Animated GIF support (Fl_Anim_GIF_Image class) (#375)

1 files changed, 303 insertions, 0 deletions

diff --git a/examples/animgifimage.cxx b/examples/animgifimage.cxx
new file mode 100644
index 000000000..515b76b65
--- /dev/null
+++ b/examples/animgifimage.cxx
@@ -0,0 +1,303 @@
+//
+//  Test program for displaying animated GIF files using the
+//  Fl_Anim_GIF_Image class.
+//
+#include <FL/Fl_Anim_GIF_Image.H>
+
+#include <FL/Fl_Double_Window.H>
+#include <FL/Fl_File_Chooser.H>
+#include <FL/Fl_Shared_Image.H>
+#include <FL/Fl_Tiled_Image.H>
+#include <stdlib.h>
+
+static int g_good_count = 0, g_bad_count = 0, g_frame_count = 0;
+
+static const Fl_Color BackGroundColor = FL_GRAY; // use e.g. FL_RED to see
+                                                 // transparent parts better
+static const double RedrawDelay = 1./20;         // interval [sec] for forced redraw
+
+static void quit_cb(Fl_Widget* w_, void*) {
+  exit(0);
+}
+
+static void set_title(Fl_Window *win, Fl_Anim_GIF_Image *animgif) {
+  char buf[200];
+  snprintf(buf, sizeof(buf), "%s (%d frames)  %2.2fx", fl_filename_name(animgif->name()),
+          animgif->frames(), animgif->speed());
+  if (animgif->frame_uncache())
+    strcat(buf, " U");
+  win->copy_label(buf);
+  win->copy_tooltip(buf);
+}
+
+static void cb_forced_redraw(void *d) {
+  Fl_Window *win = Fl::first_window();
+  while (win) {
+    if (!win->menu_window())
+      win->redraw();
+    win = Fl::next_window(win);
+  }
+  if (Fl::first_window())
+    Fl::repeat_timeout(RedrawDelay, cb_forced_redraw);
+}
+
+Fl_Window *openFile(const char *name, char *flags, bool close = false) {
+  // determine test options from 'flags'
+  bool uncache = strchr(flags, 'u');
+  char *d = flags - 1;
+  int debug = 0;
+  while ((d = strchr(++d, 'd'))) debug++;
+  bool optimize_mem = strchr(flags, 'm');
+  bool desaturate = strchr(flags, 'D');
+  bool average = strchr(flags, 'A');
+  bool test_tiles = strchr(flags, 'T');
+  bool test_forced_redraw = strchr(flags, 'f');
+  char *r = strchr(flags, 'r');
+  bool resizable = r && !test_tiles;
+  double scale = 1.0;
+  if (r && resizable) scale = atof(r+1);
+  if (scale <= 0.1 || scale > 5)
+    scale = resizable ? 0.7 : 1.0;
+
+  // setup window
+  Fl::remove_timeout(cb_forced_redraw);
+  Fl_Double_Window *win = new Fl_Double_Window(300, 300);
+  win->color(BackGroundColor);
+  if (close)
+    win->callback(quit_cb);
+  printf("Loading '%s'%s%s ... ", name,
+    uncache ? " (uncached)" : "",
+    optimize_mem ? " (optimized)" : "");
+
+  // create a canvas for the animation
+  Fl_Box *canvas = test_tiles ? 0 : new Fl_Box(0, 0, 0, 0); // canvas will be resized by animation
+  Fl_Box *canvas2 = 0;
+  unsigned short gif_flags = debug ? Fl_Anim_GIF_Image::LOG_FLAG : 0;
+  if (debug > 1)
+    gif_flags |= Fl_Anim_GIF_Image::DEBUG_FLAG;
+  if (optimize_mem)
+    gif_flags |= Fl_Anim_GIF_Image::OPTIMIZE_MEMORY;
+
+  // create animation, specifying this canvas as display widget
+  Fl_Anim_GIF_Image *animgif = new Fl_Anim_GIF_Image(name, canvas, gif_flags);
+  bool good( animgif->ld() == 0  && animgif->valid() );
+  printf("%s: %d x %d (%d frames) %s\n",
+    animgif->name(), animgif->w(), animgif->h(), animgif->frames(), good ? "OK" : "ERROR");
+  // for the statistics (when run on testsuite):
+  g_good_count += good;
+  g_bad_count += !good;
+  g_frame_count += animgif->frames();
+
+  win->user_data(animgif); // store address of image (see note in main())
+
+  // exercise the optional tests on the animation
+  animgif->frame_uncache(uncache);
+  if (scale != 1.0) {
+    animgif->resize(scale);
+    printf("TEST: resized %s by %.2f to %d x %d\n", animgif->name(), scale, animgif->w(), animgif->h());
+  }
+  if (average) {
+    printf("TEST: color_average %s\n", animgif->name());
+    animgif->color_average(FL_GREEN, 0.5); // currently hardcoded
+  }
+  if (desaturate) {
+    printf("TEST: desaturate %s\n", animgif->name());
+    animgif->desaturate();
+  }
+  int W = animgif->w();
+  int H = animgif->h();
+  if (animgif->frames()) {
+    if (test_tiles) {
+      // demonstrate a way how to use the animation with Fl_Tiled_Image
+      printf("TEST: use %s as tiles\n", animgif->name());
+      W *= 2;
+      H *= 2;
+      Fl_Tiled_Image *tiled_image = new Fl_Tiled_Image(animgif);
+      Fl_Group *group = new Fl_Group(0, 0, win->w(), win->h());
+      group->image(tiled_image);
+      group->align(FL_ALIGN_INSIDE);
+      animgif->canvas(group, Fl_Anim_GIF_Image::DONT_RESIZE_CANVAS | Fl_Anim_GIF_Image::DONT_SET_AS_IMAGE );
+      win->resizable(group);
+    } else {
+      // demonstrate a way how to use same animation in another canvas simultaneously:
+      // as the current implementation allows only automatic redraw of one canvas..
+      if (test_forced_redraw) {
+        if (W < 400) {
+          printf("TEST: open %s in another animation with application redraw\n", animgif->name());
+          canvas2 = new Fl_Box(W, 0, animgif->w(), animgif->h()); // another canvas for animation
+          canvas2->image(animgif); // is set to same animation!
+          W *= 2;
+          Fl::add_timeout(RedrawDelay, cb_forced_redraw); // force periodic redraw
+        }
+      }
+    }
+    // make window resizable (must be done before show())
+    if (resizable && canvas && !test_tiles) {
+      win->resizable(win);
+    }
+    win->size(W, H); // change to actual size of canvas
+    // start the animation
+    win->end();
+    win->show();
+    win->wait_for_expose();
+    set_title(win, animgif);
+    if (resizable && !test_tiles) {
+      // need to reposition the widgets (have been moved by setting resizable())
+      if (canvas && canvas2) {
+        canvas->resize(0, 0, W/2, canvas->h());
+        canvas2->resize(W/2, 0, W/2, canvas2->h());
+      }
+      else if (canvas) {
+        canvas->resize(0, 0, animgif->canvas_w(), animgif->canvas_h());
+      }
+    }
+    win->init_sizes(); // IMPORTANT: otherwise weird things happen at Ctrl+/- scaling
+  } else {
+    delete win;
+    return 0;
+  }
+  if (debug >=3) {
+    // open each frame in a separate window
+    for (int i = 0; i < animgif->frames(); i++) {
+      char buf[200];
+      snprintf(buf, sizeof(buf), "Frame #%d", i + 1);
+      Fl_Double_Window *win = new Fl_Double_Window(animgif->w(), animgif->h());
+      win->copy_tooltip(buf);
+      win->copy_label(buf);
+      win->color(BackGroundColor);
+      int w = animgif->image(i)->w();
+      int h = animgif->image(i)->h();
+      // in 'optimize_mem' mode frames must be offsetted to canvas
+      int x = (w == animgif->w() && h == animgif->h()) ? 0 : animgif->frame_x(i);
+      int y = (w == animgif->w() && h == animgif->h()) ? 0 : animgif->frame_y(i);
+      Fl_Box *b = new Fl_Box(x, y, w, h);
+      // get the frame image
+      b->image(animgif->image(i));
+      win->end();
+      win->show();
+    }
+  }
+  return win;
+}
+
+#include <FL/filename.H>
+bool openDirectory(const char *dir, char *flags) {
+  dirent **list;
+  int nbr_of_files = fl_filename_list(dir, &list, fl_alphasort);
+  if (nbr_of_files <= 0)
+    return false;
+  int cnt = 0;
+  for (int i = 0; i < nbr_of_files; i++) {
+    char buf[512];
+    const char *name = list[i]->d_name;
+    if (!strcmp(name, ".") || !strcmp(name, "..")) continue;
+    const char *p = strstr(name, ".gif");
+    if (!p) p = strstr(name, ".GIF");
+    if (!p) continue;
+    if (*(p+4)) continue; // is no extension!
+    snprintf(buf, sizeof(buf), "%s/%s", dir, name);
+    if (strstr(name, "debug"))	// hack: when name contains 'debug' open single frames
+      strcat(flags, "d");
+    if (openFile(buf, flags, cnt == 0))
+      cnt++;
+  }
+  return cnt != 0;
+}
+
+static void change_speed(double delta) {
+  Fl_Widget *below = Fl::belowmouse();
+  if (below && below->image()) {
+    Fl_Anim_GIF_Image *animgif = 0;
+    // Q: is there a way to determine Fl_Tiled_Image without using dynamic cast?
+    Fl_Tiled_Image *tiled = dynamic_cast<Fl_Tiled_Image *>(below->image());
+    animgif = tiled ?
+              dynamic_cast<Fl_Anim_GIF_Image *>(tiled->image()) :
+              dynamic_cast<Fl_Anim_GIF_Image *>(below->image());
+    if (animgif && animgif->playing()) {
+      double speed = animgif->speed();
+      if (!delta) speed = 1.;
+      else speed += delta;
+      if (speed < 0.1) speed = 0.1;
+      if (speed > 10) speed = 10;
+      animgif->speed(speed);
+      set_title(below->window(), animgif);
+    }
+  }
+}
+
+static int events(int event) {
+  if (event == FL_SHORTCUT) {
+    if (Fl::event_key() == '+')
+      change_speed(0.1);
+    else if (Fl::event_key() == '-')
+      change_speed(-0.1);
+    else if (Fl::event_key() == '0')
+      change_speed(0);
+    else
+      return 0;
+    return 1;
+  }
+  return 0;
+}
+
+static const char testsuite[] = "testsuite";
+
+int main(int argc, char *argv[]) {
+  fl_register_images();
+  Fl::add_handler(events);
+  char *openFlags = (char *)calloc(1024, 1);
+  if (argc > 1) {
+    // started with argumemts
+    if (strstr(argv[1], "-h")) {
+      printf("Usage:\n"
+             "   -t [directory] [-{flags}] open all files in directory (default name: %s) [with options]\n"
+             "   filename [-{flags}] open single file [with options] \n"
+             "   No arguments open a fileselector\n"
+             "   {flags} can be: d=debug mode, u=uncached, D=desaturated, A=color averaged, T=tiled\n"
+             "                   m=minimal update, r[scale factor]=resize by 'scale factor'\n"
+             "   Use keys '+'/'-/0' to change speed of the active image (belowmouse).\n", testsuite);
+      exit(1);
+    }
+    for (int i = 1; i < argc; i++) {
+      if (argv[i][0] == '-')
+        strcat(openFlags, &argv[i][1]);
+    }
+    if (strchr(openFlags, 't')) { // open all GIF-files in a given directory
+      const char *dir = testsuite;
+      for (int i = 2; i < argc; i++)
+        if (argv[i][0] != '-')
+          dir = argv[i];
+      openDirectory(dir, openFlags);
+      printf("Summary: good=%d, bad=%d, frames=%d\n", g_good_count, g_bad_count, g_frame_count);
+    } else { // open given file(s)
+      for (int i = 1; i < argc; i++)
+        if (argv[i][0] != '-')
+          openFile(argv[i], openFlags, strchr(openFlags, 'd'));
+    }
+  } else {
+    // started without arguments: choose file
+    Fl_GIF_Image::animate = true; // create animated shared .GIF images (e.g. file chooser)
+    while (1) {
+      Fl::add_timeout(0.1, cb_forced_redraw); // animate images in chooser
+      const char *filename = fl_file_chooser("Select a GIF image file","*.{gif,GIF}", NULL);
+      Fl::remove_timeout(cb_forced_redraw);
+      if (!filename)
+        break;
+      Fl_Window *win = openFile(filename, openFlags);
+      Fl::run();
+      // delete last window (which is now just hidden) to test destructors
+      // NOTE: it is essential that *before* doing this also the
+      //       animated image is destroyed, otherwise it will crash
+      //       because it's canvas will be gone.
+      //       In order to keep this demo simple, the adress of the
+      //       Fl_Anim_GIF_Image has been stored in the window's user_data.
+      //       In a real-life application you will probably store
+      //       it somewhere in the window's or canvas' object and destroy
+      //       the image in the window's or canvas' destructor.
+      if (win && win->user_data())
+        delete ((Fl_Anim_GIF_Image *)win->user_data());
+      delete win;
+    }
+  }
+  return Fl::run();
+}