2 * Scroll windows and DCs
4 * Copyright 1993 David W. Metcalfe
5 * Copyright 1995, 1996 Alex Korobka
6 * Copyright 2001 Alexandre Julliard
8 * This library is free software; you can redistribute it and/or
9 * modify it under the terms of the GNU Lesser General Public
10 * License as published by the Free Software Foundation; either
11 * version 2.1 of the License, or (at your option) any later version.
13 * This library is distributed in the hope that it will be useful,
14 * but WITHOUT ANY WARRANTY; without even the implied warranty of
15 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
16 * Lesser General Public License for more details.
18 * You should have received a copy of the GNU Lesser General Public
19 * License along with this library; if not, write to the Free Software
20 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
34 #include "wine/debug.h"
36 WINE_DEFAULT_DEBUG_CHANNEL(scroll);
38 static void dump_region( char *p, HRGN hrgn)
45 TRACE( "%s null region\n", p );
48 if (!(size = GetRegionData( hrgn, 0, NULL ))) {
51 if (!(data = HeapAlloc( GetProcessHeap(), 0, size ))) return;
52 GetRegionData( hrgn, size, data );
53 TRACE("%s %ld rects:", p, data->rdh.nCount );
54 for (i = 0, rect = (RECT *)data->Buffer; i<20 && i < data->rdh.nCount; i++, rect++)
55 TRACE( " %s", wine_dbgstr_rect( rect));
57 HeapFree( GetProcessHeap(), 0, data );
60 /*************************************************************************
63 BOOL X11DRV_ScrollDC( HDC hdc, INT dx, INT dy, const RECT *lprcScroll,
64 const RECT *lprcClip, HRGN hrgnUpdate, LPRECT lprcUpdate )
66 RECT rcSrc, rcClip, offset;
67 INT dxdev, dydev, res;
68 HRGN DstRgn, clipRgn, visrgn;
69 INT code = X11DRV_START_EXPOSURES;
71 TRACE("dx,dy %d,%d lprcScroll %p lprcClip %p hrgnUpdate %p lprcUpdate %p\n",
72 dx, dy, lprcScroll, lprcClip, hrgnUpdate, lprcUpdate);
73 /* enable X-exposure events */
74 if (hrgnUpdate || lprcUpdate)
75 ExtEscape( hdc, X11DRV_ESCAPE, sizeof(code), (LPSTR)&code, 0, NULL );
76 /* get the visible region */
77 visrgn=CreateRectRgn( 0, 0, 0, 0);
78 GetRandomRgn( hdc, visrgn, SYSRGN);
79 if( !(GetVersion() & 0x80000000)) {
82 GetDCOrgEx(hdc, &org);
83 OffsetRgn( visrgn, -org.x, -org.y);
85 /* intersect with the clipping Region if the DC has one */
86 clipRgn = CreateRectRgn( 0, 0, 0, 0);
87 if (GetClipRgn( hdc, clipRgn) != 1) {
88 DeleteObject(clipRgn);
91 CombineRgn( visrgn, visrgn, clipRgn, RGN_AND);
92 /* only those pixels in the scroll rectangle that remain in the clipping
93 * rect are scrolled. So first combine Scroll and Clipping rectangles,
97 IntersectRect( &rcClip, lprcClip, lprcScroll);
104 GetClipBox( hdc, &rcClip);
105 /* Then clip again to get the source rectangle that will remain in the
108 OffsetRect( &rcSrc, -dx, -dy);
109 IntersectRect( &rcSrc, &rcSrc, &rcClip);
110 /* now convert to device coordinates */
111 LPtoDP(hdc, (LPPOINT)&rcSrc, 2);
113 SetRect(&offset, 0, 0, dx, dy);
114 LPtoDP(hdc, (LPPOINT)&offset, 2);
115 dxdev = offset.right - offset.left;
116 dydev= offset.bottom - offset.top;
117 /* now intersect with the visible region to get the pixels that will
119 DstRgn = CreateRectRgnIndirect( &rcSrc);
120 res = CombineRgn( DstRgn, DstRgn, visrgn, RGN_AND);
121 /* and translate, giving the destination region */
122 OffsetRgn( DstRgn, dxdev, dydev);
123 if( TRACE_ON( scroll)) dump_region( "Destination scroll region: ", DstRgn);
124 /* if there are any, do it */
125 if( res > NULLREGION) {
127 /* clip to the destination region, so we can BitBlt with a simple
128 * bounding rectangle */
130 ExtSelectClipRgn( hdc, DstRgn, RGN_AND);
132 SelectClipRgn( hdc, DstRgn);
133 GetRgnBox( DstRgn, &rect);
134 DPtoLP(hdc, (LPPOINT)&rect, 2);
135 BitBlt( hdc, rect.left, rect.top,
136 rect.right - rect.left, rect.bottom -rect.top,
137 hdc, rect.left - dx, rect.top - dy, SRCCOPY);
139 /* compute the update areas. This is the combined clip rectangle
140 * minus the scrolled region, and intersected with the visible
142 if (hrgnUpdate || lprcUpdate)
144 HRGN hrgn = hrgnUpdate;
147 /* collect all the exposures */
148 code = X11DRV_END_EXPOSURES;
149 ExtEscape( hdc, X11DRV_ESCAPE, sizeof(code), (LPSTR)&code,
150 sizeof(ExpRgn), (LPSTR)&ExpRgn );
151 /* Covert the combined clip rectangle to device coordinates */
152 LPtoDP(hdc, (LPPOINT)&rcClip, 2);
154 SetRectRgn( hrgn, rcClip.left, rcClip.top, rcClip.right,
157 hrgn = CreateRectRgnIndirect( &rcClip);
158 CombineRgn( hrgn, hrgn, visrgn, RGN_AND);
159 CombineRgn( hrgn, hrgn, DstRgn, RGN_DIFF);
160 /* add the exposures to this */
162 if( TRACE_ON( scroll)) dump_region( "Expose region: ", ExpRgn);
163 CombineRgn( hrgn, hrgn, ExpRgn, RGN_OR);
164 DeleteObject( ExpRgn);
166 if( TRACE_ON( scroll)) dump_region( "Update region: ", hrgn);
168 GetRgnBox( hrgn, lprcUpdate );
169 /* Put the lprcUpdate in logical coordinates */
170 DPtoLP( hdc, (LPPOINT)lprcUpdate, 2 );
171 TRACE("returning lprcUpdate %s\n", wine_dbgstr_rect(lprcUpdate));
176 SelectClipRgn( hdc, clipRgn);
177 DeleteObject( visrgn);
178 DeleteObject( DstRgn);
179 if( clipRgn) DeleteObject( clipRgn);