[core] update mapbox-gl-js submodule

package.json

@@ -14,7 +14,7 @@
   "license": "BSD-2-Clause",
   "dependencies": {
     "nan": "~2.8",
-    "node-pre-gyp": "^0.6.37",
+    "node-pre-gyp": "^0.6.39",
     "npm-run-all": "^4.0.2"
   },
   "devDependencies": {

platform/android/MapboxGLAndroidSDK/src/main/java/com/mapbox/mapboxsdk/style/layers/LineLayer.java

@@ -437,6 +437,32 @@ public void setLinePatternTransition(TransitionOptions options) {
     nativeSetLinePatternTransition(options.getDuration(), options.getDelay());
   }
 
+  /**
+   * Get the LineGradient property
+   *
+   * @return property wrapper value around String
+   */
+  @SuppressWarnings("unchecked")
+  public PropertyValue<String> getLineGradient() {
+    return (PropertyValue<String>) new PropertyValue("line-gradient", nativeGetLineGradient());
+  }
+
+  /**
+   * Defines a gradient with which to color a line feature. Can only be used with GeoJSON sources that specify `"lineMetrics": true`.
+   *
+   * @return int representation of a rgba string color
+   * @throws RuntimeException thrown if property isn't a value
+   */
+  @ColorInt
+  public int getLineGradientAsInt() {
+    PropertyValue<String> value = getLineGradient();
+    if (value.isValue()) {
+      return rgbaToColor(value.getValue());
+    } else {
+      throw new RuntimeException("line-gradient was set as a Function");
+    }
+  }
+
   private native Object nativeGetLineCap();
 
   private native Object nativeGetLineJoin();
@@ -501,6 +527,8 @@ public void setLinePatternTransition(TransitionOptions options) {
 
   private native void nativeSetLinePatternTransition(long duration, long delay);
 
+  private native Object nativeGetLineGradient();
+
   @Override
   protected native void finalize() throws Throwable;
 

platform/android/MapboxGLAndroidSDK/src/main/java/com/mapbox/mapboxsdk/style/layers/PropertyFactory.java

@@ -356,7 +356,7 @@ public static PropertyValue<Expression> lineBlur(Expression expression) {
   }
 
   /**
-   * Specifies the lengths of the alternating dashes and gaps that form the dash pattern. The lengths are later scaled by the line width. To convert a dash length to density-independent pixels, multiply the length by the current line width.
+   * Specifies the lengths of the alternating dashes and gaps that form the dash pattern. The lengths are later scaled by the line width. To convert a dash length to density-independent pixels, multiply the length by the current line width. Note that GeoJSON sources with `lineMetrics: true` specified won't render dashed lines to the expected scale.
    *
    * @param value a Float[] value
    * @return property wrapper around Float[]
@@ -366,7 +366,7 @@ public static PropertyValue<Float[]> lineDasharray(Float[] value) {
   }
 
   /**
-   * Specifies the lengths of the alternating dashes and gaps that form the dash pattern. The lengths are later scaled by the line width. To convert a dash length to density-independent pixels, multiply the length by the current line width.
+   * Specifies the lengths of the alternating dashes and gaps that form the dash pattern. The lengths are later scaled by the line width. To convert a dash length to density-independent pixels, multiply the length by the current line width. Note that GeoJSON sources with `lineMetrics: true` specified won't render dashed lines to the expected scale.
    *
    * @param expression an expression statement
    * @return property wrapper around an expression statement
@@ -395,6 +395,36 @@ public static PropertyValue<Expression> linePattern(Expression expression) {
     return new PaintPropertyValue<>("line-pattern", expression);
   }
 
+  /**
+   * Defines a gradient with which to color a line feature. Can only be used with GeoJSON sources that specify `"lineMetrics": true`.
+   *
+   * @param value a int color value
+   * @return property wrapper around String color
+   */
+  public static PropertyValue<String> lineGradient(@ColorInt int value) {
+    return new PaintPropertyValue<>("line-gradient", colorToRgbaString(value));
+  }
+
+  /**
+   * Defines a gradient with which to color a line feature. Can only be used with GeoJSON sources that specify `"lineMetrics": true`.
+   *
+   * @param value a String value
+   * @return property wrapper around String
+   */
+  public static PropertyValue<String> lineGradient(String value) {
+    return new PaintPropertyValue<>("line-gradient", value);
+  }
+
+  /**
+   * Defines a gradient with which to color a line feature. Can only be used with GeoJSON sources that specify `"lineMetrics": true`.
+   *
+   * @param expression an expression statement
+   * @return property wrapper around an expression statement
+   */
+  public static PropertyValue<Expression> lineGradient(Expression expression) {
+    return new PaintPropertyValue<>("line-gradient", expression);
+  }
+
   /**
    * The opacity at which the icon will be drawn.
    *

platform/android/MapboxGLAndroidSDKTestApp/src/androidTest/java/com/mapbox/mapboxsdk/testapp/style/LineLayerTest.java

@@ -545,4 +545,32 @@ public void testLinePatternAsConstant() {
       assertEquals((String) layer.getLinePattern().getValue(), (String) "pedestrian-polygon");
     });
   }
+
+  @Test
+  public void testLineGradientAsConstant() {
+    validateTestSetup();
+    setupLayer();
+    Timber.i("line-gradient");
+    invoke(mapboxMap, (uiController, mapboxMap) -> {
+      assertNotNull(layer);
+
+      // Set and Get
+      layer.setProperties(lineGradient("rgba(0, 0, 0, 1)"));
+      assertEquals((String) layer.getLineGradient().getValue(), (String) "rgba(0, 0, 0, 1)");
+    });
+  }
+
+  @Test
+  public void testLineGradientAsIntConstant() {
+    validateTestSetup();
+    setupLayer();
+    Timber.i("line-gradient");
+    invoke(mapboxMap, (uiController, mapboxMap) -> {
+      assertNotNull(layer);
+
+      // Set and Get
+      layer.setProperties(lineGradient(Color.RED));
+      assertEquals(layer.getLineGradientAsInt(), Color.RED);
+    });
+  }
 }

platform/android/src/style/layers/line_layer.cpp

@@ -236,6 +236,12 @@ namespace android {
         layer.as<mbgl::style::LineLayer>()->LineLayer::setLinePatternTransition(options);
     }
 
+    jni::Object<jni::ObjectTag> LineLayer::getLineGradient(jni::JNIEnv& env) {
+        using namespace mbgl::android::conversion;
+        Result<jni::jobject*> converted = convert<jni::jobject*>(env, layer.as<mbgl::style::LineLayer>()->LineLayer::getLineGradient());
+        return jni::Object<jni::ObjectTag>(*converted);
+    }
+
 
     jni::Class<LineLayer> LineLayer::javaClass;
 
@@ -287,7 +293,8 @@ namespace android {
             METHOD(&LineLayer::getLineDasharray, "nativeGetLineDasharray"),
             METHOD(&LineLayer::getLinePatternTransition, "nativeGetLinePatternTransition"),
             METHOD(&LineLayer::setLinePatternTransition, "nativeSetLinePatternTransition"),
-            METHOD(&LineLayer::getLinePattern, "nativeGetLinePattern"));
+            METHOD(&LineLayer::getLinePattern, "nativeGetLinePattern"),
+            METHOD(&LineLayer::getLineGradient, "nativeGetLineGradient"));
     }
 
 } // namespace android

platform/android/src/style/layers/line_layer.hpp

@@ -74,6 +74,8 @@ class LineLayer : public Layer {
     jni::Object<jni::ObjectTag> getLinePattern(jni::JNIEnv&);
     void setLinePatternTransition(jni::JNIEnv&, jlong duration, jlong delay);
     jni::Object<TransitionOptions> getLinePatternTransition(jni::JNIEnv&);
+
+    jni::Object<jni::ObjectTag> getLineGradient(jni::JNIEnv&);
     jni::jobject* createJavaPeer(jni::JNIEnv&);
 
 }; // class LineLayer

scripts/generate-shaders.js

@@ -45,6 +45,10 @@ for (const key in shaders) {
     if (key === 'prelude')
         continue;
 
+    // Skip line-gradient until it is ported from gl-js
+    if (key === 'lineGradient')
+        continue;
+
     const shaderName = key.replace(/[A-Z]+/g, (match) => `_${match.toLowerCase()}`);
 
     writeIfModified(path.join(outputPath, `${shaderName}.hpp`), `// NOTE: DO NOT CHANGE THIS FILE. IT IS AUTOMATICALLY GENERATED.

scripts/generate-style-code.js

@@ -168,6 +168,9 @@ const layers = Object.keys(spec.layer.type.values).map((type) => {
   }, []);
 
   const paintProperties = Object.keys(spec[`paint_${type}`]).reduce((memo, name) => {
+    // Skip line-gradient until it is ported from gl-js
+    if (name === 'line-gradient') return memo;
+
     spec[`paint_${type}`][name].name = name;
     memo.push(spec[`paint_${type}`][name]);
     return memo;

src/mbgl/shaders/line.cpp

@@ -31,6 +31,7 @@ uniform vec2 u_gl_units_to_pixels;
 varying vec2 v_normal;
 varying vec2 v_width2;
 varying float v_gamma_scale;
+varying highp float v_linesofar;
 
 
 #ifndef HAS_UNIFORM_u_color
@@ -131,6 +132,8 @@ void main() {
     vec2 a_extrude = a_data.xy - 128.0;
     float a_direction = mod(a_data.z, 4.0) - 1.0;
 
+    v_linesofar = (floor(a_data.z / 4.0) + a_data.w * 64.0) * 2.0;
+
     vec2 pos = a_pos_normal.xy;
 
     // x is 1 if it's a round cap, 0 otherwise