[core] Rationalize naming for style-related code

1 files changed, 116 insertions, 0 deletions

diff --git a/src/mbgl/style/layers/line_layer_impl.cpp b/src/mbgl/style/layers/line_layer_impl.cpp
new file mode 100644
index 0000000000..b7ee9dc5bf
--- /dev/null
+++ b/src/mbgl/style/layers/line_layer_impl.cpp
@@ -0,0 +1,116 @@
+#include <mbgl/style/layers/line_layer_impl.hpp>
+#include <mbgl/style/bucket_parameters.hpp>
+#include <mbgl/renderer/line_bucket.hpp>
+#include <mbgl/geometry/feature_index.hpp>
+#include <mbgl/util/math.hpp>
+#include <mbgl/util/intersection_tests.hpp>
+
+namespace mbgl {
+namespace style {
+
+void LineLayer::Impl::parseLayout(const JSValue& value) {
+    layout.parse(value);
+}
+
+void LineLayer::Impl::parsePaints(const JSValue& layer) {
+    paint.parse(layer);
+}
+
+void LineLayer::Impl::cascade(const CascadeParameters& parameters) {
+    paint.cascade(parameters);
+}
+
+bool LineLayer::Impl::recalculate(const CalculationParameters& parameters) {
+    // for scaling dasharrays
+    CalculationParameters dashArrayParams = parameters;
+    dashArrayParams.z = std::floor(dashArrayParams.z);
+    paint.lineWidth.calculate(dashArrayParams);
+    dashLineWidth = paint.lineWidth;
+
+    bool hasTransitions = paint.recalculate(parameters);
+
+    passes = (paint.lineOpacity > 0 && paint.lineColor.value[3] > 0 && paint.lineWidth > 0)
+        ? RenderPass::Translucent : RenderPass::None;
+
+    return hasTransitions;
+}
+
+std::unique_ptr<Bucket> LineLayer::Impl::createBucket(BucketParameters& parameters) const {
+    auto bucket = std::make_unique<LineBucket>(parameters.tileID.overscaleFactor());
+
+    bucket->layout = layout;
+    bucket->layout.recalculate(CalculationParameters(parameters.tileID.overscaledZ));
+
+    auto& name = bucketName();
+    parameters.eachFilteredFeature(filter, [&] (const auto& feature, std::size_t index, const std::string& layerName) {
+        auto geometries = feature.getGeometries();
+        bucket->addGeometry(geometries);
+        parameters.featureIndex.insert(geometries, index, layerName, name);
+    });
+
+    return std::move(bucket);
+}
+
+float LineLayer::Impl::getLineWidth() const {
+    if (paint.lineGapWidth > 0) {
+        return paint.lineGapWidth + 2 * paint.lineWidth;
+    } else {
+        return paint.lineWidth;
+    }
+}
+
+optional<GeometryCollection> offsetLine(const GeometryCollection& rings, const double offset) {
+    if (offset == 0) return {};
+
+    GeometryCollection newRings;
+    Point<double> zero(0, 0);
+    for (const auto& ring : rings) {
+        newRings.emplace_back();
+        auto& newRing = newRings.back();
+
+        for (auto i = ring.begin(); i != ring.end(); i++) {
+            auto& p = *i;
+
+            Point<double> aToB = i == ring.begin() ?
+                zero :
+                util::perp(util::unit(convertPoint<double>(p - *(i - 1))));
+            Point<double> bToC = i + 1 == ring.end() ?
+                zero :
+                util::perp(util::unit(convertPoint<double>(*(i + 1) - p)));
+            Point<double> extrude = util::unit(aToB + bToC);
+
+            const double cosHalfAngle = extrude.x * bToC.x + extrude.y * bToC.y;
+            extrude *= (1.0 / cosHalfAngle);
+
+            newRing.push_back(convertPoint<int16_t>(extrude * offset) + p);
+        }
+    }
+
+    return newRings;
+}
+
+float LineLayer::Impl::getQueryRadius() const {
+    const std::array<float, 2>& translate = paint.lineTranslate;
+    return getLineWidth() / 2.0 + std::abs(paint.lineOffset) + util::length(translate[0], translate[1]);
+}
+
+bool LineLayer::Impl::queryIntersectsGeometry(
+        const GeometryCollection& queryGeometry,
+        const GeometryCollection& geometry,
+        const float bearing,
+        const float pixelsToTileUnits) const {
+
+    const float halfWidth = getLineWidth() / 2.0 * pixelsToTileUnits;
+
+    auto translatedQueryGeometry = FeatureIndex::translateQueryGeometry(
+            queryGeometry, paint.lineTranslate, paint.lineTranslateAnchor, bearing, pixelsToTileUnits);
+    auto offsetGeometry = offsetLine(geometry, paint.lineOffset * pixelsToTileUnits);
+
+    return util::multiPolygonIntersectsBufferedMultiLine(
+            translatedQueryGeometry.value_or(queryGeometry),
+            offsetGeometry.value_or(geometry),
+            halfWidth);
+}
+
+} // namespace style
+} // namespace mbgl