Panoviewer Readme

This project shows the use of many interactive QT features, such as
QTVR, Wired Sprites, Movie Media tracks, qtlists, and more. It
demonstrates the use of the New Sprite Track Image command, new to QT
6.0, and shows how one might use wired actions and sprites to design a
controller which not only looks different from the default QTVR
controller, but works differently as well.

For an on-line example paste the following URL into QTPlayer's "Open
URL" dialog: http://www.blanpied.net/workshop/vr/japan/panoviewer.mov

How the movie works:

The movie itself is less than 90k, and includes only the background, the
skin, the controls, and some placeholder art.

As soon as it loads, the "thumbs" sprite track loads a qtlist by the
name of "movies.xml" which just contains a list of movie names:

<movielist>
	<movie>blossoms02</movie>
	<movie>FishMarket</movie>
	<movie>Gokufuji</movie>
	<movie>Kabukiza</movie> 
	<movie>ueno</movie>
</movielist>

Note that there are no ".mov" extensions on these names. Those will get
added later, when they're needed. See the "FrameLoaded" handler on the
sprite "list loader" in the first sample. When the xml is loaded QT
creates a qtlist for the movie.

Then in the second sample of the "thumbs" sprite track the "thumb
loader" sprite loads each of the thumbs by getting the names from the
qtlist and tacking the string ".jpg", resulting in relative URLs for the
Sprite Track New Image call (LoadNewImage in LSP's QScript).

This is done in an idle handler to space out the loads and image
assignments a bit in time. Note that the sprite track's idle rate has
been set to 60, which means the handler gets called once a second.

Once a new image is loaded, the appropriate thumbnail sprite get's it's
image index assigned to the new image, replacing the placeholder which
was there at launch.

Once the thumbnail images have been loaded and placed on the sprites the
"thumb loader" sprite is disposed of to get rid of the idle handler, and
playback moves to the "playing" part of the movie.

When a thumb is clicked on it checks the qtlist, looking for the element
with the index which corresponds to the ID of the clicked-on sprite.
This element contains the movie name, which gets ".mov" tacked on,
resulting in a relative URL which can be used to load the movie into the
Movie track.

The panning and zooming controls are handled in their own sprite track,
and are much simpler than the movie and thumb loading stuff.

Once this is all set up, all that needs to be done to change the movies
and thumbs is to put the new assets in the folder with the movie and
change the names in the xml file.

Other tracks in the project include a text track which is used for
debugging and a skin "FastTrack". There are various places in the
scripts where debugging information is sent to the text track. During
development one leaves the text track in some visible location, and then
for released versions it can be hidden or deleted. I find it useful to
keep it around, in case I find the need to modify the project later.
It's probably a good idea to comment out the actions which send text to
it, but for this project they are left on.

The Skin "Fast Track" is a new LiveStage construct introduced by
TotallyHip in version 4 of the product. It makes it easy to slap the
background and skin tracks together. I haven't used it to it's full
potential.

For more info check out the comments in the various scripts. The sprite
tracks ("thumbs" and "controls") do all the work.

To test the project you'll need some movies (any kind, but named with
".mov" at the end), thumbs (101x61 pixel images, named the same as the
movies, but with ".jpg"), and an updated xml file containing the base
filenames (no dot or extension).


Copyright 2002 Eric Blanpied

- Eric Blanpied,  Oct 2002.