Drop paint classes

API.md

@@ -1,4 +1,51 @@
 
+### `declassStyle(style, classes)`
+
+Returns a new style with the given 'paint classes' merged into each layer's
+main `paint` definiton, and with all `paint.*` properties removed.
+
+
+### Parameters
+
+| parameter | type              | description                                    |
+| --------- | ----------------- | ---------------------------------------------- |
+| `style`   | Object            | A style JSON object.                           |
+| `classes` | Array\.\<string\> | An array of paint classes to apply, in order.  |
+
+
+### Example
+
+```js
+var declass = require('mapbox-gl-style-spec/lib/declass')
+var baseStyle = { ... style with a 'paint.night' property in some layers ... }
+var nightStyle = declass(baseStyle, ['night'])
+// nightStyle now has each layer's `paint.night` properties merged in to the
+// main `paint` property.
+```
+
+
+### `derefLayers(layers)`
+
+Given an array of layers, some of which may contain `ref` properties
+whose value is the `id` of another property, return a new array where
+such layers have been augmented with the 'type', 'source', etc. properties
+from the parent layer, and the `ref` property has been removed.
+
+The input is not modified. The output may contain references to portions
+of the input.
+
+
+### Parameters
+
+| parameter | type             | description |
+| --------- | ---------------- | ----------- |
+| `layers`  | Array\.\<Layer\> |             |
+
+
+
+**Returns** `Array.<Layer>`, 
+
+
 ### `diffStyles([before], after)`
 
 Diff two stylesheet
@@ -60,6 +107,29 @@ fs.writeFileSync('./dest.min.json', format(style, 0));
 **Returns** `string`, stringified formatted JSON
 
 
+### `groupByLayout(layers)`
+
+Given an array of layers, return an array of arrays of layers where all
+layers in each group have identical layout-affecting properties. These
+are the properties that were formerly used by explicit `ref` mechanism
+for layers: 'type', 'source', 'source-layer', 'minzoom', 'maxzoom',
+'filter', and 'layout'.
+
+The input is not modified. The output layers are references to the
+input layers.
+
+
+### Parameters
+
+| parameter | type             | description |
+| --------- | ---------------- | ----------- |
+| `layers`  | Array\.\<Layer\> |             |
+
+
+
+**Returns** `Array.<Array.<Layer>>`, 
+
+
 ### `migrate(style)`
 
 Migrate a Mapbox GL Style to the latest version.

docs/_generate/index.html

@@ -628,9 +628,6 @@ <h2><a href='#layers' title='link to layers'>Layers</a></h2>
       <p>
         <em>Paint properties</em> are applied later in the rendering process. A layer that shares layout properties with another
         layer can have independent paint properties. Paint properties appear in the layer's <code>"paint"</code> object.
-        Layers can also have class-specific paint properties, which are applied only when the map has a certain class
-        name set. For example, a layer with a <code>"paint.night"</code> property would have those properties applied
-        when the map has the <code>"night"</code> class set.
       </p>
       <p class='space-bottom4 quiet small'>Key:
         <a class='icon smooth-ramp quiet micro space-right inline' href='#function' title='Supports interpolated functions'>supports interpolated functions</a>

lib/declass.js

@@ -2,14 +2,23 @@
 
 var extend = require('./util/extend');
 
+module.exports = declassStyle;
+
 /**
  * Returns a new style with the given 'paint classes' merged into each layer's
- * main `paint` definiton.
+ * main `paint` definiton, and with all `paint.*` properties removed.
  *
  * @param {Object} style A style JSON object.
  * @param {Array<string>} classes An array of paint classes to apply, in order.
+ *
+ * @example
+ * var declass = require('mapbox-gl-style-spec/lib/declass')
+ * var baseStyle = { ... style with a 'paint.night' property in some layers ... }
+ * var nightStyle = declass(baseStyle, ['night'])
+ * // nightStyle now has each layer's `paint.night` properties merged in to the
+ * // main `paint` property.
  */
-module.exports = function declassStyle(style, classes) {
+function declassStyle(style, classes) {
     return extend({}, style, {
         layers: style.layers.map(function (layer) {
             var result = classes.reduce(declassLayer, layer);
@@ -24,7 +33,7 @@ module.exports = function declassStyle(style, classes) {
             return result;
         })
     });
-};
+}
 
 function declassLayer(layer, klass) {
     return extend({}, layer, {

lib/deref.js

@@ -20,6 +20,8 @@ function deref(layer, parent) {
     return result;
 }
 
+module.exports = derefLayers;
+
 /**
  * Given an array of layers, some of which may contain `ref` properties
  * whose value is the `id` of another property, return a new array where
@@ -32,7 +34,7 @@ function deref(layer, parent) {
  * @param {Array<Layer>} layers
  * @returns {Array<Layer>}
  */
-module.exports = function (layers) {
+function derefLayers(layers) {
     layers = layers.slice();
 
     var map = Object.create(null), i;
@@ -47,4 +49,4 @@ module.exports = function (layers) {
     }
 
     return layers;
-};
+}

lib/group_by_layout.js

@@ -9,6 +9,8 @@ function key(layer) {
     }));
 }
 
+module.exports = groupByLayout;
+
 /**
  * Given an array of layers, return an array of arrays of layers where all
  * layers in each group have identical layout-affecting properties. These
@@ -22,7 +24,7 @@ function key(layer) {
  * @param {Array<Layer>} layers
  * @returns {Array<Array<Layer>>}
  */
-module.exports = function (layers) {
+function groupByLayout(layers) {
     var groups = {}, i, k;
 
     for (i = 0; i < layers.length; i++) {
@@ -41,4 +43,4 @@ module.exports = function (layers) {
     }
 
     return result;
-};
+}

migrations/v9.js

@@ -0,0 +1,27 @@
+'use strict';
+
+var deref = require('../lib/deref');
+
+function eachLayer(style, callback) {
+    for (var k in style.layers) {
+        callback(style.layers[k]);
+    }
+}
+
+module.exports = function(style) {
+    style.version = 9;
+
+    // remove user-specified refs
+    style.layers = deref(style.layers);
+
+    // remove class-specific paint properties
+    eachLayer(style, function (layer) {
+        for (var k in layer) {
+            if (/paint\..*/.test(k)) {
+                delete layer[k];
+            }
+        }
+    });
+
+    return style;
+};

reference/v8.json

@@ -337,7 +337,7 @@
     },
     "paint.*": {
       "type": "paint",
-      "doc": "Class-specific paint properties for this layer. The class name is the part after the first dot."
+      "doc": "[Deprecated] Class-specific paint properties for this layer. The class name is the part after the first dot. Note: class-specific paint properties are deprecated and will be removed in the next version of this spec."
     }
   },
   "layout": [

test/migrations/v9.js

@@ -0,0 +1,78 @@
+'use strict';
+
+var t = require('tape'),
+    migrate = require('../../migrations/v9');
+
+t('deref layers', function (t) {
+    var input = {
+        version: 8,
+        sources: {
+            a: { type: 'vector', tiles: [ 'http://dev/null' ] }
+        },
+        layers: [{
+            id: 'parent',
+            source: 'a',
+            'source-layer': 'x',
+            type: 'fill'
+        }, {
+            id: 'child',
+            ref: 'parent'
+        }]
+    };
+
+    t.deepEqual(migrate(input), {
+        version: 9,
+        sources: {
+            a: { type: 'vector', tiles: [ 'http://dev/null' ] }
+        },
+        layers: [{
+            id: 'parent',
+            source: 'a',
+            'source-layer': 'x',
+            type: 'fill'
+        }, {
+            id: 'child',
+            source: 'a',
+            'source-layer': 'x',
+            type: 'fill'
+        }]
+    });
+
+    t.end();
+});
+
+t('declass style', function (t) {
+    var input = {
+        version: 8,
+        sources: {
+            a: { type: 'vector', tiles: [ 'http://dev/null' ] }
+        },
+        layers: [{
+            id: 'a',
+            source: 'a',
+            type: 'fill',
+            paint: {},
+            'paint.right': {
+                'fill-color': 'red'
+            },
+            'paint.left': {
+                'fill-color': 'blue'
+            }
+        }]
+    };
+
+    t.deepEqual(migrate(input), {
+        version: 9,
+        sources: {
+            a: { type: 'vector', tiles: [ 'http://dev/null' ] }
+        },
+        layers: [{
+            id: 'a',
+            source: 'a',
+            type: 'fill',
+            paint: {}
+        }]
+    });
+
+    t.end();
+});