/*
 * DBWdisplay.c --
 *
 * This file contains code for redisplaying layout on the display.
 * It saves up information about what is to be redisplayed, then
 * does all of the redisplay at a convenient time.
 *
 *     *********************************************************************
 *     * Copyright (C) 1985, 1990 Regents of the University of California. *
 *     * Permission to use, copy, modify, and distribute this              *
 *     * software and its documentation for any purpose and without        *
 *     * fee is hereby granted, provided that the above copyright          *
 *     * notice appear in all copies.  The University of California        *
 *     * makes no representations about the suitability of this            *
 *     * software for any purpose.  It is provided "as is" without         *
 *     * express or implied warranty.  Export of this software outside     *
 *     * of the United States of America may require an export license.    *
 *     *********************************************************************
 */

#ifndef lint
static char rcsid[] __attribute__ ((unused)) = "$Header: /usr/cvsroot/magic-8.0/dbwind/DBWdisplay.c,v 1.5 2008/12/11 04:20:05 tim Exp $";
#endif  /* not lint */

#include <stdio.h>
#include <stdlib.h>
#include <string.h>

#include "utils/magic.h"
#include "utils/malloc.h"
#include "utils/geometry.h"
#include "tiles/tile.h"
#include "utils/hash.h"
#include "database/database.h"
#include "windows/windows.h"
#include "graphics/graphics.h"
#include "dbwind/dbwind.h"
#include "utils/utils.h"
#include "dbwind/dbwtech.h"
#include "utils/styles.h"
#include "utils/main.h"
#include "utils/tech.h"
#include "utils/signals.h"

/* C99 compat */
#include "textio/textio.h"

/* The following variable is exported to the rest of the world.
 * It is read from the "styletype" line of the technology file,
 * and defines the class of display styles file expected for
 * this technology.  It defaults as below;  almost all technologies
 * can use the default.
 */

char *DBWStyleType = "std";

/* a round-up sort of integer division */
#define	ceilDiv(n,d)	( ((n) < 0)  ? -( ((-(n))+(d)-1) / d)  \
	: ((n)+(d)-1) / d )

static bool debugit = FALSE;

/* The following statics are just for convenience in talking between
 * the top-level redisplay routine and the lower-level redisplay
 * routines invoked during the recursive search.
 */

static MagWindow *dbwWindow;	/* Current window being redisplayed. */
static bool disWasPale;		/* TRUE if last rect was displayed pale */
static Rect rootClip;		/* Clip area for root area that is being
				 * redisplayed.
				 */
static Rect windClip;		/* Clip area for entire window. */
static int disStyle;		/* Display style. */
static Rect dbwWatchArea;	/* Area used to clip tiles being "watched" so
				 * that infinities don't cause arithmetic
				 * overflow.  In coords of cell being watched.
				 */
static Transform dbwWatchTrans;	/* Transform to root coords for watch tiles. */
static int dbwWatchDemo;	/* TRUE means use "demo" style for watch
				 * tile display.
				 */
static int  dbwSeeTypes;	/* TRUE means use tile type instead of
				   pointer value for watch display.
				*/
static Rect dbwMinBBox;		/* If bounding boxes aren't at least this
				 * large, don't bother displaying name and
				 * id.  The ur point of the box gives the
				 * minimum allowed dimensions.
				 */
static int dbwLabelSize;	/* Size to use for label drawing. */
static Rect *dbwExpandAmounts;	/* Box to accumulate total sizes of labels.
				 * Always refers to crec->dbw_expandAmounts
				 * in window being redrawn.
				 */

/* The stuff below is shared between the top-level and action
 * routines for redisplay.  It is used to identify the edit cell
 * so it can be displayed differently.
 */

static CellDef *editDef;
static Transform editTrans;	/* Contains transform from edit cell to
				 * screen coordinates.  If edit cell isn't
				 * in this window, editDef is NULL.
				 */
static bool dbwAllSame;		/* Means don't display the edit cell
				 * differently after all.
				 */

static bool dbwIsLocked;	/* Is window already locked */
static MagWindow *dbwLockW;	/* Window to lock */
static bool dbwNeedStyle;	/* Do we need to set the display style? */

int DBWNumStyles = 0;		/* Number of styles usable in layer
				 * definitions.  This is also the amount
				 * to add to a style index to get its
				 * "pale" (non-edit-cell) version
				 */

int RtrMetalWidth = 2;		/* These officially belong to the router */
int RtrPolyWidth = 2;		/* but they have been usurped for other	 */
int RtrContactWidth = 2;	/* purposes in DBWdisplay and in the plot
				 * module.
				 */

extern char *MainMonType;	/* from main/main.c */

/* Search functions, all of which are used before definition: */

extern int dbwTileFunc(), dbwWatchFunc(), dbwLabelFunc();
extern int dbwPaintFunc(), dbwBBoxFunc();
extern int dbwWindowFunc(), dbwChangedFunc();


/*
 * ----------------------------------------------------------------------------
 * DBWredisplay --
 *
 * 	This procedure does the dirty of redisplaying information
 *	on the graphics screen.  When it is done the given area of the
 *	window will be correctly displayed, including the grid, any
 *	watched tile planes, and tools.
 *
 *	This procedure locks windows as it goes.
 *
 * Results:
 *	None.
 *
 * Side effects:
 *	Stuff is drawn on the display in the given area.
 * ----------------------------------------------------------------------------
 */

void
DBWredisplay(
    MagWindow *w,			/* Window some of whose contents are to be
				 * redisplayed.
				 */
    Rect *rootArea,		/* The area that must be redisplayed, in
				 * root cell coordinates.
				 */
    Rect *clipArea)		/* The screen area that we should clip to
				 */
{
    int i;
    TileTypeBitMask *mask;
    SearchContext scontext;
    Rect largerArea, labelArea, screenArea;
    int bitMask, lambdasPerPixel, pixelsPerLambda;
    DBWclientRec *crec;
    CellDef *cellDef;
    TileTypeBitMask layers, rmask;

    /*
    TxPrintf("Root area (%d, %d) (%d, %d) redisplay.\n",
	    rootArea->r_xbot, rootArea->r_ybot,
	    rootArea->r_xtop, rootArea->r_ytop);
    */

#ifdef MAGIC_WRAPPER
    /* Honor the display suspend state */
    if (GrDisplayStatus == DISPLAY_SUSPEND) return;
#endif

    GrLock(w, TRUE);

    /* Round up the redisplay area by 1 pixel on all sides.  This
     * is needed because DBSrPaintArea won't return tiles that touch
     * the area without overlapping it.  Without the round-up, there
     * will be occasional (in fact, frequent), one-pixel wide slivers.
     */

    largerArea = *rootArea;
    largerArea.r_xbot -= 1;
    largerArea.r_ybot -= 1;
    largerArea.r_xtop += 1;
    largerArea.r_ytop += 1;

    crec = ((DBWclientRec *) w->w_clientData);
    cellDef = ((CellUse *)w->w_surfaceID)->cu_def;

    pixelsPerLambda = w->w_scale / SUBPIXEL;
    lambdasPerPixel = (SUBPIXEL / w->w_scale) + 1;

    if ((crec->dbw_origin.p_x != w->w_origin.p_x)
	|| (crec->dbw_origin.p_y != w->w_origin.p_y)
	|| (crec->dbw_scale != w->w_scale)
	|| (crec->dbw_surfaceArea.r_xbot != w->w_surfaceArea.r_xbot)
	|| (crec->dbw_surfaceArea.r_ybot != w->w_surfaceArea.r_ybot)
	|| (crec->dbw_surfaceArea.r_xtop != w->w_surfaceArea.r_xtop)
	|| (crec->dbw_surfaceArea.r_ytop != w->w_surfaceArea.r_ytop))
    {
	/* The window has changed size or position or scale,
	 * so update measurements on label size in this window.
	 * Also, pick a size for labels based on the scale in
	 * half the window:  the idea is to make the labels about
	 * half the height of typical wires.
	 */
	int halfWireWidth;
	Rect text;

	halfWireWidth = MAX(RtrMetalWidth, RtrPolyWidth);
	halfWireWidth = (halfWireWidth * w->w_scale) >> (SUBPIXELBITS + 1);
	for (i = GR_TEXT_XLARGE; i >= GR_TEXT_SMALL; i--)
	{
	    GrLabelSize("B", GEO_CENTER, i, &text);
	    if (halfWireWidth > (text.r_ytop - text.r_ybot)) break;
	}
	if (i < GR_TEXT_SMALL) i = GR_TEXT_SMALL;
	if ((3 * halfWireWidth) <= (text.r_ytop - text.r_ybot))
	    crec->dbw_labelSize = -lambdasPerPixel;
	else crec->dbw_labelSize = i;

	crec->dbw_expandAmounts.r_xbot = 0;
	crec->dbw_expandAmounts.r_ybot = 0;
	crec->dbw_expandAmounts.r_xtop = 0;
	crec->dbw_expandAmounts.r_ytop = 0;

	crec->dbw_origin = w->w_origin;
	crec->dbw_scale = w->w_scale;
	crec->dbw_surfaceArea = w->w_surfaceArea;
    }

    /* Labels can stick out a long way from the point they are
     * anchored to.  In the code that draws labels we record the
     * size (in pixels) of the largest label in the window.  Here
     * we use that information to increase the size of the search
     * area for labels enough to be sure we'll see any label that
     * falls partially or completely in the area we're redisplaying.
     * Note:  we have to also include the size of the label cross
     * in the area to be redisplayed.
     */

    labelArea = largerArea;
    (void) GeoInclude(&GrCrossRect, &crec->dbw_expandAmounts);
    if (pixelsPerLambda > 0)
    {
	labelArea.r_xtop -=
		ceilDiv(crec->dbw_expandAmounts.r_xbot, pixelsPerLambda);
	labelArea.r_ytop -=
		ceilDiv(crec->dbw_expandAmounts.r_ybot, pixelsPerLambda);
	labelArea.r_xbot -=
		ceilDiv(crec->dbw_expandAmounts.r_xtop, pixelsPerLambda);
	labelArea.r_ybot -=
		ceilDiv(crec->dbw_expandAmounts.r_ytop, pixelsPerLambda);
    }
    else
    {
	labelArea.r_xtop -= crec->dbw_expandAmounts.r_xbot * lambdasPerPixel;
	labelArea.r_ytop -= crec->dbw_expandAmounts.r_ybot * lambdasPerPixel;
	labelArea.r_xbot -= crec->dbw_expandAmounts.r_xtop * lambdasPerPixel;
	labelArea.r_ybot -= crec->dbw_expandAmounts.r_ytop * lambdasPerPixel;
    }

    /**
    TxPrintf("Need to expand area by (%d %d) (%d %d) pixels.\n",
	crec->dbw_expandAmounts.r_xbot,
	crec->dbw_expandAmounts.r_ybot,
	crec->dbw_expandAmounts.r_xtop,
	crec->dbw_expandAmounts.r_ytop);
    **/

    /* Set the clipping rectangle to contain only the area being displayed. */

    dbwWindow = w;
    windClip = w->w_screenArea;
    WindSurfaceToScreen(w, rootArea, &rootClip);
    GrClipTo(&rootClip);

    scontext.scx_area = largerArea;
    scontext.scx_use = ((CellUse *)w->w_surfaceID);
    scontext.scx_x = scontext.scx_y = -1;
    scontext.scx_trans = GeoIdentityTransform;
    bitMask = crec->dbw_bitmask;

    /* See if this window contains the edit cell.  If so, remember
     * information about the edit cell so we can identify it during
     * the action routines.
     */

    if (cellDef == EditRootDef)
    {
        editDef = EditCellUse->cu_def;
	editTrans = EditToRootTransform;
    }
    else editDef = NULL;
    if (crec->dbw_flags & DBW_ALLSAME) dbwAllSame = TRUE;
    else dbwAllSame = FALSE;

    /* Empty the area of all previous info. */

    GrClipBox(&rootClip, STYLE_ERASEALL);

    /* Go through all of the tile display styles.  For each
     * style, if there are tiles that include that style, then
     * find and display all the tiles.
     *
     * We use the fast version of GrClipBox in the filter
     * function, GrFastBox.  To use it requires that we set
     * the style before the call, which we do inside of
     * dbwPaintFunc() on the first box displayed for each
     * style.
     *
     * Unlock the window before the following loop to avoid
     * holding the lock too long.
     */
    GrUnlock(w);
    dbwLockW = w;
    dbwIsLocked = FALSE;
    for (i = 0; i < DBWNumStyles; i++)
    {
	mask = DBWStyleToTypes(i);
	TTMaskAndMask3(&layers, mask, &crec->dbw_visibleLayers);
	if (!TTMaskIsZero(&layers))
	{
	    TileType t, s;
	    TileTypeBitMask *rMask;

	    /* For each contact type, if the contact is not visible,	*/
	    /* display any of its residue layers that are visible.	*/

	    for (t = TT_TECHDEPBASE; t < DBNumTypes; t++)
		if (DBIsContact(t))
		    if (!TTMaskHasType(&layers, t))
		    {
			rMask = DBResidueMask(t);
			if (TTMaskIntersect(rMask, &layers))
			    TTMaskSetType(&layers, t);
		    }

	    /* Treat any stacking type in the mask like the	*/
	    /* residue type whose home plane is the same as	*/
	    /* the home plane of the stacking type.		*/

	    for (t = TT_TECHDEPBASE; t < DBNumUserLayers; t++)
		if (TTMaskHasType(&layers, t))
		    for (s = DBNumUserLayers; s < DBNumTypes; s++)
		    {
			rMask = DBResidueMask(s);
			if (TTMaskHasType(&layers, s) &&
				TTMaskHasType(rMask, t))
			    if (DBPlane(s) != DBPlane(t))
				TTMaskClearType(&layers, s);
		    }

	    /*
	     * To avoid holding a lock for too long, we don't set it
	     * until we actually see something to display, and we
	     * clear it immediately after we've displayed a style
	     * that had something in it.
	     */
	    disStyle = i + TECHBEGINSTYLES;
	    disWasPale = FALSE;		/* Using normal solid style */
	    dbwNeedStyle = TRUE;	/* Haven't set style yet */
	    if (DBTreeSrUniqueTiles(&scontext, &layers, bitMask,
		    dbwPaintFunc, (ClientData) NULL))
	    {
		/* We were interrupted.  If we deal with backing store,	*/
		/* it must be invalidated.				*/
		if (GrFreeBackingStorePtr != NULL)
		    (*GrFreeBackingStorePtr)(w);
	    }

	    if (dbwIsLocked)
	    {
		GrUnlock(w);
		dbwIsLocked = FALSE;
	    }
	}
    }

    GrLock(w, TRUE);
    GrClipTo(&rootClip);

    /* Now, find any labels that are visible and display them.
     * Label text is only displayed for certain ranges of magnification:
     * If a window is too zoomed-out, then text redisplay takes too
     * long and just clutters up the screen anyway.  For displaying
     * labels, we set the clip area to the whole screen (otherwise
     * new labels will be clipped to just the paint area).  This only
     * works because (a) graphics clips down to the window's actual
     * displayed area anyway, and (b) labels are opaque layers on top
     * of everything else (otherwise there might be color mixing
     * problems).
     */

    if (crec->dbw_flags & DBW_SEELABELS)
    {
	scontext.scx_area = labelArea;

	/* make sure that we are searching an area, not just a point */
	scontext.scx_area.r_xtop = MAX(scontext.scx_area.r_xtop,
		scontext.scx_area.r_xbot + 1);
	scontext.scx_area.r_ytop = MAX(scontext.scx_area.r_ytop,
		scontext.scx_area.r_ybot + 1);
	dbwLabelSize = crec->dbw_labelSize;
	dbwExpandAmounts = &crec->dbw_expandAmounts;
	GrClipTo(&GrScreenRect);

        /* Set style information beforehand */
        GrSetStuff(STYLE_LABEL);
	(void) DBTreeSrLabels(&scontext, &DBAllTypeBits, bitMask,
		(TerminalPath *) NULL,
		TF_LABEL_DISPLAY | TF_LABEL_ATTACH | TF_LABEL_REVERSE_SEARCH,
		dbwLabelFunc, (ClientData)(&crec->dbw_visibleLayers));
	GrClipTo(&rootClip);
    }

    /* Next, display the bounding boxes that are visible.  Before doing
     * this, calculate the area occupied by the text "BBB".  A cell won't
     * get its id or name displayed unless its bbox is at least this
     * large.
     */

    if (crec->dbw_flags & DBW_SEECELLS)
    {
	GrLabelSize("BBB", GEO_CENTER, GR_TEXT_SMALL, &dbwMinBBox);
	dbwMinBBox.r_xtop -= dbwMinBBox.r_xbot;
	dbwMinBBox.r_ytop -= dbwMinBBox.r_ybot;

	/* Redisplay cell names as if the whole window were visible.
	 * This must be done since we slide the names around to fit
	 * into the clip area.  Set the style beforehand for speed.
	 */

	GrClipTo(&GrScreenRect); /* Will be cut down to window size by
				  * the graphics module.
				  */
	scontext.scx_area = largerArea;
	GrSetStuff(STYLE_BBOX);
	(void) DBTreeSrCells(&scontext, bitMask, dbwBBoxFunc, (ClientData)NULL);
	GrClipTo(&rootClip);
    }

    /* Now redisplay the grid.  This code is a bit tricky because
     * it makes sure that the origin ends up on a grid line.
     */

    if (crec->dbw_flags & DBW_GRID)
    {
	int width, height;
	Rect gridRect;

	/* Compute a grid template rectangle, in screen coordinates, that
	 * is near the lower-left corner of the window.
	 */

	gridRect.r_ll = w->w_origin;
	width = crec->dbw_gridRect.r_xtop - crec->dbw_gridRect.r_xbot;
	height = crec->dbw_gridRect.r_ytop - crec->dbw_gridRect.r_ybot;
	gridRect.r_xbot -= w->w_scale *
		((w->w_surfaceArea.r_xbot - crec->dbw_gridRect.r_xbot) % width);
	gridRect.r_ybot -= w->w_scale *
		((w->w_surfaceArea.r_ybot - crec->dbw_gridRect.r_ybot) % height);
	gridRect.r_xtop = gridRect.r_xbot + w->w_scale*width;
	gridRect.r_ytop = gridRect.r_ybot + w->w_scale*height;
	GrClipBox(&gridRect, STYLE_GRID);

	/* Redisplay a little square around the origin for the edit cell
	 * (if the edit cell is in this window).  Make the origin 4 pixels
	 * across, but don't display it unless this is less than two lambda
	 * units.  That way, we always know how much to redisplay (in lambda
	 * units), when the edit cell changes.
	 */

	if (editDef != NULL)
	{
	    Rect r, r2;
	    r.r_xbot = r.r_ybot = -1;
	    r.r_xtop = r.r_ytop = 1;
	    WindSurfaceToScreen(w, &r, &r2);
	    if ((r2.r_xtop - r2.r_xbot) >= 4)
	    {
		GeoTransRect(&EditToRootTransform, &GeoNullRect, &r2);
		WindSurfaceToScreen(w, &r2, &r);
		r.r_xbot -= 2;
		r.r_xtop += 2;
		r.r_ybot -= 2;
		r.r_ytop += 2;
		GrClipBox(&r, STYLE_ORIGIN);
	    }
	}
    }

    /* If there is a tile plane being "watched", redisplay
     * its structure.
     */

    if (crec->dbw_watchPlane >= 0)
    {
	Transform toCell;

	GeoInvertTrans(&crec->dbw_watchTrans, &toCell);
	GeoTransRect(&toCell, &w->w_surfaceArea, &dbwWatchArea);
	dbwWatchArea.r_xbot -= lambdasPerPixel;
	dbwWatchArea.r_xtop += lambdasPerPixel;
	dbwWatchArea.r_ybot -= lambdasPerPixel;
	dbwWatchArea.r_ytop += lambdasPerPixel;
	dbwWatchTrans = crec->dbw_watchTrans;
        dbwWatchDemo = ((crec->dbw_flags & DBW_WATCHDEMO) != 0);
	dbwSeeTypes = ((crec->dbw_flags & DBW_SEETYPES) != 0);
	(void) DBSrPaintArea((Tile *) NULL,
	    crec->dbw_watchDef->cd_planes[crec->dbw_watchPlane],
	    &dbwWatchArea, &DBAllTypeBits, dbwTileFunc, (ClientData) NULL);
    }

    /* Record information so that the highlight manager will redisplay
     * highlights over the area we just redisplayed.
     */

    DBPaintPlane(crec->dbw_hlRedraw, &labelArea,
	    DBStdPaintTbl(TT_ERROR_P, PL_DRC_ERROR),
	    (PaintUndoInfo *) NULL);

    /* display a debugging box which shows which area should be redrawn */
    if (debugit)
    {
	WindSurfaceToScreen(w, &largerArea, &screenArea);
	(void) GrClipBox(&screenArea, STYLE_LABEL);
    }

#ifdef	notdef
    /* finally, display the plowing debugging information */
    cmdPlowDisplayEdges(w, rootArea, clipArea);
#endif	/* notdef */

    GrUnlock(w);

    /* Create backing store of this area for quick refresh of highlight */
    /* areas.								*/

    if (GrPutBackingStorePtr != NULL)
	(*GrPutBackingStorePtr)(w, &rootClip);
}

/*
 * ----------------------------------------------------------------------------
 *
 * dbwPaintFunc --
 *
 * 	Invoked by database searching routines during redisplay to
 *	draw a tile on the screen.
 *
 * Results:
 *	Always returns 0 to keep the search from aborting.
 *
 * Side effects:
 *	Clips and draws a paint tile.
 *
 * ----------------------------------------------------------------------------
 */

int
dbwPaintFunc(
    Tile *tile,			/* Tile to be redisplayed. */
    TileType dinfo,		/* Split tile information */
    TreeContext *cxp)		/* From DBTreeSrTiles */
{
    SearchContext *scx = cxp->tc_scx;
			/* Contains pointer to use containing def
			 * in which tile appears, and transform to
			 * screen coordinates.
			 */

#ifdef MAGIC_WRAPPER
    /* This allows the display to be interrupted when running Tcl/Tk.	*/
    /* Because graphics are not handled by a separate process, the	*/
    /* drawing routine itself is responsible for periodically checking	*/
    /* the graphics event queue to see if something is pending.		*/

    if (GrDisplayStatus == DISPLAY_BREAK_PENDING)
    {
	GrDisplayStatus = DISPLAY_IN_PROGRESS;
	if (GrEventPendingPtr)
	{
	    if ((*GrEventPendingPtr)())
		sigOnInterrupt(0);
	    else
		SigSetTimer(0);
	}
    }
#endif

    /* Ignore DRC error tiles in anything but the top-level window */
    if (scx->scx_use != (CellUse *)dbwWindow->w_surfaceID)
    {
	TileType ttype = TiGetType(tile);
	if (ttype == TT_ERROR_P || ttype == TT_ERROR_S || ttype == TT_ERROR_PS)
	    return 0;
    }

    if (!dbwIsLocked)
    {
	GrLock(dbwLockW, TRUE);
	GrClipTo(&rootClip);
	dbwIsLocked = TRUE;
    }
    if (dbwNeedStyle)
    {
	GrSetStuff(disStyle);
	dbwNeedStyle = FALSE;
    }

    /* If this isn't the edit cell, add 64 to the display style
     * to be used.
     */

    if (!dbwAllSame && ((editDef != scx->scx_use->cu_def)
	|| (scx->scx_trans.t_a != editTrans.t_a)
	|| (scx->scx_trans.t_b != editTrans.t_b)
	|| (scx->scx_trans.t_c != editTrans.t_c)
	|| (scx->scx_trans.t_d != editTrans.t_d)
	|| (scx->scx_trans.t_e != editTrans.t_e)
	|| (scx->scx_trans.t_f != editTrans.t_f)))
    {
	if (!disWasPale)
	{
	    GrSetStuff(disStyle + DBWNumStyles);
	    disWasPale = TRUE;
	}
    }
    else
    {
	if (disWasPale)
	{
	    GrSetStuff(disStyle);
	    disWasPale = FALSE;
	}
    }

    /* Note:  GrFastBox() has been replaced here with GrBox(). 	*/
    /* This checks for non-square outlines before deciding	*/
    /* whether to render the outline with a fast rectangle-	*/
    /* drawing routine or to render it segment by segment.	*/

    GrBox(dbwWindow, &scx->scx_trans, tile, dinfo);
    return 0;
}


/*
 * ----------------------------------------------------------------------------
 *
 * DBWDrawLabel --
 *
 * 	This procedure does all the work of actually drawing labels
 * 	on the screen.  It is invoked by label redisplay code and also
 *	by the selection redisplay code.
 *
 * Results:
 *	None.
 *
 * Side effects:
 *	The label given by text, rect, and pos is drawn on the screen
 *	in style "style" and size "labelSize".  The caller must have set
 *	up all of the clipping information for the window in which the
 *	label is to be drawn.  This procedure updates sizeBox to be
 *	large enough to hold the total pixel area occupied by the label
 *	(assuming it were drawn at (0,0)).
 *
 * ----------------------------------------------------------------------------
 */

void
DBWDrawLabel(
    Label *label,		/* Text to be displayed. */
    Rect *rect,			/* labrect, clipped to the visible window
				 */
    int pos,			/* Position of text relative to rect (e.g.
				 * GEO_NORTH) in screen coordinates.
				 */
    int style,                 /* Style to use for redisplay; if -1 then
                                * this has already been set by the caller
                                * and we shouldn't call GrSetStuff.
                                */
    int labelSize,		/* Size to use for drawing labels.  If < 0 then
				 * no text is drawn:  only the box.
				 */
    Rect *sizeBox)		/* Expanded if necessary to include the
				 * screen area of the text for this label.
				 */
{
    Point p;
    Rect location;
    char *text = label->lab_text;
    int result;

    if (style >= 0) GrSetStuff(style);
    GrDrawFastBox(rect, labelSize);
    if (labelSize < 0) return;

    switch (pos)
    {
	case GEO_CENTER:
	    p.p_x = (rect->r_xbot + rect->r_xtop)/2;
	    p.p_y = (rect->r_ybot + rect->r_ytop)/2;
	    break;
	case GEO_NORTH:
	    p.p_x = (rect->r_xbot + rect->r_xtop)/2;
	    p.p_y = rect->r_ytop;
	    break;
	case GEO_NORTHEAST:
	    p = rect->r_ur;
	    break;
	case GEO_EAST:
	    p.p_x = rect->r_xtop;
	    p.p_y = (rect->r_ybot + rect->r_ytop)/2;
	    break;
	case GEO_SOUTHEAST:
	    p.p_x = rect->r_xtop;
	    p.p_y = rect->r_ybot;
	    break;
	case GEO_SOUTH:
	    p.p_x = (rect->r_xbot + rect->r_xtop)/2;
	    p.p_y = rect->r_ybot;
	    break;
	case GEO_SOUTHWEST:
	    p = rect->r_ll;
	    break;
	case GEO_WEST:
	    p.p_x = rect->r_xbot;
	    p.p_y = (rect->r_ybot + rect->r_ytop)/2;
	    break;
	case GEO_NORTHWEST:
	    p.p_x = rect->r_xbot;
	    p.p_y = rect->r_ytop;
	    break;
    }
    if (GrPutText(text, style, &p, pos, labelSize, FALSE,
			&GrScreenRect, &location))
    {
	sizeBox->r_xbot = MIN(sizeBox->r_xbot, location.r_xbot - p.p_x);
	sizeBox->r_ybot = MIN(sizeBox->r_ybot, location.r_ybot - p.p_y);
	sizeBox->r_xtop = MAX(sizeBox->r_xtop, location.r_xtop - p.p_x);
	sizeBox->r_ytop = MAX(sizeBox->r_ytop, location.r_ytop - p.p_y);
    }
}

/*
 * ----------------------------------------------------------------------------
 *
 * DBWDrawFontLabel --
 *
 *	This procedure is like DBWDrawLabel but handles rendered font
 *	labels.  It is invoked by the label redisplay code in dbwind
 *	and select.  Unlike DBWDrawLabel, it does all the layout-to-screen
 *	transformations itself.
 *
 * Results:
 *	None.
 *
 * Side effects:
 *	The label given by text, rect, and pos is drawn on the screen
 *	in style "style" and size "labelSize".  The caller must have set
 *	up all of the clipping information for the window in which the
 *	label is to be drawn.  This procedure updates sizeBox to be
 *	large enough to hold the total pixel area occupied by the label
 *	(assuming it were drawn at (0,0)).
 *
 * ----------------------------------------------------------------------------
 */

void
DBWDrawFontLabel(
    Label *label,
    MagWindow *window,
    Transform *trans,
    int style)		/* If -1, style is already set */
{
    Point *p, newcorner, scrncorners[4], labOrigin;
    Rect rootArea, labrect;
    int i, rotate, minv, scaledLambdasPerPixel;
    dlong tmp, dval, scale;
    double rads;

    GeoTransRect(trans, &label->lab_rect, &rootArea);
    WindSurfaceToScreen(window, &rootArea, &labrect);
    labOrigin.p_x = (rootArea.r_xbot + rootArea.r_xtop) << 2;
    labOrigin.p_y = (rootArea.r_ybot + rootArea.r_ytop) << 2;

    /* This bit of code sets the scale for the "cross" associated with	*/
    /* a label as a logarithmic function of the window scale.  This is	*/
    /* completely subjective, but seems to produce a decent result.	*/

    scaledLambdasPerPixel = 0;
    i = (SUBPIXEL / window->w_scale);
    while (i != 0)
    {
	i >>= 1;
	scaledLambdasPerPixel++;
    }

    if (style >= 0) GrSetStuff(style);
    GrDrawFastBox(&labrect, -scaledLambdasPerPixel);

    for (i = 0; i < 4; i++)
    {
	GeoTransPointDelta(trans, &label->lab_corners[i], &newcorner);

	/* Effectively, WindPointToScreen(), but with an	*/
	/* extra scalefactor of 8, including computing the 	*/
	/* (unclipped) origin from the center of rootArea.	*/

	tmp = labOrigin.p_x + newcorner.p_x;
	tmp -= (dlong)window->w_surfaceArea.r_xbot << 3;
	dval = ((dlong)window->w_origin.p_x << 3) + (dlong)(tmp * window->w_scale);
	scrncorners[i].p_x = (int)(dval >> (SUBPIXELBITS + 3));

	tmp = labOrigin.p_y + newcorner.p_y;
	tmp -= (dlong)window->w_surfaceArea.r_ybot << 3;
	dval = ((dlong)window->w_origin.p_y << 3) + (dlong)(tmp * window->w_scale);
	scrncorners[i].p_y = (int)(dval >> (SUBPIXELBITS + 3));
    }

    /* Ensure that the label is always drawn with text upright.	*/
    /* Compute rotation from the transformed baseline angle.	*/
    /* (The "2" is a slop factor to account for round-off error	*/
    /* in the computation of scrncorners.)			*/

    rotate = GeoTransAngle(trans, label->lab_rotate);
    if ((rotate >= 0 && rotate < 90) || (rotate >= 180 && rotate < 270))
    {
	/* Startpoint is the bottommost point.   Due to roundoff error,	*/
	/* we need to watch closely when the angle is close to a	*/
	/* multiple of 90 degrees.					*/

	minv = scrncorners[0].p_y;
	p = &scrncorners[0];
	for (i = 1; i < 4; i++)
	{
	    if ((scrncorners[i].p_y - 2) < minv)
	    {
		if ((scrncorners[i].p_y + 2) > minv)
		{
		    if (((rotate < 5) || (rotate >= 180 && rotate < 185)) &&
				(scrncorners[i].p_x > p->p_x))
			continue;
		    if (((rotate > 85 && rotate < 90) || (rotate > 265)) &&
				(scrncorners[i].p_x < p->p_x))
			continue;
		}
		minv = scrncorners[i].p_y;
		p = &scrncorners[i];
	    }
	}
    }
    else
    {
	/* startpoint is the leftmost point */
	minv = scrncorners[0].p_x;
	p = &scrncorners[0];
	for (i = 1; i < 4; i++)
	{
	    if ((scrncorners[i].p_x - 2) < minv)
	    {
		if ((scrncorners[i].p_x + 2) > minv)
		{
		    if (((rotate < 95) || (rotate >= 270 && rotate < 275)) &&
				(scrncorners[i].p_y < p->p_y))
			continue;
		    if (((rotate > 175 && rotate < 180) || (rotate > 355)) &&
				(scrncorners[i].p_y > p->p_y))
			continue;
		}
		minv = scrncorners[i].p_x;
		p = &scrncorners[i];
	    }
	}
    }
    if (rotate >= 90 && rotate < 270)
    {
	rotate += 180;
	if (rotate >= 360) rotate -= 360;
    }

    scale = ((dlong)window->w_scale * (dlong)label->lab_size) >> (SUBPIXELBITS + 3);

    if (scale > 0)
    {
	GrFontText(label->lab_text, style, p, label->lab_font,
			(int)scale, rotate, &GrScreenRect);
    }
}


/*
 * ----------------------------------------------------------------------------
 *
 * dbwLabelFunc --
 *
 * 	Called by database searching routines during redisplay.  It
 *	displays a label on the screen.
 *
 * Results:
 *	Always returns 0 to keep the search from aborting.
 *
 * Side effects:
 *	The label is clipped and drawn on the screen.
 *
 * ----------------------------------------------------------------------------
 */

int
dbwLabelFunc(
    SearchContext *scx,		/* Contains pointer to use containing def in
				 * which label appears, and transform to
				 * screen coordinates.
				 */
    Label *label,		/* Label to be displayed. */
    TerminalPath *tpath,	/* Contains pointer to full pathname of label */
    ClientData clientData)	/* Used for mask for dbw_visibleLayers */
{
    Rect labRect, tmp;
    int screenPos, screenRot, newStyle;
    TileTypeBitMask *vmask;

    vmask = (TileTypeBitMask *)clientData;

    /* Do not draw the label if the layer to which it is attached is
     * not being drawn.
     */
    if (!TTMaskHasType(vmask, label->lab_type))
	return 0;

    if (!dbwAllSame && ((editDef != scx->scx_use->cu_def)
	|| (scx->scx_trans.t_a != editTrans.t_a)
	|| (scx->scx_trans.t_b != editTrans.t_b)
	|| (scx->scx_trans.t_c != editTrans.t_c)
	|| (scx->scx_trans.t_d != editTrans.t_d)
	|| (scx->scx_trans.t_e != editTrans.t_e)
	|| (scx->scx_trans.t_f != editTrans.t_f)))
	disWasPale = TRUE;
    else
	disWasPale = FALSE;

    if (label->lab_flags & PORT_DIR_MASK)
	newStyle = (disWasPale) ? STYLE_PORT_PALE : STYLE_PORT;
    else
	newStyle = (disWasPale) ? STYLE_LABEL_PALE : STYLE_LABEL;

    if (newStyle != disStyle)
    {
	disStyle = newStyle;
        GrSetStuff(newStyle);
    }

    if (label->lab_font < 0)
    {
	screenPos = GeoTransPos(&scx->scx_trans, label->lab_just);
	GeoTransRect(&scx->scx_trans, &label->lab_rect, &tmp);
	WindSurfaceToScreen(dbwWindow, &tmp, &labRect);
	if (!GEO_TOUCH(&labRect, &dbwWindow->w_screenArea)) return 0;
	DBWDrawLabel(label, &labRect, screenPos, -1, dbwLabelSize, dbwExpandAmounts);
    }
    else
    {
	DBWDrawFontLabel(label, dbwWindow, &scx->scx_trans, -1);
    }

    if (label->lab_flags & PORT_DIR_MASK)
    {
	if (label->lab_font >= 0)	// If not done already. . .
	{
	    screenPos = GeoTransPos(&scx->scx_trans, label->lab_just);
	    GeoTransRect(&scx->scx_trans, &label->lab_rect, &tmp);
	}
	WindSurfaceToScreenNoClip(dbwWindow, &tmp, &labRect);

	/* Temporarily set the style for port connection lines */
        GrSetStuff(STYLE_PORT_CONNECT);
	if (label->lab_flags & PORT_DIR_NORTH)
	    GrClipLine(labRect.r_xbot, labRect.r_ytop,
			labRect.r_xtop, labRect.r_ytop);
	if (label->lab_flags & PORT_DIR_SOUTH)
	    GrClipLine(labRect.r_xbot, labRect.r_ybot,
			labRect.r_xtop, labRect.r_ybot);
	if (label->lab_flags & PORT_DIR_EAST)
	    GrClipLine(labRect.r_xtop, labRect.r_ybot,
			labRect.r_xtop, labRect.r_ytop);
	if (label->lab_flags & PORT_DIR_WEST)
	    GrClipLine(labRect.r_xbot, labRect.r_ybot,
			labRect.r_xbot, labRect.r_ytop);
        GrSetStuff(disStyle);
    }
    return 0;
}

/*
 * ----------------------------------------------------------------------------
 *
 * dbwBBoxFunc --
 *
 * 	Called by database searching routines during redisplay.
 *      The caller should have already set the style information.
 *
 * Results:
 *	Always returns 0 to keep the search from aborting.
 *
 * Side effects:
 *	The bounding box of the cell is clipped and drawn on the screen,
 *	along with the name and id of the celluse.  The bounding box
 *	area is returned in the pointer argument "sizeBox".
 *
 * ----------------------------------------------------------------------------
 */

int
dbwBBoxFunc(
    SearchContext *scx)	 /* Describes context of cell. */
{
    Rect r, r2;
    char idName[100];
    Point p;
    CellUse *cellUse;

    cellUse = scx->scx_use;
    GeoTransRect(&scx->scx_trans, &cellUse->cu_def->cd_bbox, &r2);
    WindSurfaceToScreen(dbwWindow, &r2, &r);
    GrFastBox(&r);

    /* Don't futz around with text if the bbox is tiny. */

    if (((r.r_xtop-r.r_xbot) < dbwMinBBox.r_xtop)
	|| ((r.r_ytop-r.r_ybot) < dbwMinBBox.r_ytop)) return 0;

    p.p_x = (r.r_xbot + r.r_xtop)/2;
    p.p_y = (r.r_ybot + 2*r.r_ytop)/3;
    GeoClip(&r, &windClip);

    GrPutText(cellUse->cu_def->cd_name, -1, &p,
		GEO_CENTER, GR_TEXT_LARGE, TRUE, &r, (Rect *) NULL);

    (void) DBPrintUseId(scx, idName, 100, TRUE);
    p.p_y = (2*r.r_ybot + r.r_ytop)/3;
    GrPutText(idName, -1, &p, GEO_CENTER,
        GR_TEXT_LARGE, TRUE, &r, (Rect *)NULL);
    return 0;
}

/*
 * ----------------------------------------------------------------------------
 *
 * dbwTileFunc --
 *
 * 	Called by the database search routines, from DBWredisplay
 *	during redisplay.
 *
 * Results:
 *	Always returns 0 to keep the search from aborting.
 *
 * Side effects:
 *	Displays a tile's bounding box and corner stitches.
 *
 * ----------------------------------------------------------------------------
 */

int
dbwTileFunc(
    Tile *tile,				/* A tile to be redisplayed. */
    TileType dinfo,			/* Split tile information (unused) */
    ClientData clientdata)		/* (unused) */
{
    Rect r, r2;
    int xoffset, yoffset;
    Point p;
    Point pLL, pUR;
    Tile *stitch;
    char string[20];
    int i, pos;

    TiToRect(tile, &r2);

    /* Some of the tiles have "infinite sizes", which we have to clip
     * in order to avoid numerical problems.
     */

    GeoClip(&r2, &dbwWatchArea);
    pLL = r2.r_ll;
    pUR = r2.r_ur;
    GeoTransRect(&dbwWatchTrans, &r2, &r);
    WindSurfaceToScreen(dbwWindow, &r, &r2);

    /* Draw the tile, then put up text for the tile's address and
     * stitches.
     */

    (void) GrClipBox(&r2, STYLE_DRAWTILE);
    GeoTransPoint(&dbwWatchTrans, &pLL, &p);
    WindPointToScreen(dbwWindow, &p, &pLL);
    GeoTransPoint(&dbwWatchTrans, &pUR, &p);
    WindPointToScreen(dbwWindow, &p, &pUR);
    GeoClipPoint(&pLL, &rootClip);
    GeoClipPoint(&pUR, &rootClip);


    if (dbwSeeTypes)
    {
    	 (void) sprintf(string, "%s", DBTypeShortName(TiGetType(tile)));
    }
    else
    {
	(void) sprintf(string, "%p", (void *) tile);
    }

    GeoClip(&r2, &rootClip);
    p.p_x = (r2.r_xbot + r2.r_xtop)/2;
    p.p_y = (r2.r_ybot + r2.r_ytop)/2;
    if (!dbwWatchDemo || dbwSeeTypes)
	GrPutText(string, STYLE_DRAWTILE, &p, GEO_CENTER,
	    GR_TEXT_LARGE, FALSE, &r2, (Rect *) NULL);

#define	XYOFFSET	12

    for (i = 0; i < 4; i++)
    {
	xoffset = 0;
	yoffset = 0;
	switch (i)
	{
	    case 0:
		stitch = BL(tile);
		p = pLL;
		yoffset = XYOFFSET;
		pos = GEO_NORTHEAST;
		break;
	    case 1:
		stitch = LB(tile);
		p = pLL;
		xoffset = XYOFFSET;
		pos = GEO_NORTHEAST;
		break;
	    case 2:
		stitch = RT(tile);
		p = pUR;
		xoffset = -XYOFFSET;
		pos = GEO_SOUTHWEST;
		break;
	    case 3:
		stitch = TR(tile);
		p = pUR;
		yoffset = -XYOFFSET;
		pos = GEO_SOUTHWEST;
		break;
	}

	pos = GeoTransPos(&dbwWatchTrans, pos);

	if (dbwWatchTrans.t_a == 0)
	{
	    /* a rotation by 90 or 270 */
	    int temp;
	    temp = xoffset;
	    xoffset = yoffset;
	    yoffset = temp;
	}

	if ((dbwWatchTrans.t_a < 0) || (dbwWatchTrans.t_b < 0))
	{
	    /* mirror in x */
	    xoffset = -xoffset;
	}

	if ((dbwWatchTrans.t_d < 0) || (dbwWatchTrans.t_e < 0))
	{
	    /* mirror in y */
	    yoffset = -yoffset;
	}

	p.p_x += xoffset;
	p.p_y += yoffset;
	if (dbwWatchDemo)
	{
	    Rect stick, head, head2;
	    stick.r_ll = p;
	    stick.r_ur = p;
#define TAIL	5
#define HEAD	9
	    switch (i)
	    {
		case 0:
		    stick.r_xbot -= HEAD;
		    stick.r_xtop += TAIL;
		    head = stick;
		    head.r_xbot++;
		    head.r_xtop = head.r_xbot;
		    head.r_ytop++;
		    head.r_ybot--;
		    head2 = head;
		    head2.r_xbot++;
		    head2.r_xtop++;
		    head2.r_ytop++;
		    head2.r_ybot--;
		    break;
		case 1:
		    stick.r_ybot -= HEAD;
		    stick.r_ytop += TAIL;
		    head = stick;
		    head.r_ybot++;
		    head.r_ytop = head.r_ybot;
		    head.r_xtop++;
		    head.r_xbot--;
		    head2 = head;
		    head2.r_xbot--;
		    head2.r_xtop++;
		    head2.r_ytop++;
		    head2.r_ybot++;
		    break;
		case 2:
		    stick.r_ybot -= TAIL;
		    stick.r_ytop += HEAD;
		    head = stick;
		    head.r_ytop--;
		    head.r_ybot = head.r_ytop;
		    head.r_xtop++;
		    head.r_xbot--;
		    head2 = head;
		    head2.r_xbot--;
		    head2.r_xtop++;
		    head2.r_ytop--;
		    head2.r_ybot--;
		    break;
		case 3:
		    stick.r_xbot -= TAIL;
		    stick.r_xtop += HEAD;
		    head = stick;
		    head.r_xtop--;
		    head.r_xbot = head.r_xtop;
		    head.r_ytop++;
		    head.r_ybot--;
		    head2 = head;
		    head2.r_xbot--;
		    head2.r_xtop--;
		    head2.r_ytop++;
		    head2.r_ybot--;
		    break;
	    }
	    GrClipBox(&stick, STYLE_LABEL);
	    GrClipBox(&head, STYLE_LABEL);
	    GrClipBox(&head2, STYLE_LABEL);
	}
	else if (!dbwSeeTypes)
	{
	    (void) sprintf(string, "%p", (void *) stitch);
	    GrPutText(string, STYLE_DRAWTILE, &p, pos,
		GR_TEXT_SMALL, FALSE, &r2, (Rect *) NULL);
	}
    }
    return 0;
}


/*
 * ----------------------------------------------------------------------------
 *	DBWAreaChanged --
 *
 * 	Invoked to remind us that a certain piece of a certain cell
 *	has been modified and must eventually be redisplayed.
 *
 * Results:
 *	None.
 *
 * Side effects:
 *	Information is remembered, so that when WindUpdate is called
 *	the area will be redisplayed in every window where it appears.
 *
 * ----------------------------------------------------------------------------
 */

static TileTypeBitMask *dbwLayersChanged;
				/* DBWAreaChanged's "layers" parameter. */

void
DBWAreaChanged(
    CellDef *cellDef,		/* The cell definition that was modified. */
    Rect *defArea,		/* The area of the definition that changed. */
    int expandMask,		/* We're only interested these windows.
				 * Use DBW_ALLWINDOWS for all windows.
				 */
    TileTypeBitMask *layers)	/* Indicates which layers were modified.  If
				 * NULL, it means that labels were deleted
				 * from defArea in addition to paint.  We'll
				 * have to redisplay a larger area in order
				 * to fully erase labels that used to stick
				 * out from defArea.  NULL is used when
				 * subcells are unexpanded or moved for
				 * example.  NULL is the most inclusive option
				 * (does everything that &DBAllButSpaceBits
				 * does and more), and should be used whenever
				 * you're not sure what to do.  Note:  it's
				 * normally better to use DBWLabelChanged when
				 * individual labels are modified;  the NULL
				 * option is for when large numbers of labels
				 * have potentially been modified.
				 */
{
    Rect newArea;		/* Corresponding area in parent. */
    int newMask;		/* Windows we're interested in in parent. */
    int x, y, xlo, ylo;		/* Array indices. */
    int xhi, yhi;
    Rect tmp;
    CellUse *use;

    if ((defArea->r_xbot == defArea->r_xtop)
	|| (defArea->r_ybot == defArea->r_ytop)) return;

    /**
    TxPrintf("Cell %s, area (%d, %d) (%d, %d) changed, mask %d.\n",
	    cellDef->cd_name,  defArea->r_xbot, defArea->r_ybot,
	    defArea->r_xtop, defArea->r_ytop, expandMask);
    **/

    /* Don't permit signals to interrupt us here. */

    SigDisableInterrupts();

    /* First, translate the area back up through the hierarchy to
     * cells that are roots of windows.
     */

    for (use = cellDef->cd_parents; use != NULL; use = use->cu_nextuse)
    {
	/* We're only interested in a use if it's expanded in one of
	 * the windows of expandMask.  Our new expand mask is the
	 * AND of the old one and the windows in which this use is
	 * expanded.
	 */

	newMask = expandMask & use->cu_expandMask;
	if (newMask == 0) continue;

	/* If this use has no parents, it might be the root of a window.
	 * If so, log the area in the window.
	 */

	if (use->cu_parent == NULL)
	{
	    dbwLayersChanged = layers;
	    (void) WindSearch((ClientData) DBWclientID, (ClientData) use,
		defArea, dbwChangedFunc, (ClientData) defArea);
	    continue;
	}

	/* This use isn't a root use.  If it isn't an array use, just
	 * translate the area back into the coordinates of the parent
	 * and invoke ourselves recursively.
	 */

	if ((use->cu_xlo == use->cu_xhi) && (use->cu_ylo == use->cu_yhi))
	{
	    GeoTransRect(&use->cu_transform, defArea, &newArea);
	    DBWAreaChanged(use->cu_parent, &newArea, newMask, layers);
	    continue;
	}

	/* This is an array.  If the area to be redisplayed is a
	 * substantial fraction of the total area of the array,
	 * just redisplay the whole array.  Otherwise redisplay
	 * the individual elements.
	 */

	if ((2*(defArea->r_xtop - defArea->r_xbot) >
	    (cellDef->cd_bbox.r_xtop - cellDef->cd_bbox.r_xbot))
	    || (2*(defArea->r_ytop - defArea->r_ybot) >
	    (cellDef->cd_bbox.r_ytop - cellDef->cd_bbox.r_ybot)))
	{
	    DBComputeArrayArea(defArea, use, use->cu_xlo,
		use->cu_ylo, &newArea);
	    DBComputeArrayArea(defArea, use, use->cu_xhi,
		use->cu_yhi, &tmp);
	    (void) GeoInclude(&newArea, &tmp);
	    GeoTransRect(&use->cu_transform, &tmp, &newArea);
	    DBWAreaChanged(use->cu_parent, &newArea, newMask, layers);
	}
	else
	{
	    if (use->cu_xlo > use->cu_xhi)
	    {
		xlo = use->cu_xhi; xhi = use->cu_xlo;
	    }
	    else
	    {
		xlo = use->cu_xlo; xhi = use->cu_xhi;
	    }
	    if (use->cu_ylo > use->cu_yhi)
	    {
		ylo = use->cu_yhi; yhi = use->cu_ylo;
	    }
	    else
	    {
		ylo = use->cu_ylo; yhi = use->cu_yhi;
	    }
	    for (y = ylo ; y <= yhi; y++)
		for (x = xlo; x <= xhi; x++)
		{
		    DBComputeArrayArea(defArea, use, x, y, &tmp);
		    GeoTransRect(&use->cu_transform, &tmp, &newArea);
		    DBWAreaChanged(use->cu_parent, &newArea, newMask, layers);
		}
	}
    }
    SigEnableInterrupts();
}


/*
 * ----------------------------------------------------------------------------
 *
 * dbwChangedFunc --
 *
 * 	This function is invoked by WindSearch under control of
 *	DBWAreaChanged.  It notifies the window manager to redisplay
 *	an area of a window.
 *
 * Results:
 *	Always returns 0 to keep the search alive.
 *
 * Side effects:
 *	An area to be redisplayed is recorded.
 *
 * ----------------------------------------------------------------------------
 */

int
dbwChangedFunc(
    MagWindow *w,			/* Window in which to record area. */
    Rect *area)			/* (Client data) Area to be redisplayed, in
				 * coordinates of the root definition.
				 */
{
    Rect screenArea;
    TileTypeBitMask tmp;
    DBWclientRec *crec = (DBWclientRec *) w->w_clientData;

    /* If none of the layers being redisplayed is visible in this
     * window, then there's no need to do anything.
     */

    if (dbwLayersChanged != NULL)
    {
	TTMaskAndMask3(&tmp, dbwLayersChanged, &crec->dbw_visibleLayers);
	if (TTMaskIsZero(&tmp)) return 0;
    }

    /* Compute screen area to redisplay, in pixels. */

    WindSurfaceToScreen(w, area, &screenArea);
    GeoClip(&screenArea, &w->w_screenArea);

    /* If labels are being redisplayed, expand the redisplay area
     * to account for labels that are rooted in the given area but
     * stick out past it.
     */

    if (dbwLayersChanged == NULL)
    {
	screenArea.r_xbot += crec->dbw_expandAmounts.r_xbot;
	screenArea.r_ybot += crec->dbw_expandAmounts.r_ybot;
	screenArea.r_xtop += crec->dbw_expandAmounts.r_xtop;
	screenArea.r_ytop += crec->dbw_expandAmounts.r_ytop;
    }
    else if (GrPixelCorrect == 0)
    {
	/* Correct for OpenGL coordinate system */
	screenArea.r_xbot--;
	screenArea.r_ybot--;
	screenArea.r_xtop++;
	screenArea.r_ytop++;
    }

    /* If watching is enabled for this window, so sorry but the whole
     * thing will have to be redisplayed (even a small change could have
     * affected many many tiles.
     */

    if (crec->dbw_watchPlane >= 0) WindAreaChanged(w, (Rect *) NULL);
    else WindAreaChanged(w, &screenArea);
    return 0;
}

/*
 * ----------------------------------------------------------------------------
 *
 * DBWLabelChanged --
 *
 * 	This procedure is invoked when a label has been created or
 *	deleted.  It figures out which areas to redisplay in order
 *	to make sure that the label is completely redrawn.
 *
 * Results:
 *	None.
 *
 * Side effects:
 *	The list of areas to be redisplayed is modified.
 *
 * ----------------------------------------------------------------------------
 */


/* The following stuff is shared by the procedures below. */

extern int dbwLabelChangedFunc();  /* Function to call for each label. */

void
DBWLabelChanged(
    CellDef *cellDef,		/* Cell definition containing label. */
    Label *lab,			/* The label structure */
    int mask)			/* Mask of windows where changes should be
				 * reflected (DBW_ALLWINDOWS selects all
				 * windows, and is usually the right value.)
				 */
{
    CellUse *use;
    Rect saveArea, tmp;
    int newMask, savePos;
    int x, y, xlo, ylo, xhi, yhi;

    /* This procedure is basically the same as DBWAreaChanged, so
     * see that procedure for documentation on how this all works.
     */

    saveArea = lab->lab_rect;
    savePos = lab->lab_just;

    SigDisableInterrupts();
    for (use = cellDef->cd_parents; use != NULL; use = use->cu_nextuse)
    {
	newMask = mask & use->cu_expandMask;
	if (newMask == 0) continue;

	if (use->cu_parent == NULL)
	{
	    /* Got the root use for a window.  Find the relevant windows
	     * and do the rest of the processing on a per-window basis.
	     */

	    (void) WindSearch((ClientData) DBWclientID, (ClientData) use,
		(Rect *) NULL, dbwLabelChangedFunc, (ClientData) lab);
	    continue;
	}

	if (use->cu_xlo > use->cu_xhi)
	{
	    xlo = use->cu_xhi;
	    xhi = use->cu_xlo;
	}
	else
	{
	    xlo = use->cu_xlo;
	    xhi = use->cu_xhi;
	}
	if (use->cu_ylo > use->cu_yhi)
	{
	    ylo = use->cu_yhi;
	    yhi = use->cu_ylo;
	}
	else
	{
	    ylo = use->cu_ylo;
	    yhi = use->cu_yhi;
	}
	for (y = ylo; y <= yhi; y++)
	    for (x = xlo; x <= xhi; x++)
	    {
		DBComputeArrayArea(&lab->lab_rect, use, x, y, &tmp);
		GeoTransRect(&use->cu_transform, &tmp, &lab->lab_rect);
		lab->lab_just = GeoTransPos(&use->cu_transform, lab->lab_just);
		DBWLabelChanged(use->cu_parent, lab, newMask);
	    }
    }
    lab->lab_rect = saveArea;
    lab->lab_just = savePos;

    SigEnableInterrupts();
}

int
dbwLabelChangedFunc(
    MagWindow *w,		/* Window in which label is displayed. */
    Label *lab)			/* Label being changed.	*/
{
    Rect screenArea, textArea;
    int size;

    if (lab->lab_font < 0)
    {
	WindSurfaceToScreen(w, &lab->lab_rect, &screenArea);
	size = ((DBWclientRec *) w->w_clientData)->dbw_labelSize;
	if (size < GR_TEXT_SMALL)
	    textArea = GrCrossRect;
	else
	{
	    GrLabelSize(lab->lab_text, lab->lab_just, size, &textArea);
	    (void) GeoInclude(&GrCrossRect, &textArea);
	}
	screenArea.r_xbot += textArea.r_xbot;
	screenArea.r_ybot += textArea.r_ybot;
	screenArea.r_xtop += textArea.r_xtop;
	screenArea.r_ytop += textArea.r_ytop;
    }
    else
    {
	WindSurfaceToScreen(w, &lab->lab_bbox, &screenArea);
    }
    WindAreaChanged(w, &screenArea);
    return 0;
}

/*
 * Technology initialization for the display module.
 */

global TileTypeBitMask	*DBWStyleToTypesTbl = NULL;

/*
 * ----------------------------------------------------------------------------
 * DBWTechInitStyles --
 *
 * Initialize the display module's technology dependent variables.
 *
 * Results:
 *	None.
 *
 * Side effects:
 *	Clears the display module's technology dependent information.
 * ----------------------------------------------------------------------------
 */

void
DBWTechInitStyles()
{
    int i;

    if (DBWNumStyles == 0)
    {
	TxError("Error:  Attempting to define tech styles before reading "
		"dstyle file!\n");
	return;
    }
    if (DBWStyleToTypesTbl != NULL)
	freeMagic(DBWStyleToTypesTbl);

    DBWStyleToTypesTbl = (TileTypeBitMask *)mallocMagic(DBWNumStyles *
		sizeof(TileTypeBitMask));

    for (i = 0; i < DBWNumStyles; i++)
	TTMaskZero(DBWStyleToTypesTbl + i);
}


/*
 * ----------------------------------------------------------------------------
 *
 * DBWTechParseStyle --
 *
 *	Turn a style entry (either a style number or name) into an index
 *	into the styles array.
 *
 * Results:  Index into the DBW styles table, or -1 if no style found.
 *
 * Side Effects:  None.
 *
 * ----------------------------------------------------------------------------
 */

int
DBWTechParseStyle(
    char *stylestr)
{
    int sidx, style;

    if (StrIsInt(stylestr))
    {
	style = atoi(stylestr);
	for (sidx = 0; sidx < DBWNumStyles; sidx++)
	    if (GrStyleTable[sidx + TECHBEGINSTYLES].idx == style)
		break;
    }
    else {
	for (sidx = 0; sidx < DBWNumStyles; sidx++)
	    if (!strcmp(GrStyleTable[sidx + TECHBEGINSTYLES].longname,
			stylestr))
		break;
    }
    if (sidx >= DBWNumStyles)
	return -1;
    else
	return sidx;
}

/*
 * ----------------------------------------------------------------------------
 * DBWTechAddStyle --
 *
 * Add a new entry to the style tables.
 *
 * Results:
 *	TRUE if successful, FALSE on error.
 *
 * Side effects:
 *	Updates the display module's technology variables.
 * ----------------------------------------------------------------------------
 */

bool
DBWTechAddStyle(
    char *sectionName,
    int argc,
    char *argv[])
{
    TileType t, r;
    TileTypeBitMask *rMask;
    int i, sidx;
    static char styleType[50];
    char *pathptr;

    if (argc < 2)
    {
	TechError("Badly formed line in \"style\" section\n");
    }
    else if (strcmp(argv[0], "styletype") == 0)
    {
	(void) strncpy(styleType, argv[1], 49);
	styleType[49] = 0;
	DBWStyleType = styleType;

	/* Optional 3rd and higher arguments are pathnames */

	for (i = 2; i <= argc; i++)
	{
	    if (i == argc)
		pathptr = SysLibPath;
	    else
		pathptr = argv[i];

	    /* Learning the style type precipitates immediate reading	*/
	    /* of the color map and style files.			*/

	    if (GrReadCMap(DBWStyleType, (char *)NULL, MainMonType, ".", pathptr))
		break;
	}
	if (i > argc) return FALSE;

	if (GrLoadStyles(DBWStyleType, ".", pathptr) != 0)
	    return FALSE;

	DBWTechInitStyles();

	if (!GrLoadCursors(".", pathptr))
	    return FALSE;

	GrSetCursor(0);
    }
    else
    {
	if ((t = DBTechNoisyNameType(argv[0])) < 0) return (FALSE);

	/* Allow space-separated list of styles for each type */

	for (i = 1; i < argc; i++)
	{
	    sidx = DBWTechParseStyle(argv[i]);
	    if (sidx < 0)
		TechError("Invalid style \"%s\" for tile type %s\n", argv[i], argv[0]);
	    else
	    {
		TTMaskSetType(&DBWStyleToTypesTbl[sidx], t);

		/* If type t is a contact, then any stacked contact type which	*/
		/* has t as a residue, and for which the home plane of the	*/
		/* stacked contact is also the home plane of t, should be added	*/
		/* to the list of types to be painted with this style.		*/

		if (DBIsContact(t) && (t < DBNumUserLayers))
		    for (r = DBNumUserLayers; r < DBNumTypes; r++)
		    {
			rMask = DBResidueMask(r);
			if (TTMaskHasType(rMask, t) && (DBPlane(r) == DBPlane(t)))
			    TTMaskSetType(&DBWStyleToTypesTbl[sidx], r);
		    }
	    }
	}
    }
    return TRUE;
}
