Short: Virtual Screen GIF viewer (CLI) Architecture: m68k-amigaos **************************************************************************** * VirtGIF version 1.0 - Virtual Screen GIF Viewer * * Copyright (c) 1989, by Patrick J. Maloney * * Compuserve ID: [73407,3676] * **************************************************************************** * GIF and 'Graphics Interchange Format' are trademarks (tm) of * * Compuserve, Inc., an H&R Block Company. * **************************************************************************** VirtGIF is freely redistributable. This means you can give it to anyone you like. It is NOT, however, intended for commercial sale, and copyright is retained by me. This documentation file MUST be distributed with VirtGIF. **************************************************************************** VirtGIF version 1.0 - User Notes - 08/08/89 ------------------------------------------- VirtGIF is a program, runable only from the CLI, which will COMPLETELY display any GIF picture, using HAM mode for pics with > 32 colors. Any picture that will not fit on the screen, i.e. bigger than 640 x 400 with <= 16 colors or bigger than 320 x 200 with > 16 colors will have only a portion of it displayed, with the user having the ability to scroll around and view the rest of the picture. Play around with different GIF files to get a feel of how it handles different colors/resolution. Example: 640 x 480 w/256 colors will be displayed on a 320 x 200 HAM screen with the ability to scroll around and see the entire picture. To run VirtGIF, type: 1>VirtGIF gif-file.GIF Giving a non-gif, non-existent, or no file will cause an appropriate message to be displayed. Once a file is determined to be a valid GIF file, various information is displayed in the CLI window from which it is run. Number of rows left to process will be displayed until it is finished. Press the RIGHT mouse button at any time to abort. (NOTE: The screen/window is opened in the background, and is the ACTIVE screen/window upon opening. This window/ screen MUST be the ACTIVE screen for the abort function to work.) Once the screen is processed, CLICK in the CLI window you ran VirtGIF in and then press to pop screen to front and view the picture. If scrolling is enabled, PRESS & HOLD the LEFT mouse button and move the pointer to scroll the picture in all directions. (NOTE: If the pointer reaches the edge of the screen, you will have to release the LEFT mouse button, move pointer to center of screen, then PRESS/HOLD/move again since if the pointer does not move, the program cannot detect relative positioning to scroll.) Press RIGHT mouse button to exit program. Additional notes: 1. Due to the nature of HAM mode, HAM pictures which scroll will have strange color changes on the leftmost part of the screen, and possibly in whole areas of a single color. However, for most pictures, this should be a minor problem. A work-around is in the works for this. 2. This program has been tested up to a resolution of 1024 x 768 with 16 colors, but this requires that you have at least 430K of CHIP RAM free, which is cutting it close. Try it and see if it will work for you. 3. This program can be slow at times, so be patient when decoding large pictures. 4. Runs fine with expansion memory. ---------------------------------------------------------------------------- Additions for future versions: - Faster decoding. - Display information which is currently in CLI on a window of the VirtGIF screen - View multiple files - Save displayed portion (when scrolling) as IFF. - Eliminate annoying color distortions on left border of screen in HAM mode - Allow user to force different resultion/scroll (i.e., display 640 x 400 pics with <=16 colors on 320 x 200 screen with scrolling) - Allow user to select optional "smoothing" algorithm for better color representation in HAM mode - Any others you suggest... ALL comments(positive/negative) and suggestions are welcome! I can be reached on CompuServe by using my account number: --> Patrick Maloney [73407,3676]