fltk/test/doublebuffer.cxx

112 lines
3.4 KiB
C++

//
// Double-buffering test program for the Fast Light Tool Kit (FLTK).
//
// This demo shows how double buffering helps, by drawing the
// window in a particularily bad way.
//
// The single-buffered window will blink as it updates. The
// double buffered one will not. It will take just as long
// (or longer) to update, but often it will appear to be faster.
//
// This demo should work for both the GL and X versions of Fl,
// even though the double buffering mechanism is totally different.
//
// Copyright 1998-2010 by Bill Spitzak and others.
//
// This library is free software. Distribution and use rights are outlined in
// the file "COPYING" which should have been included with this file. If this
// file is missing or damaged, see the license at:
//
// https://www.fltk.org/COPYING.php
//
// Please see the following page on how to report bugs and issues:
//
// https://www.fltk.org/bugs.php
//
#include <FL/Fl.H>
#include <FL/Fl_Single_Window.H>
#include <FL/Fl_Double_Window.H>
#include <FL/Fl_Box.H>
#include <FL/fl_draw.H>
#include <FL/Fl_Hor_Slider.H>
#include <stdlib.h>
#include <FL/math.h>
#include <stdio.h>
// this purposely draws each line 10 times to be slow:
void star(int w, int h, int n) {
fl_push_matrix();
fl_translate(w/2, h/2);
fl_scale(w/2, h/2);
for (int i = 0; i < n; i++) {
for (int j = i+1; j < n; j++)/* for (int k=0; k<10; k++)*/ {
fl_begin_line();
fl_vertex(cos(2*M_PI*i/n+.1), sin(2*M_PI*i/n+.1));
fl_vertex(cos(2*M_PI*j/n+.1), sin(2*M_PI*j/n+.1));
fl_end_line();
}
}
fl_pop_matrix();
}
int sides[2] = {20,20};
void slider_cb(Fl_Widget* o, long v) {
sides[v] = int(((Fl_Slider*)o)->value());
o->parent()->redraw();
}
void bad_draw(int w,int h,int which) {
// for (int i=0; i<10; i++) {
// fl_color(7); fl_rectf(0,0,w,h); fl_color(0); star(w,h);
// fl_color(0); fl_rectf(0,0,w,h); fl_color(7); star(w,h);
// }
fl_color(FL_BLACK); fl_rectf(0,0,w,h);
fl_color(FL_WHITE); star(w,h,sides[which]);
// for (int x=0; x<sides[which]; x++) for (int y=0; y<sides[which]; y++)
//fl_draw_box(FL_UP_BOX, 10*x, 10*y, 25,25, FL_GRAY);
}
class single_blink_window : public Fl_Single_Window {
void draw() FL_OVERRIDE {bad_draw(w(),h(),0); draw_child(*child(0));}
public:
single_blink_window(int x, int y,int w,int h,const char *l)
: Fl_Single_Window(x,y,w,h,l) {resizable(this);}
};
class double_blink_window : public Fl_Double_Window {
void draw() FL_OVERRIDE {bad_draw(w(),h(),1); draw_child(*child(0));}
public:
double_blink_window(int x, int y, int w,int h,const char *l)
: Fl_Double_Window(x,y,w,h,l) {resizable(this);}
};
int main(int argc, char **argv) {
Fl_Window w01(420,420,"Fl_Single_Window"); w01.box(FL_FLAT_BOX);
single_blink_window w1(10,10,400,400,"Fl_Single_Window");
w1.box(FL_FLAT_BOX); w1.color(FL_BLACK); //w1.position(100,200);
Fl_Hor_Slider slider0(20,370,360,25);
slider0.range(2,30);
slider0.step(1);
slider0.value(sides[0]);
slider0.callback(slider_cb, 0);
w1.end();
w01.end();
Fl_Window w02(420,420,"Fl_Double_Window"); w02.box(FL_FLAT_BOX);
double_blink_window w2(10,10,400,400,"Fl_Double_Window");
w2.box(FL_FLAT_BOX); w2.color(FL_BLACK); //w2.position(600,200);
Fl_Hor_Slider slider1(20,370,360,25);
slider1.range(2,30);
slider1.step(1);
slider1.value(sides[0]);
slider1.callback(slider_cb, 1);
w2.end();
w02.end();
w01.show(argc, argv);
w1.show();
w02.show();
w2.show();
return Fl::run();
}