Cubic QTVR: Hotspot Tutorial v 0.7 - 9/29/00

For the present, adding hotspots to a Cubic movie requires creating seperate images for each face of the pano. These images must be indexed-color bitmaps which use the 8-bit Macintosh System Palette. The indexes in the color table are used as the hotspot numbers. QTVR has always used this system, and in early versions of the software content creators had to do this. Newer software has hidden the fact that the hotspot track is an 8-bit image, but until such software supports cubic movies we'll have to do it the old way. The hotspot tracks always get compressed by the "Graphics" codec, which is 8-bit only. This, combined with the lack of antialiasing results in a very small file size (rarely more than 15k for the whole hotspot track). The following is an attempt to explain it clearly.

One face of a cube

The corresponding hotspots

These instructions are for PhotoShop. It's how I do it. There are two important things to remember: The hotspots must use the Mac System Palette, and they must not be antialiased. Step 1: Open System Palette image. The image below is a gif which uses the Mac System Palette. Since it's an image of the mac system palette, there is no dithering necessary. Save it to you hard disc and open it in PS. You'll be able to eyedropper the colors you need from it.

The Mac 8-bit System Palette

Step 2: Open Cube Faces (or eqirectangular image) Remember that you have to have a hotspot image for every face, even if it's blank. Step 3: Make a New Layer Step 4: Select the Pencil Tool Shortcut: "n" (shift-"n" if the line tool is in front). Open the "Brushes" palette. You'll see that you can select all sorts of big, non-antialiased brushes. Step 5: Grab a Color Hold down the option key to temporarily activate the eyedropper, and pick a color from the System Palette gif. It does not need to be in front. You might want to make a note of the number of the color you picked. PhotoShop 5.5 Tip: When you roll over an indexed color image the index will show up in the info palette, under the rgb values, labeled "idx".

PhotoShop 5.5 Info Palette

Step 6: Paint a Hotspot Go to it. Paint with the pencil. You can fill with the bucket (shortcut: "k"). Step 7: Repeat steps 5 and 6 as necessary. Step 8: Fill with White Grab White (Index 0), switch to the bucket, making sure antialiasing checkbox is off. Fill the area in between the hotspots. Step 9: Save the Hotspot Image Select "Save a Copy" from the file menu, select "pict" from the "Format" popup and save. Step 10: Repeat as necessary

I've run out of time to describe the process of adding these files to a movie. See the "MakeCubicPPC Readme" for some help there. I'll try to do a help file for that, too. I'll improve this when I have time. Feedback is welcome. Note: Adding hotspot names, comments, etc. will require fancier tools than we have at present Another Note: At present, MakeCubicPPC puts hotspot tracks at the end of the file. This means that they download last, and are therefore unavailable until the file is fully downloaded. To remedy this, just run the whole movie through the good old QTVR Flattener. This will move the hotspot track to the beginning of the file, and also give you the option of adding a preview track for the horizontal faces (only).