When composing hypermedia with interactive image sets the main problem
is to allocate minimal memory of random access memory (RAM). The stan
d-alone product should be accessible to the public and not require too
much memory to maintain interaction between the images and the text.
We designed a new hypermedia application using SuperCard and image sta
cks in PICS format running on a Macintosh LC computer. Memory use was
effective since the images were kept in external files outside the app
lication. On browsing cards the images were requested from the image f
ile and each image was displayed within about 1 second as a floating f
rame on top of the card in the top window. Interactivity when presenti
ng, for example, anatomical parts was achieved by bitmap objects which
were activated through the image by pointing at them through the imag
e. By pointing at a text object the corresponding anatomical bitmap ob
ject was visualised through the image. The stand-alone version of the
application with up to 100 cards runs on a 2 Mb RAM set-up. The maximu
m sizes of the external image stacks are not dependent on the RAM size
.