How can I make an area passable to the player?

[I Must Be Crazy 2]

I'm sure that FO2 veterans out there have experienced how the player character can sometimes walk on tables (Den?), walk directly into a bookshelf (Den, too?), or walk through certain solid-looking walls (like in the Hubologist Base in San Fran (now this one I know for sure )) or heck, even the mine wall to get to Chuck Stodgers in Broken Hills while I'm at it

I am thinking that there is a certain bit or an object value that is making the map behave that way. I have a couple of questions:

1. Am I correct in assuming that a single variable or bit is responsible for making a particular hex on a given map passable to the player?

2. If I am correct in that assumption, then what Watcom or F2 compiler scripting command can I use to set that variable to make the hex passable to the player without affecting the current graphic already existing in that hex? (Imagine that for some crazy reason, I wanted to write a script in kcdunton.ssl (Duntons' script) that would, on starting any conversation with the Duntons, re-define the map to make it possible for the player to walk straight through the back wall of the Golden Gecko tavern without making a hole appear in that wall, what would I do?)

3. What is the formula for calculating the coordinates of a particular hex on a map?

 

[jargo]

Am I correct in assuming that a single variable or bit is responsible for making a particular hex on a given map passable to the player?

Well not a variable but object flag and it can be set to make that object passable(like wall or table).
But you just can't do that from script, only set in mapper.

If I am correct in that assumption, then what Watcom or F2 compiler scripting command can I use to set that variable to make the hex passable to the player without affecting the current graphic already existing in that hex? (Imagine that for some crazy reason, I wanted to write a script in kcdunton.ssl (Duntons' script) that would, on starting any conversation with the Duntons, re-define the map to make it possible for the player to walk straight through the back wall of the Golden Gecko tavern without making a hole appear in that wall, what would I do?)

It can be done, you have to make a new wall that looks just like that one in Den but with NOBLOCK flag set to NO.
Then in script you have to destroy this old wall and replace it with your new passable wall.

What is the formula for calculating the coordinates of a particular hex on a map?

Why You want to calculate that just read it from mapper.
If you want X and Y coordinates from tile number then it goes like that:

X = tile_num mod 200
Y = tile_num div 200

Or just paste tile number to FSE and select it with mouse