fltk/test/image.cxx

147 lines
3.9 KiB
C++

//
// Fl_Image test program for the Fast Light Tool Kit (FLTK).
//
// Notice that Fl_Image is for a static, multiple-reuse image, such
// as an icon or postage stamp. Use fl_draw_image to go directly
// from an buffered image that changes often.
//
// Copyright 1998-2021 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_Double_Window.H>
#include <FL/Fl_Button.H>
#include <FL/Fl_Image.H>
#include <stdio.h>
#include <stdlib.h>
#include <math.h>
int width = 100;
int height = 100;
uchar *image;
void make_image() {
image = new uchar[4*width*height];
uchar *p = image;
for (int y = 0; y < height; y++) {
double Y = double(y)/(height-1);
for (int x = 0; x < width; x++) {
double X = double(x)/(width-1);
*p++ = uchar(255*((1-X)*(1-Y))); // red in upper-left
*p++ = uchar(255*((1-X)*Y)); // green in lower-left
*p++ = uchar(255*(X*Y)); // blue in lower-right
X -= 0.5;
Y -= 0.5;
int alpha = (int)(255 * sqrt(X * X + Y * Y));
if (alpha < 255) *p++ = uchar(alpha); // alpha transparency
else *p++ = 255;
Y += 0.5;
}
}
}
#include <FL/Fl_Toggle_Button.H>
Fl_Toggle_Button *leftb,*rightb,*topb,*bottomb,*insideb,*overb,*inactb;
Fl_Button *b;
Fl_Double_Window *w;
void button_cb(Fl_Widget *,void *) {
int i = 0;
if (leftb->value()) i |= FL_ALIGN_LEFT;
if (rightb->value()) i |= FL_ALIGN_RIGHT;
if (topb->value()) i |= FL_ALIGN_TOP;
if (bottomb->value()) i |= FL_ALIGN_BOTTOM;
if (insideb->value()) i |= FL_ALIGN_INSIDE;
if (overb->value()) i |= FL_ALIGN_TEXT_OVER_IMAGE;
b->align(i);
if (inactb->value()) b->deactivate();
else b->activate();
w->redraw();
}
#include <FL/platform.H>
#if defined(FLTK_USE_X11)
#include "list_visuals.cxx"
#endif
int visid = -1;
int arg(int argc, char **argv, int &i) {
if (argv[i][1] == 'v') {
if (i+1 >= argc) return 0;
visid = atoi(argv[i+1]);
i += 2;
return 2;
}
return 0;
}
int main(int argc, char **argv) {
#if defined(FLTK_USE_X11)
int i = 1;
Fl::args(argc,argv,i,arg);
if (visid >= 0) {
fl_open_display();
XVisualInfo templt; int num;
templt.visualid = visid;
fl_visual = XGetVisualInfo(fl_display, VisualIDMask, &templt, &num);
if (!fl_visual) {
fprintf(stderr, "No visual with id %d, use one of:\n",visid);
list_visuals();
exit(1);
}
fl_colormap = XCreateColormap(fl_display, RootWindow(fl_display,fl_screen),
fl_visual->visual, AllocNone);
fl_xpixel(FL_BLACK); // make sure black is allocated in overlay visuals
} else {
Fl::visual(FL_RGB);
}
#endif
Fl_Double_Window window(400,400); ::w = &window;
window.color(FL_WHITE);
Fl_Button b(140,160,120,120,"Image w/Alpha"); ::b = &b;
Fl_RGB_Image *rgb;
Fl_Image *dergb;
make_image();
rgb = new Fl_RGB_Image(image, width, height,4);
dergb = rgb->copy();
dergb->inactive();
b.image(rgb);
b.deimage(dergb);
leftb = new Fl_Toggle_Button(25,50,50,25,"left");
leftb->callback(button_cb);
rightb = new Fl_Toggle_Button(75,50,50,25,"right");
rightb->callback(button_cb);
topb = new Fl_Toggle_Button(125,50,50,25,"top");
topb->callback(button_cb);
bottomb = new Fl_Toggle_Button(175,50,50,25,"bottom");
bottomb->callback(button_cb);
insideb = new Fl_Toggle_Button(225,50,50,25,"inside");
insideb->callback(button_cb);
overb = new Fl_Toggle_Button(25,75,100,25,"text over");
overb->callback(button_cb);
inactb = new Fl_Toggle_Button(125,75,100,25,"inactive");
inactb->callback(button_cb);
window.resizable(window);
window.end();
window.show(argc, argv);
return Fl::run();
}