WML Utilities

Determining opposite coordinates

Obsolete? the Standard Location Filter now supports directions, which might be able to replace any uses of this utility.

# Using this, you can determine the coordinates on the "opposite side" of a
# central hex, relative to another hex adjacent to it. What this really means
# is illustrated below:
#       __            __            __
#    __/  \__      __/2 \__      __/  \__
#   /  \__/1 \    /  \__/  \    /2 \__/  \    C: central point
#   \__/C \__/    \__/C \__/    \__/C \__/    1: the hex to "mirror"
#   /2 \__/  \    /  \__/  \    /  \__/1 \    2: the result
#   \__/  \__/    \__/1 \__/    \__/  \__/
#      \__/          \__/          \__/
#
# The coordinates of the central point are given in {CENTER_X} and {CENTER_Y},
# and the coordinates of hex 1 in {X} and {Y}. The coordinates of hex 2 are
# then stored in {VAR}, which will have member variables x and y.
#
# Note that this uses the IF macro given earlier on this page.

#define OPPOSITE_SIDE CENTER_X CENTER_Y X Y VAR
    {VARIABLE x_odd {X}}

    {VARIABLE_OP x_odd modulo 2}

    {VARIABLE c_x {CENTER_X}}
    {VARIABLE c_y {CENTER_Y}}
    {VARIABLE s_x {X}}
    {VARIABLE s_y {Y}}

    {VARIABLE result_x {CENTER_X}}
    {VARIABLE result_y {CENTER_Y}}

    {IF_VAR s_x greater_than $c_x (
        [then]
            {VARIABLE_OP result_x add -1}
        [/then]
    )}

    {IF_VAR s_x less_than $c_x (
        [then]
            {VARIABLE_OP result_x add 1}
        [/then]
    )}

    {IF_VAR s_x equals $c_x (
        [then]
            {IF_VAR s_y less_than $c_y (
                [then]
                    {VARIABLE_OP result_y add 1}
                [/then]
            )}

            {IF_VAR s_y greater_than $c_y (
                [then]
                    {VARIABLE_OP result_y add -1}
                [/then]
            )}
        [/then]
    )}

    {IF_VAR x_odd equals 1 (
        [then]
            {IF_VAR s_y equals $c_y (
                [then]
                    {VARIABLE_OP result_y add 1}
                [/then]
            )}
        [/then]

        [else]
            {IF_VAR s_y equals $c_y (
                [then]
                    {VARIABLE_OP result_y add -1}
                [/then]
            )}
        [/else]
    )}
    {VARIABLE {VAR}.x $result_x}
    {VARIABLE {VAR}.y $result_y}

    {CLEAR_VARIABLE c_x}
    {CLEAR_VARIABLE c_y}
    {CLEAR_VARIABLE s_x}
    {CLEAR_VARIABLE s_y}
    {CLEAR_VARIABLE result_x}
    {CLEAR_VARIABLE result_y}
    {CLEAR_VARIABLE x_odd}
#enddef

Find nearest hex(es)

#define FIND_NEARBY FILTER X Y LIMIT
    # Does a search for a nearby location that matches the given filter.
    # Basically just looks for such a location with increasing radius until it
    # finds at least one. This is sadly inefficient, but implementing BFS in
    # WML is... difficult. Once LIMIT is reached, the entire map is searched.
    # This macro creates the 'nearby_locations' and 'nearby_distance'
    # variables, which can be used to access a list of locations found and the
    # distance to those locations, respectively. They should eventually be
    # cleared, which can be accomplished using the CLEANUP_SEARCH macro.
    [clear_variable]
        name=nearby_locations
    [/clear_variable]
    [set_variable]
        name=nearby_distance
        value=0
    [/set_variable]
    [while]
        [not]
            [variable]
                name=nearby_locations.length
                greater_than=0
            [/variable]
        [/not]
        [and]
            [variable]
                name=nearby_distance
                less_than={LIMIT}
            [/variable]
        [/and]
        [do]
            {DEBUG "Searching depth $nearby_distance around ({X}, {Y})..."}
            [store_locations]
                variable=nearby_locations
                {FILTER}
                [and]
                    x,y={X},{Y}
                    radius=$nearby_distance
                [/and]
            [/store_locations]
            {DEBUG "...found $nearby_locations.length locations."}
            [set_variable]
                name=nearby_distance
                add=1
            [/set_variable]
        [/do]
    [/while]
    [if]
        [variable]
            name=nearby_locations.length
            equals=0
        [/variable]
        [then]
            [store_locations]
                variable=nearby_locations
                {FILTER}
            [/store_locations]
        [/then]
    [/if]
#enddef

#define CLEANUP_SEARCH
    # Clears variables involved in searching (the FIND_NEARBY macro). Put this
    # in your name=victory,defeat tag to clean up if you use FIND_NEARBY within
    # a scenario.
    [clear_variable]
        name=nearby_locations, nearby_distance
    [/clear_variable]
#enddef

See Also

• UsefulWMLFragments
• ReferenceWML