272 lines
10 KiB
HTML
272 lines
10 KiB
HTML
<HTML>
|
|
<BODY>
|
|
|
|
<H1 ALIGN=RIGHT><A NAME="forms">E - Forms Compatibility</A></H1>
|
|
|
|
This appendix describes the Forms compatibility included with FLTK.
|
|
|
|
<H2>Importing Forms Layout Files</H2>
|
|
|
|
<a href="#FLUID">FLUID</a> can read the .fd files put out by all
|
|
versions of Forms and XForms fdesign. However, it will mangle them a
|
|
bit, but it prints a warning message about anything it does not
|
|
understand. FLUID cannot write fdesign files, so you should save to a
|
|
new name so you don't write over the old one.
|
|
|
|
<p>You will need to edit your main code considerably to get it to link
|
|
with the output from FLUID. If you are not interested in this you may
|
|
have more immediate luck with the forms compatibility header,
|
|
<tt><FL/forms.H></tt>.
|
|
|
|
<H2>Using the Compatibility Header File</H2>
|
|
|
|
You should be able to compile existing Forms or XForms source code
|
|
by changing the include directory switch to your compiler so that the
|
|
<tt>forms.h</tt> file supplied with FLTK is included. Take a look at
|
|
<tt>forms.h</tt> to see how it works, but the basic trick is lots of
|
|
inline functions. Most of the XForms demo programs work without
|
|
changes.
|
|
|
|
<p>You will also have to compile your Forms or XForms program using a
|
|
C++ compiler. The FLTK library does not provide C bindings or header
|
|
files.
|
|
|
|
<p>Although FLTK was designed to be compatable with the GL Forms library
|
|
(version 0.3 or so), XForms has bloated severely and it's interface is
|
|
X-specific. Therefore, XForms compatibility is no longer a goal of
|
|
FLTK. Compatibility was limited to things that were free, or that
|
|
would add code that would not be linked in if the feature is unused,
|
|
or that was not X-specific.
|
|
|
|
<p>To use any new features of FLTK, you should rewrite your code to not
|
|
use the inline functions and instead use "pure" FLTK. This will make
|
|
it a lot cleaner and make it easier to figure out how to call the FLTK
|
|
functions. Unfortunately this conversion is harder than expected and
|
|
even Digital Domain's inhouse code still uses <tt>forms.H</tt> a lot.
|
|
|
|
<h2>Problems you will encounter</h2>
|
|
|
|
<p>Many parts of XForms use X-specific structures like <tt>XEvent</tt>
|
|
in their interface. I did not emulate these! Unfortunately these
|
|
features (such as the "canvas" widget) are needed by most large
|
|
programs. You will need to rewrite these to use FLTK subclasses.
|
|
|
|
<p><a href="#Fl_Free"><tt>Fl_Free</tt></a> widgets emulate the
|
|
<i>old</i> Forms "free" widget. It may be useful for porting programs
|
|
that change the <tt>handle()</tt> function on widgets, but you will
|
|
still need to rewrite things.
|
|
|
|
<p><a href="#Fl_Timer"><tt>Fl_Timer</tt></a> widgets are provided to
|
|
emulate the XForms timer. These work, but are quite inefficient and
|
|
inaccurate compared to using <a
|
|
href="#add_timeout"><tt>Fl::add_timeout()</tt></a>.
|
|
|
|
<p><i>All instance variables are hidden.</i>
|
|
If you directly refer to the x, y, w, h, label, or other fields of
|
|
your Forms widgets you will have to add empty parenthesis after each
|
|
reference. The easiest way to do this is to globally replace "->x"
|
|
with "->x()", etc. Replace "boxtype" with "box()".
|
|
|
|
<p><tt>const char *</tt> arguments to most FLTK methods are simply
|
|
stored, while Forms would <tt>strdup()</tt> the passed string. This is
|
|
most noticable with the label of widgets. Your program must always
|
|
pass static data such as a string constant or malloc'd buffer to
|
|
<tt>label()</tt>. If you are using labels to display program output
|
|
you may want to try the <a href="#Fl_Output"><tt>Fl_Output</tt></a> widget.
|
|
|
|
<p>The default fonts and sizes are matched to the older GL version of
|
|
Forms, so all labels will draw somewhat larger than an XForms program
|
|
does.
|
|
|
|
<p>fdesign outputs a setting of a "fdui" instance variable to the main
|
|
window. I did not emulate this because I wanted all instance variables
|
|
to be hidden. You can store the same information in the
|
|
<tt>user_data()</tt> field of a window. To do this, search through
|
|
the fdesign output for all occurances of "->fdui" and edit to use
|
|
"->user_data()" instead. This will require casts and is not trivial.
|
|
|
|
<p>The prototype for the functions passed to <tt>fl_add_timeout()</tt>
|
|
and <tt>fl_set_idle_callback()</tt> callback are different.
|
|
|
|
<p><b>All the following XForms calls are missing:</b><p>
|
|
|
|
<ul>
|
|
<li><tt>FL_REVISION</tt>, <tt>fl_library_version()</tt>
|
|
<li><tt>FL_RETURN_DBLCLICK</tt> (use <tt>Fl::event_clicks()</tt>)
|
|
<li><tt>fl_add_signal_callback()</tt>
|
|
<li><tt>fl_set_form_atactivate()</tt> & <tt>fl_set_form_atdeactivate()</tt>
|
|
<li><tt>fl_set_form_property()</tt>
|
|
<li><tt>fl_set_app_mainform()</tt>, <tt>fl_get_app_mainform()</tt>
|
|
<li><tt>fl_set_form_minsize()</tt>, <tt>fl_set_form_maxsize()</tt>
|
|
<li><tt>fl_set_form_event_cmask()</tt>, <tt>fl_get_form_event_cmask()</tt>
|
|
<li><tt>fl_set_form_dblbuffer()</tt>, <tt>fl_set_object_dblbuffer()</tt> (use an
|
|
<tt>Fl_Double_Window</tt> instead)
|
|
<li><tt>fl_adjust_form_size()</tt>
|
|
<li><tt>fl_register_raw_callback()</tt>
|
|
<li><tt>fl_set_object_bw()</tt>, <tt>fl_set_border_width()</tt>
|
|
<li><tt>fl_set_object_resize()</tt>, <tt>fl_set_object_gravity()</tt>
|
|
<li><tt>fl_set_object_shortcutkey()</tt>
|
|
<li><tt>fl_set_object_automatic()</tt>
|
|
<li><tt>fl_get_object_bbox()</tt> (maybe FLTK should do this)
|
|
<li><tt>fl_set_object_prehandler()</tt>, <tt>fl_set_object_posthandler()</tt>
|
|
<li><tt>fl_enumerate_fonts()</tt>
|
|
<li>Most drawing functions
|
|
<li><tt>fl_set_coordunit()</tt> (FLTK uses pixels all the time)
|
|
<li><tt>fl_ringbell()</tt>
|
|
<li><tt>fl_gettime()</tt>
|
|
<li><tt>fl_win*()</tt> (all these functions)
|
|
<li><tt>fl_initialize(argc,argv,x,y,z)</tt> ignores last 3 arguments
|
|
<li><tt>fl_read_bitmapfile()</tt>, <tt>fl_read_pixmapfile()</tt>
|
|
<li><tt>fl_addto_browser_chars()</tt>
|
|
<li><tt>FL_MENU_BUTTON</tt> just draws normally
|
|
<li><tt>fl_set_bitmapbutton_file()</tt>, <tt>fl_set_pixmapbutton_file()</tt>
|
|
<li><tt>FL_CANVAS</tt> objects
|
|
<li><tt>FL_DIGITAL_CLOCK</tt> (comes out analog)
|
|
<li><tt>fl_create_bitmap_cursor()</tt>, <tt>fl_set_cursor_color()</tt>
|
|
<li><tt>fl_set_dial_angles()</tt>
|
|
<li><tt>fl_show_oneliner()</tt>
|
|
<li><tt>fl_set_choice_shortcut(a,b,c)
|
|
<li>command log
|
|
<li>Only some of file selector is emulated
|
|
<li><tt>FL_DATE_INPUT</tt>
|
|
<li><tt>fl_pup*()</tt> (all these functions)
|
|
<li>textbox object (should be easy but I had no sample programs)
|
|
<li>xyplot object
|
|
</ul>
|
|
|
|
<h2>Additional Notes</h2>
|
|
|
|
These notes were written for porting programs written with the older
|
|
IRISGL version of Forms. Most of these problems are the same ones
|
|
encountered when going from old Forms to XForms:
|
|
|
|
<h3>Does Not Run In Background</h3>
|
|
|
|
The IRISGL library always forked when you created the first window, unless
|
|
"foreground()" was called. FLTK acts like "foreground()" is called all
|
|
the time. If you really want the fork behavior do "if (fork())
|
|
exit(0)" right at the start of your program.
|
|
|
|
<h3>You Cannot Use IRISGL windows or fl_queue</h3>
|
|
|
|
If a Forms (not XForms) program if you wanted your own window for
|
|
displaying things you would create a IRISGL window and draw in it,
|
|
periodically calling Forms to check if the user hit buttons on the
|
|
panels. If the user did things to the IRISGL window, you would find
|
|
this out by having the value FL_EVENT returned from the call to Forms.
|
|
|
|
<p>None of this works with FLTK. Nor will it compile, the necessary
|
|
calls are not in the interface.
|
|
|
|
<p>You have to make a subclass of <a
|
|
href="#Fl_Gl_Window"><tt>Fl_Gl_Window</tt></a> and write a <tt>draw()</tt>
|
|
method and <tt>handle()</tt> method. This may require anywhere from a trivial
|
|
to a major rewrite.
|
|
|
|
<p>If you draw into the overlay planes you will have to also write a
|
|
<tt>draw_overlay()</tt> method and call <tt>redraw_overlay()</tt> on the
|
|
OpenGL window.
|
|
|
|
<p>One easy way to hack your program so it works is to make the
|
|
<tt>draw()</tt> and <tt>handle()</tt> methods on your window set some
|
|
static variables, storing what event happened. Then in the main loop
|
|
of your program, call <tt>Fl::wait()</tt> and then check these
|
|
variables, acting on them as though they are events read from
|
|
<tt>fl_queue</tt>.
|
|
|
|
<h3>You Must Use OpenGL to Draw Everything</h3>
|
|
|
|
<p>The file <tt><FL/gl.h></tt> defines replacements for a lot of
|
|
IRISGL calls, translating them to OpenGL. There are much better
|
|
translators available that you might want to investigate.
|
|
|
|
<h3>You Cannot Make Forms Subclasses</h3>
|
|
|
|
Programs that call <tt>fl_make_object</tt> or directly setting the
|
|
handle routine will not compile. You have to rewrite them to use a
|
|
subclass of <tt>Fl_Widget</tt>. It is important to note that the
|
|
<tt>handle()</tt> method is not exactly the same as the
|
|
<tt>handle()</tt> function of Forms. Where a Forms <tt>handle()</tt>
|
|
returned non-zero, your <tt>handle()</tt> must call
|
|
<tt>do_callback()</tt>. And your <tt>handle()</tt> must return non-zero
|
|
if it "understood" the event.
|
|
|
|
<p>An attempt has been made to emulate the "free" widget. This
|
|
appears to work quite well. It may be quicker to modify your subclass
|
|
into a "free" widget, since the "handle" functions match.
|
|
|
|
<p>If your subclass draws into the overlay you are in trouble and will
|
|
have to rewrite things a lot.
|
|
|
|
<h3>You Cannot Use <device.h></h3>
|
|
|
|
If you have written your own "free" widgets you will probably get a
|
|
lot of errors about "getvaluator". You should substitute:
|
|
|
|
<table border=1>
|
|
<tr>
|
|
<th align=center>Forms</th>
|
|
<th align=center>FLTK</th>
|
|
</tr>
|
|
<tr>
|
|
<td>MOUSE_X</td>
|
|
<td>Fl::event_x_root()</td>
|
|
</tr>
|
|
<tr>
|
|
<td>MOUSE_Y</td>
|
|
<td>Fl::event_y_root()</td>
|
|
</tr>
|
|
<tr>
|
|
<td>LEFTSHIFTKEY,RIGHTSHIFTKEY</td>
|
|
<td>Fl::event_shift()</td>
|
|
</tr>
|
|
<tr>
|
|
<td>CAPSLOCKKEY</td>
|
|
<td>Fl::event_capslock()</td>
|
|
</tr>
|
|
<tr>
|
|
<td>LEFTCTRLKEY,RIGHTCTRLKEY</td>
|
|
<td>Fl::event_ctrl()</td>
|
|
</tr>
|
|
<tr>
|
|
<td>LEFTALTKEY,RIGHTALTKEY</td>
|
|
<td>Fl::event_alt()</td>
|
|
</tr>
|
|
<tr>
|
|
<td>MOUSE1,RIGHTMOUSE</td>
|
|
<td>Fl::event_state()&FL_BUTTON3</td>
|
|
</tr>
|
|
<tr>
|
|
<td>MOUSE2,MIDDLEMOUSE</td>
|
|
<td>Fl::event_state()&FL_BUTTON2</td>
|
|
</tr>
|
|
<tr>
|
|
<td>MOUSE3,LEFTMOUSE</td>
|
|
<td>Fl::event_state()&FL_BUTTON1</td>
|
|
</tr>
|
|
</table>
|
|
|
|
Anything else in <tt>getvaluator</tt> and you are on your own...
|
|
|
|
<h3>Font Numbers Are Different</h3>
|
|
|
|
The "style" numbers have been changed because I wanted to insert
|
|
bold-italic versions of the normal fonts. If you use Times, Courier,
|
|
or Bookman to display any text you will get a different font out of
|
|
FLTK. If you are really desperate to fix this use the following code:
|
|
|
|
<ul><pre>
|
|
fl_font_name(3,"*courier-medium-r-no*");
|
|
fl_font_name(4,"*courier-bold-r-no*");
|
|
fl_font_name(5,"*courier-medium-o-no*");
|
|
fl_font_name(6,"*times-medium-r-no*");
|
|
fl_font_name(7,"*times-bold-r-no*");
|
|
fl_font_name(8,"*times-medium-i-no*");
|
|
fl_font_name(9,"*bookman-light-r-no*");
|
|
fl_font_name(10,"*bookman-demi-r-no*");
|
|
fl_font_name(11,"*bookman-light-i-no*");
|
|
</pre></ul>
|
|
|
|
</BODY>
|
|
</HTML>
|