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Microsoft OS/2 SDK 2.0 05-30-1990

IMAGE PORTING APPLICATION
=========================

The purpose of the IMAGE sample is twofold :-

  i) to demonstrate how to port an existing 16-bit application which
  can be run on the toolkit supplied with OS/2 1.2 to 32-bit.

  ii) to demonstrate the Image functionality of the GPI, and the standard
      File Open dialog.

 Looking at each of the above statements in more detail

GPI Image Functions/File Open Dialog
------------------------------------
 This program displays an image using the GpiImage() call. The image
data comes from a file which the user must select using the standard
File Open dialog which is invoked by selecting 'Open...' on the
File submenu.
If the selected image is larger than the maximum picture area, any
part of the image lying off-screen can be scrolled in using the
horizontal and vertical scroll bars. Alternatively, the entire
image can be displayed by stretching or compressing it to fit the
target rectangle. This is the way the image is displayed initially.

 An image-data file comprises a file header (which contains the
image width and height in pels) and the pel data itself (which
describes the on and off settings of the pels in the image).

 An image-data file has the following format:

                    IMAGE WIDTH (in BYTES)
 BYTE    0          1          2          3         4
   -------------------------------------------------------
   | <space>   |  <space> | <space>  | <space>  | Comma  |
   | or ASCII  | or ASCII | or ASCII | or ASCII |   ,    |
   |  digit    |  digit   |  digit   |  digit   |        |
   |(Thousands)|(Hundreds)| (Tens)   |  (Ones)  |        |
   -------------------------------------------------------


           IMAGE HEIGHT (in PELS)
 BYTE    5          6          7          8
   ----------------------------------------------
   | <space>   | <space>  | <space>  | <space>  |
   | or ASCII  | or ASCII | or ASCII | or ASCII |
   |  digit    |  digit   |  digit   |  digit   |
   |(Thousands)|(Hundreds)|  (Tens)  |  (Ones)  |
   ----------------------------------------------


                      IMAGE DATA
 BYTE    10         11                      End of File
    --------------------------------------------------
    |          |          |                          |
    |  Binary  |  Binary  |       . . . . . .        |
    |  data    |  data    |                          |
    |          |          |                          |
    --------------------------------------------------


Porting to 32-Bit
-----------------
  It details the intermediate stages to achieve
the port, and as a result there are more than one .MAK/.DEF file in order
to build all versions of the IMAGE application. Initially for the June
SDK there are the following groups of .MAK/.DEF files

  a) IMAGE16.MAK/.DEF - pure 16-bit application that can be compiled using
                        the OS/2 1.2 tools/headers/libraries

  b) IMAGES1.MAK/.DEF - Port to 32-bit : Stage 1 - This involves recompiling
                        the original source using the OS/2 2.0 headers and
                        the 32-bit tools/libraries for 32-bit source
                        files, and 16-bit tools/libraries for the 16-bit
                        source file. Note: the 16-bit utility routines are
                        primarily for demonstration purposes only, and should
                        not be considered for real applications in their
                        current form .

  c) IMAGE32.MAK/.DEF - pure 32-bit application that can be compiled using
                        the OS/2 2.0 tools/headers/libraries and using the
                        INCL_32 compiler define.

Each of these .MAK/.DEF files will produce an executable file of the same
name (ie IMAGE16.EXE ...).

Note: The IMAGE16.EXE/IMAGES1.EXE have a dependency on an OS/2 1.2 toolkit
      being available locally since they need 16-bit compilers/linkers.



ORGANIZATION OF SOURCE FILES
============================

Here is list of the source files included in the image application
and their general purpose.

    img_main.h - application constants
    img_xtrn.h - external variable and function declarations
    img_help.h - help panel ids
    img_dlg.h  - dialog box constants and item ids.  This file is designed
                 to be used with the dialog editor.

    img_main.c - main function, main window procedure
                 and Exit List processing routines
    img_init.c - initialization
    img_file.c - routines for processing File menu items
    img_view.c - routines for processing View menu items
    img_util.c - utility routines (ie memory allocation/de-allocation)
    img_size.c - routines for sizing/scrolling
    img_dlg.c  - application specific dialog boxes
    img_help.c - help manager functions
    img_pnt.c  - routines for painting the main window
    img_menu.c - routines for menu handling
    img_data.c - global data declarations

    img_main.rc - main resource file containing menus, stringtable, etc.
    img_help.rc - resource file for help panels

    img_main.ipf - main help text file, contains the link to the others
    img_file.ipf - help text file for the File menu items
    img_view.ipf - help text file for the View menu items
    img_help.ipf - help text file for the Help menu
    img_dlg.ipf  - help text file for the File Open dialog

    image16.mak  - 16-bit Image sample NMAKE file
    image16.def  - 16-bit module definition file
    imageS1.mak  - Porting stage 1 NMAKE file
    imageS1.def  - Porting stage 1 module definition file
    image32.mak  - 32-bit Image sample NMAKE file
    image32.def  - 32-bit module definition file

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