Download HotSpot™ 1.0 (70k)


Important Information About HotSpot™ 1.0


HotSpot™ is a tool with one purpose in mind:

Simplify the task of rebuilding an existing multinode project created in QuickTime VR Authoring Studio™ using reduced sized panorama images to create a much smaller final multinode movie.


The problem that HotSpot™ solves:

On many occasions, we have created multinode panoramas of interesting places and find their size is fine for a hard drive or CD, but is simply not acceptable for Emailing to your mother, or downloading from the web. You may, for example, build a high quality multinode panabout of your favorite national park and include it on a commercial CD. For advertising, you may want to create a low resolution version of this multinode movie and put it on the web for free downloading. The question is, how do you create this low resolution version of your multinode project.


Why this is currently a problem:

QuickTime VR Authoring Studio™ 1.0 matches all panorama hot spot data to the size of your panorama images. Reducing your final stitched panorama images will confuse QuickTime VR Authoring Studio™ and you may lose all of your hot spot and node linking work. The work around to this is to painstakenly recreate all of your hot spots and links...or use HotSpot™ to do it for you.


Hot Spots in QuickTime VR Authoring Studio™ 1.0:

When you create a multinode project in QuickTime VR Authoring Studio™, it creates a hot spot file called (as a default name) "<scene name>.hot". This file contains definitions for all of the hot spots used in the scene creator. Each project can have multiple scenes and you will have one hot spot file per scene created.


What HotSpot™ does:

HotSpot™ takes as user input the original image size and the new image size of your panoramas. The horizontal and vertical ratios are then calculated for use in hot spot data resizing. HotSpot™ brings up a standard file dialog and asks for a hot spot file to munge (be sure you have a copy of the original hot spot file saved away). HotSpot™ verifies that it understands all of the panorama hot spot data in the file and, if all is well, it modifies the hot spot data directly in the file to fit the new image size. You are now free to open up your project and create a mini version of your original work.


There Are Some Rules:

1. Despite the look of the user interface, HotSpot™ can correctly deal with multinode projects that consist of partial panoramas and panoramas of mixed image size. The one catch is that all panorama images must be reduced by the same percentage. HotSpot™ uses a reduction ratio calculated from the user input for all hot spots, so it is important that all images have been reduced by the same amount.

2. HotSpot™ can deal with projects that have objects hot spots since this data is simply ignored. If you change the size of your object movies you will need to resize your object hot spots by hand in the scene editor. A future version of HotSpot™ may be able to handle hot spots for resized object images.

3. You must move your original final multinode movie, all individual tile movies, and all individual panorama movies from their original locations before rebuilding the project. We suggest the you put them in a folder called "Full Size Data" or some such. Not doing this will confuse QuickTime VR Authoring Studio's internal view of the size of the world and you will not be able to create anything, causing your machine to explode and forcing the moon out of its orbit. This is serious. Move those files elsewhere.

4. It is important that you put a copy of your original hot spot file in a safe place (the "Full Size Data" folder or some such) since HotSpot™ will change the data in the project's hot spot file directly.

5. HotSpot™ 1.0 currently only operates on hot spot files created with QuickTime VR Authoring Studio™ 1.0. A future version of QuickTime VR Authoring Studio™ may use different hot spot data structures which will render HotSpot™ useless.

6. Legal Stuff: HotSpot™ is not guaranteed to do anything useful at all and may corrupt important files if used. If the data corruption caused by HotSpot™ appears to be useful by allowing you to create smaller multinode panoramas, be aware this is only a coincidence and may not happen again. Do not use HotSpot™ on the only copy of a hot spot file as the original data will be destroyed. Back up your hot spot files before running HotSpot™.

7. Did we mention that you should make a back up of your original hot spot file?



Important note on changing your panorama image size:

QuickTime VR Authoring Studio™ likes to make your vertical tile size either 12 or 24, so you must be sure your resized images conform to the tile size restrictions imposed by these values. If you are unfamiliar with the tile size rules, they go like this:

The width and height of the tile must be evenly divisible by 4 since all tiles must be 4 byte aligned.The height of the panorama image must be divisible by the vertical tile size (12 or 24) AND the extra factor of 4 as noted above. This means that your panorama height must be evenly divisible by 48 (12*4) or 96 (24*4). If you are using a different tile size within your QuickTime VR Authoring Studio™ project, you will need to be sure your panorama image height is evenly divisible by: (your tile size) * 4. The width of your panoramas must also conform to this rule. The width must be evenly divisible by the the number of horizontal tiles and the extra factor of 4. The horizontal tile size is usually set to 1 so your panorama width must simply be divisible by 4.

So the rule:

  • The height of your panorama must be evenly divisible by (vertical tile size * 4).
  • The width of your panorama must be evenly divisible by (horizontal tile size * 4).
  • The vertical tile size is generally 12 or 24 so the height of your panorama must be evenly divisible by 48 or 96.
  • The horizontal tile size is generally 1 so the width of your panorama must be evenly divisible by 4.


How to calculate a correct new panorama image size:

We will assume our original panorama image size is 4320 x 820 and that we want to reduce our image to 30% (0.30) of original size. We are using a vertical tile size of 24 and a horizontal tile size of 1. We therefore need to make our panorama image divisible by 96 in its height and 4 in its width. We will always round our values down to the nearest integer value in this example, you could round up if you wanted. You simply need an integer tile rule multiple to get correct image sizes.


To determine the appropriate height and width for the reduced panorama, follow these steps:
1. Reduce the panorama height of 4320 to 30% of its size.
--> 4320 * 0.30 = 1296
2. Divide the reduced height of 1296 by 96 to get the closest vertical tile size multiple allowed.
--> 1296 / 96 = 13.5
3. Multiply the rounded multiple of 13 by our tile size multiplier of 96 (tile size multiplied by the extra factor of 4 to get 96) to get the actual allowed vertical image size.
--> 13 * 96 = 1248
4. Resize the panorama image to a vertical height of 1248 to get the correct height that can be diced.

5. Reduce the panorama width of 820 to 30% of its size.

--> 820 * 0.30 = 246
6. Divide the reduced width of 246 by 4 to get the closest horizontal tile size multiple allowed.
--> 246 / 4 = 61.5
7. Multiply the rounded multiple of 61 by our tile size multiplier of 4 to get the actual allowed horizontal image size.
--> 61 * 4 = 244
8. Resize the panorama image to a horizontal width of 244 to get the correct width that can be diced.

The final reduced image size is 1248 x 244. Be sure to sharpen the image after it has been reduced to get back some of the detail that may be lost in the reduction process.



Who Created HotSpot™:

HotSpot™ was created by Quinn for Concepts In Motion to work with Apple's QuickTime VR Authoring Studio™. Quinn can be reached at You should visit for a bunch of QTVR authoring information, QTVR lessons, tips, techniques and QTVR programming examples.


HotSpot™ is Freeware. You may use it at no cost. However, HotSpot™ is still Copyright © 1998 by Concepts In Motion. All rights reserved. HotSpot™ may not be included in any for-profit software compilation or bundled with any other for-profit package, except with prior written consent from the author, Quinn. HotSpot™ may be distributed freely on on-line services and by users groups, except where noted above, provided it is distributed unmodified along with this text file.

© 1998 Concepts In Motion, Inc. All rights reserved.

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