Home Forums General Game Design Some thoughts about moving on square grids

Viewing 11 posts - 1 through 11 (of 11 total)
  • Author
    Posts
  • #65612
    Phil Dutré
    Participant

    Perhaps nothing new to grid afficionados, but 7 mechanics using on square grids, and how to deal with diagonal movements, explained:

    http://wargaming-mechanics.blogspot.be/2017/06/square-grids.html

     

    • This topic was modified 4 years, 2 months ago by Phil Dutré.
    • This topic was modified 4 years, 2 months ago by Phil Dutré.

    Tiny Tin Men Blog: http://snv-ttm.blogspot.com/
    Wargaming Mechanics Blog: http://wargaming-mechanics.blogspot.com/

    #65633
    John D Salt
    Participant

    A wrinkle I have used in the past violates the usual rule that movement points may not be carried over from one turn to another. With a naval game on a square grid (for reasons of cultural appropriateness, as the WATU wargame that covered the same topic used a tactical table ruled off in 1000 yard squares) I made a diagonal move cost three movement points, and an orthogonal one cost two. My movement allowances were all divisible by six, but need not have been, as I also ruled that any unused movement points at the end of the turn insufficient to move to the next square could be recorded using a “gash die” (in fact you should never need to record more than two, so a gash coin would also work). These were then added to next turn’s movement allowance. I thought it might be a little confusing for players, but in fact they picked it up straight away — although probably they were not a representative selection, most of them having been wargaming for 30+ years at the time.

    All the best,

    John.

    #65646
    Phil Dutré
    Participant

    John,

    do you mind if I add these ideas to the webpost?

    Tiny Tin Men Blog: http://snv-ttm.blogspot.com/
    Wargaming Mechanics Blog: http://wargaming-mechanics.blogspot.com/

    #65647
    Phil Dutré
    Participant

    Tim,

    Offset squares have the same topology has a hexgrid, so the problem of diagonal movement is absent there.

    Tiny Tin Men Blog: http://snv-ttm.blogspot.com/
    Wargaming Mechanics Blog: http://wargaming-mechanics.blogspot.com/

    #65670
    Phil Dutré
    Participant

    It’s not quite the same as hexagons, though. There are some differences, especially radius of x squares looks more lopsided than that of x hexagons.

    Well, yes, you have to shorten the squares by the cosine of 30 degrees (0.87) to preserve the areas. But that has nothing to with the connectivity between adjacent squares.

    There are some other differences as well. A line connecting the centre points of non-adjacent hexagons does not always pass through exactly the corresponding offset squares. Depending on your ruleset, this might or might not be an issue for line of sight calculations.

    • This reply was modified 4 years, 2 months ago by Phil Dutré.

    Tiny Tin Men Blog: http://snv-ttm.blogspot.com/
    Wargaming Mechanics Blog: http://wargaming-mechanics.blogspot.com/

    #65696
    Norm S
    Participant

    Some refer to hexes as providing a ‘zig-zag’ problem, but this is only a visual rather than real thing for ones mind to deal with ….. what it does do to great effect is compress the depth of the battlefield (in one direction against the hex-grain), so for any given size of table, you can have more hexes (therefore locations) going deep. So on a 4 x 3 table you could have a square grid (using 4″squares) of 12 x 9, but if using hexes the zig-zag effect would give a grid 12 hexes wide but an extra two hexes deep (12 x 11). Off-set squares can’t do that, so that is one area that off-set squares and hexes are not equal in effect.

    The shortening of squares as a solution to that creates the same problem as diagonals do, in that distance in any one particular axis will be different to that in another axis. In truth though, I have never really worried about the diagonal thing, it is not a biggie (unless you want to make it so) and the advantages / disadvantages that come with it do at least apply to both players in equal measure.

    A problem that I do have with square grids when only using 4 sides, is that if you want to use a rule in which artillery fires ahead with a fire arc of 3 squares wide (i.e. to include 1 square either side of the gun facing), then that is fine for targets directly ahead ….. until you look at alternate facings from the same square, because once you get 2 squares out, the available fire arcs will develop blind spots from the four facings (square sides) that are available to the artillery – or indeed any ranged weapon.

    #65745
    John D Salt
    Participant

    John,

    do you mind if I add these ideas to the webpost?

    Please go right ahead — as a usual rule, anything I post in a public forum can be re-used freely by anyone.

    Having just checked the rules I was talking about (an early version of my game “The Moon-Grey Sea” on the passage of convoy HX 229) I find that I have misremebered my own writing. In fact I made it 5 movement points to move orthogonally, 7 diagonally. I doubt this would have been worth doing just to get a closer approximation to sqrt(2). However, on the scale of 1000 yards per square, and taking six minutes per game turn (a convenient interval, as I was taught when learning navigation wth the Navy CCF — Admiralty charts and big brass rolling rulers — because in six minutes you travel one cable per knot) this makes one movement point equal to one knot (as a 1000-yard square is five cables across). The “gash die” obviously now needs to be a six-sider. One useful point of this scheme was that it could deal with both destroyers hammering in to the attack at 30 knots, or a U-boat creeping away at 3, without requiring an excessive number of cells in the grid, and having a square grid is, of course, very convenient for keeping track of hidden movement by submarines.

    I seem to recall that SPI’s “Fighting Sail” used a square grid with movement point costs of 2 and 3, but given the proven unreliability of my memory it might be worth checking.

    All the best,

    John.

    #65746
    John D Salt
    Participant

    A problem that I do have with square grids when only using 4 sides, is that if you want to use a rule in which artillery fires ahead with a fire arc of 3 squares wide (i.e. to include 1 square either side of the gun facing), then that is fine for targets directly ahead ….. until you look at alternate facings from the same square, because once you get 2 squares out, the available fire arcs will develop blind spots from the four facings (square sides) that are available to the artillery – or indeed any ranged weapon.

    An analogous problem occurred in Battleline’s game “Submarine!”, which used a hexagonal grid. Submarines could have one of six possible facings, and torpedoes were fired along the hex grain, either directly from the submarine’s hex or one hex either side. The result, of course, was that some hexes were invulnerable to torpedo fire from a submarine in a particular hex well within torpedo range, because no permissible path for the torpedo could possibly be traced. In effect, one could identify pairs of points on the plane between which it was impossible to draw a straight line. This struck me as such an extremely stupid rule that I replaced it immediately with a simple vector system, but unfortunately the game had so many of the other defects common to “Battleline” games that I gave up on it fairly quickly. Strange to say it seems to have been a popular game with lots of people, and I have never seen anyone else comment on its abuse of Euclidean geometry.

    All the best,

    John.

    #65767
    Phil Dutré
    Participant

    Well, yes, you have to shorten the squares by the cosine of 30 degrees (0.87) to preserve the areas.

    Hi Phil, forgive me, but I don’t understand what this means, can you explain?

    You mentioned that a radius of x squares in an off-set grid looks lopsided. If you use squares, that is indeed the case. The reason is that with squares, the distance between two adjacent zig-zag squares is at an angle of 30 degrees with the rectangular grid, and hence is elongated by a factor 1/cosine(30 degrees). That causes a lopsided area. To correct for that, you should not use squares in an off-set grid, but rectangles with size ratio 1:0.87.

    The effect is only visual, gameplay is not affected by this. It’s a similar effect as if you would use rectangles instead of squares in a regular square grid. The game mechanics work still the same, but visually, it looks as if the world is contracted along one dimension.

    • This reply was modified 4 years, 2 months ago by Phil Dutré.

    Tiny Tin Men Blog: http://snv-ttm.blogspot.com/
    Wargaming Mechanics Blog: http://wargaming-mechanics.blogspot.com/

    #80663
    Phil Dutré
    Participant

    I wrote a small follow-up blog, about including Knight’s moves and Camel and Zebra moves, and the difference between a measurement procedure and a counting procedure when moving.

    http://wargaming-mechanics.blogspot.be/2018/01/square-grids-2.html

     

    Tiny Tin Men Blog: http://snv-ttm.blogspot.com/
    Wargaming Mechanics Blog: http://wargaming-mechanics.blogspot.com/

    #81326
    Otto Schmidt
    Participant

    Square grids work fine. I used them for a decade while designing my “Oh God! Anything but a Six!!!” rules. We did this so we could concentrate on sequence, game theory, and streamlining the game. Once I had all that worked out I could go back to free move. But they worked fine as a game. Never went beyond the squares and didn’t trouble about diagonal distances, a square was a square and it was simply range in integers.  By the way Henry Bodenstedt in the 70’s had a square gridded game in the 70’s on the Franco Prussian War.

    Presently, I use squares for naval games. It’s all in the conceptualization. In the game the conceptualization is NOT as a stretch of sea, but a map-table in the admiralty like you see in “Sink the Bismark.”

    Anyway, after we got “Oh God! Anything but a six! perfected we went to a hex grid on the size of Geo-hex, but that was simply for terrain making. We use free movement for the game and it works fine. We like the visuals better.

     

Viewing 11 posts - 1 through 11 (of 11 total)
  • You must be logged in to reply to this topic.