4.1 Overview

Plugins that have the capability flag HWPLUG_CAPS_ANIM set will be called whenever Hollywood has to load an animation. The plugin can check then whether the animation file is in a format that the plugin recognizes and if it is, it can open the animation and return the raw pixel data of the individual frames to Hollywood. This makes it possible to load custom animation formats with Hollywood.

By default, anim plugins are automatically activated when Hollywood loads them. Starting with Hollywood 6.0 this behaviour can be changed by setting the HWEXT_ANIM_NOAUTOINIT extension bit. If this bit is set, Hollywood will not automatically activate your plugin at load time. Instead, you will have to manually call hw_AddLoaderAdapter() to activate your plugin. For example, you could call hw_AddLoaderAdapter() from your RequirePlugin() implementation. In that case, the anim plugin would only be activated if the user called @REQUIRE on it. If you do not call hw_AddLoaderAdapter() on a plugin that has auto-initialization disabled, it will only be available if the user addresses it directly through the Loader tag. See Extension plugins to learn how to use plugin extension bits.

Note that anim plugins need not implement all functions offered by the anim plugin API. Some functions are optional and need only be implemented in specific cases. Here's a list of optional functions:

GetFrame()

Only used if you set the HWEXT_ANIM_VECTOR extension flag. See Extension plugins to learn how to use plugin extension bits.

TransformFrame()

Only used if you set the HWEXT_ANIM_VECTOR extension flag. See Extension plugins to learn how to use plugin extension bits.

FreeVectorFrame()

Only used if you set the HWEXT_ANIM_VECTOR extension flag. See Extension plugins to learn how to use plugin extension bits.

GetAnimFormat()

Only used if you set the HWEXT_ANIM_FORMAT extension flag. See Extension plugins to learn how to use plugin extension bits.