[core] implement property functions for line-join

9 files changed, 31 insertions, 35 deletions

diff --git a/include/mbgl/style/conversion/make_property_setters.hpp b/include/mbgl/style/conversion/make_property_setters.hpp
index f29d5f5b6f..f5d7f1874b 100644
--- a/include/mbgl/style/conversion/make_property_setters.hpp
+++ b/include/mbgl/style/conversion/make_property_setters.hpp
@@ -26,7 +26,7 @@ auto makeLayoutPropertySetters() {
 
 
     result["line-cap"] = &setProperty<V, LineLayer, PropertyValue<LineCapType>, &LineLayer::setLineCap>;
-    result["line-join"] = &setProperty<V, LineLayer, PropertyValue<LineJoinType>, &LineLayer::setLineJoin>;
+    result["line-join"] = &setProperty<V, LineLayer, DataDrivenPropertyValue<LineJoinType>, &LineLayer::setLineJoin>;
     result["line-miter-limit"] = &setProperty<V, LineLayer, PropertyValue<float>, &LineLayer::setLineMiterLimit>;
     result["line-round-limit"] = &setProperty<V, LineLayer, PropertyValue<float>, &LineLayer::setLineRoundLimit>;
 
diff --git a/include/mbgl/style/layers/line_layer.hpp b/include/mbgl/style/layers/line_layer.hpp
index 0b49690fd8..4519296323 100644
--- a/include/mbgl/style/layers/line_layer.hpp
+++ b/include/mbgl/style/layers/line_layer.hpp
@@ -42,9 +42,9 @@ public:
     PropertyValue<LineCapType> getLineCap() const;
     void setLineCap(PropertyValue<LineCapType>);
 
-    static PropertyValue<LineJoinType> getDefaultLineJoin();
-    PropertyValue<LineJoinType> getLineJoin() const;
-    void setLineJoin(PropertyValue<LineJoinType>);
+    static DataDrivenPropertyValue<LineJoinType> getDefaultLineJoin();
+    DataDrivenPropertyValue<LineJoinType> getLineJoin() const;
+    void setLineJoin(DataDrivenPropertyValue<LineJoinType>);
 
     static PropertyValue<float> getDefaultLineMiterLimit();
     PropertyValue<float> getLineMiterLimit() const;
diff --git a/src/mbgl/renderer/buckets/line_bucket.cpp b/src/mbgl/renderer/buckets/line_bucket.cpp
index d1771d484a..194b012eee 100644
--- a/src/mbgl/renderer/buckets/line_bucket.cpp
+++ b/src/mbgl/renderer/buckets/line_bucket.cpp
@@ -15,7 +15,8 @@ LineBucket::LineBucket(const BucketParameters& parameters,
                        const std::vector<const RenderLayer*>& layers,
                        const style::LineLayoutProperties::Unevaluated& layout_)
     : layout(layout_.evaluate(PropertyEvaluationParameters(parameters.tileID.overscaledZ))),
-      overscaling(parameters.tileID.overscaleFactor()) {
+      overscaling(parameters.tileID.overscaleFactor()),
+      zoom(parameters.tileID.overscaledZ) {
     for (const auto& layer : layers) {
         paintPropertyBinders.emplace(
             std::piecewise_construct,
@@ -29,7 +30,7 @@ LineBucket::LineBucket(const BucketParameters& parameters,
 void LineBucket::addFeature(const GeometryTileFeature& feature,
                             const GeometryCollection& geometryCollection) {
     for (auto& line : geometryCollection) {
-        addGeometry(line, feature.getType());
+        addGeometry(line, feature);
     }
 
     for (auto& pair : paintPropertyBinders) {
@@ -62,7 +63,8 @@ const float LINE_DISTANCE_SCALE = 1.0 / 2.0;
 // The maximum line distance, in tile units, that fits in the buffer.
 const float MAX_LINE_DISTANCE = std::pow(2, LINE_DISTANCE_BUFFER_BITS) / LINE_DISTANCE_SCALE;
 
-void LineBucket::addGeometry(const GeometryCoordinates& coordinates, FeatureType type) {
+void LineBucket::addGeometry(const GeometryCoordinates& coordinates, const GeometryTileFeature& feature) {
+    const FeatureType type = feature.getType();
     const std::size_t len = [&coordinates] {
         std::size_t l = coordinates.size();
         // If the line has duplicate vertices at the end, adjust length to remove them.
@@ -86,7 +88,9 @@ void LineBucket::addGeometry(const GeometryCoordinates& coordinates, FeatureType
         return;
     }
 
-    const float miterLimit = layout.get<LineJoin>() == LineJoinType::Bevel ? 1.05f : float(layout.get<LineMiterLimit>());
+    const LineJoinType joinType = layout.evaluate<LineJoin>(zoom, feature);
+
+    const float miterLimit = joinType == LineJoinType::Bevel ? 1.05f : float(layout.get<LineMiterLimit>());
 
     const double sharpCornerOffset = SHARP_CORNER_OFFSET * (float(util::EXTENT) / (util::tileSize * overscaling));
 
@@ -193,7 +197,7 @@ void LineBucket::addGeometry(const GeometryCoordinates& coordinates, FeatureType
 
         // The join if a middle vertex, otherwise the cap
         const bool middleVertex = prevCoordinate && nextCoordinate;
-        LineJoinType currentJoin = layout.get<LineJoin>();
+        LineJoinType currentJoin = joinType;
         const LineCapType currentCap = nextCoordinate ? beginCap : endCap;
 
         if (middleVertex) {
diff --git a/src/mbgl/renderer/buckets/line_bucket.hpp b/src/mbgl/renderer/buckets/line_bucket.hpp
index 8ef25b02ec..4fb77c377e 100644
--- a/src/mbgl/renderer/buckets/line_bucket.hpp
+++ b/src/mbgl/renderer/buckets/line_bucket.hpp
@@ -41,7 +41,7 @@ public:
     std::map<std::string, LineProgram::PaintPropertyBinders> paintPropertyBinders;
 
 private:
-    void addGeometry(const GeometryCoordinates&, FeatureType);
+    void addGeometry(const GeometryCoordinates&, const GeometryTileFeature&);
 
     struct TriangleElement {
         TriangleElement(uint16_t a_, uint16_t b_, uint16_t c_) : a(a_), b(b_), c(c_) {}
@@ -59,6 +59,7 @@ private:
     std::ptrdiff_t e3;
 
     const uint32_t overscaling;
+    const float zoom;
 
     float getLineWidth(const RenderLineLayer& layer) const;
 };
diff --git a/src/mbgl/shaders/preludes.cpp b/src/mbgl/shaders/preludes.cpp
index 95fa624e8d..feb185a684 100644
--- a/src/mbgl/shaders/preludes.cpp
+++ b/src/mbgl/shaders/preludes.cpp
@@ -24,25 +24,6 @@ precision highp float;
 
 #endif
 
-float evaluate_zoom_function_1(const vec4 values, const float t) {
-    if (t < 1.0) {
-        return mix(values[0], values[1], t);
-    } else if (t < 2.0) {
-        return mix(values[1], values[2], t - 1.0);
-    } else {
-        return mix(values[2], values[3], t - 2.0);
-    }
-}
-vec4 evaluate_zoom_function_4(const vec4 value0, const vec4 value1, const vec4 value2, const vec4 value3, const float t) {
-    if (t < 1.0) {
-        return mix(value0, value1, t);
-    } else if (t < 2.0) {
-        return mix(value1, value2, t - 1.0);
-    } else {
-        return mix(value2, value3, t - 2.0);
-    }
-}
-
 // Unpack a pair of values that have been packed into a single float.
 // The packed values are assumed to be 8-bit unsigned integers, and are
 // packed like so:
@@ -54,8 +35,8 @@ vec2 unpack_float(const float packedValue) {
 }
 
 
-// To minimize the number of attributes needed in the mapbox-gl-native shaders,
-// we encode a 4-component color into a pair of floats (i.e. a vec2) as follows:
+// To minimize the number of attributes needed, we encode a 4-component
+// color into a pair of floats (i.e. a vec2) as follows:
 // [ floor(color.r * 255) * 256 + color.g * 255,
 //   floor(color.b * 255) * 256 + color.g * 255 ]
 vec4 decode_color(const vec2 encodedColor) {
diff --git a/src/mbgl/style/function/categorical_stops.cpp b/src/mbgl/style/function/categorical_stops.cpp
index 2984c3832f..8b5dc65fe9 100644
--- a/src/mbgl/style/function/categorical_stops.cpp
+++ b/src/mbgl/style/function/categorical_stops.cpp
@@ -33,6 +33,7 @@ template class CategoricalStops<Color>;
 template class CategoricalStops<std::array<float, 2>>;
 template class CategoricalStops<std::string>;
 template class CategoricalStops<TextTransformType>;
+template class CategoricalStops<LineJoinType>;
 
 } // namespace style
 } // namespace mbgl
diff --git a/src/mbgl/style/function/identity_stops.cpp b/src/mbgl/style/function/identity_stops.cpp
index 0c6891eac5..1bb14f077f 100644
--- a/src/mbgl/style/function/identity_stops.cpp
+++ b/src/mbgl/style/function/identity_stops.cpp
@@ -41,6 +41,15 @@ optional<TextTransformType> IdentityStops<TextTransformType>::evaluate(const Val
 }
 
 template <>
+optional<LineJoinType> IdentityStops<LineJoinType>::evaluate(const Value& value) const {
+    if (!value.is<std::string>()) {
+        return {};
+    }
+
+    return Enum<LineJoinType>::toEnum(value.get<std::string>());
+}
+
+template <>
 optional<std::array<float, 2>> IdentityStops<std::array<float, 2>>::evaluate(const Value& value) const {
     if (!value.is<std::vector<Value>>()) {
         return {};
diff --git a/src/mbgl/style/layers/line_layer.cpp b/src/mbgl/style/layers/line_layer.cpp
index 6fbdf19568..1c7f0d28ee 100644
--- a/src/mbgl/style/layers/line_layer.cpp
+++ b/src/mbgl/style/layers/line_layer.cpp
@@ -108,15 +108,15 @@ void LineLayer::setLineCap(PropertyValue<LineCapType> value) {
     baseImpl = std::move(impl_);
     observer->onLayerChanged(*this);
 }
-PropertyValue<LineJoinType> LineLayer::getDefaultLineJoin() {
+DataDrivenPropertyValue<LineJoinType> LineLayer::getDefaultLineJoin() {
     return LineJoin::defaultValue();
 }
 
-PropertyValue<LineJoinType> LineLayer::getLineJoin() const {
+DataDrivenPropertyValue<LineJoinType> LineLayer::getLineJoin() const {
     return impl().layout.get<LineJoin>();
 }
 
-void LineLayer::setLineJoin(PropertyValue<LineJoinType> value) {
+void LineLayer::setLineJoin(DataDrivenPropertyValue<LineJoinType> value) {
     if (value == getLineJoin())
         return;
     auto impl_ = mutableImpl();
diff --git a/src/mbgl/style/layers/line_layer_properties.hpp b/src/mbgl/style/layers/line_layer_properties.hpp
index b2c7f3199c..aeaf51698a 100644
--- a/src/mbgl/style/layers/line_layer_properties.hpp
+++ b/src/mbgl/style/layers/line_layer_properties.hpp
@@ -17,7 +17,7 @@ struct LineCap : LayoutProperty<LineCapType> {
     static LineCapType defaultValue() { return LineCapType::Butt; }
 };
 
-struct LineJoin : LayoutProperty<LineJoinType> {
+struct LineJoin : DataDrivenLayoutProperty<LineJoinType> {
     static constexpr const char * key = "line-join";
     static LineJoinType defaultValue() { return LineJoinType::Miter; }
 };