WML Utilities

Test Value of Variables

# Shortcut for IF statements testing the value of a variable. You still need to
# write [then] and [else] tags manually, though.
#
# You can use it like this:
#
# {IF some_variable equals yes (
#     [then]
#         # something
#     [/then]
#
#     [else]
#         # something else
#     [/else]
# )}

#define IF VAR OP VAL CONTENTS
    [if]
        [variable]
            name={VAR}
            {OP}={VAL}
        [/variable]

        {CONTENTS}
    [/if]
#enddef

# Just a variation of the above, testing [have_unit] instead of [variable].

#define IF_HAVE_UNIT FILTER CONTENTS
    [if]
        [have_unit]
            {FILTER}
        [/have_unit]

        {CONTENTS}
    [/if]
#enddef

Store Attribute to Variable

# Example that flips all orcs to whatever side James is on:
#
# {STORE_UNIT_VAR description=James side side_of_James}
# {MODIFY_UNIT race=orc side $side_of_James}

#define STORE_UNIT_VAR FILTER VAR TO_VAR
    [store_unit]
        [filter]
            {FILTER}
        [/filter]

        kill=no
        variable=STORE_UNIT_VAR_store
    [/store_unit]

    {VARIABLE_OP {TO_VAR} format $STORE_UNIT_VAR_store.{VAR}}

    {CLEAR_VARIABLE STORE_UNIT_VAR_store}
#enddef 

Filter by Terrain

# Check whethers or not the terrain in the given coordinates is of the given
# type or types. Filtering by terrain isn't possible directly.
#
# You can use it for example like this:
#
# [event]
#     name=moveto
#     first_time_only=no
#
#     {IF_TERRAIN $x1 $y1 gfm (
#         [then]
#             {DEBUG_MSG "Stepped on grassland, forest or mountains!"}
#         [/then]
#     )}
# [/event]

#define IF_TERRAIN X Y TYPES CONTENTS
    [store_locations]
        x={X}
        y={Y}
        terrain={TYPES}
        variable=IF_TERRAIN_temp
    [/store_locations]
 
    [if]
        [variable]
            name=IF_TERRAIN_temp.length
            not_equals=0
        [/variable]
 
        {CONTENTS}
    [/if]
 
    {CLEAR_VARIABLE IF_TERRAIN_temp}
#enddef

Iterate

# You can iterate through a range of numbers with this macro. The CONTENTS
# are repeated with every iteration, and you can use the VAR variable to
# insert the number of the current step into each iteration. Note that
# when using this, you must iterate from a smaller number to the bigger
# number, because the increment is always 1.
#
# Example that spawns a row of skeletons into the coordinates (4,5),
# (5,5), (6,5), (7,5), (8,5) and (9,5):
#
# {ITERATE 4 9 i (
#     [unit]
#         type=Skeleton
#         x=$i
#         y=5
#     [/unit]
# )}

#define ITERATE FROM TO VAR CONTENTS
    {VARIABLE {VAR} {FROM}}

    [while]
        [variable]
            name={VAR}
            less_than_equal_to={TO}
        [/variable]

        [do]
            {CONTENTS}

            {VARIABLE_OP {VAR} add 1}
        [/do]
    [/while]
#enddef

General macros

#define FORMAT ARRAY VARIABLE
{VARIABLE_OP {VARIABLE} to_variable {ARRAY}.{VARIABLE}}
#enddef

##this is a "partial" macro; not all of the tags match up
#put {NEXT INDEX} after it
#define FOREACH_FORMAT ARRAY INDEX
 {FOREACH {ARRAY} {INDEX}}
  {FORMAT {ARRAY}[${INDEX}] x}
  {FORMAT {ARRAY}[${INDEX}] y}
#enddef

#define STORE_UNIT NAME
[store_unit]
 [filter]
 description={NAME}
 [/filter]
variable={NAME}_store
[/store_unit]
#enddef

#define UNSTORE_UNIT NAME X Y
{VARIABLE {NAME}_store.x {X}}
{VARIABLE {NAME}_store.y {Y}}
[unstore_unit]
variable={NAME}_store
[/unstore_unit]
{CLEAR_VARIABLE {NAME}_store}
#enddef

#define UNSTORE_ARRAY ARRAY
{FOREACH {ARRAY} i}
  [unstore_unit]
  variable={ARRAY}[$i]
  [/unstore_unit]
  [clear_variable]
  variable={ARRAY}[$i]
  [/clear_variable]
{NEXT i}
#enddef

More uncommon tasks

Adding unit overlays with a filter instead of (x,y)

# UNIT_OVERLAY adds an overlay to a unit, taking in a standard filter
#
# Example that gives all spearmen a book:
# {UNIT_OVERLAY type=Spearman items/book1.png}

#define UNIT_OVERLAY FILTER IMG
    [store_unit]
        [filter]
            {FILTER}
        [/filter]
        variable=UNIT_OVERLAY_store
        kill=no
    [/store_unit]
    {FOREACH UNIT_OVERLAY_store UNIT_OVERLAY_i}
	{VARIABLE_OP UNIT_OVERLAY_tempx format $UNIT_OVERLAY_store[$UNIT_OVERLAY_i].x}
	{VARIABLE_OP UNIT_OVERLAY_tempy format $UNIT_OVERLAY_store[$UNIT_OVERLAY_i].y}
        [unit_overlay]
            x=$UNIT_OVERLAY_tempx
            y=$UNIT_OVERLAY_tempy
		image={IMG}
        [/unit_overlay]
    {NEXT UNIT_OVERLAY_i}
    {CLEAR_VARIABLE UNIT_OVERLAY_store}
#enddef

Determining opposite coordinates

# 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 multiply 0.5}
    {VARIABLE_OP x_odd multiply 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 s_x greater_than $c_x (
        [then]
            {VARIABLE_OP result_x add -1}
        [/then]
    )}

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

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

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

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

        [else]
            {IF 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

See Also

• UsefulWMLFragments