Quark Robot dev blog

LR2 Update #6

Gareth -

This Lode Runner 2 update contains mostly info about file types. 'Oh, that's not very interesting', you're thinking to yourselves! Fear not, there's a few other bits and pieces that may (or may not) change that sentiment!

Editor

  • camera is now set correctly when loading levels that don't have the camera locked
  • the active brick draws semi-transparent to assist painting
  • holding SHIFT and moving the mouse around will now highlight the brick under the cursor and snap to it - handy to pick a brick that's hiding (new)
  • unlike the original, SHIFT+LEFT-CLICK does not snap the cursor to the brick
  • added SHIFT+RIGHT-CLICK to eye drop the brick (new) & scroll to it in the brick window (new)
  • the brick window now highlights the active brick (new)
  • basic painting & deleting added (including shadows)
  • basic decoding of the RDT file type (more on that below)
  • basic decoding of the MLT file type (more on that below)
  • nav icon updates based on blastability & passability (still rough as I don't fully understand the values yet)


Paint helper


I see you!

Shadows

The original editor saves if a volume has a shadow being cast on to it. This is a massive help as it means we only need to do a simple check when painting or deleting bricks, rather than checking the entire level.

There are 2 shadow masks, both stored in GOG.PRX, used to create the shadows & other effects (that are possibly the rip-through effect when a player runs behind a brick).


Shadow masks


Mystery masks

The manual states:

The maximum height from which a shadow can be cast is fourteen Z planes.

If a brick rests above another brick by two Z planes or more, it will cast a shadow directly below.

Generally speaking, only bricks which appear to be a cube, or diggable, cast a shadow.

When painting a brick, we need to search above 14 planes to determine if there's a brick there. If so, apply the shadow that's listed in the asset's RDT entry. Repeat this step searching downwards.

To delete, simply search above & below. If (below.z - above.z) is within range, then apply above's shadow to below. If nothing above, remove below's shadow.


HOH casting shadows below

RDT files

Each world has a RDT file (R something Template?) that stores the following about each paintable asset:

  • if it's blastable/destructable
  • passability
  • shadow type that gets cast (this is the 0-based index of a mask in the above shadow mask image)
  • more that I haven't worked out yet

I use the excellent Hex Workshop to analyse files and figure out how they work.

MLT files

Each world PRX contains several MLT file types (MuLti Temlpate?), these are used to build up the multi-volume templates in the editor.

All files start with the same 12 bytes:
16 1C 7E DE 00 00 03 00 00 00 05 00

This is followed by 2 bytes that indicate the amount of resources the volume is made up of:
04 00

So far, that's all I've looked into here...

Anyone?

You’ve been reading for awhile, haven’t you? Well, you deserve a reward. Mention this text in an e-mail to loderunner@presage.com and you will get a free level.

That's from the original editor manual... did anyone actually email and get it? If so, I'd be interested in taking a look.