Myst VIEW resources

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Myst
Mohawk Overview
CLRC EXIT HINT INIT
MJMP MSND PICT RLST
VIEW WDIB HELP RSFL
Scripts Variables

VIEW resources are the candidate Myst card representations, as they glue other resources together. In particular they seem to describe what to show on screen, what sound to play and where to find additional data about the card.

Original hints by Petroff Heroj.

Basic Format

The data is split into five sections with variable size and different meanings:

  • card flags
  • pictures
  • sounds
  • element list
  • other resources

Card flags

This is just

unsigned short card_flags

card_flags seems either 0 or 1. It's 0 for regular cards, while 1 is suspected to disable game saving in that card.

Picture section

This section defines the card background picture, which may be static or dependent on the values of variables. The section starts with

unsigned short count

If count = 0 then there is a single, static background picture and the whole section reduces to

unsigned short count = 0
unsigned short picture_id

where picture_id is the WDIB (or PICT) resource ID.

Otherwise, if count > 0, the section contains count conditional blocks:

unsigned short count
variable conditional blocks

Each conditional block associates a variable with an array of picture IDs:

unsigned short variable
unsigned short id_count
short picture_ids[id_count]

The card will use the value of the specified variable to index the ID array and display that picture.

Sound section

This section specifies ambient sounds for the card. It uses a basic "command" mechanism to continue with the already playing sound, alter it or start a different one.

short sound

If sound is -1 or -3, the section stops here.

  • -1 seems to continue with the current sound.
  • -3 seems to stop the current sound at all (mute).

If sound is not negative or -2, the section includes a second field:

short sound
unsigned short volume

A positive sound stops the currently running sound and starts the given one, while -2 seems to continue with the currently running sound, but different volume.

Finally, if sound is -4, there is a conditional block similar to those in the picture section:

short sound = -4
unsigned short variable
unsigned short count
variable sound specifications

Each sound specification is a single short, followed by a second one if it's not negative or -2, similarly to what happens for the first field of the section. This probably chooses the sound/flags combination based on the given variable.

Element list

This section seems to list elements (pictures, sounds) available to the card. It is suspected that those elements can then be activated by scripts.

unsigned short count
variable element specifications

Each specification begins with an unsigned short type describing what the element is.

  • Type 1 is a picture (WDIB or PICT). Resource ID follows.
  • Type 2 is a sound (MSND). Resource ID follows.
  • Type 3 is a conditional block associating a variable with an ID array. This structure follows:
unsigned short variable
unsigned short id_count
unsigned short u0
short ids[id_count]

The variable value is used to index the ID array. IDs can be -1, probably meaning that nothing should be done in that case.

  • Type 4 seems to refer to pictures, since a WDIB ID follows.
  • Type 5 seems to refer to sounds, since a MSND ID follows.

Other resources

The final section points to associated resources that further describe the card, namely RLST, HINT, INIT and EXIT:

unsigned short rlst_id
unsigned short hint_id
unsigned short init_id
unsigned short exit_id

These values can be zero, indicating that the corresponding resource does not exist (i.e. a card might not have an associated HINT). It happens that all the IDs match the VIEW ID when they are not zero. Furthermore, rlst_id is always set: no cards exist without hotspot descriptions.