hyland@esosun.UUCP (Steve Hyland) (05/17/88)
X Window System
X11R2 Ada Binding
At long last, we are happy to announce that Revision 2 of the X_Ada binding
is now going out the door (phew!). This binding is much improved, incorporating
the comments of previous users as well as all the bugs we know about.
Changes you are likely to notice:
1) Masks are now boolean arrays. This should not affect your code since we
had defined "or" and "and" in the previous release.
2) The specs no longer contain record representation specs. These still
exist, but are in the package body now. The dependence upon C is
more transparent to you.
3) Calls which return only a single value are now, logically, functions.
This change, for those who have written code already, should be the
most significant change in the spec.
4) We have added all calls that MIT added to their release 2. The only
calls missing are If_Event, Peek_If_Event and one other If call. These
will make it into Revision 3.
5) Other things we are not supporting (at this release) are the extension
mechanism and the resource manager. The resource manager may come out
with the toolkit.
6) We have reduced the number of compilation units to the following:
x_lib_.a -- X_Windows specification
x_keysyms_.a -- X_Keysyms specification
x_int_.a -- X_Windows_Interface specification
x_lib.a -- X_Windows body
x_events.a -- X_Windows.Events body
x_keyboard.a -- X_Windows.Keyboard body
x_atoms.a -- X_Windows.Atoms body
x_colors.a -- X_Windows.Colors body
x_cursors.a -- X_Windows.Cursors body
x_cutpaste.a -- X_Windows.Cut_And_Paste body
x_fonts.a -- X_Windows.Fonts body
x_graphic.a -- X_Windows.Graphic_Output body
x_regions.a -- X_Windows.Regions body
x_win_mgr.a -- X_Windows.Window_Manager body
7) String_Lists are much easier to use. They are still access types to
arrays of string_pointers but no longer private.
8) We added a function Get_Command_Line_Arguments to enable you to have
applications which use arguments. This returns a string_list. Parsing
the list is up to you. This function is easily rewritten for your
favorite compiler.
9) The C binding has six calls for text output. We have nine. Three of
these are overloaded to allow you to output ASCII strings or X_Strings
(arrays of X_Character). X_Character is in the range 0 .. 255 and
represents most extended fonts except things like Kanji. These calls
are Draw_String, Draw_Text and Draw_Image_String.
10) Mark has been hard at work cleaning up some of his examples for you.
We have included Hello_World.ada and Sketch_Pad.ada. This is not the
only thing he does so if you have stylistic comments, please send
them to /dev/null. One thing you should look at in Sketch_Pad; we
provide three ways to set the background pixmap:
- Use the command line argument -b with the name of a bitmap you
have created using the bitmap editor which came with your MIT
distribution. Ex., Sketch_Pad -b gray
- If you don't specify a bitmap as an argument, Sketch_Pad
looks for a file called ".sketchpadrc", created with the
same bitmap editor.
- If you don't specify a bitmap and .sketchpadrc is not found,
or if you do specify a bitmap and it is not found, Sketch_Pad
creates a pixmap from a byte array declared locally.
The reason I point this out is because these are the correct way to
handle bitmaps (not with the Image type).
11) The interface portion (X_Windows_Interface) is about as portable as
its going to get right now. How portable is it ? Well, Telesoft
got Sketch_Pad and Hello_World up and running within two days of
receiving the code. Thanks to Dave Emery at MITRE for his comments
and suggestions here.
Now for all of those who want the distribution, we ask that you do the
following; FTP from the AJPO repository if you have FTP capability. Otherwise,
we will be happy to cut a tape for you BUT, we must charge you $150 to do
so. And I STRONGLY encourage you to FTP instead. Cutting these tapes takes
a lot of time for us.
Now for the toolkit. I would like to have shipped this at the same time
but we're just not ready yet. Part of the delay has been the transition
to revision 2. We couldn't test things until we had X_Lib working. So
we hope to have this out Real Soon Now (before the end of May). For those
of you who are unaware, it is written on top of Xr (Xray) from Hewlett
Packard and it is not extensible - that is to say, if you were hoping
to roll your own widgets, we are not yet supporting that feature.
Our next bit of work is the implementation down to the protocol level of
X_Lib. That will free you of the dependence upon the C binding to X_Lib
but not to the server (obviously). This means that your Ada client will
directly connect to the server through sockets (in UNIX) and generate
the protocol packets without using the C calls. Following that is a
full Ada toolkit. Watch for more discussion on this. Suffice it to say
the Ada toolkit will be extensible, will support tasking, will provide
the same set of widgets as Xr and will allow you to associate procedures
or task entries to be executed as a call back routine.
Finally, feel free to submit bug reports to us. We'll try to fix them as
we have time.
Steve Hyland
Mark Nelson
SAIC
(619) 458-2656