Invalid Tiles

[Noivilbo]

I am trying to make a collection of all the invalid tiles, but I don't know where to get them all. Is there already a place with all of them? Is there a page on the wiki about them?

[pillowpc2001]

Do you mean single tiles that are invalid, or top/bottom layer tile combinations? If it's the latter, then that would be any buried tile that isn't buried under Chip, a monster or a block. If it's the former, then I'm not really sure if there are any anymore - I think Tile World's Lynx mode can now handle the "old" invalid tiles - "combinatiion" tile, NOT USED tiles, Exit 2 through 4 tiles, Chip Swim tiles, and the Chip Death tiles. I think they are now treated as walls - or at least most of them are, maybe not all of them.

[Noivilbo]

I mean the AND/OR tiles. Where can I find those? The 00 Tile too.

[jblewis]

Actually, in Tile World Lynx, making Chip touch a Swimming Chip tile kills him as fire or water would - this doesn't work when monsters or blocks touch the Swimming Chip, like it would in MS.

[geochip]

The only easy way to do it is to open Chipedit.ini while Chipedit isn't opened and change PIECE to 112. You'll be able to place in the Bug N one. If you change it to say, 113, you will be able place in a Bug W in the map. However, when you play the level, they will appear as Bug N.

HOWEVER, using data reset, you can create these tiles, but only appear in the top right corner, buried, when the button is press. Since all the tiles go up to 207, level 208 (and up) seem to contain the combination tile.

Here's an example: http://www.freewebs.com/geochip/dataresetandinvalidtiles.ccl

[pillowpc2001]

What are the AND/OR tiles?

[Noivilbo]

I'm not sure what they do, but the OR tiles have the white background, and the OR tiles have the black.

They act as walls.

That's all I know.

[Tom P]

For some reason Mapmaker never puts the invalid tiles on the screenshot so I'm forced to somehow change the invalid tiles with my own by copying and pasting from image. Yeah, it would be useful to have the full set as well for ease of use.

[pillowpc2001]

Oh, so the AND/OR tiles are the same as the 00 FLOOR-type tiles...

[Icy001]

I've been playing with this for a while, and here's what I've come up with.

Tiles:
Chip's Challenge stores tiles internally as two-byte numbers. Therefore tiles go from 0 to 255. For example, Tile 0 is floor, Tile 1 is wall, etc.

The normal tiles occupy positions 0 through 111. The OR tiles are copies of the transparent tiles only (with a white background), and there are 48 of them. Therefore the OR tiles occupy positions 112 through 159. The AND tiles are the same as OR except that the white background is turned to black and any non-background pixel is now white. These occupy positions 160-207.

Theoretically, tiles from 208-255 exist. However, Chip's Challenge does not draw these tiles. In fact, when such a tile appears on the window, the program does not even blank it out or draw on it. It just appears as whatever was on that square before.

Data reset
First, it is important to know that (x, 32) acts as the "bottom layer" of the bottom layer of (x, 0).
When Chip successfully clones (x, 32), three things happen:

1. The "Clone Block N" from the bottom layer of (x, 0) "clones" itself to (x, 31).
2. The 16-bit value from (x, 32) gets "moved up" to the bottom layer of (x, 0).
3. That value from (x, 32) is set to 0.

The important part about resetting the level number
Each tile stores a two-byte number. However, the level number is stored as four bytes, so what to do? The solution is simple: Store the two lower-order bytes in (0, 32) and the two higher-order bytes in (1, 32).

For levels below 256, such as 77, the two bytes at (1, 32) are obviously 0, since there is enough space to simply store it at (0, 32). In hex, this would be 4D. When (0, 32) is reset, the level number goes down to 0.

However, things get interesting for levels 256 and above. For a level such as 300, which is 12C in hex, the two lower-order bytes are 2C, and the two higher-order bytes are 01. Therefore, (0, 32) will contain 2C and (1, 32) will contain 01. When (0, 32) is reset, the level number is now 100 in hex, so it will go to 256 instead of 0! (You can try this for yourself.)

Now, try resetting (1, 32). It should bring you to the level number whose hex representation is 2C, since the "1" in front was erased. This is level 44. Interesting!

This post has been edited by Icy001 on Aug 12 2009, 12:55 AM