1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
|
//
// "$Id: fl_scroll_area.cxx,v 1.3 1998/10/21 14:20:57 mike Exp $"
//
// Scrolling routines for the Fast Light Tool Kit (FLTK).
//
// Copyright 1998 by Bill Spitzak and others.
//
// This library is free software; you can redistribute it and/or
// modify it under the terms of the GNU Library General Public
// License as published by the Free Software Foundation; either
// version 2 of the License, or (at your option) any later version.
//
// This library is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
// Library General Public License for more details.
//
// You should have received a copy of the GNU Library General Public
// License along with this library; if not, write to the Free Software
// Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307
// USA.
//
// Please report all bugs and problems to "fltk-bugs@easysw.com".
//
// Drawing function to move the contents of a rectangle. This is passed
// a "callback" which is called to draw rectangular areas that are moved
// into the drawing area.
#include <FL/x.H>
// scroll a rectangle and redraw the newly exposed portions:
void fl_scroll(int X, int Y, int W, int H, int dx, int dy,
void (*draw_area)(void*, int,int,int,int), void* data)
{
if (!dx && !dy) return;
if (dx <= -W || dx >= W || dy <= -H || dy >= H) {
// no intersection of old an new scroll
draw_area(data,X,Y,W,H);
return;
}
int src_x, src_w, dest_x, clip_x, clip_w;
if (dx > 0) {
src_x = X;
dest_x = X+dx;
src_w = W-dx;
clip_x = X;
clip_w = dx;
} else {
src_x = X-dx;
dest_x = X;
src_w = W+dx;
clip_x = X+src_w;
clip_w = W-src_w;
}
int src_y, src_h, dest_y, clip_y, clip_h;
if (dy > 0) {
src_y = Y;
dest_y = Y+dy;
src_h = H-dy;
clip_y = Y;
clip_h = dy;
} else {
src_y = Y-dy;
dest_y = Y;
src_h = H+dy;
clip_y = Y+src_h;
clip_h = H-src_h;
}
#ifdef WIN32
BitBlt(fl_gc, dest_x, dest_y, src_w, src_h, fl_gc, src_x, src_y,SRCCOPY);
// NYI: need to redraw areas that the source of BitBlt was bad due to
// overlapped windows, probably similar to X version:
#else
XCopyArea(fl_display, fl_window, fl_window, fl_gc,
src_x, src_y, src_w, src_h, dest_x, dest_y);
// we have to sync the display and get the GraphicsExpose events! (sigh)
for (;;) {
XEvent e; XWindowEvent(fl_display, fl_window, ExposureMask, &e);
if (e.type == NoExpose) break;
// otherwise assumme it is a GraphicsExpose event:
draw_area(data, e.xexpose.x, e.xexpose.y,
e.xexpose.width, e.xexpose.height);
if (!e.xgraphicsexpose.count) break;
}
#endif
if (dx) draw_area(data, clip_x, dest_y, clip_w, src_h);
if (dy) draw_area(data, X, clip_y, W, clip_h);
}
//
// End of "$Id: fl_scroll_area.cxx,v 1.3 1998/10/21 14:20:57 mike Exp $".
//
|
