
if( p->li.descent > maxDescent ){
maxDescent = p->li.descent;
}
break;
case Html_IMG:
p->image.y = y;
switch( p->image.align ){
case IMAGE_ALIGN_Top:
p->image.ascent = maxAscent;
p->image.descent = p->image.h - maxAscent;
TestPoint(0);
break;
case IMAGE_ALIGN_TextTop:
p->image.ascent = maxTextAscent;
p->image.descent = p->image.h - maxTextAscent;
TestPoint(0);
break;
default:
TestPoint(0);
break;
}
if( p->image.descent > maxDescent ){
maxDescent = p->image.descent;
}
break;
case Html_INPUT:
case Html_SELECT:
case Html_TEXTAREA:
case Html_APPLET:
case Html_EMBED:
descent = p->input.y + p->input.h;
p->input.y += y;
if( descent > maxDescent ){
maxDescent = descent;
}
break;
default:
/* Shouldn't happen */
break;
}
}
TRACE(HtmlTrace_FixLine,
("Setting baseline to %d. bottom=%d ascent=%d descent=%d dx=%d\n",
y, bottom, maxAscent, maxDescent, dx));
}else{
maxDescent = 0;
y = bottom;
}
return y + maxDescent;
}
/*
** Increase the headroom to create a paragraph break at the current token
*/
static void Paragraph(
HtmlLayoutContext *pLC,
HtmlElement *p
){
int headroom;
if( p==0 ){ TestPoint(0); return; }
if( p->base.type==Html_Text ){
headroom = p->text.ascent + p->text.descent;
TestPoint(0);
}else if( p->pNext && p->pNext->base.type==Html_Text ){
headroom = p->pNext->text.ascent + p->pNext->text.descent;
TestPoint(0);
}else{
Tk_FontMetrics fontMetrics;
Tk_Font font;
font = HtmlGetFont(pLC->htmlPtr, p->base.style.font);
if( font==0 ) return;
Tk_GetFontMetrics(font, &fontMetrics);
headroom = fontMetrics.descent + fontMetrics.ascent;
TestPoint(0);
}
if( pLC->headRoom < headroom && pLC->bottom > pLC->top ){
pLC->headRoom = headroom;
}
}
/*
** Compute the current margins for layout. Three values are returned:
**
** *pY The top edge of the area in which we can put ink. This
** takes into account any requested headroom.
**
** *pX The left edge of the inkable area. The takes into account
** any margin requests active at vertical position specified
** in pLC->bottom.
**
** *pW The width of the inkable area. This takes into account
** an margin requests that are active at the vertical position
** pLC->bottom.
**
*/
void HtmlComputeMargins(
HtmlLayoutContext *pLC, /* The current layout context */
int *pX, /* Put the left edge here */
int *pY, /* Put the top edge here */
int *pW /* Put the width here */
){
int x, y, w;
y = pLC->bottom + pLC->headRoom;
PopExpiredMargins(&pLC->leftMargin, pLC->bottom);
PopExpiredMargins(&pLC->rightMargin, pLC->bottom);
w = pLC->pageWidth - pLC->right;
if( pLC->leftMargin ){
x = pLC->leftMargin->indent + pLC->left;
TestPoint(0);
}else{
x = pLC->left;
TestPoint(0);
}
w -= x;
if( pLC->rightMargin ){
w -= pLC->rightMargin->indent;
TestPoint(0);
}else{
TestPoint(0);
}
*pX = x;
*pY = y;
*pW = w;
}
/*
** Clear a wrap-around obstacle. The second option determines the
** precise behavior.
**
** CLEAR_Left Clear all obstacles on the left.
**
** CLEAR_Right Clear all obstacles on the right.
**
** CLEAR_Both Clear all obstacles on both sides.
**
** CLEAR_First Clear only the first obsticle on either side.
*/
#define CLEAR_Left 0
#define CLEAR_Right 1
#define CLEAR_Both 2
#define CLEAR_First 3
static void ClearObstacle(HtmlLayoutContext *pLC, int mode){
int newBottom = pLC->bottom;
PopExpiredMargins(&pLC->leftMargin, pLC->bottom);
PopExpiredMargins(&pLC->rightMargin, pLC->bottom);
switch( mode ){
case CLEAR_Both:
ClearObstacle(pLC,CLEAR_Left);
ClearObstacle(pLC,CLEAR_Right);
TestPoint(0);
break;
case CLEAR_Left:
while( pLC->leftMargin && pLC->leftMargin->bottom>=0 ){
newBottom = pLC->leftMargin->bottom;
HtmlPopOneMargin(&pLC->leftMargin);
TestPoint(0);
}
if( newBottom > pLC->bottom + pLC->headRoom ){
pLC->headRoom = 0;
TestPoint(0);
}else{
pLC->headRoom = newBottom - pLC->bottom;
TestPoint(0);
}
pLC->bottom = newBottom;
PopExpiredMargins(&pLC->rightMargin, pLC->bottom);
break;
case CLEAR_Right:
while( pLC->rightMargin && pLC->rightMargin->bottom>=0 ){
newBottom = pLC->rightMargin->bottom;
HtmlPopOneMargin(&pLC->rightMargin);
TestPoint(0);
}
if( newBottom > pLC->bottom + pLC->headRoom ){
pLC->headRoom = 0;
TestPoint(0);
}else{
pLC->headRoom = newBottom - pLC->bottom;
TestPoint(0);
}
pLC->bottom = newBottom;
PopExpiredMargins(&pLC->leftMargin, pLC->bottom);
break;
case CLEAR_First:
if( pLC->leftMargin && pLC->leftMargin->bottom>=0 ){
if( pLC->rightMargin
&& pLC->rightMargin->bottom < pLC->leftMargin->bottom
){
newBottom = pLC->rightMargin->bottom;
HtmlPopOneMargin(&pLC->rightMargin);
TestPoint(0);
}else{
newBottom = pLC->leftMargin->bottom;
HtmlPopOneMargin(&pLC->leftMargin);
TestPoint(0);
}
}else if( pLC->rightMargin && pLC->rightMargin->bottom>=0 ){
newBottom = pLC->rightMargin->bottom;
HtmlPopOneMargin(&pLC->rightMargin);
TestPoint(0);
}else{
TestPoint(0);
}
if( newBottom > pLC->bottom + pLC->headRoom ){
pLC->headRoom = 0;
TestPoint(0);
}else{
pLC->headRoom = newBottom - pLC->bottom;
TestPoint(0);
}
pLC->bottom = newBottom;
break;
}
}
/*
** Break markup is any kind of markup that might force a line-break. This
** routine handles a single element of break markup and returns a pointer
** to the first element past that markup. If p doesn't point to break
** markup, then p is returned. If p is an incomplete table (a <TABLE>
** that lacks a </TABLE>), then NULL is returned.
*/
static HtmlElement *DoBreakMarkup(
HtmlLayoutContext *pLC,
HtmlElement *p
){
HtmlElement *pNext = p->pNext;
char *z;
int x, y, w;
switch( p->base.type ){
case Html_A:
p->anchor.y = pLC->bottom;
TestPoint(0);
break;
case Html_BLOCKQUOTE:
HtmlPushMargin(&pLC->leftMargin, HTML_INDENT, -1, Html_EndBLOCKQUOTE);
HtmlPushMargin(&pLC->rightMargin, HTML_INDENT, -1, Html_EndBLOCKQUOTE);
Paragraph(pLC, p);
TestPoint(0);
break;
case Html_EndBLOCKQUOTE:
HtmlPopMargin(&pLC->leftMargin, Html_EndBLOCKQUOTE, pLC);
HtmlPopMargin(&pLC->rightMargin, Html_EndBLOCKQUOTE, pLC);
Paragraph(pLC, p);
TestPoint(0);
break;
case Html_IMG:
switch( p->image.align ){
case IMAGE_ALIGN_Left:
HtmlComputeMargins(pLC, &x, &y, &w);
p->image.x = x;
p->image.y = y;
p->image.ascent = 0;
p->image.descent = p->image.h;
HtmlPushMargin(&pLC->leftMargin, p->image.w + 2, y + p->image.h, 0);
SETMAX( pLC->maxY, y + p->image.h );
SETMAX( pLC->maxX, x + p->image.w );
break;
case IMAGE_ALIGN_Right:
HtmlComputeMargins(pLC, &x, &y, &w);
p->image.x = x + w - p->image.w;
p->image.y = y;
p->image.ascent = 0;
p->image.descent = p->image.h;
HtmlPushMargin(&pLC->rightMargin, p->image.w + 2, y + p->image.h, 0);
SETMAX( pLC->maxY, y + p->image.h );
SETMAX( pLC->maxX, x + p->image.w );
break;
default:
TestPoint(0);
pNext = p;
break;
}
break;
case Html_PRE:
/* Skip space tokens thru the next newline. */
while( pNext->base.type==Html_Space ){
HtmlElement *pThis = pNext;
pNext = pNext->pNext;
if( pThis->base.flags & HTML_NewLine ){ TestPoint(0); break; }
}
Paragraph(pLC,p);
break;
case Html_UL:
case Html_MENU:
case Html_DIR:
case Html_OL:
if( p->list.compact==0 ){
Paragraph(pLC,p);
}
HtmlPushMargin(&pLC->leftMargin, HTML_INDENT, -1, p->base.type+1);
break;
case Html_EndOL:
case Html_EndUL:
case Html_EndMENU:
case Html_EndDIR:
if( p->ref.pOther ){
HtmlPopMargin(&pLC->leftMargin, p->base.type, pLC);
if( !p->ref.pOther->list.compact ){
Paragraph(pLC,p);
}
}
break;
case Html_DL:
Paragraph(pLC,p);
HtmlPushMargin(&pLC->leftMargin, HTML_INDENT, -1, Html_EndDL);
TestPoint(0);
break;
case Html_EndDL:
HtmlPopMargin(&pLC->leftMargin, Html_EndDL, pLC);
Paragraph(pLC,p);
TestPoint(0);
break;
case Html_HR: {
int zl, wd;
p->hr.is3D = HtmlMarkupArg(p, "noshade", 0)==0;
z = HtmlMarkupArg(p, "size", 0);
if( z ){
p->hr.h = atoi(z);
}else{
p->hr.h = 0;
}
if( p->hr.h<1 ){
int relief = pLC->htmlPtr->ruleRelief;
if( p->hr.is3D
&& (relief==TK_RELIEF_SUNKEN || relief==TK_RELIEF_RAISED) ){
p->hr.h = 3;
}else{
p->hr.h = 2;
}
}
HtmlComputeMargins(pLC, &x, &y, &w);
p->hr.y = y;
y += p->hr.h + 1;
p->hr.x = x;
z = HtmlMarkupArg(p, "width", "100%");
zl = strlen(z);
if( zl>0 && z[zl-1]=='%' ){
wd = (atoi(z)*w)/100;
}else{
wd = atoi(z);
}
if( wd>w ) wd = w;
p->hr.w = wd;
switch( p->base.style.align ){
case ALIGN_Center:
case ALIGN_None:
p->hr.x += (w - wd)/2;
TestPoint(0);
break;
case ALIGN_Right:
p->hr.x += (w - wd);
TestPoint(0);
break;
default:
TestPoint(0);
break;
}
SETMAX( pLC->maxY, y);
SETMAX( pLC->maxX, wd + p->hr.x );
pLC->bottom = y;
pLC->headRoom = 0;
break;
}
case Html_ADDRESS:
case Html_EndADDRESS:
case Html_CENTER:
case Html_EndCENTER:
case Html_DIV:
case Html_EndDIV:
case Html_H1:
case Html_EndH1:
case Html_H2:
case Html_EndH2:
case Html_H3:
case Html_EndH3:
case Html_H4:
case Html_EndH4:
case Html_H5:
case Html_EndH5:
case Html_H6:
case Html_EndH6:
case Html_P:
case Html_EndP:
case Html_EndPRE:
Paragraph(pLC, p);
TestPoint(0);
break;
case Html_TABLE:
pNext = HtmlTableLayout(pLC, p);
TestPoint(0);
break;
case Html_BR:
z = HtmlMarkupArg(p, "clear",0);
if( z ){
if( stricmp(z,"left")==0 ){
ClearObstacle(pLC, CLEAR_Left);
TestPoint(0);
}else if( stricmp(z,"right")==0 ){
ClearObstacle(pLC, CLEAR_Right);
TestPoint(0);
}else{
ClearObstacle(pLC, CLEAR_Both);
TestPoint(0);
}
}else{
TestPoint(0);
}
break;
/* All of the following tags need to be handed to the GetLine() routine */
case Html_Text:
case Html_Space:
case Html_LI:
case Html_INPUT:
case Html_SELECT:
case Html_TEXTAREA:
case Html_APPLET:
case Html_EMBED:
pNext = p;
TestPoint(0);
break;
default:
TestPoint(0);
break;
}
return pNext;
}
/*
** Return TRUE (non-zero) if we are currently wrapping text around
** one or more images.
*/
static int InWrapAround(HtmlLayoutContext *pLC){
if( pLC->leftMargin && pLC->leftMargin->bottom >= 0 ){
TestPoint(0);
return 1;
}
if( pLC->rightMargin && pLC->rightMargin->bottom >= 0 ){
TestPoint(0);
return 1;
}
TestPoint(0);
return 0;
}
/*
** Move past obsticles until a linewidth of reqWidth is obtained,
** or until all obsticles are cleared.
*/
void HtmlWidenLine(
HtmlLayoutContext *pLC, /* The layout context */
int reqWidth, /* Requested line width */
int *pX, int *pY, int *pW /* The margins. See HtmllComputeMargins() */
){
HtmlComputeMargins(pLC, pX, pY, pW);
if( *pW<reqWidth && InWrapAround(pLC) ){
ClearObstacle(pLC, CLEAR_First);
HtmlComputeMargins(pLC, pX, pY, pW);
}
}
#ifdef TABLE_TRIM_BLANK
int HtmlLineWasBlank = 0;
#endif /* TABLE_TRIM_BLANK */
/*
** Do as much layout as possible on the block of text defined by
** the HtmlLayoutContext.
*/
void HtmlLayoutBlock(HtmlLayoutContext *pLC){
HtmlElement *p, *pNext;
for(p=pLC->pStart; p && p!=pLC->pEnd; p=pNext){
int lineWidth;
int actualWidth;
int y = 0;
int leftMargin;
int maxX = 0;
/* Do as much break markup as we can. */
while( p && p!=pLC->pEnd ){
HtmlLock(pLC->htmlPtr);
pNext = DoBreakMarkup(pLC, p);
if( HtmlUnlock(pLC->htmlPtr) ) return;
if( pNext==p ){ TestPoint(0); break; }
if( pNext ){
TRACE(HtmlTrace_BreakMarkup,
("Processed token %s as break markup\n", HtmlTokenName(p)));
pLC->pStart = p;
}
p = pNext;
TestPoint(0);
}
if( p==0 || p==pLC->pEnd ){ TestPoint(0); break; }
#ifdef TABLE_TRIM_BLANK
HtmlLineWasBlank = 0;
#endif /* TABLE_TRIM_BLANK */
/* We might try several times to layout a single line... */
while( 1 ){
/* Compute margins */
HtmlComputeMargins(pLC, &leftMargin, &y, &lineWidth);
/* Layout a single line of text */
pNext = GetLine(pLC, p, pLC->pEnd, lineWidth, pLC->left-leftMargin,
&actualWidth);
TRACE(HtmlTrace_GetLine,
("GetLine page=%d left=%d right=%d available=%d used=%d\n",
pLC->pageWidth, pLC->left, pLC->right, lineWidth, actualWidth));
FixAnchors(p,pNext,pLC->bottom);
/* Move down and repeat the layout if we exceeded the available
** line length and it is possible to increase the line length by
** moving past some obsticle.
*/
if( actualWidth > lineWidth && InWrapAround(pLC) ){
ClearObstacle(pLC, CLEAR_First);
TestPoint(0);
continue;
}
/* Lock the line into place and exit the loop */
y = FixLine(p, pNext, y, lineWidth, actualWidth, leftMargin, &maxX);
TestPoint(0);
break;
}
#ifdef TABLE_TRIM_BLANK
/*
* I noticed that a newline following break markup would result
* in a blank line being drawn. So if an "empty" line was found
* I subtract any whitespace caused by break markup.
*/
if (actualWidth <= 0)
{
HtmlLineWasBlank = 1;
}
#endif /* TABLE_TRIM_BLANK */
/* If a line was completed, advance to the next line */
if( pNext && actualWidth>0 && y > pLC->bottom ){
pLC->bottom = y;
pLC->headRoom = 0;
pLC->pStart = pNext;
}
if( y > pLC->maxY ){
pLC->maxY = y;
}
if( maxX > pLC->maxX ){
pLC->maxX = maxX;
}
}
}
/*
** Advance the layout as far as possible
*/
void HtmlLayout(HtmlWidget *htmlPtr){
HtmlLayoutContext *pLC;
int btm;
if( htmlPtr->pFirst==0 ) return;
HtmlLock(htmlPtr);
HtmlSizer(htmlPtr);
if( HtmlUnlock(htmlPtr) ) return;
pLC = &htmlPtr->layoutContext;
pLC->htmlPtr = htmlPtr;
pLC->pageWidth = htmlPtr->realWidth - 2*(htmlPtr->inset + htmlPtr->padx);
pLC->left = 0;
pLC->right = 0;
pLC->pStart = htmlPtr->nextPlaced;
if( pLC->pStart==0 ){
pLC->pStart = htmlPtr->pFirst;
}
if( pLC->pStart ){
pLC->maxX = htmlPtr->maxX;
pLC->maxY = htmlPtr->maxY;
btm = pLC->bottom;
HtmlLock(htmlPtr);
HtmlLayoutBlock(pLC);
if( HtmlUnlock(htmlPtr) ) return;
htmlPtr->maxX = pLC->maxX;
htmlPtr->maxY = pLC->maxY;
htmlPtr->nextPlaced = pLC->pStart;
htmlPtr->flags |= HSCROLL | VSCROLL;
HtmlRedrawText(htmlPtr, btm);
}
}
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