Porthole.c   [plain text]

/*
 * $Xorg: Porthole.c,v 1.4 2001/02/09 02:03:45 xorgcvs Exp $
 *
Copyright 1990, 1994, 1998  The Open Group

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The above copyright notice and this permission notice shall be included in
all copies or substantial portions of the Software.

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in this Software without prior written authorization from The Open Group.
 *
 * Author:  Jim Fulton, MIT X Consortium
 * 
 * This widget is a trivial clipping widget.  It is typically used with a
 * panner or scrollbar to navigate.
 */
/* $XFree86: xc/lib/Xaw/Porthole.c,v 1.6 2001/01/17 19:42:29 dawes Exp $ */

#ifdef HAVE_CONFIG_H
#include <config.h>
#endif
#include <X11/IntrinsicP.h>
#include <X11/StringDefs.h>
#include <X11/Xmu/Misc.h>
#include <X11/Xaw/PortholeP.h>
#include <X11/Xaw/XawInit.h>
#include "Private.h"

/*
 * Class Methods
 */
static void XawPortholeChangeManaged(Widget);
static XtGeometryResult XawPortholeGeometryManager(Widget, XtWidgetGeometry*,
						   XtWidgetGeometry*);
static XtGeometryResult XawPortholeQueryGeometry(Widget, XtWidgetGeometry*,
						 XtWidgetGeometry*);
static void XawPortholeRealize(Widget, Mask*, XSetWindowAttributes*);
static void XawPortholeResize(Widget);

/*
 * Prototypes
 */
static Widget find_child(PortholeWidget);
static void layout_child(PortholeWidget, Widget, XtWidgetGeometry*,
			 Position*, Position*, Dimension*, Dimension*);
static void SendReport(PortholeWidget, unsigned int);

/*
 * Initialization
 */
#define offset(field)	XtOffsetOf(PortholeRec, porthole.field)
static XtResource resources[] = {
  {
    XtNreportCallback,
    XtCReportCallback,
    XtRCallback,
    sizeof(XtPointer),
    offset(report_callbacks),
    XtRCallback,
    NULL
  },
};
#undef offset

#define Superclass	(&compositeClassRec)
PortholeClassRec portholeClassRec = {
  /* core */
  {
    (WidgetClass)Superclass,		/* superclass */
    "Porthole",				/* class_name */
    sizeof(PortholeRec),		/* widget_size */
    XawInitializeWidgetSet,		/* class_initialize */
    NULL,				/* class_part_initialize */
    False,				/* class_inited */
    NULL,				/* initialize */
    NULL,				/* initialize_hook */
    XawPortholeRealize,			/* realize */
    NULL,				/* actions */
    0,					/* num_actions */
    resources,				/* resources */
    XtNumber(resources),		/* num_resources */
    NULLQUARK,				/* xrm_class */
    True,				/* compress_motion */
    True,				/* compress_exposure */
    True,				/* compress_enterleave */
    False,				/* visible_interest */
    NULL,				/* destroy */
    XawPortholeResize,			/* resize */
    NULL,				/* expose */
    NULL,				/* set_values */
    NULL,				/* set_values_hook */
    XtInheritSetValuesAlmost,		/* set_values_almost */
    NULL,				/* get_values_hook */
    NULL,				/* accept_focus */
    XtVersion,				/* version */
    NULL,				/* callback_private */
    NULL,				/* tm_table */
    XawPortholeQueryGeometry,		/* query_geometry */
    XtInheritDisplayAccelerator,	/* display_accelerator */
    NULL,				/* extension */
  },
  /* composite */
  { 
    XawPortholeGeometryManager,		/* geometry_manager */
    XawPortholeChangeManaged,		/* change_managed */
    XtInheritInsertChild,		/* insert_child */
    XtInheritDeleteChild,		/* delete_child */
    NULL,				/* extension */
  },
  { /* porthole */
    NULL,				/* extension */
  },
};

WidgetClass portholeWidgetClass = (WidgetClass)&portholeClassRec;

/*
 * Implementation
 */
static Widget
find_child(PortholeWidget pw)
{
    Widget *children;
    unsigned int i;

    /*
     * Find the managed child on which we should operate.  Ignore multiple
     * managed children
     */
    for (i = 0, children = pw->composite.children;
	 i < pw->composite.num_children; i++, children++)
	if (XtIsManaged(*children))
	    return (*children);

    return (NULL);
}

static void
SendReport(PortholeWidget pw, unsigned int changed)
{
    Widget child = find_child(pw);

    if (pw->porthole.report_callbacks && child) {
	XawPannerReport prep;

	prep.changed = changed;
	prep.slider_x = -XtX(child);	/* porthole is "inner" */
	prep.slider_y = -XtY(child);	/* child is outer since it is larger */
	prep.slider_width = XtWidth(pw);
	prep.slider_height = XtHeight(pw);
	prep.canvas_width = XtWidth(child);
	prep.canvas_height = XtHeight(child);
	XtCallCallbackList((Widget)pw, pw->porthole.report_callbacks,
			   (XtPointer)&prep);
    }
}

static void
layout_child(PortholeWidget pw, Widget child, XtWidgetGeometry *geomp,
	     Position *xp, Position *yp, Dimension *widthp, Dimension *heightp)
{
    Position minx, miny;

    *xp = XtX(child);			/* default to current values */
    *yp = XtY(child);
    *widthp = XtWidth(child);
    *heightp = XtHeight(child);
    if (geomp) {			/* mix in any requested changes */
	if (geomp->request_mode & CWX)
	    *xp = geomp->x;
	if (geomp->request_mode & CWY)
	    *yp = geomp->y;
	if (geomp->request_mode & CWWidth)
	    *widthp = geomp->width;
	if (geomp->request_mode & CWHeight)
	    *heightp = geomp->height;
    }

    /*
     * Make sure that the child is at least as large as the porthole; there
     * is no maximum size
     */
    if (*widthp < XtWidth(pw)) *widthp = XtWidth(pw);
    if (*heightp < XtHeight(pw)) *heightp = XtHeight(pw);

    /*
     * Make sure that the child is still on the screen.  Note that this must
     * be done *after* the size computation so that we know where to put it
     */
    minx = (Position)XtWidth(pw) - (Position)*widthp;
    miny = (Position)XtHeight(pw) - (Position)*heightp;

    if (*xp < minx)
	*xp = minx;
    if (*yp < miny)
	*yp = miny;

    if (*xp > 0)
	*xp = 0;
    if (*yp > 0)
	*yp = 0;
}

static void
XawPortholeRealize(Widget gw, Mask *valueMask, XSetWindowAttributes *attr)
{
    attr->bit_gravity = NorthWestGravity;
    *valueMask |= CWBitGravity;

    if (XtWidth(gw) < 1)
	XtWidth(gw) = 1;
    if (XtHeight(gw) < 1)
	XtHeight(gw) = 1;
    (*portholeWidgetClass->core_class.superclass->core_class.realize)
	(gw, valueMask, attr);
}

static void
XawPortholeResize(Widget gw)
{
    PortholeWidget pw = (PortholeWidget)gw;
    Widget child = find_child(pw);

    /*
     * If we have a child, we need to make sure that it is at least as big
     * as we are and in the right place
     */
    if (child) {
	Position x, y;
	Dimension width, height;

	layout_child(pw, child, NULL, &x, &y, &width, &height);
	XtConfigureWidget(child, x, y, width, height, 0);
    }

    SendReport(pw, XawPRCanvasWidth | XawPRCanvasHeight);
}

static XtGeometryResult
XawPortholeQueryGeometry(Widget gw, XtWidgetGeometry *intended,
			 XtWidgetGeometry *preferred)
{
    PortholeWidget pw = (PortholeWidget)gw;
    Widget child = find_child(pw);

    if (child) {
#define SIZEONLY (CWWidth | CWHeight)
	preferred->request_mode = SIZEONLY;
	preferred->width = XtWidth(child);
	preferred->height = XtHeight(child);

	if ((intended->request_mode & SIZEONLY) == SIZEONLY &&
	    intended->width == preferred->width &&
	    intended->height == preferred->height)
	    return (XtGeometryYes);
	else if (preferred->width == XtWidth(pw) &&
		 preferred->height == XtHeight(pw))
	    return (XtGeometryNo);

	return (XtGeometryAlmost);
#undef SIZEONLY
    }

    return (XtGeometryNo);
}

static XtGeometryResult
XawPortholeGeometryManager(Widget w, XtWidgetGeometry *req,
			   XtWidgetGeometry *reply)
{
    PortholeWidget pw = (PortholeWidget) w->core.parent;
    Widget child = find_child(pw);
    Bool okay = True;

    if (child != w)
	return (XtGeometryNo);

    *reply = *req;			/* assume we'll grant everything */

    if ((req->request_mode & CWBorderWidth) && req->border_width != 0) {
	reply->border_width = 0;
	okay = False;
    }

    layout_child(pw, child, req, &reply->x, &reply->y,
		 &reply->width, &reply->height);

    if ((req->request_mode & CWX) && req->x != reply->x)
	okay = False;
    if ((req->request_mode & CWY) && req->x != reply->x)
	okay = False;
    if ((req->request_mode & CWWidth) && req->width != reply->width)
	okay = False;
    if ((req->request_mode & CWHeight) && req->height != reply->height)
	okay = False;

    /*
     * If we failed on anything, simply return without touching widget
     */
    if (!okay)
	return (XtGeometryAlmost);

    /*
     * If not just doing a query, update widget and send report.  Note that
     * we will often set fields that weren't requested because we want to keep
     * the child visible
     */
    if (!(req->request_mode & XtCWQueryOnly)) {
	unsigned int changed = 0;

	if (XtX(child) != reply->x) {
	    changed |= XawPRSliderX;
	    XtX(child) = reply->x;
	}
	if (XtY(child) != reply->y) {
	    changed |= XawPRSliderY;
	    XtY(child) = reply->y;
	}
	if (XtWidth(child) != reply->width) {
	    changed |= XawPRSliderWidth;
	    XtWidth(child) = reply->width;
	}
	if (XtHeight(child) != reply->height) {
	    changed |= XawPRSliderHeight;
	    XtHeight(child) = reply->height;
	}
	if (changed)
	    SendReport(pw, changed);
    }

    return (XtGeometryYes);		/* success! */
}

static void
XawPortholeChangeManaged(Widget gw)
{
    PortholeWidget pw = (PortholeWidget)gw;
    Widget child = find_child (pw);	/* ignore extra children */

    if (child) {
	if (!XtIsRealized (gw)) {
	    XtWidgetGeometry geom, retgeom;

	    geom.request_mode = 0;
	    if (XtWidth(pw) == 0) {
		geom.width = XtWidth(child);
		geom.request_mode |= CWWidth;
	    }
	    if (XtHeight(pw) == 0) {
		geom.height = XtHeight(child);
		geom.request_mode |= CWHeight;
	    }
	    if (geom.request_mode &&
		XtMakeGeometryRequest (gw, &geom, &retgeom)
		== XtGeometryAlmost)
		(void)XtMakeGeometryRequest(gw, &retgeom, NULL);
	}
	
	XtResizeWidget(child, Max(XtWidth(child), XtWidth(pw)),
		       Max(XtHeight(child), XtHeight(pw)), 0);

	SendReport(pw, XawPRAll);
    }
}