1 //
2 // "$Id: doublebuffer.cxx 7903 2010-11-28 21:06:39Z matt $"
3 //
4 // Double-buffering test program for the Fast Light Tool Kit (FLTK).
5 //
6 // This demo shows how double buffering helps, by drawing the
7 // window in a particularily bad way.
8 //
9 // The single-buffered window will blink as it updates. The
10 // double buffered one will not. It will take just as long
11 // (or longer) to update, but often it will appear to be faster.
12 //
13 // This demo should work for both the GL and X versions of Fl,
14 // even though the double buffering mechanism is totally different.
15 //
16 // Copyright 1998-2010 by Bill Spitzak and others.
17 //
18 // This library is free software; you can redistribute it and/or
19 // modify it under the terms of the GNU Library General Public
20 // License as published by the Free Software Foundation; either
21 // version 2 of the License, or (at your option) any later version.
22 //
23 // This library is distributed in the hope that it will be useful,
24 // but WITHOUT ANY WARRANTY; without even the implied warranty of
25 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
26 // Library General Public License for more details.
27 //
28 // You should have received a copy of the GNU Library General Public
29 // License along with this library; if not, write to the Free Software
30 // Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307
31 // USA.
32 //
33 // Please report all bugs and problems on the following page:
34 //
35 // http://www.fltk.org/str.php
36 //
37
38 #include <FL/Fl.H>
39 #include <FL/Fl_Single_Window.H>
40 #include <FL/Fl_Double_Window.H>
41 #include <FL/Fl_Box.H>
42 #include <FL/fl_draw.H>
43 #include <FL/Fl_Hor_Slider.H>
44 #include <stdlib.h>
45 #include <FL/math.h>
46 #include <stdio.h>
47
48 // this purposely draws each line 10 times to be slow:
star(int w,int h,int n)49 void star(int w, int h, int n) {
50 fl_push_matrix();
51 fl_translate(w/2, h/2);
52 fl_scale(w/2, h/2);
53 for (int i = 0; i < n; i++) {
54 for (int j = i+1; j < n; j++)/* for (int k=0; k<10; k++)*/ {
55 fl_begin_line();
56 fl_vertex(cos(2*M_PI*i/n+.1), sin(2*M_PI*i/n+.1));
57 fl_vertex(cos(2*M_PI*j/n+.1), sin(2*M_PI*j/n+.1));
58 fl_end_line();
59 }
60 }
61 fl_pop_matrix();
62 }
63
64 int sides[2] = {20,20};
65
slider_cb(Fl_Widget * o,long v)66 void slider_cb(Fl_Widget* o, long v) {
67 sides[v] = int(((Fl_Slider*)o)->value());
68 o->parent()->redraw();
69 }
70
bad_draw(int w,int h,int which)71 void bad_draw(int w,int h,int which) {
72 // for (int i=0; i<10; i++) {
73 // fl_color(7); fl_rectf(0,0,w,h); fl_color(0); star(w,h);
74 // fl_color(0); fl_rectf(0,0,w,h); fl_color(7); star(w,h);
75 // }
76 fl_color(FL_BLACK); fl_rectf(0,0,w,h);
77 fl_color(FL_WHITE); star(w,h,sides[which]);
78 // for (int x=0; x<sides[which]; x++) for (int y=0; y<sides[which]; y++)
79 //fl_draw_box(FL_UP_BOX, 10*x, 10*y, 25,25, FL_GRAY);
80 }
81
82 class single_blink_window : public Fl_Single_Window {
draw()83 void draw() {bad_draw(w(),h(),0); draw_child(*child(0));}
84 public:
single_blink_window(int x,int y,int w,int h,const char * l)85 single_blink_window(int x, int y,int w,int h,const char *l)
86 : Fl_Single_Window(x,y,w,h,l) {resizable(this);}
87 };
88
89 class double_blink_window : public Fl_Double_Window {
draw()90 void draw() {bad_draw(w(),h(),1); draw_child(*child(0));}
91 public:
double_blink_window(int x,int y,int w,int h,const char * l)92 double_blink_window(int x, int y, int w,int h,const char *l)
93 : Fl_Double_Window(x,y,w,h,l) {resizable(this);}
94 };
95
main(int argc,char ** argv)96 int main(int argc, char **argv) {
97 if (!Fl::visual(FL_DOUBLE))
98 printf("Xdbe not supported, faking double buffer with pixmaps.\n");
99 Fl_Window w01(420,420,"Fl_Single_Window"); w01.box(FL_FLAT_BOX);
100 single_blink_window w1(10,10,400,400,"Fl_Single_Window");
101 w1.box(FL_FLAT_BOX); w1.color(FL_BLACK); //w1.position(100,200);
102 Fl_Hor_Slider slider0(20,370,360,25);
103 slider0.range(2,30);
104 slider0.step(1);
105 slider0.value(sides[0]);
106 slider0.callback(slider_cb, 0);
107 w1.end();
108 w01.end();
109 Fl_Window w02(420,420,"Fl_Double_Window"); w02.box(FL_FLAT_BOX);
110 double_blink_window w2(10,10,400,400,"Fl_Double_Window");
111 w2.box(FL_FLAT_BOX); w2.color(FL_BLACK); //w2.position(600,200);
112 Fl_Hor_Slider slider1(20,370,360,25);
113 slider1.range(2,30);
114 slider1.step(1);
115 slider1.value(sides[0]);
116 slider1.callback(slider_cb, 1);
117 w2.end();
118 w02.end();
119 w01.show(argc, argv);
120 w1.show();
121 w02.show();
122 w2.show();
123 return Fl::run();
124 }
125
126 //
127 // End of "$Id: doublebuffer.cxx 7903 2010-11-28 21:06:39Z matt $".
128 //
129