Re: HEX maps how?

From: gdunbar@us.oracle.com

Date: Wed, 14 Jun 1995 00:00:00 +0000

In <165931481wnr@antsnest.demon.co.uk>, Tim Lomas <tim@antsnest.demon.co.uk> writes:
>In article: <3rh32i$nsq@io.salford.ac.uk>  Jason Wroe <scjwroe@scot1.ucsalf.ac.uk> writes:
>
>> I need an algorythm for printing and displaying a Hex style mapping system,
>> source should also be able to move say a person from one coordinate to the
>> other how would you go about this?
>
>The first thing to consider is that there are 4 different types of Hex maps, odd and even grain and odd and even indent.
>
>Then you can use the sort of thing below
>
>x & y is the location of the hex you're starting from, x1 & y1 are the co-ordinates you finish at, dir is the direction, 1-6, 1 being N or NE depending on
>the orientation and carrying on clockwise.
>
>The edge_hex function calkl checks to make sure you're not at one edge of the map (in which case you can't move.
>
>The orientation variable refers to grain & indent, I forget which is which off hand but you can figure that out.
>
>Just in case you're wondering it does work <G>. I grabbed a section of source code from STGMap.  It's written in Borland Pascal v7
>
>Procedure Next_loc(x,y : word; var x1,y1 : word; dir :byte);

Here's some (much shorter) C code to handle the case:

0,0     2,0
    1,0     3,0
0,1     2,1
    1,1     3,1
0,2     2,2

/* This code is completely untested, and in no way guaranteed
to work. I think it does though.

Also, the modula operators make the world wrap around; if you
don't want that to happen, you'll need to check for boundaries
and return some sort of error if they try to move that
direction */

int xsize,ysize;

#define odd(num) ((num)%2)
#define even(num) ((num+1)%2)

void Next_loc(int x, int y, int *x1, int *y1, int dir) {
  switch (dir) {
  case 0: /* north */
    *y1 = (y - 1) % ysize;
    *x1 = x;
    break;
  case 1: /* northeast */
    *y1 = (y - (even(x))) % ysize;
    *x1 = (x + 1) % xsize;
    break;
  case 2: /* southeast */
    *y1 = (y + (odd(x))) % ysize;
    *x1 = (x + 1) % xsize;
    break;
  case 3: /* south */
    *y1 = (y + 1) % ysize;
    *x1 = x;
    break;
  case 4: /* southwest */
    *y1 = (y + (odd(x))) % ysize;
    *x1 = (x - 1) % xsize;
    break;
  case 5: /* northwest */
    *y1 = (y - (even(x))) % ysize;
    *x1 = (x - 1) % xsize;
    break;
  default:
    /* what direction is this? */
    x1 = x;
    y1 = y;
  }
}

Geoff

References

HEX maps how?
Jason Wroe <scjwroe@scot1.ucsalf.ac.uk>
Mon, 12 Jun 1995 00:00:00 +0000
Re: HEX maps how?
Tim Lomas <tim@antsnest.demon.co.uk>
Tue, 13 Jun 1995 00:00:00 +0000

Referenced By

HEX maps how?
Jason Wroe <scjwroe@scot1.ucsalf.ac.uk>
Mon, 12 Jun 1995 00:00:00 +0000
Re: HEX maps how?
Tim Lomas <tim@antsnest.demon.co.uk>
Tue, 13 Jun 1995 00:00:00 +0000