archie/tk3.6/tkTextDisp.c

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2024-05-27 16:13:40 +02:00
/*
* tkTextDisp.c --
*
* This module provides facilities to display text widgets. It is
* the only place where information is kept about the screen layout
* of text widgets.
*
* Copyright (c) 1992-1993 The Regents of the University of California.
* All rights reserved.
*
* Permission is hereby granted, without written agreement and without
* license or royalty fees, to use, copy, modify, and distribute this
* software and its documentation for any purpose, provided that the
* above copyright notice and the following two paragraphs appear in
* all copies of this software.
*
* IN NO EVENT SHALL THE UNIVERSITY OF CALIFORNIA BE LIABLE TO ANY PARTY FOR
* DIRECT, INDIRECT, SPECIAL, INCIDENTAL, OR CONSEQUENTIAL DAMAGES ARISING OUT
* OF THE USE OF THIS SOFTWARE AND ITS DOCUMENTATION, EVEN IF THE UNIVERSITY OF
* CALIFORNIA HAS BEEN ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*
* THE UNIVERSITY OF CALIFORNIA SPECIFICALLY DISCLAIMS ANY WARRANTIES,
* INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY
* AND FITNESS FOR A PARTICULAR PURPOSE. THE SOFTWARE PROVIDED HEREUNDER IS
* ON AN "AS IS" BASIS, AND THE UNIVERSITY OF CALIFORNIA HAS NO OBLIGATION TO
* PROVIDE MAINTENANCE, SUPPORT, UPDATES, ENHANCEMENTS, OR MODIFICATIONS.
*/
#ifndef lint
static char rcsid[] = "$Header: /user6/ouster/wish/RCS/tkTextDisp.c,v 1.38 93/11/01 15:05:54 ouster Exp $ SPRITE (Berkeley)";
#endif
#include "tkConfig.h"
#include "tkInt.h"
#include "tkText.h"
/*
* The following structure describes how to display a range of characters.
* The information is generated by scanning all of the tags associated
* with the characters and combining that with default information for
* the overall widget. These structures form the hash keys for
* dInfoPtr->styleTable.
*/
typedef struct StyleValues {
Tk_3DBorder border; /* Used for drawing background under text.
* NULL means use widget background. */
int borderWidth; /* Width of 3-D border for background. */
int relief; /* 3-D relief for background. */
Pixmap bgStipple; /* Stipple bitmap for background. None
* means draw solid. */
XColor *fgColor; /* Foreground color for text. */
XFontStruct *fontPtr; /* Font for displaying text. */
Pixmap fgStipple; /* Stipple bitmap for text and other
* foreground stuff. None means draw
* solid.*/
int underline; /* Non-zero means draw underline underneath
* text. */
} StyleValues;
/*
* The following structure extends the StyleValues structure above with
* graphics contexts used to actually draw the characters. The entries
* in dInfoPtr->styleTable point to structures of this type.
*/
typedef struct Style {
int refCount; /* Number of times this structure is
* referenced in Chunks. */
GC bgGC; /* Graphics context for background. None
* unless background is stippled. */
GC fgGC; /* Graphics context for foreground. */
StyleValues *sValuePtr; /* Raw information from which GCs were
* derived. */
Tcl_HashEntry *hPtr; /* Pointer to entry in styleTable. Used
* to delete entry. */
} Style;
/*
* The following structure describes a range of characters, all on the
* same line of the display (which also means the same line of the text
* widget) and all having the same display attributes.
*/
typedef struct Chunk {
char *text; /* Characters to display. */
int numChars; /* Number of characters to display. */
Style *stylePtr; /* Style information used to display
* characters. */
int x; /* X-coordinate of pixel at which to display
* the characters. */
struct Chunk *nextPtr; /* Next in list of all chunks displayed on the
* same display line. */
} Chunk;
/*
* The following structure describes one line of the display, which may
* be either part or all of one line of the text.
*/
typedef struct DLine {
TkTextLine *linePtr; /* Pointer to structure in B-tree that
* contains characters displayed in this
* line. */
int y; /* Y-position at which line is supposed to
* be drawn (topmost pixel of rectangular
* area occupied by line). */
int oldY; /* Y-position at which line currently
* appears on display. -1 means line isn't
* currently visible on display. This is
* used to move lines by scrolling rather
* than re-drawing. */
int height; /* Height of line, in pixels. */
int baseline; /* Offset of text baseline from y. */
Chunk *chunkPtr; /* Pointer to first chunk in list of all
* of those that are displayed on this
* line of the screen. */
struct DLine *nextPtr; /* Next in list of all display lines for
* this window. The list is sorted in
* order from top to bottom. Note: the
* next DLine doesn't always correspond
* to the next line of text: (a) can have
* multiple DLines for one text line, and
* (b) can have gaps where DLine's have been
* deleted because they're out of date. */
} DLine;
/*
* Overall display information for a text widget:
*/
typedef struct DInfo {
Tcl_HashTable styleTable; /* Hash table that maps from StyleValues to
* Styles for this widget. */
DLine *dLinePtr; /* First in list of all display lines for
* this widget, in order from top to bottom. */
GC copyGC; /* Graphics context for copying from off-
* screen pixmaps onto screen. */
GC scrollGC; /* Graphics context for copying from one place
* in the window to another (scrolling):
* differs from copyGC in that we need to get
* GraphicsExpose events. */
int x; /* First x-coordinate that may be used for
* actually displaying line information.
* Leaves space for border, etc. */
int y; /* First y-coordinate that may be used for
* actually displaying line information.
* Leaves space for border, etc. */
int maxX; /* First x-coordinate to right of available
* space for displaying lines. */
int maxY; /* First y-coordinate below available
* space for displaying lines. */
int topOfEof; /* Top-most pixel (lowest y-value) that has
* been drawn in the appropriate fashion for
* the portion of the window after the last
* line of the text. This field is used to
* figure out when to redraw part or all of
* the eof field. */
int flags; /* Various flag values: see below for
* definitions. */
} DInfo;
/*
* Flag values for DInfo structures:
*
* DINFO_OUT_OF_DATE: Non-zero means that the DLine structures
* for this window are partially or completely
* out of date and need to be recomputed.
* REDRAW_PENDING: Means that a when-idle handler has been
* scheduled to update the display.
* REDRAW_BORDERS: Means window border or pad area has
* potentially been damaged and must be redrawn.
* REPICK_NEEDED: 1 means that the widget has been modified
* in a way that could change the current
* character (a different character might be
* under the mouse cursor now). Need to
* recompute the current character before
* the next redisplay.
*/
#define DINFO_OUT_OF_DATE 1
#define REDRAW_PENDING 2
#define REDRAW_BORDERS 4
#define REPICK_NEEDED 8
/*
* Structures of the type defined below are used to keep track of
* tags while scanning through the text to create DLine structures.
*/
typedef struct TagInfo {
int numTags; /* Number of tags currently active (the first
* entries at *tagPtr). */
int arraySize; /* Total number of entries at *tagPtr. We
* over-allocate the array to avoid continual
* reallocations. */
TkTextTag **tagPtrs; /* Pointer to array of pointers to active tags.
* Array has space for arraySize tags, and
* the first numTags are slots identify the
* active tags. Malloc'ed (but may be NULL). */
TkTextSearch search; /* Used to scan for tag transitions. Current
* state identifies next tag transition. */
} TagInfo;
/*
* The following counters keep statistics about redisplay that can be
* checked to see how clever this code is at reducing redisplays.
*/
static int numRedisplays; /* Number of calls to DisplayText. */
static int linesRedrawn; /* Number of calls to DisplayDLine. */
static int numCopies; /* Number of calls to XCopyArea to copy part
* of the screen. */
static int damagedCopies; /* Number of times that XCopyAreas didn't
* completely work because some of the source
* information was damaged. */
/*
* Forward declarations for procedures defined later in this file:
*/
static void ComputeStyleValues _ANSI_ARGS_((TkText *textPtr,
int numTags, TkTextTag **tagPtr,
StyleValues *sValuePtr));
static void DisplayDLine _ANSI_ARGS_((TkText *textPtr,
DLine *dlPtr, Pixmap pixmap));
static void DisplayText _ANSI_ARGS_((ClientData clientData));
static DLine * FindDLine _ANSI_ARGS_((DLine *dlPtr, int line));
static void FreeDLines _ANSI_ARGS_((TkText *textPtr,
DLine *firstPtr, DLine *lastPtr, int unlink));
static void FreeStyle _ANSI_ARGS_((TkText *textPtr,
Style *stylePtr));
static Style * GetStyle _ANSI_ARGS_((TkText *textPtr,
StyleValues *sValuePtr));
static DLine * LayoutLine _ANSI_ARGS_((TkText *textPtr, int line,
TkTextLine *linePtr, TagInfo *tInfoPtr));
static void ToggleTag _ANSI_ARGS_((TagInfo *tInfoPtr,
TkTextTag *tagPtr));
static void UpdateDisplayInfo _ANSI_ARGS_((TkText *textPtr));
/*
*----------------------------------------------------------------------
*
* TkTextCreateDInfo --
*
* This procedure is called when a new text widget is created.
* Its job is to set up display-related information for the widget.
*
* Results:
* None.
*
* Side effects:
* A DInfo data structure is allocated and initialized and attached
* to textPtr.
*
*----------------------------------------------------------------------
*/
void
TkTextCreateDInfo(textPtr)
TkText *textPtr; /* Overall information for text widget. */
{
register DInfo *dInfoPtr;
XGCValues gcValues;
dInfoPtr = (DInfo *) ckalloc(sizeof(DInfo));
Tcl_InitHashTable(&dInfoPtr->styleTable, sizeof(StyleValues)/sizeof(int));
dInfoPtr->dLinePtr = NULL;
gcValues.graphics_exposures = False;
dInfoPtr->copyGC = Tk_GetGC(textPtr->tkwin, GCGraphicsExposures, &gcValues);
gcValues.graphics_exposures = True;
dInfoPtr->scrollGC = Tk_GetGC(textPtr->tkwin, GCGraphicsExposures,
&gcValues);
dInfoPtr->topOfEof = 0;
dInfoPtr->flags = DINFO_OUT_OF_DATE;
textPtr->dInfoPtr = dInfoPtr;
}
/*
*----------------------------------------------------------------------
*
* TkTextFreeDInfo --
*
* This procedure is called to free up all of the private display
* information kept by this file for a text widget.
*
* Results:
* None.
*
* Side effects:
* Lots of resources get freed.
*
*----------------------------------------------------------------------
*/
void
TkTextFreeDInfo(textPtr)
TkText *textPtr; /* Overall information for text widget. */
{
register DInfo *dInfoPtr = textPtr->dInfoPtr;
/*
* Be careful to free up styleTable *after* freeing up all the
* DLines, so that the hash table is still intact to free up the
* style-related information from the lines. Once the lines are
* all free then styleTable will be empty.
*/
FreeDLines(textPtr, dInfoPtr->dLinePtr, (DLine *) NULL, 1);
Tcl_DeleteHashTable(&dInfoPtr->styleTable);
Tk_FreeGC(textPtr->display, dInfoPtr->copyGC);
Tk_FreeGC(textPtr->display, dInfoPtr->scrollGC);
if (dInfoPtr->flags & REDRAW_PENDING) {
Tk_CancelIdleCall(DisplayText, (ClientData) textPtr);
}
ckfree((char *) dInfoPtr);
}
/*
*----------------------------------------------------------------------
*
* GetStyle --
*
* This procedure creates graphics contexts needed to display
* text in a particular style, determined by "sValuePtr". It
* attempts to share style information as much as possible.
*
* Results:
* The return value is a pointer to a Style structure that
* corresponds to *sValuePtr.
*
* Side effects:
* A new entry may be created in the style table for the widget.
*
*----------------------------------------------------------------------
*/
static Style *
GetStyle(textPtr, sValuePtr)
TkText *textPtr; /* Overall information about text widget. */
StyleValues *sValuePtr; /* Information about desired style. */
{
Style *stylePtr;
Tcl_HashEntry *hPtr;
int new;
XGCValues gcValues;
unsigned long mask;
/*
* Use an existing style if there's one around that matches.
*/
hPtr = Tcl_CreateHashEntry(&textPtr->dInfoPtr->styleTable,
(char *) sValuePtr, &new);
if (!new) {
stylePtr = (Style *) Tcl_GetHashValue(hPtr);
stylePtr->refCount++;
return stylePtr;
}
/*
* No existing style matched. Make a new one.
*/
stylePtr = (Style *) ckalloc(sizeof(Style));
stylePtr->refCount = 1;
if ((sValuePtr->border != NULL) && (sValuePtr->bgStipple != None)) {
gcValues.foreground = Tk_3DBorderColor(sValuePtr->border)->pixel;
gcValues.stipple = sValuePtr->bgStipple;
gcValues.fill_style = FillStippled;
stylePtr->bgGC = Tk_GetGC(textPtr->tkwin,
GCForeground|GCStipple|GCFillStyle, &gcValues);
} else {
stylePtr->bgGC = None;
}
mask = GCForeground|GCFont;
gcValues.foreground = sValuePtr->fgColor->pixel;
gcValues.font = sValuePtr->fontPtr->fid;
if (sValuePtr->fgStipple != None) {
gcValues.stipple = sValuePtr->fgStipple;
gcValues.fill_style = FillStippled;
mask |= GCStipple|GCFillStyle;
}
stylePtr->fgGC = Tk_GetGC(textPtr->tkwin, mask, &gcValues);
stylePtr->sValuePtr = (StyleValues *)
Tcl_GetHashKey(&textPtr->dInfoPtr->styleTable, hPtr);
stylePtr->hPtr = hPtr;
Tcl_SetHashValue(hPtr, stylePtr);
return stylePtr;
}
/*
*----------------------------------------------------------------------
*
* FreeStyle --
*
* This procedure is called when a Style structure is no longer
* needed. It decrements the reference count and frees up the
* space for the style structure if the reference count is 0.
*
* Results:
* None.
*
* Side effects:
* The storage and other resources associated with the style
* are freed up if no-one's still using it.
*
*----------------------------------------------------------------------
*/
static void
FreeStyle(textPtr, stylePtr)
TkText *textPtr; /* Information about overall widget. */
register Style *stylePtr; /* Information about style to be freed. */
{
stylePtr->refCount--;
if (stylePtr->refCount == 0) {
if (stylePtr->bgGC != None) {
Tk_FreeGC(textPtr->display, stylePtr->bgGC);
}
Tk_FreeGC(textPtr->display, stylePtr->fgGC);
Tcl_DeleteHashEntry(stylePtr->hPtr);
ckfree((char *) stylePtr);
}
}
/*
*----------------------------------------------------------------------
*
* ComputeStyleValues --
*
* Given a list of tags that apply at a particular point, compute
* the StyleValues that correspond to that set of tags.
*
* Results:
* All of the fields of *sValuePtr get filled in to hold the
* appropriate display information for the given set of tags
* in the given widget.
*
* Side effects:
* None.
*
*----------------------------------------------------------------------
*/
static void
ComputeStyleValues(textPtr, numTags, tagPtrPtr, sValuePtr)
TkText *textPtr; /* Overall information for widget. */
int numTags; /* Number of tags at *tagPtr. */
register TkTextTag **tagPtrPtr; /* Pointer to array of tag pointers. */
register StyleValues *sValuePtr; /* Pointer to structure to fill in. */
{
register TkTextTag *tagPtr;
/*
* The variables below keep track of the highest-priority specification
* that has occurred for each of the various fields of the StyleValues.
*/
int borderPrio, bgStipplePrio;
int fgPrio, fontPrio, fgStipplePrio;
borderPrio = bgStipplePrio = -1;
fgPrio = fontPrio = fgStipplePrio = -1;
memset((VOID *) sValuePtr, 0, sizeof(StyleValues));
sValuePtr->fgColor = textPtr->fgColor;
sValuePtr->fontPtr = textPtr->fontPtr;
/*
* Scan through all of the tags, updating the StyleValues to hold
* the highest-priority information.
*/
for ( ; numTags > 0; tagPtrPtr++, numTags--) {
tagPtr = *tagPtrPtr;
if ((tagPtr->border != NULL) && (tagPtr->priority > borderPrio)) {
sValuePtr->border = tagPtr->border;
sValuePtr->borderWidth = tagPtr->borderWidth;
sValuePtr->relief = tagPtr->relief;
borderPrio = tagPtr->priority;
}
if ((tagPtr->bgStipple != None)
&& (tagPtr->priority > bgStipplePrio)) {
sValuePtr->bgStipple = tagPtr->bgStipple;
bgStipplePrio = tagPtr->priority;
}
if ((tagPtr->fgColor != None) && (tagPtr->priority > fgPrio)) {
sValuePtr->fgColor = tagPtr->fgColor;
fgPrio = tagPtr->priority;
}
if ((tagPtr->fontPtr != None) && (tagPtr->priority > fontPrio)) {
sValuePtr->fontPtr = tagPtr->fontPtr;
fontPrio = tagPtr->priority;
}
if ((tagPtr->fgStipple != None)
&& (tagPtr->priority > fgStipplePrio)) {
sValuePtr->fgStipple = tagPtr->fgStipple;
fgStipplePrio = tagPtr->priority;
}
if (tagPtr->underline) {
sValuePtr->underline = 1;
}
}
}
/*
*----------------------------------------------------------------------
*
* LayoutLine --
*
* This procedure generates a linked list of one or more DLine
* structures, which describe how to display everything in one
* line of the text.
*
* Results:
* The return value is a pointer to one or more DLine structures
* linked into a linked list. The structures are completely filled
* in except for the y field, which the caller must supply. Also,
* the information at *tInfoPtr gets updated to refer to the state
* just after the last character of the line.
*
* Side effects:
* None.
*
*----------------------------------------------------------------------
*/
static DLine *
LayoutLine(textPtr, line, linePtr, tInfoPtr)
TkText *textPtr; /* Overall information about text widget. */
int line; /* Index of line to layout. */
TkTextLine *linePtr; /* Line to layout (corresponds to line). */
TagInfo *tInfoPtr; /* Information to help keep track of tags.
* Caller must have initialized to correspond
* to state just before start of line. */
{
DLine *firstLinePtr;
DLine *lastLinePtr = NULL; /* Initializations needed only to stop */
Chunk *lastChunkPtr = NULL; /* compiler warnings. */
register DLine *dlPtr;
register Chunk *chunkPtr;
StyleValues styleValues;
int ch, charsThatFit, ascent, descent, x, maxX;
firstLinePtr = NULL;
/*
* Each iteration of the loop below creates one DLine structure.
*/
ch = 0;
while (1) {
/*
* Create and initialize a new DLine structure.
*/
dlPtr = (DLine *) ckalloc(sizeof(DLine));
dlPtr->linePtr = linePtr;
dlPtr->y = 0;
dlPtr->oldY = -1;
dlPtr->chunkPtr = NULL;
dlPtr->nextPtr = NULL;
if (firstLinePtr == NULL) {
firstLinePtr = dlPtr;
} else {
lastLinePtr->nextPtr = dlPtr;
}
lastLinePtr = dlPtr;
/*
* Each iteration of the loop below creates one Chunk for the
* new display line. Be sure always to create at least one chunk.
*/
x = textPtr->dInfoPtr->x;
maxX = textPtr->dInfoPtr->maxX;
ascent = descent = 0;
do {
chunkPtr = (Chunk *) ckalloc(sizeof(Chunk));
chunkPtr->numChars = linePtr->numBytes - ch;
chunkPtr->text = linePtr->bytes + ch;
chunkPtr->x = x;
chunkPtr->nextPtr = NULL;
if (dlPtr->chunkPtr == NULL) {
dlPtr->chunkPtr = chunkPtr;
} else {
lastChunkPtr->nextPtr = chunkPtr;
}
lastChunkPtr = chunkPtr;
/*
* Update the tag array to include any tag transitions up
* through the current position, then find the next position
* with a transition on a tag that impacts the way things are
* displayed.
*/
while (1) {
int affectsDisplay;
TkTextTag *tagPtr;
if ((tInfoPtr->search.linePtr == NULL)
|| (tInfoPtr->search.line1 > line)) {
break;
}
tagPtr = tInfoPtr->search.tagPtr;
affectsDisplay = TK_TAG_AFFECTS_DISPLAY(tagPtr);
if ((tInfoPtr->search.line1 < line)
|| (tInfoPtr->search.ch1 <= ch)) {
if (affectsDisplay) {
ToggleTag(tInfoPtr, tagPtr);
}
} else {
if (affectsDisplay) {
chunkPtr->numChars = tInfoPtr->search.ch1 - ch;
break;
}
}
(void) TkBTreeNextTag(&tInfoPtr->search);
}
/*
* Create style information for this chunk.
*/
ComputeStyleValues(textPtr, tInfoPtr->numTags, tInfoPtr->tagPtrs,
&styleValues);
chunkPtr->stylePtr = GetStyle(textPtr, &styleValues);
/*
* See how many characters will fit on the line. If they don't
* all fit, then a number of compensations may have to be made.
*
* 1. Make sure that at least one character is displayed on
* each line.
* 2. In wrap mode "none", allow a partial character to be
* displayed at the end of an incomplete line.
* 3. In wrap mode "word", search back to find the last space
* character, and terminate the line just after that space
* character. This involves a couple of extra complexities:
* - the last space may be several chunks back; in this
* case, delete all the chunks that are after the
* space.
* - if no words fit at all, then use character-wrap for
* this DLine.
* - have to reinitialize the tag search information, since
* we may back up over tag toggles (they'll need to be
* reconsidered on the next DLine).
*/
charsThatFit = TkMeasureChars(styleValues.fontPtr,
chunkPtr->text, chunkPtr->numChars, chunkPtr->x,
maxX, 0, &x);
if ((charsThatFit < chunkPtr->numChars) || (x >= maxX)) {
x = maxX;
chunkPtr->numChars = charsThatFit;
ch += charsThatFit;
if (ch < (linePtr->numBytes - 1)) {
if ((charsThatFit == 0) && (chunkPtr == dlPtr->chunkPtr)) {
chunkPtr->numChars = 1;
ch++;
} else if (textPtr->wrapMode == tkTextWordUid) {
if (isspace(UCHAR(chunkPtr->text[charsThatFit]))) {
ch += 1; /* Include space on this line. */
} else {
register Chunk *chunkPtr2;
register char *p;
Chunk *spaceChunkPtr;
int count, space;
spaceChunkPtr = NULL;
space = 0;
for (chunkPtr2 = dlPtr->chunkPtr;
chunkPtr2 != NULL;
chunkPtr2 = chunkPtr2->nextPtr) {
for (count = chunkPtr2->numChars - 1,
p = chunkPtr2->text + count;
count >= 0; count--, p--) {
if (isspace(UCHAR(*p))) {
spaceChunkPtr = chunkPtr2;
space = count;
break;
}
}
}
if (spaceChunkPtr != NULL) {
spaceChunkPtr->numChars = space;
ch = (spaceChunkPtr->text + space + 1)
- linePtr->bytes;
if (chunkPtr != spaceChunkPtr) {
chunkPtr = spaceChunkPtr;
if (tInfoPtr->tagPtrs != NULL) {
ckfree((char *) tInfoPtr->tagPtrs);
}
tInfoPtr->tagPtrs = TkBTreeGetTags(
textPtr->tree, dlPtr->linePtr, ch,
&tInfoPtr->numTags);
TkBTreeStartSearch(textPtr->tree, line,
ch+1,
TkBTreeNumLines(textPtr->tree), 0,
(TkTextTag *) NULL,
&tInfoPtr->search);
(void) TkBTreeNextTag(&tInfoPtr->search);
tInfoPtr->arraySize = tInfoPtr->numTags;
while (chunkPtr->nextPtr != NULL) {
chunkPtr2 = chunkPtr->nextPtr;
chunkPtr->nextPtr = chunkPtr2->nextPtr;
FreeStyle(textPtr, chunkPtr2->stylePtr);
ckfree((char *) chunkPtr2);
}
}
}
}
} else if (textPtr->wrapMode == tkTextNoneUid) {
chunkPtr->numChars++;
ch++;
}
}
} else {
ch += chunkPtr->numChars;
}
/*
* Update height information for use later in computing
* line's overall height and baseline.
*/
if (styleValues.fontPtr->ascent > ascent) {
ascent = styleValues.fontPtr->ascent;
}
if (styleValues.fontPtr->descent > descent) {
descent = styleValues.fontPtr->descent;
}
} while (x < maxX);
dlPtr->height = ascent + descent;
dlPtr->baseline = ascent;
/*
* Quit when every character but the last character (the newline)
* has been accounted for. Also quit if the wrap mode is "none":
* this ignores all the characters that don't fit on the first
* line.
*/
if ((ch >= (linePtr->numBytes-1))
|| (textPtr->wrapMode == tkTextNoneUid)) {
break;
}
}
return firstLinePtr;
}
/*
*----------------------------------------------------------------------
*
* ToggleTag --
*
* Update information about tags to reflect a transition on a
* particular tag.
*
* Results:
* The array at *tInfoPtr is modified to include tagPtr if it
* didn't already or to exclude it if it used to include it.
* The array will be reallocated to a larger size if needed.
*
* Side effects:
* None.
*
*----------------------------------------------------------------------
*/
static void
ToggleTag(tInfoPtr, tagPtr)
register TagInfo *tInfoPtr; /* Tag information to be updated. */
TkTextTag *tagPtr; /* Tag to be toggled into or out of
* *tInfoPtr. */
{
register TkTextTag **tagPtrPtr;
int i;
for (i = tInfoPtr->numTags, tagPtrPtr = tInfoPtr->tagPtrs;
i > 0; i--, tagPtrPtr++) {
if (*tagPtrPtr == tagPtr) {
tInfoPtr->numTags--;
*tagPtrPtr = tInfoPtr->tagPtrs[tInfoPtr->numTags];
return;
}
}
/*
* Tag not currently in array. Grow the array if necessary, then
* add the tag to it.
*/
if (tInfoPtr->numTags == tInfoPtr->arraySize) {
TkTextTag **newPtrs;
newPtrs = (TkTextTag **) ckalloc((unsigned)
((tInfoPtr->arraySize+10) * sizeof(TkTextTag *)));
if (tInfoPtr->tagPtrs != NULL) {
memcpy((VOID *) newPtrs, (VOID *) tInfoPtr->tagPtrs,
tInfoPtr->arraySize * sizeof(TkTextTag *));
ckfree((char *) tInfoPtr->tagPtrs);
}
tInfoPtr->tagPtrs = newPtrs;
tInfoPtr->arraySize += 10;
}
tInfoPtr->tagPtrs[tInfoPtr->numTags] = tagPtr;
tInfoPtr->numTags++;
}
/*
*----------------------------------------------------------------------
*
* UpdateDisplayInfo --
*
* This procedure is invoked to recompute some or all of the
* DLine structures for a text widget. At the time it is called
* the DLine structures still left in the widget are guaranteed
* to be correct (except for their y-coordinates), but there may
* be missing structures (the DLine structures get removed as
* soon as they are potentially out-of-date).
*
* Results:
* None.
*
* Side effects:
* Upon return, the DLine information for textPtr correctly reflects
* the positions where characters will be displayed. However, this
* procedure doesn't actually bring the display up-to-date.
*
*----------------------------------------------------------------------
*/
static void
UpdateDisplayInfo(textPtr)
TkText *textPtr; /* Text widget to update. */
{
register DInfo *dInfoPtr = textPtr->dInfoPtr;
register DLine *dlPtr, *prevPtr, *dlPtr2;
TkTextLine *linePtr;
TagInfo tagInfo;
int line, y, maxY;
if (!(dInfoPtr->flags & DINFO_OUT_OF_DATE)) {
return;
}
dInfoPtr->flags &= ~DINFO_OUT_OF_DATE;
linePtr = textPtr->topLinePtr;
dlPtr = dInfoPtr->dLinePtr;
tagInfo.tagPtrs = TkBTreeGetTags(textPtr->tree, linePtr, 0,
&tagInfo.numTags);
tagInfo.arraySize = tagInfo.numTags;
/*
* Tricky point: initialize the tag search just *after* the first
* character in the line, since the tagInfo structure already has all
* the tags for the first character.
*/
line = TkBTreeLineIndex(linePtr);
TkBTreeStartSearch(textPtr->tree, line, 1, TkBTreeNumLines(textPtr->tree),
0, (TkTextTag *) NULL, &tagInfo.search);
TkBTreeNextTag(&tagInfo.search);
prevPtr = NULL;
y = dInfoPtr->y;
maxY = dInfoPtr->maxY;
while (linePtr != NULL) {
register DLine *newPtr;
/*
* See if the next DLine matches the next line we want to
* appear on the screen. If so then we can just use its
* information. If not then create new DLine structures
* for the desired line and insert them into the list.
*/
if ((dlPtr == NULL) || (dlPtr->linePtr != linePtr)) {
newPtr = LayoutLine(textPtr, line, linePtr, &tagInfo);
if (prevPtr == NULL) {
dInfoPtr->dLinePtr = newPtr;
} else {
prevPtr->nextPtr = newPtr;
}
for (dlPtr2 = newPtr; dlPtr2->nextPtr != NULL;
dlPtr2 = dlPtr2->nextPtr) {
/* Empty loop body. */
}
dlPtr2->nextPtr = dlPtr;
dlPtr = newPtr;
}
/*
* Skip to the next line, and update the y-position while
* skipping.
*/
do {
dlPtr->y = y;
y += dlPtr->height;
prevPtr = dlPtr;
dlPtr = dlPtr->nextPtr;
} while ((dlPtr != NULL) && (dlPtr->linePtr == linePtr));
linePtr = TkBTreeNextLine(linePtr);
line++;
/*
* It's important to have the following check here rather than in
* the while statement for the loop, so that there's always at least
* one DLine generated, regardless of how small the window is. This
* keeps a lot of other code from breaking.
*/
if (y >= maxY) {
break;
}
}
/*
* Delete any DLine structures that don't fit on the screen and free
* up the tag array.
*/
FreeDLines(textPtr, dlPtr, (DLine *) NULL, 1);
if (tagInfo.tagPtrs != NULL) {
ckfree((char *) tagInfo.tagPtrs);
}
/*
* Arrange for scrollbars to be updated.
*/
textPtr->flags |= UPDATE_SCROLLBARS;
}
/*
*----------------------------------------------------------------------
*
* FreeDLines --
*
* This procedure is called to free up all of the resources
* associated with one or more DLine structures.
*
* Results:
* None.
*
* Side effects:
* Memory gets freed and various other resources are released.
*
*----------------------------------------------------------------------
*/
static void
FreeDLines(textPtr, firstPtr, lastPtr, unlink)
TkText *textPtr; /* Information about overall text
* widget. */
register DLine *firstPtr; /* Pointer to first DLine to free up. */
DLine *lastPtr; /* Pointer to DLine just after last
* one to free (NULL means everything
* starting with firstPtr). */
int unlink; /* 1 means DLines are currently linked
* into the list rooted at
* textPtr->dInfoPtr->dLinePtr and
* they have to be unlinked. 0 means
* just free without unlinking. */
{
register Chunk *chunkPtr, *nextChunkPtr;
register DLine *nextDLinePtr;
if (unlink) {
if (textPtr->dInfoPtr->dLinePtr == firstPtr) {
textPtr->dInfoPtr->dLinePtr = lastPtr;
} else {
register DLine *prevPtr;
for (prevPtr = textPtr->dInfoPtr->dLinePtr;
prevPtr->nextPtr != firstPtr; prevPtr = prevPtr->nextPtr) {
/* Empty loop body. */
}
prevPtr->nextPtr = lastPtr;
}
}
while (firstPtr != lastPtr) {
nextDLinePtr = firstPtr->nextPtr;
for (chunkPtr = firstPtr->chunkPtr; chunkPtr != NULL;
chunkPtr = nextChunkPtr) {
FreeStyle(textPtr, chunkPtr->stylePtr);
nextChunkPtr = chunkPtr->nextPtr;
ckfree((char *) chunkPtr);
}
ckfree((char *) firstPtr);
firstPtr = nextDLinePtr;
}
}
/*
*----------------------------------------------------------------------
*
* DisplayDLine --
*
* This procedure is invoked to draw a single line on the
* screen.
*
* Results:
* None.
*
* Side effects:
* The line given by dlPtr is drawn at its correct position in
* textPtr's window. Note that this is one *display* line, not
* one *text* line.
*
*----------------------------------------------------------------------
*/
static void
DisplayDLine(textPtr, dlPtr, pixmap)
TkText *textPtr; /* Text widget in which to draw line. */
register DLine *dlPtr; /* Information about line to draw. */
Pixmap pixmap; /* Pixmap to use for double-buffering.
* Caller must make sure it's large enough
* to hold line. */
{
register Style *stylePtr;
register StyleValues *sValuePtr;
register Chunk *chunkPtr;
DInfo *dInfoPtr = textPtr->dInfoPtr;
Display *display;
int width, height, count, x;
XFontStruct *fontPtr;
/*
* First, clear the area of the line to the background color for the
* text widget.
*/
display = Tk_Display(textPtr->tkwin);
Tk_Fill3DRectangle(display, pixmap, textPtr->border, 0, 0,
Tk_Width(textPtr->tkwin), dlPtr->height, 0, TK_RELIEF_FLAT);
/*
* Next, cycle through all of the chunks in the line displaying
* backgrounds. We need to do two passes, one for the backgrounds
* and one for the characters, because some characters (e.g. italics
* with heavy slants) may cross background boundaries. If some
* backgrounds are drawn after some text, the later backgrounds may
* obliterate parts of earlier characters.
*/
for (chunkPtr = dlPtr->chunkPtr; chunkPtr != NULL;
chunkPtr = chunkPtr->nextPtr) {
/*
* Draw a special background for this chunk if one is specified
* in its style. Two tricks here:
* 1. if this is the last chunk in the line then extend the
* background across to the end of the line.
* 2. if the background is stippled, then we have to draw the
* stippled part specially, since Tk_Fill3DRectangle doesn't
* do stipples.
*/
stylePtr = chunkPtr->stylePtr;
sValuePtr = stylePtr->sValuePtr;
if (sValuePtr->border != NULL) {
if (chunkPtr->nextPtr != NULL) {
width = chunkPtr->nextPtr->x - chunkPtr->x;
} else {
width = Tk_Width(textPtr->tkwin) - chunkPtr->x;
}
if (stylePtr->bgGC != None) {
XFillRectangle(display, pixmap, stylePtr->bgGC, chunkPtr->x,
0, (unsigned int) width, (unsigned int) dlPtr->height);
Tk_Draw3DRectangle(display, pixmap, sValuePtr->border,
chunkPtr->x, 0, width, dlPtr->height,
sValuePtr->borderWidth, sValuePtr->relief);
} else {
Tk_Fill3DRectangle(display, pixmap, sValuePtr->border,
chunkPtr->x, 0, width, dlPtr->height,
sValuePtr->borderWidth, sValuePtr->relief);
}
}
}
/*
* If the insertion cursor is displayed on this line, then draw it
* now, on top of the background but before the text. As a special
* hack to keep the cursor visible on mono displays, write the default
* background in the cursor area (instead of nothing) when the cursor
* isn't on. Otherwise the selection would hide the cursor.
*/
if ((textPtr->insertAnnotPtr->linePtr == dlPtr->linePtr)
&& (textPtr->state == tkTextNormalUid)
&& (textPtr->flags & GOT_FOCUS)) {
for (chunkPtr = dlPtr->chunkPtr; chunkPtr != NULL;
chunkPtr = chunkPtr->nextPtr) {
count = textPtr->insertAnnotPtr->ch
- (chunkPtr->text - dlPtr->linePtr->bytes);
if (count < 0) {
break;
}
if (count > chunkPtr->numChars) {
continue;
}
/*
* Deciding whether to display the cursor just after the last
* character in a line is tricky because of various wrap
* modes. Do it unless we're in character wrap mode and
* this line wraps, in which case it's better to display the
* cursor on the next line. For word wrap, there's an
* undisplayed space character that the user must be able to
* position the cursor in front of. For no wrap, there's no
* next line on which to display the cursor.
*/
if ((count == chunkPtr->numChars)
&& (textPtr->wrapMode == tkTextCharUid)
&& (chunkPtr->text[count] != '\n')) {
continue;
}
fontPtr = chunkPtr->stylePtr->sValuePtr->fontPtr;
TkMeasureChars(fontPtr, chunkPtr->text, count, chunkPtr->x,
(int) 1000000, 0, &x);
if (textPtr->flags & INSERT_ON) {
Tk_Fill3DRectangle(display, pixmap, textPtr->insertBorder,
x - textPtr->insertWidth/2,
dlPtr->baseline - fontPtr->ascent,
textPtr->insertWidth,
fontPtr->ascent + fontPtr->descent,
textPtr->insertBorderWidth, TK_RELIEF_RAISED);
} else if (Tk_GetColorModel(textPtr->tkwin) != TK_COLOR) {
Tk_Fill3DRectangle(display, pixmap, textPtr->border,
x - textPtr->insertWidth/2,
dlPtr->baseline - fontPtr->ascent,
textPtr->insertWidth,
fontPtr->ascent + fontPtr->descent,
0, TK_RELIEF_FLAT);
}
}
}
/*
* Make another pass through all of the chunks to redraw all of
* the text (and underlines, etc., if they're wanted).
*/
for (chunkPtr = dlPtr->chunkPtr; chunkPtr != NULL;
chunkPtr = chunkPtr->nextPtr) {
stylePtr = chunkPtr->stylePtr;
sValuePtr = stylePtr->sValuePtr;
if (chunkPtr->numChars > 0) {
TkDisplayChars(display, pixmap, stylePtr->fgGC, sValuePtr->fontPtr,
chunkPtr->text, chunkPtr->numChars, chunkPtr->x,
dlPtr->baseline, 0);
if (sValuePtr->underline) {
TkUnderlineChars(display, pixmap, stylePtr->fgGC,
sValuePtr->fontPtr, chunkPtr->text, chunkPtr->x,
dlPtr->baseline, 0, 0, chunkPtr->numChars-1);
}
}
}
/*
* Copy the pixmap onto the screen. If this is the last line on
* the screen, only copy a piece of the line, so that it doesn't
* overflow into the border area. Another special trick: copy the
* padding area to the left of the line; this is because the
* insertion cursor sometimes overflows onto that area and we want
* to get as much of the cursor as possible.
*/
height = dlPtr->height;
if ((height + dlPtr->y) > dInfoPtr->maxY) {
height = dInfoPtr->maxY - dlPtr->y;
}
XCopyArea(display, pixmap, Tk_WindowId(textPtr->tkwin),
dInfoPtr->copyGC, dInfoPtr->x - textPtr->padX, 0,
dInfoPtr->maxX - (dInfoPtr->x - textPtr->padX),
height, dInfoPtr->x - textPtr->padX, dlPtr->y);
linesRedrawn++;
}
/*
*----------------------------------------------------------------------
*
* DisplayText --
*
* This procedure is invoked as a when-idle handler to update the
* display. It only redisplays the parts of the text widget that
* are out of date.
*
* Results:
* None.
*
* Side effects:
* Information is redrawn on the screen.
*
*----------------------------------------------------------------------
*/
static void
DisplayText(clientData)
ClientData clientData; /* Information about widget. */
{
register TkText *textPtr = (TkText *) clientData;
DInfo *dInfoPtr = textPtr->dInfoPtr;
Tk_Window tkwin;
register DLine *dlPtr;
Pixmap pixmap;
int maxHeight;
int bottomY = 0; /* Initialization needed only to stop
* compiler warnings. */
if ((textPtr->tkwin == NULL) || !Tk_IsMapped(textPtr->tkwin)
|| (dInfoPtr->maxX <= dInfoPtr->x)
|| (dInfoPtr->maxY <= dInfoPtr->y)) {
UpdateDisplayInfo(textPtr);
goto doScrollbars;
}
numRedisplays++;
/*
* Choose a new current item if that is needed (this could cause
* event handlers to be invoked, hence the preserve/release calls
* and the loop, since the handlers could conceivably necessitate
* yet another current item calculation). The tkwin check is because
* the whole window could go away in the Tk_Release call.
*/
while (dInfoPtr->flags & REPICK_NEEDED) {
Tk_Preserve((ClientData) textPtr);
dInfoPtr->flags &= ~REPICK_NEEDED;
TkTextPickCurrent(textPtr, &textPtr->pickEvent);
tkwin = textPtr->tkwin;
Tk_Release((ClientData) textPtr);
if (tkwin == NULL) {
return;
}
}
/*
* First recompute what's supposed to be displayed.
*/
UpdateDisplayInfo(textPtr);
/*
* Redraw the borders if that's needed.
*/
if (dInfoPtr->flags & REDRAW_BORDERS) {
Tk_Draw3DRectangle(Tk_Display(textPtr->tkwin),
Tk_WindowId(textPtr->tkwin), textPtr->border,
0, 0, Tk_Width(textPtr->tkwin), Tk_Height(textPtr->tkwin),
textPtr->borderWidth, textPtr->relief);
}
/*
* See if it's possible to bring some parts of the screen up-to-date
* by scrolling (copying from other parts of the screen).
*/
for (dlPtr = dInfoPtr->dLinePtr; dlPtr != NULL; dlPtr = dlPtr->nextPtr) {
register DLine *dlPtr2;
int offset, height, y;
if ((dlPtr->oldY == -1) || (dlPtr->y == dlPtr->oldY)
|| ((dlPtr->oldY + dlPtr->height) > dInfoPtr->maxY)) {
continue;
}
/*
* This line is already drawn somewhere in the window so it only
* needs to be copied to its new location. See if there's a group
* of lines that can all be copied together.
*/
offset = dlPtr->y - dlPtr->oldY;
height = dlPtr->height;
y = dlPtr->y;
for (dlPtr2 = dlPtr->nextPtr; dlPtr2 != NULL;
dlPtr2 = dlPtr2->nextPtr) {
if ((dlPtr2->oldY == -1)
|| ((dlPtr2->oldY + offset) != dlPtr2->y)
|| ((dlPtr2->oldY + dlPtr2->height) > dInfoPtr->maxY)) {
break;
}
height += dlPtr2->height;
}
/*
* Copy the information and update the lines to show that they've
* been copied. Reduce the height of the area being copied if
* necessary to avoid overwriting the border area.
*/
if ((y + height) > dInfoPtr->maxY) {
height = dInfoPtr->maxY -y;
}
XCopyArea(Tk_Display(textPtr->tkwin), Tk_WindowId(textPtr->tkwin),
Tk_WindowId(textPtr->tkwin), dInfoPtr->scrollGC,
dInfoPtr->x - textPtr->padX, dlPtr->oldY,
dInfoPtr->maxX - (dInfoPtr->x - textPtr->padX),
height, dInfoPtr->x - textPtr->padX, y);
numCopies++;
while (1) {
dlPtr->oldY = dlPtr->y;
if (dlPtr->nextPtr == dlPtr2) {
break;
}
dlPtr = dlPtr->nextPtr;
}
/*
* Scan through the lines following the copied ones to see if
* we just overwrote them with the copy operation. If so, mark
* them for redisplay.
*/
for ( ; dlPtr2 != NULL; dlPtr2 = dlPtr2->nextPtr) {
if ((dlPtr2->oldY != -1)
&& ((dlPtr2->oldY + dlPtr2->height) > y)
&& (dlPtr2->oldY < (y + height))) {
dlPtr2->oldY = -1;
}
}
/*
* It's possible that part of the area copied above was obscured.
* To handle this situation, read expose-related events generated
* during the XCopyArea operation.
*/
while (1) {
XEvent event;
XWindowEvent(Tk_Display(textPtr->tkwin),
Tk_WindowId(textPtr->tkwin), ExposureMask, &event);
if (event.type == NoExpose) {
break;
} else if (event.type == GraphicsExpose) {
TkTextRedrawRegion(textPtr, event.xgraphicsexpose.x,
event.xgraphicsexpose.y, event.xgraphicsexpose.width,
event.xgraphicsexpose.height);
if (event.xgraphicsexpose.count == 0) {
damagedCopies++;
break;
}
} else if (event.type == Expose) {
/*
* A tricky situation. This event must already have been
* queued up before the XCopyArea was issued. If the area
* in this event overlaps the area copied, then some of the
* bits that were copied were bogus. The easiest way to
* handle this is to issue two redisplays: one for the
* original area and one for the area shifted as if it was
* in the copied area.
*/
TkTextRedrawRegion(textPtr, event.xexpose.x,
event.xexpose.y, event.xexpose.width,
event.xexpose.height);
TkTextRedrawRegion(textPtr, event.xexpose.x,
event.xexpose.y + offset, event.xexpose.width,
event.xexpose.height);
} else {
panic("DisplayText received unknown exposure event");
}
}
}
/*
* Now we have to redraw the lines that couldn't be updated by
* scrolling. First, compute the height of the largest line and
* allocate an off-screen pixmap to use for double-buffered
* displays.
*/
maxHeight = -1;
for (dlPtr = dInfoPtr->dLinePtr; dlPtr != NULL;
dlPtr = dlPtr->nextPtr) {
if ((dlPtr->height > maxHeight) && (dlPtr->oldY != dlPtr->y)) {
maxHeight = dlPtr->height;
}
bottomY = dlPtr->y + dlPtr->height;
}
if (maxHeight > dInfoPtr->maxY) {
maxHeight = dInfoPtr->maxY;
}
if (maxHeight >= 0) {
pixmap = XCreatePixmap(Tk_Display(textPtr->tkwin),
Tk_WindowId(textPtr->tkwin), Tk_Width(textPtr->tkwin),
maxHeight, Tk_Depth(textPtr->tkwin));
for (dlPtr = textPtr->dInfoPtr->dLinePtr;
(dlPtr != NULL) && (dlPtr->y < dInfoPtr->maxY);
dlPtr = dlPtr->nextPtr) {
if (dlPtr->oldY != dlPtr->y) {
DisplayDLine(textPtr, dlPtr, pixmap);
dlPtr->oldY = dlPtr->y;
}
}
XFreePixmap(Tk_Display(textPtr->tkwin), pixmap);
}
/*
* Lastly, see if we need to refresh the part of the window below
* the last line of text (if there is any such area). Refresh the
* padding area on the left too, since the insertion cursor might
* have been displayed there previously).
*/
if (dInfoPtr->topOfEof > dInfoPtr->maxY) {
dInfoPtr->topOfEof = dInfoPtr->maxY;
}
if (bottomY < dInfoPtr->topOfEof) {
Tk_Fill3DRectangle(Tk_Display(textPtr->tkwin),
Tk_WindowId(textPtr->tkwin), textPtr->border,
dInfoPtr->x - textPtr->padX, bottomY,
dInfoPtr->maxX - (dInfoPtr->x - textPtr->padX),
dInfoPtr->topOfEof-bottomY, 0, TK_RELIEF_FLAT);
}
dInfoPtr->topOfEof = bottomY;
if (dInfoPtr->topOfEof > dInfoPtr->maxY) {
dInfoPtr->topOfEof = dInfoPtr->maxY;
}
doScrollbars:
/*
* Update the vertical scrollbar, if there is one.
*/
if ((textPtr->flags & UPDATE_SCROLLBARS) && (textPtr->yScrollCmd != NULL)) {
int numLines, first, result, maxY, height;
TkTextLine *linePtr;
char string[60];
/*
* Count the number of text lines on the screen.
*/
textPtr->flags &= ~UPDATE_SCROLLBARS;
maxY = 0;
for (numLines = 0, linePtr = NULL, dlPtr = dInfoPtr->dLinePtr;
dlPtr != NULL; dlPtr = dlPtr->nextPtr) {
if (dlPtr->linePtr != linePtr) {
numLines++;
linePtr = dlPtr->linePtr;
}
maxY = dlPtr->y + dlPtr->height;
}
/*
* If the screen isn't completely full, then estimate the number of
* lines that would fit on it if it were full.
*/
height = dInfoPtr->maxY - dInfoPtr->y;
if (numLines == 0) {
numLines = height /
(textPtr->fontPtr->ascent + textPtr->fontPtr->descent);
} else if (maxY < height) {
numLines = (numLines * height)/maxY;
}
first = TkBTreeLineIndex(dInfoPtr->dLinePtr->linePtr);
sprintf(string, " %d %d %d %d", TkBTreeNumLines(textPtr->tree),
numLines, first, first+numLines-1);
result = Tcl_VarEval(textPtr->interp, textPtr->yScrollCmd, string,
(char *) NULL);
if (result != TCL_OK) {
Tcl_AddErrorInfo(textPtr->interp,
"\n (horizontal scrolling command executed by text)");
Tk_BackgroundError(textPtr->interp);
}
}
dInfoPtr->flags &= ~(REDRAW_PENDING|REDRAW_BORDERS);
}
/*
*----------------------------------------------------------------------
*
* TkTextRedrawRegion --
*
* This procedure is invoked to schedule a redisplay for a given
* region of a text widget. The redisplay itself may not occur
* immediately: it's scheduled as a when-idle handler.
*
* Results:
* None.
*
* Side effects:
* Information will eventually be redrawn on the screen.
*
*----------------------------------------------------------------------
*/
/* ARGSUSED */
void
TkTextRedrawRegion(textPtr, x, y, width, height)
TkText *textPtr; /* Widget record for text widget. */
int x, y; /* Coordinates of upper-left corner of area
* to be redrawn, in pixels relative to
* textPtr's window. */
int width, height; /* Width and height of area to be redrawn. */
{
register DLine *dlPtr;
DInfo *dInfoPtr = textPtr->dInfoPtr;
int maxY;
/*
* Find all lines that overlap the given region and mark them for
* redisplay.
*/
maxY = y + height;
for (dlPtr = dInfoPtr->dLinePtr; dlPtr != NULL;
dlPtr = dlPtr->nextPtr) {
if (((dlPtr->y + dlPtr->height) > y) && (dlPtr->y < maxY)) {
dlPtr->oldY = -1;
}
}
if (dInfoPtr->topOfEof < maxY) {
dInfoPtr->topOfEof = maxY;
}
/*
* Schedule the redisplay operation if there isn't one already
* scheduled.
*/
if (!(dInfoPtr->flags & REDRAW_PENDING)) {
dInfoPtr->flags |= REDRAW_PENDING;
Tk_DoWhenIdle(DisplayText, (ClientData) textPtr);
}
if ((x < dInfoPtr->x) || (y < dInfoPtr->y)
|| ((x + width) > dInfoPtr->maxX) || (maxY > dInfoPtr->maxY)) {
dInfoPtr->flags |= REDRAW_BORDERS;
}
}
/*
*----------------------------------------------------------------------
*
* TkTextLinesChanged --
*
* This procedure is invoked when lines in a text widget are about
* to be modified in a way that changes how they are displayed (e.g.
* characters were inserted, the line was deleted, or tag information
* was changed). This procedure must be called *before* a change is
* made, so that pointers to TkTextLines in the display information
* are still valid.
*
* Results:
* None.
*
* Side effects:
* The indicated lines will be redisplayed at some point in the
* future (the actual redisplay is scheduled as a when-idle handler).
*
*----------------------------------------------------------------------
*/
void
TkTextLinesChanged(textPtr, first, last)
TkText *textPtr; /* Widget record for text widget. */
int first; /* Index of first line that must be
* redisplayed. */
int last; /* Index of last line to redisplay. */
{
DInfo *dInfoPtr = textPtr->dInfoPtr;
DLine *firstPtr, *lastPtr;
/*
* Find the DLines corresponding to first and last+1.
*/
firstPtr = FindDLine(dInfoPtr->dLinePtr, first);
if (firstPtr == NULL) {
return;
}
lastPtr = FindDLine(dInfoPtr->dLinePtr, last+1);
if (firstPtr == lastPtr) {
return;
}
/*
* Delete all the DLines from first up through last (but not including
* lastPtr, which points to the first line *outside* the range).
*/
FreeDLines(textPtr, firstPtr, lastPtr, 1);
/*
* Schedule both a redisplay and a recomputation of display information.
*/
if (!(dInfoPtr->flags & REDRAW_PENDING)) {
Tk_DoWhenIdle(DisplayText, (ClientData) textPtr);
}
dInfoPtr->flags |= REDRAW_PENDING|DINFO_OUT_OF_DATE|REPICK_NEEDED;
}
/*
*----------------------------------------------------------------------
*
* TkTextRedrawTag --
*
* This procedure is invoked to request a redraw of all characters
* in a given range of characters that have a particular tag on or
* off. It's called, for example, when characters are tagged or
* untagged, or when tag options change.
*
* Results:
* None.
*
* Side effects:
* Information on the screen may be redrawn, and the layout of
* the screen may change.
*
*----------------------------------------------------------------------
*/
void
TkTextRedrawTag(textPtr, line1, ch1, line2, ch2, tagPtr, withTag)
TkText *textPtr; /* Widget record for text widget. */
int line1, ch1; /* Index of first character in range of
* interest. */
int line2, ch2; /* Index of character just after last one
* in range of interest. */
TkTextTag *tagPtr; /* Information about tag. */
int withTag; /* 1 means redraw characters that have the
* tag, 0 means redraw those without. */
{
register DLine *dlPtr;
DLine *endPtr;
int topLine, tagOn;
TkTextSearch search;
DInfo *dInfoPtr = textPtr->dInfoPtr;
/*
* Round up the starting position if it's before the first line
* visible on the screen (we only care about what's on the screen).
*/
dlPtr = dInfoPtr->dLinePtr;
if (dlPtr == NULL) {
return;
}
topLine = TkBTreeLineIndex(dlPtr->linePtr);
if (topLine > line1) {
line1 = topLine;
ch1 = 0;
}
/*
* Initialize a search through all transitions on the tag, starting
* with the first transition where the tag's current state is different
* from what it will eventually be.
*/
TkBTreeStartSearch(textPtr->tree, line1, ch1+1, line2, ch2,
tagPtr, &search);
if (search.linePtr == NULL) {
return;
}
tagOn = TkBTreeCharTagged(search.linePtr, ch1, tagPtr);
if (tagOn != withTag) {
if (!TkBTreeNextTag(&search)) {
return;
}
}
/*
* Each loop through the loop below is for one range of characters
* where the tag's current state is different than its eventual
* state. At the top of the loop, search contains information about
* the first character in the range.
*/
while (1) {
/*
* Find the first DLine structure in the range.
*/
dlPtr = FindDLine(dlPtr, search.line1);
if (dlPtr == NULL) {
break;
}
/*
* Find the first DLine structure that's past the end of the range.
*/
if (TkBTreeNextTag(&search)) {
endPtr = FindDLine(dlPtr,
(search.ch1 > 0) ? (search.line1 + 1) : search.line1);
} else {
endPtr = FindDLine(dlPtr,
(ch2 > 0) ? (search.line2 + 1) : search.line2);
}
/*
* Delete all of the display lines in the range, so that they'll
* be re-layed out and redrawn.
*/
FreeDLines(textPtr, dlPtr, endPtr, 1);
dlPtr = endPtr;
/*
* Find the first text line in the next range.
*/
if (!TkBTreeNextTag(&search)) {
break;
}
}
/*
* Lastly, schedule a redisplay and layout recalculation if they
* aren't already pending.
*/
if (!(dInfoPtr->flags & REDRAW_PENDING)) {
Tk_DoWhenIdle(DisplayText, (ClientData) textPtr);
}
dInfoPtr->flags |= REDRAW_PENDING|DINFO_OUT_OF_DATE|REPICK_NEEDED;
}
/*
*----------------------------------------------------------------------
*
* TkTextRelayoutWindow --
*
* This procedure is called when something has happened that
* invalidates the whole layout of characters on the screen, such
* as a change in a configuration option for the overall text
* widget or a change in the window size. It causes all display
* information to be recomputed and the window to be redrawn.
*
* Results:
* None.
*
* Side effects:
* All the display information will be recomputed for the window
* and the window will be redrawn.
*
*----------------------------------------------------------------------
*/
void
TkTextRelayoutWindow(textPtr)
TkText *textPtr; /* Widget record for text widget. */
{
DInfo *dInfoPtr = textPtr->dInfoPtr;
/*
* Throw away all the current layout information.
*/
FreeDLines(textPtr, dInfoPtr->dLinePtr, (DLine *) NULL, 1);
dInfoPtr->dLinePtr = NULL;
/*
* Recompute some overall things for the layout.
*/
dInfoPtr->x = textPtr->borderWidth + textPtr->padX;
dInfoPtr->y = textPtr->borderWidth + textPtr->padY;
dInfoPtr->maxX = Tk_Width(textPtr->tkwin) - dInfoPtr->x;
dInfoPtr->maxY = Tk_Height(textPtr->tkwin) - dInfoPtr->y;
dInfoPtr->topOfEof = dInfoPtr->maxY;
if (!(dInfoPtr->flags & REDRAW_PENDING)) {
Tk_DoWhenIdle(DisplayText, (ClientData) textPtr);
}
dInfoPtr->flags |= REDRAW_PENDING|REDRAW_BORDERS|DINFO_OUT_OF_DATE
|REPICK_NEEDED;
}
/*
*----------------------------------------------------------------------
*
* TkTextSetView --
*
* This procedure is called to specify what lines are to be
* displayed in a text widget.
*
* Results:
* None.
*
* Side effects:
* The display will (eventually) be updated so that the line
* given by "line" is visible on the screen at the position
* determined by "pickPlace".
*
*----------------------------------------------------------------------
*/
void
TkTextSetView(textPtr, line, pickPlace)
TkText *textPtr; /* Widget record for text widget. */
int line; /* Number of line that is to appear somewhere
* in the window. */
int pickPlace; /* 0 means topLine must appear at top of
* screen. 1 means we get to pick where it
* appears: minimize screen motion or else
* display line at center of screen. */
{
DInfo *dInfoPtr = textPtr->dInfoPtr;
register DLine *dlPtr, *dlPtr2;
TkTextLine *linePtr;
int curTopLine, curBotLine, numLines;
int bottomY;
TagInfo tagInfo;
#define CLOSE_LINES 5
numLines = TkBTreeNumLines(textPtr->tree);
if (line >= numLines) {
line = numLines-1;
}
if (line < 0) {
line = 0;
}
linePtr = TkBTreeFindLine(textPtr->tree, line);
if (!pickPlace) {
/*
* The line must go at the top of the screen. See if the new
* topmost line is already somewhere on the screen. If so then
* delete all the DLine structures ahead of it. Otherwise just
* leave all the DLine's alone (if the new topmost line is above
* the top of the current window, i.e. we're scrolling back towards
* the beginning of the file we may be able to reuse some of the
* information that's currently on the screen without redisplaying
* it all.
*/
dlPtr = FindDLine(dInfoPtr->dLinePtr, line);
if ((dlPtr != NULL) && (dlPtr != dInfoPtr->dLinePtr)) {
FreeDLines(textPtr, dInfoPtr->dLinePtr, dlPtr, 1);
}
textPtr->topLinePtr = linePtr;
goto scheduleUpdate;
}
/*
* We have to pick where to display the given line. First, bring
* the display information up to date and see if the line will be
* completely visible in the current screen configuration. If so
* then there's nothing to do.
*/
if (dInfoPtr->flags & DINFO_OUT_OF_DATE) {
UpdateDisplayInfo(textPtr);
}
for (dlPtr = dInfoPtr->dLinePtr; ; dlPtr = dlPtr->nextPtr) {
if (dlPtr->nextPtr == NULL) {
break;
}
if ((dlPtr->linePtr == linePtr)
&& (dlPtr->nextPtr->linePtr != linePtr)) {
break;
}
}
if ((dlPtr->linePtr == linePtr)
&& ((dlPtr->y + dlPtr->height) <= dInfoPtr->maxY)) {
return;
}
/*
* The desired line isn't already on-screen. See if it is within
* a few lines of the top of the window. If so then just make it
* the top line on the screen.
*/
bottomY = (dInfoPtr->y + dInfoPtr->maxY)/2;
curTopLine = TkBTreeLineIndex(dInfoPtr->dLinePtr->linePtr);
if (line < curTopLine) {
if (line >= (curTopLine-CLOSE_LINES)) {
textPtr->topLinePtr = TkBTreeFindLine(textPtr->tree, line);
goto scheduleUpdate;
}
} else {
/*
* The desired line is below the bottom of the screen. If it is
* within a few lines of the bottom of the screen then position
* it at the bottom of the screen. (At this point dlPtr points to
* the last line on the screen)
*/
curBotLine = TkBTreeLineIndex(dlPtr->linePtr);
if (line <= (curBotLine+5)) {
bottomY = dInfoPtr->maxY;
}
}
/*
* Our job now is arrange the display so that "line" appears as
* low on the screen as possible but with its bottom no lower
* than bottomY (bottomY is the bottom of the window if the
* desired line is just below the current screen, otherwise it
* is the center of the window. Work upwards (through smaller
* line numbers) computing how much space lines take, until we
* fine the line that should be at the top of the screen.
*/
for (textPtr->topLinePtr = linePtr = TkBTreeFindLine(textPtr->tree, line);
; line--, textPtr->topLinePtr = linePtr,
linePtr = TkBTreeFindLine(textPtr->tree, line)) {
tagInfo.tagPtrs = TkBTreeGetTags(textPtr->tree, linePtr, 0,
&tagInfo.numTags);
tagInfo.arraySize = tagInfo.numTags;
TkBTreeStartSearch(textPtr->tree, line, 1, line+1, 0,
(TkTextTag *) NULL, &tagInfo.search);
TkBTreeNextTag(&tagInfo.search);
dlPtr = LayoutLine(textPtr, line, linePtr, &tagInfo);
for (dlPtr2 = dlPtr; dlPtr2 != NULL; dlPtr2 = dlPtr2->nextPtr) {
bottomY -= dlPtr2->height;
}
FreeDLines(textPtr, dlPtr, (DLine *) NULL, 0);
if (tagInfo.tagPtrs != NULL) {
ckfree((char *) tagInfo.tagPtrs);
}
if ((bottomY <= 0) || (line <= 0)) {
break;
}
}
scheduleUpdate:
if (!(dInfoPtr->flags & REDRAW_PENDING)) {
Tk_DoWhenIdle(DisplayText, (ClientData) textPtr);
}
dInfoPtr->flags |= REDRAW_PENDING|DINFO_OUT_OF_DATE|REPICK_NEEDED;
}
/*
*----------------------------------------------------------------------
*
* FindDLine --
*
* This procedure is called to find the DLine corresponding to a
* given text line.
*
* Results:
* The return value is a pointer to the first DLine found in the
* list headed by dlPtr whose line number is greater or equal to
* line. If there is no such line in the list then NULL is returned.
*
* Side effects:
* None.
*
*----------------------------------------------------------------------
*/
static DLine *
FindDLine(dlPtr, line)
register DLine *dlPtr; /* Pointer to first in list of DLines
* to search. */
int line; /* Line number in text that is desired. */
{
TkTextLine *linePtr;
int thisLine;
if (dlPtr == NULL) {
return NULL;
}
thisLine = TkBTreeLineIndex(dlPtr->linePtr);
while (thisLine < line) {
/*
* This DLine isn't the right one. Go on to the next DLine
* (skipping multiple DLine's for the same text line).
*/
linePtr = dlPtr->linePtr;
do {
dlPtr = dlPtr->nextPtr;
if (dlPtr == NULL) {
return NULL;
}
} while (dlPtr->linePtr == linePtr);
/*
* Step through text lines, keeping track of the line number
* we're on, until we catch up to dlPtr (remember, there could
* be gaps in the DLine list where DLine's have been deleted).
*/
do {
linePtr = TkBTreeNextLine(linePtr);
thisLine++;
if (linePtr == NULL) {
panic("FindDLine reached end of text");
}
} while (linePtr != dlPtr->linePtr);
}
return dlPtr;
}
/*
*----------------------------------------------------------------------
*
* TkTextCharAtLoc --
*
* Given an (x,y) coordinate on the screen, find the location of
* the closest character to that location.
*
* Results:
* The return value is a pointer to the text line containing the
* character displayed closest to (x,y). The value at *chPtr is
* overwritten with the index with that line of the closest
* character.
*
* Side effects:
* None.
*
*----------------------------------------------------------------------
*/
TkTextLine *
TkTextCharAtLoc(textPtr, x, y, chPtr)
TkText *textPtr; /* Widget record for text widget. */
int x, y; /* Pixel coordinates of point in widget's
* window. */
int *chPtr; /* Place to store index-within-line of
* closest character. */
{
DInfo *dInfoPtr = textPtr->dInfoPtr;
register DLine *dlPtr;
register Chunk *chunkPtr;
int count;
int endX;
/*
* Make sure that all of the layout information about what's
* displayed where on the screen is up-to-date.
*/
if (dInfoPtr->flags & DINFO_OUT_OF_DATE) {
UpdateDisplayInfo(textPtr);
}
/*
* If the coordinates are above the top of the window, then adjust
* them to refer to the upper-right corner of the window.
*/
if (y < dInfoPtr->y) {
y = dInfoPtr->y;
x = dInfoPtr->x;
} else if (y >= dInfoPtr->topOfEof) {
y = dInfoPtr->topOfEof;
x = dInfoPtr->maxX;
}
for (dlPtr = dInfoPtr->dLinePtr; dlPtr != NULL; dlPtr = dlPtr->nextPtr) {
if (y > (dlPtr->y + dlPtr->height)) {
if (dlPtr->nextPtr != NULL) {
continue;
}
/*
* The coordinates are off the bottom of the window. Adjust
* them to refer to the lower-right character on the window.
*/
y = dlPtr->y;
x = dInfoPtr->maxX;
}
for (chunkPtr = dlPtr->chunkPtr; ; chunkPtr = chunkPtr->nextPtr) {
if ((chunkPtr->nextPtr == NULL) || (chunkPtr->nextPtr->x > x)) {
break;
}
}
count = TkMeasureChars(chunkPtr->stylePtr->sValuePtr->fontPtr,
chunkPtr->text, chunkPtr->numChars, chunkPtr->x, x, 0, &endX);
if (count >= chunkPtr->numChars) {
/*
* The point is off the end of the line. Return the character
* after the last one that fit, unless that character appears
* as the first character on the next DLine or unless the last
* one that fit extends beyond the edge of the window.
*/
if ((dlPtr->nextPtr != NULL)
&& (dlPtr->nextPtr->chunkPtr->text
== (chunkPtr->text + chunkPtr->numChars))) {
count = chunkPtr->numChars-1;
}
if (endX >= dInfoPtr->maxX) {
count = chunkPtr->numChars-1;
}
}
*chPtr = count + (chunkPtr->text - dlPtr->linePtr->bytes);
return dlPtr->linePtr;
}
panic("TkTextCharAtLoc ran out of lines");
return (TkTextLine *) NULL;
}