[[TranslatedPages]]

= [[Image(layerchecker.svg,36,middle)]] Layer checker =
[[PageOutline(2-9)]] 

== Description ==
This style displays the value of [osmwiki:Key:layer] as a coloured underlay. This helps to check, if the correct `layer` value is tagged without the need to select every single way and look at the `layer` value. The following values are allowed: -9, -8, -7, -6, -5, -4, -3, -2, -1, 0, 1, 2, 3, 4, 5, 6, 7, 8, 9. All other values are reported as wrong value. There is a [wiki:Help/Dialog/MapPaint#Stylesettings style setting] to disallow also `layer=0`.

=== Example images ===

'''Example of Layer checker:'''

[[Image(example.png)]]

^(data used for image [osmwww:copyright ©OpenStreetMap contributors] ODbL)^

'''Legend:'''

[[Image(legend.png)]]

== Changelog ==
^(Latest change first)^
==== Version 0.9.x to 1.0.x ====
* change default colours
* add icon
* add style setting to disallow `layer=0`
==== Version 0.9.x ====
* inital version

== Code ==
{{{
#!style type="mapcss"
meta {
    title: "Layer checker";
    version: "1.0.[[revision]]_[[date]]";
    description: "Display of layer values in JOSM map display.";
    icon: "layerchecker.svg";
    author: "Klumbumbus";
    link: "http://josm.openstreetmap.de/wiki/Styles/LayerChecker";
    watch-modified: true;
    /* min-josm-version: "?";  */ /* not sure */
}

meta[lang=de] {
    title: "Ebenenprüfer";
    description: "Anzeige der layer-Werte in der JOSM-Kartenanzeige.";
    link: "http://josm.openstreetmap.de/wiki/De:Styles/LayerChecker";
}

/* create settings */
setting::allow_layer_0 {
    type: boolean;
    label: tr("allow layer=0");
    default: true;
}

/* Changes to the JOSM internal mappaint style elemstyles.mapcss to fit better together with Layer checker */
    /* disable tiger layer */
way["tiger:reviewed"=no]::core_tiger {
    opacity: 0;
}
    /* disable street names */
way[highway] {
    text: none;
}
    /* make bridge and tunnel layer wider */
way[bridge]::core_bridge,
way[tunnel=yes]::core_tunnel {
    width: +6;
}

/* display layer=* */
    /* ways */
way["layer"=~/^(-9|-8|-7|-6|-5|-4|-3)$/]::layer {
    set layer;
    z-index: -3;
    color: layer_minus5#ff0000;
}
way["layer"="-2"]::layer {
    set layer;
    z-index: -2;
    color: layer_minus2#ff7519;
}
way["layer"="-1"]::layer {
    set layer;
    z-index: -1;
    color: layer_minus1#ffff00;
}
way["layer"="0"][setting("allow_layer_0")]::layer {
    set layer;
    z-index: 0;
    color: layer_0#b8b8b8;
}
way["layer"="1"]::layer {
    set layer;
    z-index: 1;
    color: layer_1#00ff00;
}
way["layer"="2"]::layer {
    set layer;
    z-index: 2;
    color: layer_2#00ffff;
}
way["layer"=~/^(9|8|7|6|5|4|3)$/]::layer {
    set layer;
    z-index: 3;
    color: layer_5#9933ff;
}

way.layer::layer {
    opacity: 0.9;
    width: 20;
    major-z-index: 1.9; /* below bridge layer of default style, to see the bridge */
}

    /* nodes */
node["layer"=~/^(-9|-8|-7|-6|-5|-4|-3)$/]::layer {
    set layer;
    z-index: -3;
    symbol-fill-color: layer_minus5#ff0000;
}
node["layer"="-2"]::layer {
    set layer;
    z-index: -2;
    symbol-fill-color: layer_minus2#ff7519;
}
node["layer"="-1"]::layer {
    set layer;
    z-index: -1;
    symbol-fill-color: layer_minus1#ffff00;
}
node["layer"="0"][setting("allow_layer_0")]::layer {
    set layer;
    z-index: 0;
    symbol-fill-color: layer_0#b8b8b8;
}
node["layer"="1"]::layer {
    set layer;
    z-index: 1;
    symbol-fill-color: layer_1#00ff00;
}
node["layer"="2"]::layer {
    set layer;
    z-index: 2;
    symbol-fill-color: layer_2#00ffff;
}
node["layer"=~/^(9|8|7|6|5|4|3)$/]::layer {
    set layer;
    z-index: 3;
    symbol-fill-color: layer_5#9933ff;
}

node.layer::layer {
    symbol-size: 26;
    symbol-shape: circle;
    z-index: -1;
    symbol-fill-opacity: 0.9;
}

/* report wrong value of layer */
way!.layer[layer]::layer {
    color: yellow;
    dashes-background-color: red;
    dashes: 4,24;
    opacity: 1;
    width: 5;
    text: tr("no correct value for layer!");
    text-color: black;
    font-size: 11;
    text-halo-color: red;
    text-halo-radius: 2;
    casing-width: 1;
    casing-color: yellow;
}
node!.layer[layer]::layer {
    symbol-shape: triangle;
    symbol-fill-color: red;
    symbol-size: 30;
    symbol-stroke-color: yellow;
    text: tr("no correct value for layer!");
}
}}}