The Apophymator script provides you with a way to produce animation frames based on your Apophysis flames.

In videos, "frames" are the individual images or pictures which are displayed in rapid succession to create an animation or movie.
A special purpose type of frame in the production of video animations is called a "keyframe" (see below).  Since I will be discussing only flame animations I will be using the terms "frame" and "keyframe" essentially to refer simply to the "flames" familiar to all who use Apophysis and/or other flame-oriented applications.
Naturally that relationship between "frames" and "flames" would not be valid when applied to animations that are not composed of flame fractal images.
In flame animations produced with Apophysis, frames and keyframes are nothing more unusual than the individual flames you look at in Apo's Main window or in the galleries at DA.

I wanted to eliminate any potential confusion over those specific terms before I continue.

Flame animations you may have seen on the web tend to use one of two main methods for producing animation frames - or the anims may have been produced with a combination of these methods as in the "Electric Sheep screensaver".

The first main method used to generate the frames for a flame animation is to successively rotate one or more of the triangles which compose a single flame.  That is, only one flame is used as a basis for the entire animation.

To create the frames for this type of animation, a flame's triangles are rotated by a small amount and then the flame is rendered, resulting in one animation frame.  For the next frame the triangles are rotated again, and then this frame is rendered from the parameters resulting from the rotation of the triangles.
The successive rotation of the triangles usually continues until they return to their original positions.
Once the triangles have returned to their original positions, rendering any additional frames would only produce duplications of the frames which have already been rendered.

If you search you will find various scripts available for producing this type of triangle-rotation flame animation with Apophysis.
You can also produce animation frames like these using the flam3 software suite.
Apophymator cannot be used to produce animation frames in this way.

Apophymator uses the second method for animating flames.  Animation frames are generated by proportionally combining the individual parameter values of two flames such that the appearance of the first flame gradually becomes the appearance of the next flame.
In this method, each flame in the original series of flames serves as a "keyframe".  

Using pairs of keyframes from a series of flames, each animation frame is the result of operations that cause all of the values of one keyframe to become the parameter values of the next keyframe (flame).

That process begins at the first keyframe and continues to the second, and then from the second keyframe to the third, and so on until the last keyframe in the original series of flames is reached.

(The process may also be extended back to the first keyframe directly from the last so that the end and start of the animation join together seamlessly.)
Theoretically there is no limit to the number of flames that can be used for keyframes.

The math used for this second method for generating animation frames is called "interpolation".  Each frame's flame parameter values are the result of interpolating the  values of paired keyframe flame parameters.  Each step yields a proportional combination of the paired keyframe parameters values.  So for instance, at the frame that occurs one third of the way between two keyframes, the parameter values for the frame (flame) are the sum of 2/3 times the first keyframe's parameter values plus 1/3 times the second keyframe's parameter values.  That's somewhat oversimplified but it's the main idea.

The Apophymator script uses this interpolation method to generate animation frames from flames you assign as keyframes when you run the script.  Sometimes you may see animations produced in this manner called "morph" or "morphed" animations.

Apophysis itself is not (currently) capable of rendering a series of flames to a video format, and this limitation extends to Apo scripts.
Consequently the Apophymator script only enables you to get half way to a finished (encoded) animation video.  The script will only produce a series of individual flame images, the frames.
Once the frames are generated then third-party software is required to encode the final animation video.
For the time being, I'm not going to try to address the video encoding part of the process.
  
Even so, there are free media viewers or players available which will allow you to watch your rendered individual frame images as though they were an animation without first having to encode those frames into an actual video file.
A couple of examples are Irfanview and Imagen.

You can also use Apophymator to "preview" potential animations before you invest the time to render the frames to their finished size and quality.
But you shouldn't expect a "real time" preview.  Apophymator's animation previews are generally not very "animated" at all. :-/
When you run Apophymator in preview mode every frame must be calculated and rendered "on the fly".
As you might expect this process is considerably slower than viewing an animated video composed from pre-rendered images.

The majority of videos, including animations (but not simple gif animations), are usually encoded so that they will be displayed at about 24 to 30 frames per second (fps).
On my newer core i7 system when I use Apophymator, the preview frame rate - if you can even call it that - is around 1 frame per second when feeding the script keyframe flames composed of only a few transforms.  As with any other flame rendering - all other things being equal - the more complex the flame, the slower the rendering time.  This applies to rendering animation frames too, whether rendering them to a preview window or rendering the images to disk to use later in a video composition.

The main purpose of the preview mode is to help identify any parts of an intended animation that may not be desirable before committing the time to render all of the frames for a finished product.  Well, I like to sit and watch the frames simply because they're flames I haven't seen before.

Although the preview frame rate is very slow, and the preview doesn't look much like an animation at all, I usually don't render animation frames until after I've first run a preview.  I just designate a smaller number of frames between keyframes than I would use in the finished animation.  But I'm getting ahead of myself...

The preview is displayed in the small window explicitly labeled "Preview" in its title bar.  (I also wanted to make that clear since I often see people referring to the Main Apo Window as a "preview").


Well, hmmm.. my intention for this journal entry was to establish some fundamental terms and concepts (as I understand them) that I will employ in future material related to the Apophymator script.
In reality, I believe it's fairly easy to use Apophymator to render animation frames and that it's unnecessary to have any comprehension of just about everything I've written here.

I will move on to how to use the script in my next entry - probably accompanied by some illustrations.