stk/Tk/unix/tkUnixDraw.c

172 lines
4.8 KiB
C
Raw Blame History

This file contains invisible Unicode characters

This file contains invisible Unicode characters that are indistinguishable to humans but may be processed differently by a computer. If you think that this is intentional, you can safely ignore this warning. Use the Escape button to reveal them.

/*
* tkUnixDraw.c --
*
* This file contains X specific drawing routines.
*
* Copyright (c) 1995 Sun Microsystems, Inc.
*
* See the file "license.terms" for information on usage and redistribution
* of this file, and for a DISCLAIMER OF ALL WARRANTIES.
*
* SCCS: @(#) tkUnixDraw.c 1.9 97/03/21 11:16:18
*/
#include "tkPort.h"
#include "tkInt.h"
/*
* The following structure is used to pass information to
* ScrollRestrictProc from TkScrollWindow.
*/
typedef struct ScrollInfo {
int done; /* Flag is 0 until filtering is done. */
Display *display; /* Display to filter. */
Window window; /* Window to filter. */
TkRegion region; /* Region into which damage is accumulated. */
int dx, dy; /* Amount by which window was shifted. */
} ScrollInfo;
/*
* Forward declarations for procedures declared later in this file:
*/
static Tk_RestrictAction ScrollRestrictProc _ANSI_ARGS_((
ClientData arg, XEvent *eventPtr));
/*
*----------------------------------------------------------------------
*
* TkScrollWindow --
*
* Scroll a rectangle of the specified window and accumulate
* damage information in the specified Region.
*
* Results:
* Returns 0 if no damage additional damage was generated. Sets
* damageRgn to contain the damaged areas and returns 1 if
* GraphicsExpose events were detected.
*
* Side effects:
* Scrolls the bits in the window and enters the event loop
* looking for damage events.
*
*----------------------------------------------------------------------
*/
int
TkScrollWindow(tkwin, gc, x, y, width, height, dx, dy, damageRgn)
Tk_Window tkwin; /* The window to be scrolled. */
GC gc; /* GC for window to be scrolled. */
int x, y, width, height; /* Position rectangle to be scrolled. */
int dx, dy; /* Distance rectangle should be moved. */
TkRegion damageRgn; /* Region to accumulate damage in. */
{
Tk_RestrictProc *oldProc;
ClientData oldArg, dummy;
ScrollInfo info;
XCopyArea(Tk_Display(tkwin), Tk_WindowId(tkwin), Tk_WindowId(tkwin), gc,
x, y, (unsigned int) width, (unsigned int) height, x + dx, y + dy);
info.done = 0;
info.window = Tk_WindowId(tkwin);
info.display = Tk_Display(tkwin);
info.region = damageRgn;
info.dx = dx;
info.dy = dy;
/*
* Sync the event stream so all of the expose events will be on the
* Tk event queue before we start filtering. This avoids busy waiting
* while we filter events.
*/
TkpSync(info.display);
oldProc = Tk_RestrictEvents(ScrollRestrictProc, (ClientData) &info,
&oldArg);
while (!info.done) {
Tcl_ServiceEvent(TCL_WINDOW_EVENTS);
}
Tk_RestrictEvents(oldProc, oldArg, &dummy);
return XEmptyRegion((Region) damageRgn) ? 0 : 1;
}
/*
*----------------------------------------------------------------------
*
* ScrollRestrictProc --
*
* A Tk_RestrictProc used by TkScrollWindow to gather up Expose
* information into a single damage region. It accumulates damage
* events on the specified window until a NoExpose or the last
* GraphicsExpose event is detected.
*
* Results:
* None.
*
* Side effects:
* Discards Expose events after accumulating damage information
* for a particular window.
*
*----------------------------------------------------------------------
*/
static Tk_RestrictAction
ScrollRestrictProc(arg, eventPtr)
ClientData arg;
XEvent *eventPtr;
{
ScrollInfo *info = (ScrollInfo *) arg;
XRectangle rect;
/*
* Defer events which aren't for the specified window.
*/
if (info->done || (eventPtr->xany.display != info->display)
|| (eventPtr->xany.window != info->window)) {
return TK_DEFER_EVENT;
}
if (eventPtr->type == NoExpose) {
info->done = 1;
} else if (eventPtr->type == GraphicsExpose) {
rect.x = eventPtr->xgraphicsexpose.x;
rect.y = eventPtr->xgraphicsexpose.y;
rect.width = eventPtr->xgraphicsexpose.width;
rect.height = eventPtr->xgraphicsexpose.height;
XUnionRectWithRegion(&rect, (Region) info->region,
(Region) info->region);
if (eventPtr->xgraphicsexpose.count == 0) {
info->done = 1;
}
} else if (eventPtr->type == Expose) {
/*
* This case is tricky. This event was already queued before
* the XCopyArea was issued. If this area overlaps the area
* being copied, then some of the copied area may be invalid.
* The easiest way to handle this case is to mark both the
* original area and the shifted area as damaged.
*/
rect.x = eventPtr->xexpose.x;
rect.y = eventPtr->xexpose.y;
rect.width = eventPtr->xexpose.width;
rect.height = eventPtr->xexpose.height;
XUnionRectWithRegion(&rect, (Region) info->region,
(Region) info->region);
rect.x += info->dx;
rect.y += info->dy;
XUnionRectWithRegion(&rect, (Region) info->region,
(Region) info->region);
} else {
return TK_DEFER_EVENT;
}
return TK_DISCARD_EVENT;
}