1 files changed, 16 insertions, 7 deletions
diff --git a/include/mbgl/style/function/camera_function.hpp b/include/mbgl/style/function/camera_function.hpp
index c44002e8c1..721d3083e1 100644
--- a/include/mbgl/style/function/camera_function.hpp
+++ b/include/mbgl/style/function/camera_function.hpp
@@ -1,7 +1,9 @@
 #pragma once
 
 #include <mbgl/style/expression/expression.hpp>
-#include <mbgl/style/expression/curve.hpp>
+#include <mbgl/style/expression/interpolate.hpp>
+#include <mbgl/style/expression/step.hpp>
+#include <mbgl/style/expression/find_zoom_curve.hpp>
 #include <mbgl/style/expression/value.hpp>
 #include <mbgl/style/expression/is_constant.hpp>
 #include <mbgl/style/function/convert.hpp>
@@ -17,7 +19,7 @@ namespace style {
 template <class T>
 class CameraFunction {
 public:
-    using Curve = expression::Curve<typename expression::ValueConverter<T>::ExpressionType>;
+    using ExpressionType = typename expression::ValueConverter<T>::ExpressionType;
     
     using Stops = std::conditional_t<
         util::Interpolatable<T>::value,
@@ -29,7 +31,7 @@ public:
     
     CameraFunction(std::unique_ptr<expression::Expression> expression_)
         : expression(std::move(expression_)),
-          zoomCurve(*Curve::findZoomCurve(expression.get()))
+          zoomCurve(*expression::findZoomCurve<ExpressionType>(expression.get()))
     {
         assert(!isZoomConstant(expression.get()));
         assert(isFeatureConstant(expression.get()));
@@ -40,7 +42,7 @@ public:
           expression(stops.match([&] (const auto& s) {
             return expression::Convert::toExpression(s);
           })),
-          zoomCurve(*Curve::findZoomCurve(expression.get()))
+          zoomCurve(*expression::findZoomCurve<ExpressionType>(expression.get()))
     {}
 
     T evaluate(float zoom) const {
@@ -53,11 +55,18 @@ public:
     }
     
     float interpolationFactor(const Range<float>& inputLevels, const float inputValue) const {
-        return zoomCurve->interpolationFactor(Range<double> { inputLevels.min, inputLevels.max }, inputValue);
+        return zoomCurve.match(
+            [&](expression::Interpolate<ExpressionType>* z) {
+                return z->interpolationFactor(Range<double> { inputLevels.min, inputLevels.max }, inputValue);
+            },
+            [&](expression::Step*) { return 0.0f; }
+        );
     }
     
     Range<float> getCoveringStops(const float lower, const float upper) const {
-        return zoomCurve->getCoveringStops(lower, upper);
+        return zoomCurve.match(
+            [&](auto z) { return z->getCoveringStops(lower, upper); }
+        );
     }
     
     friend bool operator==(const CameraFunction& lhs,
@@ -72,7 +81,7 @@ public:
 
 private:
     std::shared_ptr<expression::Expression> expression;
-    const Curve* zoomCurve;
+    const variant<expression::Interpolate<ExpressionType>*, expression::Step*> zoomCurve;
 };
 
 } // namespace style