SCUMM/Technical Reference/Object resources
In v6 objects are split in 2 chunks: OBIM and OBCD. OBIM store the images, zplanes, etc, while OBCD mostly store the scripts.
- IMHD : header
- IMnn : images
- SMAP (or BMOP)
Note: In IMnn and ZPnn nn represent an hexadecimal number.
obj id : 16le num imnn : 16le num zpnn : 16le (per IMnn block) flags : 8 unknown : 8 x : 16le y : 16le width : 16le height : 16le num hotspots : 16le (usually one for each IMnn, but their is one even if no IMnn is present) hotspots x : 16le signed y : 16le signed
The hotspots indicate where the actors should stand when they walk to the object.
Each IMnn contain an image for a state. As state 0 display nothing they start at 01. IMnn chunks contain a SMAP or BMOP chunk enventually followed by some ZPnn blocks. See Image resources for more details on these.
- CDHD : header
- VERB : script
- OBNA : name
obj id : 16le x : 16le y : 16le width : 16le height : 16le flags : 8 parent : 8 walk_x : 16le signed walk_y : 16le signed actor dir : 8 (direction the actor will look at when standing in front of the object)
Note that the size and position must match those in the IMHD.
The VERB chunk hold the scripts. It start with a table giving the offset of the entry point for each verb handled by the object code, followed by the code.
offset table : vlc verb : 8 (0xFF is default) offset : 16le table end : 8 (must be 0) code
The OBNA chunk simply contain a null terminated string.
V5 objects are a lot like V6 Objects, with minor differences.
obj id : 16le num imnn : 16le num zpnn : 16le (per IMnn block) flags : 8 unknown : 8 x : 16le y : 16le width : 16le height : 16le
IMHD omits the hotspots.
obj id : 16le x : 8 y : 8 width : 8 height : 8 flags : 8 parent : 8 walk_x : 16le signed walk_y : 16le signed actor dir : 8 (direction the actor will look at when standing in front of the object)
x, y, width, and height are bytes. Their values should be multiplied by 8 (the size of an image strip).
In v4 objects are split in 2 chunks: OI and OC. OC does not have any sub-blocks like v5 or v6 objects; it contains all header information and the SCUMM script.
obj id : 16le unknown : 8 x : 8 y, parent state : 8 (parent state is AND 0x80, y is AND 0x7F) width : 8 parent : 8 walk_x : 16le signed(?) walk_y : 16le signed(?) height, actor dir : 8 (height is AND 0xF8, actor dir is AND 0x07) name offset : 8 (point to location of object name, from start of OC block) verb table : variable object name : variable, null-terminated string SCUMM script : variable
The verb table is made up of multiple entries, each looks like this:
verb ID : 8 offset : 16le (from start of script?)
The number of entries will vary depending on the interactions defined for the object.