Scalar types by value

5 files changed, 12 insertions, 13 deletions

diff --git a/include/mbgl/style/expression/curve.hpp b/include/mbgl/style/expression/curve.hpp
index d77dd503e6..19a167e3ab 100644
--- a/include/mbgl/style/expression/curve.hpp
+++ b/include/mbgl/style/expression/curve.hpp
@@ -16,7 +16,7 @@ namespace expression {
 
 class StepInterpolator {
 public:
-    double interpolationFactor(const Range<double>&, const double&) const {
+    double interpolationFactor(const Range<double>&, const double) const {
         return 0;
     }
     
@@ -28,7 +28,7 @@ public:
 
     double base;
     
-    double interpolationFactor(const Range<double>& inputLevels, const double& input) const {
+    double interpolationFactor(const Range<double>& inputLevels, const double input) const {
         return util::interpolationFactor(base,
                                          Range<float> {
                                             static_cast<float>(inputLevels.min),
@@ -42,7 +42,7 @@ class CubicBezierInterpolator {
 public:
     CubicBezierInterpolator(double x1_, double y1_, double x2_, double y2_) : ub(x1_, y1_, x2_, y2_) {}
     
-    double interpolationFactor(const Range<double>& inputLevels, const double& input) const {
+    double interpolationFactor(const Range<double>& inputLevels, const double input) const {
         return ub.solve(input / (inputLevels.max - inputLevels.min), 1e-6);
     }
     
@@ -160,7 +160,7 @@ public:
         };
     }
     
-    double interpolationFactor(const Range<double>& inputLevels, const double& inputValue) const {
+    double interpolationFactor(const Range<double>& inputLevels, const double inputValue) const {
         return interpolator.match(
             [&](const auto& interp) { return interp.interpolationFactor(inputLevels, inputValue); }
         );
@@ -168,7 +168,7 @@ public:
     
 private:
     template <typename OutputType = T>
-    static EvaluationResult interpolate(const Range<Value>&, const double&,
+    static EvaluationResult interpolate(const Range<Value>&, const double,
                                         typename std::enable_if<!util::Interpolatable<OutputType>::value>::type* = nullptr) {
         // Assume that Curve::evaluate() will always short circuit due to
         // interpolationFactor always returning 0.
@@ -177,7 +177,7 @@ private:
     }
     
     template <typename OutputType = T>
-    static EvaluationResult interpolate(const Range<Value>& outputs, const double& t,
+    static EvaluationResult interpolate(const Range<Value>& outputs, const double t,
                                         typename std::enable_if<util::Interpolatable<OutputType>::value>::type* = nullptr) {
         optional<T> lower = fromExpressionValue<T>(outputs.min);
         if (!lower) {
diff --git a/include/mbgl/style/expression/value.hpp b/include/mbgl/style/expression/value.hpp
index 454844994f..c92d0c4e19 100644
--- a/include/mbgl/style/expression/value.hpp
+++ b/include/mbgl/style/expression/value.hpp
@@ -102,7 +102,7 @@ template <>
 struct ValueConverter<float> {
     using ExpressionType = double;
     static type::Type expressionType() { return type::Number; }
-    static Value toExpressionValue(const float& value);
+    static Value toExpressionValue(const float value);
     static optional<float> fromExpressionValue(const Value& value);
 };
 
diff --git a/include/mbgl/style/function/camera_function.hpp b/include/mbgl/style/function/camera_function.hpp
index cf43940a13..b1d31d1216 100644
--- a/include/mbgl/style/function/camera_function.hpp
+++ b/include/mbgl/style/function/camera_function.hpp
@@ -52,7 +52,7 @@ public:
         return T();
     }
     
-    float interpolationFactor(const Range<float>& inputLevels, const float& inputValue) const {
+    float interpolationFactor(const Range<float>& inputLevels, const float inputValue) const {
         return zoomCurve->interpolationFactor(Range<double> { inputLevels.min, inputLevels.max }, inputValue);
     }
     
diff --git a/include/mbgl/style/function/composite_function.hpp b/include/mbgl/style/function/composite_function.hpp
index 9aa72ec65d..1985153a12 100644
--- a/include/mbgl/style/function/composite_function.hpp
+++ b/include/mbgl/style/function/composite_function.hpp
@@ -87,7 +87,7 @@ public:
         return finalDefaultValue;
     }
     
-    float interpolationFactor(const Range<float>& inputLevels, const float& inputValue) const {
+    float interpolationFactor(const Range<float>& inputLevels, const float inputValue) const {
         return zoomCurve->interpolationFactor(Range<double> { inputLevels.min, inputLevels.max }, inputValue);
     }
     
diff --git a/src/mbgl/style/expression/value.cpp b/src/mbgl/style/expression/value.cpp
index 6150e5e4bb..372d1db5e9 100644
--- a/src/mbgl/style/expression/value.cpp
+++ b/src/mbgl/style/expression/value.cpp
@@ -91,9 +91,9 @@ struct FromMBGLValue {
     }
     
     Value operator()(const std::string& s) { return s; }
-    Value operator()(const bool& b) { return b; }
+    Value operator()(const bool b) { return b; }
     Value operator()(const NullValue) { return Null; }
-    Value operator()(const double& v) { return v; }
+    Value operator()(const double v) { return v; }
     Value operator()(const uint64_t& v) {
         return static_cast<double>(v);
     }
@@ -106,8 +106,7 @@ Value ValueConverter<mbgl::Value>::toExpressionValue(const mbgl::Value& value) {
     return mbgl::Value::visit(value, FromMBGLValue());
 }
 
-
-Value ValueConverter<float>::toExpressionValue(const float& value) {
+Value ValueConverter<float>::toExpressionValue(const float value) {
     return static_cast<double>(value);
 }