This page documents details on JOSM's [http://wiki.openstreetmap.org/wiki/MapCSS/0.2 MapCSS] implementation.
[[TOC(inline)]]
== General Structure ==
A MapCSS style sheet has rules of the form
{{{
#!mapcss
selector {
    prop: value;
    /* ... */
    prop: value;
    /* and/or */
    set: class;
    set: .class;
}
}}}
The algorithm to find the styles for a given object is like this:
{{{
 - for each rule:
     if the selector applies, set the properties from the { } block
 - analyze the final list of properties and generate styles from it
}}}

MapCSS uses the '''comment''' format of CSS (`/* ... */`). Note that when commenting out large parts of a MapCSS file, some constructs may cause an unexpected end of the comment, for instance:
{{{
#!mapcss
/*
*[highway][name =~ /^R(\.|:)? .*/] { /* the end of the regular expression defines the unexpected end of the comment */
        throwWarning: tr("foo");
}
*/
}}} 

== Selectors ==
''Selectors'' denote the filter expressions of a MapCSS rule. The rule is only applied to a map object, if its selectors match
with the object.

Selectors in MapCSS are different from standard CSS for the web. MapCSS only supports a subset of the standard CSS selectors, but
extends them with additional selectors required for OSM data.

Some basic examples:
{{{
#!mapcss
/* applied to ways with a tag highway=residential */
way[highway=residential] {  /*  the styles */}

/* applied to new, closed ways on layer 1, provided they have the tag amenity=parking and access=public, and provided 
 * the zoom level is between 11 and 14 
 */
way|z11-14[amenity=parking][access=public]:closed:new::layer_1 {...}


area[amenity=parking][access=public], area[amenity=parking][!access] {...}
relation[type=route][route=foot] > way::relation_underlay {..}
}}}


The different elements ('''type'''-, '''zoom'''- , '''condition''' selector, '''pseudo classes''', '''layer identifier''', '''grouping''' and '''child combinator''') are explained below.


=== Type selector ===

{{{#!th align=left valign=top 
'''Selector'''
}}}
{{{#!th align=left valign=top
'''Description'''
}}}
|-------------------------------------------------------------------------------
{{{#!td align=left  valign=top
*
}}}
{{{#!td align=left  valign=top    
Matches with any object
}}}
|-------------------------------------------------------------------------------
{{{#!td align=left  valign=top
{{{node}}}, {{{way}}}, {{{relation}}}
}}}
{{{#!td align=left  valign=top    
Matches with the osm objects of the given type.
}}}
|-------------------------------------------------------------------------------
{{{#!td align=left  valign=top
{{{area}}}
}}}
{{{#!td align=left  valign=top    
Matches with any area regardless of whether the area border is only modelled with a single way or with a set of ways glued together with a relation.
{{{
#!mapcss
area[natural=beach] {...} 
/* ... is equal to ... */
way[natural=beach], relation[type=multipolygon][natural=beach] {...} 
}}}
Note that {{{area}}} selects unclosed ways as well, so it may be useful to add the {{{:closed}}} pseudo class. The JOSM Validator will give a warning for unclosed ways that have an area style.
}}}
|-------------------------------------------------------------------------------
{{{#!td align=left  valign=top
{{{meta}}}
}}}
{{{#!td align=left  valign=top    
The {{{meta}}} selector starts a special rule that should stand at the beginning of the file. It gives some general information on the style sheet. All software that supports MapCSS should be able to parse this sections without errors, so do not use exotic syntax extensions in this part.
{{{
#!mapcss
meta {
    title: "Parking lanes";   /* title shown in the menu */
    icon: "images/logo.png";  /* small icon shown in the menu next to the title */
    version: "1.2";           /* the version of the style */
    description: "...";       /* one or two sentences of describing the style */
    author: "...";            /* the author(s) of the style */
    link: "http://...";       /* URL to the web page of the style */
    min-josm-version: 6789;   /* the minimum JOSM version where this style works */
}
}}}
}}}
|-------------------------------------------------------------------------------
{{{#!td align=left  valign=top
{{{canvas}}}
}}}
{{{#!td align=left  valign=top    
Some style information not specific to nodes, ways or relations.
{{{
#!mapcss
canvas {
    fill-color: #ffffea; /* the former background-color is deprecated since r7110 */
    default-points: false;
    default-lines: false;
}
}}}
{{{#!th
'''Key'''
}}}
{{{#!th
'''Description'''
}}}
{{{#!th
'''Value Format'''
}}}
{{{#!th
'''Default Value'''
}}}
|-
{{{#!td
{{{fill-color}}}
}}}
{{{#!td
Specifies the overall fill/background color (`background-color` is deprecated since r7110).
}}}
{{{#!td
''Color''
}}}
{{{#!td align=center
{{{black}}}
}}}
|-
{{{#!td
{{{default-points}}}
}}}
{{{#!td
Whether default point style should be added to nodes where no style applies.
}}}
{{{#!td
''Boolean''
}}}
{{{#!td align=center
{{{true}}}
}}}
|-
{{{#!td
{{{default-lines}}}
}}}
{{{#!td
Whether default line style should be added to ways where no style applies.
}}}
{{{#!td
''Boolean''
}}}
{{{#!td align=center
{{{true}}}
}}}
}}}

=== Child selector ===
If a node is part of a way, we say that it is a ''child'' of this way. Similarly, if a node, a way, or a relation is a member
of a relation, we say, that it is a ''child'' of this relation.

In MapCSS you can use a '''child selector''' which matches only if both the parent and the child object match.

Example:
{{{
#!mapcss
/*
 * only matches for a way which is a child of a relation with tags 
 * type=route and route=foot
 */
relation[type=route][route=foot] > way {...}
}}}

Notes:
* Zoom selector and Layer identifier are only relevant for the part to the right of the > sign.
* The functions prop() and is_prop_set() are only supported on the right side of the > sign.
* The function parent_tag (see below) can be used to access tags from the parent.
* For compatibility with the MapCSS 0.2 standard, `relation[type=route][route=foot] way {/*...*/}`, without the greather-than-sign `>` is supported, too. However, no [[#Linkselector]] may be specified in this case.


=== Parent selector ===
In addition to child selectors, JOSMs supports the the notion of a '''parent selector'''. Note, that parent selectors are a 
JOSM-specific extension of MapCSS not present in other MapCSS implementations.

Similar to a child selector, a parent selector only matches if if both the parent and the child object match. In contrast to
to the child selector, the character < is used. 

In contrast to the child selector, the parent object will be "selected". In other words, the properties in the {{{{...}}}}-Declaration Block apply to the object on the right hand side of the "<" sign.

Example:
{{{
#!mapcss
/*
 * matches for a highway which has at least one node tagged as traffic_calming=*
 */
node[traffic_calming] < way[highway] {...}
}}}

=== Condition selector ===
Selectors can include a set of conditions. If any of these conditions evaluates to false, the selector doesn't match and the style
rule isn't applied.

An '''attribute condition''' specifies a condition on a tag of an OSM object. 

[=#condition_selector_operators]
{{{#!th align=left valign=top 
'''Operator'''
}}}
{{{#!th align=left valign=top
'''Description'''
}}}
{{{#!th align=left valign=top
'''Example'''
}}}
|-------------------------------------------------------------------------------
{{{#!td align=left  valign=top
`=`
}}}
{{{#!td align=left  valign=top    
Exact match of the value.
}}}
{{{#!td align=left  valign=top    
{{{
#!mapcss
way[highway=residential]                   /* without quotes always case insensitive */
node[name="My name"]                       /* use quotes for if value includes spaces or if case sensitive matching is important */
node["MY_Special_TAG"="another value"]     /* use quotes for tag names if case sensitive matching is required */
node["ÖPVN"=tram]                          /* use quotes for tag keys with special characters */
                                           /*   note that these are not common in OSM at the moment */
}}}
}}}
|-------------------------------------------------------------------------------
{{{#!td align=left  valign=top
`!=`
}}}
{{{#!td align=left  valign=top    
Value not equal 
}}}
{{{#!td align=left  valign=top    
{{{
#!mapcss
way[highway!=residential]                   /* without quotes always case insensitive */
node[name!="My name"]                       /* use quotes if value includes spaces or if case sensitive matching is important */
node["MY_Special_TAG"!="another value"]     /* use quotes for tag names if case sensitive matching is required */
node["name:fr"!="mon nome"]                 /* use quotes for tag names with special characters like colons*/
}}}
}}}
|-------------------------------------------------------------------------------
{{{#!td align=left  valign=top
`<`, `>`, `<=`, `>=`
}}}
{{{#!td align=left  valign=top    
Comparision for numeric values.

}}}
{{{#!td align=left  valign=top    
{{{
#!mapcss
node[population > 50000]                    /* without quotes always case insensitive */
node[ele <= 3000]                           /* use quotes for if value includes spaces or if case sensitive matching is important */
}}}
}}}
|-------------------------------------------------------------------------------
{{{#!td align=left  valign=top
{{{^=}}}
}}}
{{{#!td align=left  valign=top    
Prefix match
}}}
{{{#!td align=left  valign=top    
{{{
#!mapcss
node[name ^= "myprefix"]                    /* value starts with 'myprefix' */
}}}
}}}
|-------------------------------------------------------------------------------
{{{#!td align=left  valign=top
`$=`
}}}
{{{#!td align=left  valign=top    
Postfix match
}}}
{{{#!td align=left  valign=top    
{{{
#!mapcss
node[name $= "mypostfix"]                    /* value ends with 'mypostfix' */
}}}
}}}
|-----------------------------------------------
{{{#!td align=left  valign=top
`*=`
}}}
{{{#!td align=left  valign=top    
Substring match
}}}
{{{#!td align=left  valign=top    
{{{
#!mapcss
node[name *= "my substring"]                  /* value contains the substring 'my substring' */
}}}
}}}
|-------------------------------------------------------------------------------
{{{#!td align=left  valign=top
`~=`
}}}
{{{#!td align=left  valign=top    
List membership
}}}
{{{#!td align=left  valign=top    
{{{
#!mapcss
*[vending~=stamps]                          /* the tag value for the tag 'vending' consists of a list of ;-separated values    */
                                            /* and one of these values is 'stamps'                                             */
}}}
}}}
|-------------------------------------------------------------------------------
{{{#!td align=left  valign=top
`=~`
}}}
{{{#!td align=left  valign=top    
[http://download.oracle.com/javase/6/docs/api/java/util/regex/Pattern.html#sum Regular expression] match

}}}
{{{#!td align=left  valign=top    
{{{
#!mapcss
name[name=~/^My_pattern.*/]                 /* the value of the tag 'name' matches with the regular expression '^My_pattern.*' */
                                            /* Note, that reqular expressions have to be enclosed in /.../                     */                  
}}}
Case-insensitive matching can be enabled via the embedded flag expression `(?i)` (see [http://docs.oracle.com/javase/6/docs/api/java/util/regex/Pattern.html#CASE_INSENSITIVE Pattern.CASE_INSENSITIVE]).
}}}
|-------------------------------------------------------------------------------
{{{#!td align=left  valign=top
`!~` (since r6455)
}}}
{{{#!td align=left  valign=top    
negated [http://download.oracle.com/javase/6/docs/api/java/util/regex/Pattern.html#sum Regular expression] match

}}}
{{{#!td align=left  valign=top    
{{{
#!mapcss
*[surface!~/paved|unpaved/]
}}}
}}}
|-------------------------------------------------------------------------------
{{{#!td align=left  valign=top
`∈` ([http://www.fileformat.info/info/unicode/char/2208/index.htm U+2208], since r6609)
}}}
{{{#!td align=left  valign=top    
element of

}}}
{{{#!td align=left  valign=top    
{{{
#!mapcss
node[amenity=parking] ∈ *[amenity=parking] {
  throwWarning: tr("{0} inside {1}", "amenity=parking", "amenity=parking");
}
}}}
}}}
|-------------------------------------------------------------------------------
{{{#!td align=left  valign=top
`⧉` ([http://www.fileformat.info/info/unicode/char/29c9/index.htm U+29C9], since r6613)
}}}
{{{#!td align=left  valign=top    
crossing

}}}
{{{#!td align=left  valign=top    
{{{
#!mapcss
area:closed:areaStyle ⧉ area:closed:areaStyle {
  throwOther: tr("Overlapping Areas");
}
}}}
}}}

Since r6554, it is possible to prefix the "value" (i.e., expression after the operator) with a `*` in order to "de-reference" it (i.e., obtain consider it as another key and obtain its value). Thus, `[key1 = *key2]` compares the value of `key1` with the value of `key2`, and `[key =~ */pattern/]` considers the value of the key `pattern` as a regular expression and matches it against the value of `key`.

In addition, you can test whether a tag is present or not:

{{{#!th align=left valign=top 
'''Condition'''
}}}
{{{#!th align=left valign=top
'''Example'''
}}}
|-------------------------------------------------------------------------------
{{{#!td align=left  valign=top
Presence of tag
}}}
{{{#!td align=left  valign=top    
{{{
#!mapcss
way[highway]                     /* matches any way with a tag 'highway'                                              */
way["VALSOU"]                    /* use quotes if case sensitive matching is required                                 */
way["name:fr"]                   /* use quotes if the tag name includes special caracters (white space, colons, etc.) */
}}}
}}}
|-------------------------------------------------------------------------------
{{{#!td align=left  valign=top
Absence of tag
}}}
{{{#!td align=left  valign=top    
{{{
#!mapcss
way[!highway]                     /* matches any way which does not have a tag 'highway'                                              */
way[!"VALSOU"]                    /* use quotes if case sensitive matching is required                                 */
way[!"name:fr"]                   /* use quotes if the tag name includes special caracters (white space, colons, etc.) */
}}}
}}}
|-------------------------------------------------------------------------------
{{{#!td align=left  valign=top
Presence of tag by [http://download.oracle.com/javase/6/docs/api/java/util/regex/Pattern.html#sum Regular expression] match (since r6547)
}}}
{{{#!td align=left  valign=top    
{{{
#!mapcss
way[/^addr:/]                     /* matches any `addr:*` key */
}}}
}}}

You can test whether the the value of a tag is logical truth value. The value is evaluated to true, if it is either 
"yes", "true", or "1". All other values are evaluated to false.

{{{#!th align=left valign=top 
'''Condition'''
}}}
{{{#!th align=left valign=top
'''Example'''
}}}
|-------------------------------------------------------------------------------
{{{#!td align=left  valign=top
Testing for truth value
}}}
{{{#!td align=left  valign=top    
{{{
#!mapcss
way[oneway?]                  /* matches any way with a truth value in the tag 'oneway'  */
}}}
}}}
|-------------------------------------------------------------------------------
{{{#!td align=left  valign=top
Testing for false value (since r6513)
}}}
{{{#!td align=left  valign=top    
{{{
#!mapcss
way[oneway?!]                  /* matches any way with a false value in the tag 'oneway'  */
}}}
}}}

=== Link selector ===
In a child selector, you can formulate conditions on the link between a parent and a child object. 

If the parent is a relation, you can formulate conditions for the ''role'' a member objects has in this relation.
{{{
#!mapcss
relation[type=route] >[role="link"] way {  /* matches any way which is a member of route relation with role 'link' */ 
   color: blue;
}
}}}

{{{#!th align=left valign=top 
'''Operator'''
}}}
{{{#!th align=left valign=top
'''Description'''
}}}
{{{#!th align=left valign=top
'''Example'''
}}}
|-------------------------------------------------------------------------------
{{{#!td align=left  valign=top
`=`
}}}
{{{#!td align=left  valign=top    
Exact match of the role name. The name name {{{role}}} is compulsory in this context. 
}}}
{{{#!td align=left  valign=top    
{{{
#!mapcss
relation >[role=residential] way           /* without quotes always case insensitive */
relation >[role="My name"]   way           /* use quotes for if the role value includes spaces or if case sensitive matching is important */
}}}
}}}

The operators {{{!=, ^=, $=, *=, and ~=}}} are supported too. Please refer to [#condition_selector_operators condition selector operators].

Nodes in ways and members in relations are ordered. You can formulate conditions on the position of a node in a way or a member
object in a relation. 

{{{
#!mapcss
relation[type=route] >[index=1] way {  /* matches the first way which is a member of route relation  */ 
   color: blue;
}
}}}


=== Zoom selector ===
You can decorate a type selector with a '''zoom selector'''. The zoom selector restricts the range of zoom levels 
at which the respective MapCSS rule is applied.

{{{#!th align=left valign=top 
'''Example'''
}}}
{{{#!th align=left valign=top
'''Description'''
}}}
|-------------------------------------------------------------------------------
|| {{{way|z12 {...} }}} || At zoom level 12 ||
|| {{{way|z13-15 {...} }}} || From 13 to 15 ||
|| {{{way|z16- {...} }}} || 16 and above ||
|| {{{way|z-12 {...} }}} || 12 and below ||
|| {{{way {...} }}} || any zoom level ||

The precise definition of scale ranges for each zoom level may change in the future. By rule of thumb you can expect to be approximately at zoom level ''n'' when imagery displays slippymap tiles of level ''n''.


=== Pseudo Classes ===

|| {{{:closed}}} || true for ways where the first node is the same as the last and for any multipolygon relation ||
|| {{{:new}}} || all new objects ||
|| {{{:connection}}} || true for nodes that are used by more than one way ||
|| {{{:unconnected}}} || true for nodes that are not used by any way (since r6687) ||
|| {{{:tagged}}} || What JOSM considers tagged, i.e. an object that with a tag key other than the following: {{{source*, source_ref, note, comment, converted_by, created_by, watch*, fixme, FIXME, description, attribution}}} (version r4008; in this list, {{{*}}} is a glob)
|| {{{:righthandtraffic}}} || true if there is right-hand traffic at the current location ||
{{{#!comment
|| {{{:modified}}} || changed objects (Note that the styles are not updated when you move a node, so you have to switch the style sheet on and off to get an updated view.) (since r7193) ||
}}}
=== Layer Identifier ===

Layers can be used to create more than one style for a single object. Here is an example:
{{{
#!mapcss
way[highway=secondary] {
    width: 3;
    color: yellow;
}

way[highway=tertiary] {
    width: 2;
    color: orange;
}

way[access][access!=public]::non_public_access_layer {
    width: +2; 
    color:red; 
    dashes: 2; 
    object-z-index:-1.0;
}

way[bridge]::bridge_layer {
    width: +3; 
    color:#000080;
    opacity:0.5;
    object-z-index:1.0; 
}
}}}
This draws all secondary and tertiary roads in yellow and orange respectively. Any road with an access tag other than public will get an extra line style below ('''{{{object-z-index:-1.0;}}}''') the main line. If that part of the street happens to be a bridge, it will also get a half transparent blue overlay. The relative width value ('''{{{width: +2;}}}''') refers to the width on the default layer (2 or 3 in this case).

The name for the layer can be any identifier.

 default::
 If you omit the layer in the selector, this is the same as using {{{::default}}}. 
 *::
 In addition, you can use the * layer to override and initialize all layers.[[br]]
 It overrides all existing subparts, so
{{{
#!mapcss
way::A { a; } 
way::B { b; } 
way::* { c; } 
}}}
 is equivalent to
{{{
#!mapcss
way::A { a; } 
way::B { b; } 
way::A { c; } 
way::B { c; }
}}}
 And it initializes new subparts. In other words: 
{{{
#!mapcss
way::* { a; } 
way::A { b; } 
}}}
 is equivalent to 
{{{
#!mapcss
way::A {} 
way::* { a; } 
way::A { b; } 
}}}
 which is in turn the same as 
{{{
#!mapcss
way::A { a; } 
way::A { b; } 
}}}
 or
{{{
#!mapcss
way::A { a; b; }
}}}


=== Grouping ===

Rules with common declaration block can be grouped into one:
{{{
#!mapcss
area[landuse=forest] { color: green;   width: 2; }
area[natural=wood] { color: green;   width: 2; }
}}}
is the same as
{{{
#!mapcss
area[landuse=forest], area[natural=wood] { color: green;   width: 2; }
}}}

=== Classes ===
You may assign classes to matched elements, and define other selectors using those classes:

{{{
#!mapcss
/* assigning classes */
selector {
  set class;
  /* or equivalently */
  set .class;
}

/* matching classes */
way.class, node[foo=bar].class {
  /* ... */
}
}}}


Example for assigning/matching a class named `path`:
{{{
#!mapcss
way[highway=footway] { set path; color: #FF6644; width: 2; }
way[highway=path]    { set path; color: brown; width: 2; }
way.path { text:auto; text-color: green; text-position: line; text-offset: 5; }
}}}

== Media queries [''since 6970''] ==

Media queries are used to skip a section of the style under certain conditions. Typically you want to use a feature which is introduced in a newer version of JOSM, but like to have a fall back style for users of older JOSM clients. Example:
{{{
#!mapcss
@media (min-josm-version: 9789) {
    way[highway] {
        width: 4;
        color: orange;
    }
    /* fancy new stuff */
    /* ... */
}

@media (max-josm-version: 9788) {
    way[highway] {
        width: 4;
        color: blue;
    }
    /* fall back mode, using more simple features */
    /* ... */
}
}}}

The syntax closely matches the official [http://www.w3.org/TR/css3-mediaqueries/#syntax css syntax]. The following conditions are supported:

{{{#!th
'''Media condition'''
}}}
{{{#!th
'''Description'''
}}}
|-
{{{#!td
(min-josm-version: ''<number>'')
}}}
{{{#!td
Only include {{{@media}}} section when the current version of JOSM is greater than or equal to the specified number.
}}}
|-
{{{#!td
(max-josm-version: ''<number>'')
}}}
{{{#!td
Only include {{{@media}}} section when the current version of JOSM is lower than or equal to the specified number.
}}}
|-
{{{#!td
(user-agent: ''<string>'')
}}}
{{{#!td
Only include {{{@media}}} section when the name of the editor / renderer matches the given string. In JOSM, the only accepted value is {{{josm}}}. 
}}}

Conditions can be combined with {{{and}}}:

{{{
#!mapcss
@media (min-josm-version: 6970) and (max-josm-version: 7014) {
 /* only for JOSM versions 6970 to 7014 */
}
}}}

Multiple combined conditions can be chained with a comma (logical ''or''):

{{{
#!mapcss
@media (min-josm-version: 6970) and (max-josm-version: 7014), (user-agent: myEditor) {
  /* for JOSM version 6970 to 7014 and for the editor called "myEditor" */
}
}}}

Since media queries are only supported in JOSM 6970 and later, you should also specify this as minimum JOSM version in the meta selector:

{{{
#!mapcss
meta {
    min-josm-version: "6970"; /* This style uses media queries */
    /* ... */
}
}}}


{{{#!comment
There is also the {{{not}}} keyword (see the linked css doc for details).
This is implemented, but probably not very useful. Feel free to add documentation.
}}}

== Properties ==

=== General properties ===

||=  '''Key''' =||= '''Description''' =||= '''Value Format''' =||= '''Default Value''' =||
|| {{{z-index}}}                                 || Specify the order the objects are drawn: The objects with higher z-index are drawn on top of objects with lower z-index || ''Number'' (can be negative) ||  0  ||
|| {{{major-z-index}}} || Similar to {{{z-index}}}, but it has higher priority than {{{z-index}}}. So if one object has a higher {{{major-z-index}}} than the other, it is drawn on top. If the {{{major-z-index}}} is the same, {{{z-index}}} decides. || ''Number'' (can be negative) ||  Depends on style element: area: 1, casing: 2, left-/right-casing: 2.1, line-pattern: 2.9, line: 3, point: 4, default-point: 4.1, line-text: 4.9, point-text: 5   ||
|| {{{object-z-index}}} || Similar to {{{z-index}}}, but has lower priority. Controls the painting order for overlapping objects. E.g. for two crossing ways with text: Use {{{z-index}}} or {{{major-z-index}}} if you first want to draw the two lines and then the two captions. Use {{{object-z-index}}} if one of the ways should be completely on top of the other. || ''Number'' (can be negative) ||  0  ||
|| {{{modifier}}} || Better control, whether a default line / node symbol is generated by JOSM. This happens when there is no proper style ({{{modifier=false}}}) found on any layer. || {{{false}}} or {{{true}}} || {{{false}}} for the default layer and {{{true}}} for any other layer ||



=== Icon and symbol styles ===

||=  '''Key''' =||= '''Description''' =||= '''Value Format''' =||= '''Default Value''' =||
|| {{{icon-image}}} || The icon at node position || ''Image'' ||  -  ||
|| {{{icon-opacity}}} || Opacity of the icon image || ''Opacity'' ||  1.0  ||
|| {{{icon-width}}} || Width of the icon. If only one of the properties {{{icon-width}}} and {{{icon-height}}} is given, the image will be scaled proportionally. The icon will keep the original size, if neither {{{icon-width}}} nor {{{icon-height}}} is set. || ''Number'' ||  -  ||
|| {{{icon-height}}} || Height of the icon. (See {{{icon-width}}}) || ''Number'' ||  -  ||
|| {{{symbol-shape}}}                               || Display a symbol at the position of the node || {{{square}}}, {{{circle}}}, {{{triangle}}}, {{{pentagon}}}, {{{hexagon}}}, {{{heptagon}}}, {{{octagon}}}, {{{nonagon}}}, {{{decagon}}} ||  -  ||
|| {{{symbol-size}}} || Size of the symbol || ''Number'', can be relative ("+4") ||  10  ||
|| {{{symbol-stroke-width}}} || outline stroke width || ''Width'' ||  1.0 if {{{symbol-stroke-color}}} is set  ||
|| {{{symbol-stroke-color}}} || line color || ''Color'' || {{{#FFC800}}} if {{{symbol-stroke-width}}} is set ||
|| {{{symbol-stroke-opacity}}} || line opacity || ''Opacity'' ||  1.0  ||
|| {{{symbol-fill-color}}} || fill color for the shape || ''Color'' || {{{blue}}}, unless either {{{symbol-stroke-width}}} or {{{symbol-stroke-color}}} is set ||
|| {{{symbol-fill-opacity}}} || fill opacity || ''Opacity'' ||  1.0  ||
|| {{{text-...}}}, {{{font-...}}} ||||||  general text & font properties  ||
|| {{{text-anchor-horizontal}}} || horizontal text label placement || {{{left}}}, {{{center}}}, {{{right}}} ||  {{{right}}}  ||
|| {{{text-anchor-vertical}}} || vertical text label placement || {{{above}}}, {{{top}}}, {{{center}}}, {{{bottom}}}, {{{below}}} ||  {{{bottom}}}  ||

Do not rely on the default values for {{{symbol-...}}} properties (except for {{{opacity}}}). They are intended for "quick & dirty" style sheets and should be set to an explicit value.





=== Line styles ===
||=  '''Key''' =||= '''Description''' =||= '''Value Format''' =||= '''Default Value''' =||
|| {{{width}}} || Line width || ''Width'' ||  -  ||
|| {{{color}}} || Line color || ''Color'' ||  value of {{{fill-color}}} or (if unset) JOSM's default untagged color ({{{#808080}}}) ||
|| {{{opacity}}} || How transparent the line is. || ''Opacity'' ||  1.0  ||
|| {{{dashes}}} || An array of alternating on/off lengths || list of numbers, e.g. [[br]]> 15, 5 [[br]][[br]]may be written as expression: [[br]] > {{{list(3, 4, 5, 6)}}} [[br]][[br]]or the keyword {{{none}}}[[br]]to turn dashes off ||  -  ||
|| {{{dashes-offset}}} || shift the dash pattern by a certain amount || ''Number'' (>= 0) ||  0  ||
|| {{{dashes-background-color}}} || The color to use in between the dashes (optional) || ''Color'' ||  -  ||
|| {{{dashes-background-opacity}}} || Opacity value for the dashes background || ''Opacity'' ||  value of {{{opacity}}}  ||
|| {{{linecap}}} || Shape at the end of the line (see [http://www.w3.org/TR/SVG/painting.html#StrokeLinecapProperty here]) || {{{none}}}, {{{round}}}, {{{square}}} ||  {{{none}}}  ||
|| {{{linejoin}}} || Shape at the line corners || {{{round}}}, {{{miter}}}, {{{bevel}}} ||  {{{round}}}  ||
|| {{{miterlimit}}}                                   || Applies for {{{linejoin: miter}}}. Sets the maximum overshoot when line segments meet at a very small angle || ''Number'' (>= 1.0) ||  10.0  ||
|| {{{offset}}} || Move line to the left or right (when looking in way direction). This could be used to draw multiple lanes for one way or mark left and right side of a way differently. || ''Number'' (positive value moves line to the left, negative to the right) ||  0  ||
|| {{{text-position}}} || set to {{{line}}}, if text should be drawn along the line || {{{line}}}, {{{center}}} ||  -  ||
|| {{{text-...}}}, {{{font-...}}} ||||||  general text & font properties  ||
|| `repeat-image` || repeated image along a line ''[since 5801]'' || ''Image'' ||  -  ||
|| `repeat-image-width` || Width of the image (optional, see `icon-width`) ''[since 5811]'' || ''Number'' ||  -  ||
|| `repeat-image-height` || Height of the image (optional) ''[since 5811]'' || ''Number'' ||  -  ||
|| `repeat-image-align` || Alignment of the image. Top-, bottom edge or the (horizontal) center line of the image will be along the line ''[since 5801]'' || `top`, `center`, `bottom` ||  `center`  ||
|| `repeat-image-offset` || Offset from the line ''[since 5801]'' || ''Number'' ||  0  ||
|| `repeat-image-spacing` || Spacing between repeated images ''[since 5801]'' || ''Number'' ||  0  ||
|| `repeat-image-phase` || Initial spacing at the beginning of the line ''[since 5812]'' || ''Number'' ||  0  ||

All these properties (except for {{{text-...}}} and {{{font-...}}}) exist also with the {{{casing-}}} prefix. The casing is a second independent line element, that is drawn below the normal line and can be used to draw a thin frame around the line in another color.
||=  '''Key''' =||= '''Description''' =||= '''Value Format''' =||= '''Default Value''' =||
|| {{{casing-width}}}               || Width of the border on both sides of the main line. In JOSM < 5214: Total width of the casing || ''Width'' (revers to {{{width}}} if relative width is specified) ||  -  ||
|| {{{casing-color}}} || Casing color || ''Color'' ||  value of {{{fill-color}}} or (if unset) JOSM's default untagged color ({{{#808080}}}) ||
|| {{{casing-opacity}}} || How transparent the casing is. || ''Opacity'' ||  1.0  ||
|| {{{casing-}}}... || ... || ... ||  ...  ||
Similar to {{{casing-}}}, there is also the {{{left-casing-}}} and {{{right-casing-}}} prefix. It draws additional lines to the left and to the right of the main line.

=== Area styles ===
||=  '''Key''' =||= '''Description''' =||= '''Value Format''' =||= '''Default Value''' =||
|| {{{fill-color}}} || Color in which to fill the area || ''Color'' ||  -  ||
|| {{{fill-image}}} || Image pattern || ''Image'' ||  -  ||
|| {{{fill-opacity}}} || How transparent the fill is; applies to both color and image || ''Opacity'' ||  1.0  ||
|| {{{text-position}}} || set to {{{center}}}, if text should be drawn in the center of the area || {{{line}}}, {{{center}}} ||  -  ||
|| {{{text-...}}}, {{{font-...}}} ||||||  general text & font properties  ||
Required properties to create an Area style: {{{fill-color}}} or {{{fill-image}}} 


=== Text & Font properties ===
{{{#!th align=left valign=top 
'''Key'''
}}}
{{{#!th align=left valign=top
'''Description'''
}}}
{{{#!th align=left valign=top
'''Value Format'''
}}}
{{{#!th align=left valign=top
'''Default Value'''
}}}
|-------------------------------------------------------------------------------
{{{#!td align=left  valign=top
{{{text}}}  
}}}
{{{#!td align=left  valign=top
How to find the label text. No label is displayed, unless this instruction is present.
}}}
{{{#!td align=left  valign=top
{{{auto}}}
   Derive the text automatically. The default name tags are: "{{{name:}}}"+''<LANG>'', "{{{name}}}", "{{{int_name}}}", "{{{ref}}}", "{{{operator}}}", "{{{brand}}}" and "{{{addr:housenumber}}}". 

   Configure a list of tag names in the preference "{{{mappaint.nameOrder}}}" in order to change this list.

''String''
   Denotes the key of the tag whose value is used as text.

''Expressions''
  You can enter an expression to compute the text to be displayed. Examples:
  * {{{eval("this is a static text")}}} - renderes a static text
  * {{{eval(concat(tag("first"), "-", tag("second")))}}} - displays the concatenated tags "first" and "second" 
}}}
{{{#!td align=center  valign=top
-
}}}
|-------------------------------------------------------------------------------
|| {{{text-color}}} || the text color || ''Color'' ||  {{{white}}} for lines and nodes, {{{#c0c0c0}}} for areas (JOSM "{{{text}}}" and "{{{areatext}}}" color preferences) ||
|| {{{text-opacity}}} || how transparent the text is || ''Opacity'' ||  1.0  ||
|| {{{text-offset-x}}} || shift the text horizontally, (not supported for text along line) || ''Number'' ||  0  ||
|| {{{text-offset-y}}} (can also be written as {{{text-offset}}})  || shift the text vertically, positive values shift the text in upwards direction  || ''Number'' ||  0  ||
|| {{{text-halo-radius}}} || size of text background border (to make text visible on background with a similar color) || ''Number'' ||  -  ||
|| {{{text-halo-color}}} || color of the text halo || ''Color'' ||  complement of the text color  ||
|| {{{text-halo-opacity}}} || transparency for the text halo || ''Opacity'' ||  1.0  ||
|| {{{font-family}}} || font family || ''String'' ||  "Helvetica"[[br]](JOSM preference "mappaint.font")  ||
|| {{{font-size}}} || font size || ''Number'' ||  8[[br]](JOSM preference "mappaint.fontsize")  ||
|| {{{font-weight}}} || bold or not || {{{bold}}}, {{{normal}}} ||  {{{normal}}}  ||
|| {{{font-style}}} || italic or not || {{{italic}}}, {{{normal}}} ||  {{{normal}}}  ||

'' '''Width''' ''
 - 14.0 (any positive number)
 - {{{default}}} (use JOSM's default line width, which is 2, but can be configured) 
 - {{{thinnest}}} (draws the line as thin as possible) 
 - +3 (with plus sign in front) adds the amount to the width on the default layer. This applies only for styles that are not on the default layer, e.g. highlights. Another way to write this would be {{{prop("width","default")+3}}}. For {{{casing-width}}}, this refers to the {{{width}}} value on the same layer.

'' '''Image''' ''
 See [wiki:Help/Styles/Images].

'' '''Color''' ''
 * named color as found in [http://www.w3.org/TR/css3-color/#svg-color this] list
 * html style: '''{{{#RRGGBB}}}''', '''{{{#RGB}}}''', '''{{{#RRGGBBAA}}}'''
 * '''{{{rgb(/*r*/, /*g*/, /*b*/)}}}''' - rgb value with arguments from 0.0 to 1.0
 * '''{{{rgba(/*r*/, /*g*/, /*b*/, /*alpha*/)}}}''' - rgb value with alpha
 * '''{{{hsb_color(/*hue*/, /*saturation*/, /*brightness*/)}}}''' - color from HSB color space

'' '''Opacity''' ''
 * from 0.0 (transparent) to 1.0 (opaque)

'' '''String''' ''
 * any character sequence, in quotes, e.g. {{{"images/fill.png"}}}. If the string is an identifier, quotes are optional. (Quote and backslash sign can be escaped.)

'' '''Number''' ''
 * integer or floating point (in simple form e.g. 0.3). In general can be negative, but most properties do not support negative numbers
 * has a special meaning if you put a "+" sign in front (relative width)

== Eval expressions ==


See [http://josm.openstreetmap.de/doc/org/openstreetmap/josm/gui/mappaint/mapcss/ExpressionFactory.Functions.html#method_summary Javadoc of Functions] for the up-to-date list of functions supported by JOSM's MapCSS implementation.

 +, -, *, /::
  arithmetic operations
 ||, &&, !::
  boolean operations
 <, >, <=, >=, ==::
  comparison operators
 asin, atan, atan2, ceil, cos, cosh, exp, floor, log, max, min, random, round, signum, sin, sinh, sqrt, tan, tanh::
  the usual meaning, [http://download.oracle.com/javase/6/docs/api/java/lang/Math.html details]
 cond(b, fst, snd)::
 b ? fst : snd::
  if ('''b''') then '''fst''' else '''snd'''
 list(a, b, ...)::
  create list of values, e.g. for the {{{dashes}}} property
 get(lst, n)::
  get the ''n''th element of the list ''lst'' (counting starts at 0) [''since 5699'']
 split(sep, str)::
  splits string ''str'' at occurrences of the separator string ''sep'', returns a list [''since 5699'']
 prop(''p_name'')::
  value of the property ''p_name'', e.g. prop({{{"width"}}})
 prop(''p_name'', ''layer_name'')::
  property from the layer ''layer_name''
 is_prop_set(''p_name'')::
  true, if property ''p_name'' is set
 is_prop_set(''p_name'', ''layer_name'')::
  true, if property ''p_name'' is set
 tag(''key_name'')::
  get the value of the key ''key_name'' from the object in question
 parent_tag(''key_name'')::
  get the value of the key ''key_name'' from the object's parent(s)
 has_tag_key(''key_name'')::
  true, if the object has a tag with the given key
 rgb(''r'', ''g'', ''b'')::
  create color value (arguments from 0.0 to 1.0)
 hsb_color(''h'', ''s'', ''b'')::
  create color from hue, saturation and brightness (arguments from 0.0 to 1.0) [''since 6899'']
 red(''clr''), green(''clr''), blue(''clr'')::
  get value of color channels in rgb color model
 alpha(''clr'')::
  get the alpha value of the given color [''since 6749'']
 length(''str'')::
  length of a string
 count(''lst'')::
  length of a list, i.e., counts its elements [''since 7162'']
 length(''lst'')::
  length of a list [''since 5699''] – deprecated ''since 7162''
 any(obj1, obj2, ...)::
  returns the first object which is not null (formerly coalesce, [''since 7164''])
 concat(''str1'', ''str2'', ...)::
  assemble the strings to one
 join(''sep'', ''str1'', ''str2'', ...)::
  join strings, whith ''sep'' as separator [''since 6737'']
 JOSM_search("...")::
  true, if JOSM search applies to the object
 tr(str, arg0, arg1, ...)::
  translate from English to the current language (only for strings in the JOSM user interface) [''since 6506'']
 regexp_test(regexp, string)::
  test if ''string'' matches pattern ''regexp'' [''since 5699'']
 regexp_test(regexp, string, flags)::
  test if ''string'' matches pattern ''regexp''; flags is a string that may contain "i" (case insensitive), "m" (multiline) and "s" ("dot all") [''since 5699'']
 regexp_match(regexp, string)::
  Tries to match ''string'' against pattern ''regexp''. Returns a list of capture groups in case of success. The first element (index 0) is the complete match (i.e. ''string''). Further elements correspond to the bracketed parts of the regular expression. [''since 5701'']
 regexp_match(regexp, string, flags)::
  Tries to match ''string'' against pattern ''regexp''. Returns a list of capture groups in case of success. The first element (index 0) is the complete match (i.e. ''string''). Further elements correspond to the bracketed parts of the regular expression. Flags is a string that may contain "i" (case insensitive), "m" (multiline) and "s" ("dot all") [''since 5701'']
 substring(str, idx)::
  return the substring of ''str'', starting at index ''idx'' (0-indexed) [''since 6534'']
 substring(str, start, end)::
  return the substring of ''str'', starting at index ''start'' (inclusive) up to ''end'' (exclusive) (0-indexed) [''since 6534'']
 replace(string, old, new)::
   Replaces any occurrence of the substring ''old'' within the string ''string'' with the text ''new'' 
 osm_id()::
  returns the OSM id of the current object [''since 5699'']
 URL_encode(str)::
  [https://en.wikipedia.org/wiki/Percent-encoding percent-encode] a string. May be useful for data URLs [''since 6805'']
 XML_encode(str)::
  escape special characters in xml. E.g. {{{<}}} becomes {{{&lt;}}}, other special characters: {{{>}}}, {{{"}}}, {{{'}}}, {{{&}}}, {{{\n}}}, {{{\t}}} and {{{\r}}} [''since 6809'']
 CRC32_checksum(''str'')::
  calculate the CRC32 checksum of a string (result is an integer from 0 to 2^32^-1) [''since 6908'']
 is_right_hand_traffic() [''since 7193'']::
  Check if there is left-hand or right-hand traffic at the current location.
 number_of_tags() [''since 7237'']::
  returns the number of tags for the current OSM object
 print(o) [''since 7237'']::
  prints a string representation of `o` to the command line (for debugging)
 println(o) [''since 7237'']::
  prints a string representation of `o` to the command line, followed by a new line (for debugging)
 JOSM_pref(''key'', ''default'') [''since 7238'']::
  Get value from the JOSM advanced preferences. This way you can offer certain options to the user and make the style customizable. It works with strings, numbers, colors and boolean values.






=== Examples ===

* circle symbol for house number with size depending of the number of digits
{{{
#!mapcss
node[addr:housenumber] { 
    symbol-shape: circle; 
    symbol-size: eval((min(length(tag("addr:housenumber")), 3) * 5) + 3); 
    symbol-fill-color: #B0E0E6; 

    text: "addr:housenumber"; 
    text-anchor-horizontal: center; 
    text-anchor-vertical: center; 
    text-offset-x: -1; 
    text-offset-y: -1; }
    
node[addr:housenumber]::hn_casing { 
    z-index: -100; 
    symbol-shape: circle; 
    symbol-size: +2; 
    symbol-fill-color: blue; 
}
}}}
* invert colors
{{{
#!mapcss
*::* {
    color: eval(rgb(1 - red(prop(color)), 1 - green(prop(color)), 1 - blue(prop(color))));
    fill-color: eval(rgb(1 - red(prop(fill-color)), 1 - green(prop(fill-color)), 1 - blue(prop(fill-color))));
}
}}}
* random stuff
{{{
#!mapcss
way {
    width: eval(random() * 20);
    color: eval(rgb(random(), random(), random()));
}
}}}

* regexp matching example: change "nameXXXsubname" to "name::subname"
{{{
#!mapcss
*[name=~/.+XXX.+/] 
{
    _match: regexp_match("(.+?)XXX(.+)", tag("name"));
    text: concat(get(prop("_match",1), "::", get(prop("_match"),2));
}
}}}

* paint buildings in different colors according to street in the address tags
{{{
#!mapcss
area[building][addr:street] {
    fill-color: hsb_color(CRC32_checksum(tag("addr:street"))/4294967296.0, 0.9, 0.7);
    fill-opacity: 0.8;
}
}}}


== Compatibility notes ==
=== MapCSS 0.2 ===

==== Grammar ====

 * {{{way[oneway=yes]}}} does not have any magic, you can use {{{way[oneway?]}}} instead
 * no {{{@import}}}
 * JOSM does not require {{{eval(...)}}} to be wrapped around expressions, but for compatibility with other MapCSS implementations you should write it out.

==== Properties ====
At the moment, JOSM does ''not'' support the following properties: 
 line: ::
  {{{image}}}
 label: ::
  {{{font-variant, text-decoration, text-transform, max-width}}}
 shield: ::
  not supported

=== Halcyon (Potlatch 2) ===

 * Text label is placed in the center of the icon. For compatibility with Halcyon put
{{{
#!mapcss
node { text-anchor-vertical: center; text-anchor-horizontal: center; }
}}}
 at the beginning of your style sheet.
 * standard z-index in Halcyon is 5, but it is 0 in JOSM
 * '''{{{image: circle;}}}''' corresponds to '''{{{symbol-shape: circle;}}}'''

=== Kothic ===

 * Kothic has support for eval, which probably differs from JOSM's eval.
 * Kothic understands units, whereas JOSM always calculates in pixel.
 * The extrusion features are not available in JOSM

=== Ceyx ===

 * seems to have {{{[tunnel=1]}}} instead of {{{[tunnel=yes]}}} (Halcyon) or {{{[tunnel?]}}} (JOSM)