AWeb GIF plugin

General

The awebgif plugin for AWeb allows you to view all GIF images. Features include:

Optional progressive display of loading images
Optional playback of animated GIFs
Support for transparent images
Support for scaling
Support for CyberGraphics

Installation

Follow these steps to install the AWeb GIF plugin.

Run the supplied Installer script. It will copy the necessary files to a drawer awebplugins in the drawer where the AWeb-II program is located.
Run the .

Manual Installation

If, for some reason, you don't want to install the plugin automatically, you can install it by hand.

Copy the file named awebgif.awebplugin to a location of your choice. The recommended location for plugins like this is a drawer awebplugins in the drawer where the AWeb-II program is located.
Start AWeb-II, open the browser settings and bring up the Viewers page. Select the entry for MIME type IMAGE/GIF and change the following settings:
- Action: "AWeb Plugin (A)"
- Name: the location where you copied the file awebgif.awebplugin
- Arguments: leave blank or supply optional parameters, see below
Don't forget to save your settings.

Parameters

The awebgif plugin supports two optional parameters. You can type the chosen parameters in the "Arguments:" field of the settings window. Separate the parameters by a comma or space, if you specify more than one.

PROGRESS=0|number

Specifies the number of image scan lines to decode before the display is updated. A higher number is faster but results in chunkier building of the image. PROGRESS=1 gives the smoothest progressive display but is relatively slow. The default value is 4, which is a good compromise between speed and visual attractiveness.

If you specify PROGRESS=0, progressive display is disabled. The image is not displayed until decoding is ready.

LOOPS=-1|0|number

Specifies how many times animations should be played back. The animation playback will stop when the specified number of cycles has been played. Default is -1, which means playback an infinite number of times.

If you specify LOOPS=0, animations are not played back. Second and later animation frames are not even decoded. This saves CPU speed and memory (precious chip memory on non-CyberGraphics systems).

LOWPRI

The LOWPRI argument will run the decoder at a lower priority than default. If you are using your Amiga for other tasks while AWeb is downloading images, this feature helps you to keep the GUI responsive when many images are being decoded. However, if you are running CPU intensive tasks this argument could stop images from being processed alltogether.

Note that the LOWPRI argument might not be effective when you use a custom task scheduler like Executive. Use task name "AWebGif decoder" to configure the decoder task in custom schedulers.

Commands

AWeb version 3.3 or higher supports plugin commands. This plugin features three commands:
(upper or lower case doesn't matter)

STOPANIM: Immediately stops all current and future animations.
STARTANIM: Restarts all animations after they were stopped earlier with the STOPANIM command.
ANIM: Returns the animation state: "0" if animations are stopped, "1" otherwise.

Example of usage:
In the AWeb GUI settings requester, assign the following command to a key, to a button or to a popup menu item:

   PLUGIN "awebgif.awebplugin" "StopAnim"

to stop animations.
Likewise, the command:

   PLUGIN "awebgif.awebplugin" "StartAnim"

will restart animations.

Support

The AWeb GIF plugin was written by the author of AWeb-II. Any questions, comments or bug reports can be addressed to Yvon Rozijn <yrozijn@xs4all.nl>.

Disclaimer

This software is provided "as is". No warranties are made, either expressed or implied, with respect to reliability, quality, performance, or operation of this software. The use of this program is at your own risk. Yvon Rozijn assumes no responsibility or liability for any damage or losses resulting from the use of this software, even if advised of the possibility of such damage or loss.

Copyright

History

awebgif.awebplugin 1.8 (5-9-1999)

Cleaned up the code a bit.

awebgif.awebplugin 1.7 (1-5-1999)

No longer uses chip memory if CyberGraphics is used.
Added commands to start and stop animations.
Now respects the maximum number of iterations specified in the image file.

awebgif.awebplugin 1.6 (19-10-1998)

Added support for proportional scaling (only one of WIDTH and HEIGHT specified).
Added LOOPS argument to replace ANIMATE.
Fixed bug in decoder that caused some images to be rejected.

awebgif.awebplugin 1.4 (01-03-1998)

Added LOWPRI argument.

awebgif.awebplugin 1.3 (25-02-1998)

Removed possible decoder stalls.
Much faster progressive display of scaled images.

awebgif.awebplugin 1.2 (14-02-1998)

Now image doesn't animate when it's used as background.
Sometimes animation didn't play after decoding.
Crashed with very small interlaced GIF images.
Crashed on animated GIF with delay time zero for all frames.
Spurious rendering (causing flicker) when clicked on a map or when bringing up the popup menu.

awebgif.awebplugin 1.1 (09-02-1998)

Animation was stopped at frame with delay zero.
Now animation stops when no AWeb window is active.
Disposal method "restore background" was applied to the image frame itself instead of the working copy.
If frame was transparent but previous wasn't, the mask plane was generated incorrectly.
Fixed enforcer hits when changing screen mode.

awebgif.awebplugin 1.0 (04-02-1998)

Initial version