[core] UnitBezier ctor is now constexpr

include/mbgl/util/unitbezier.hpp

@@ -31,32 +31,31 @@ namespace mbgl {
 namespace util {
 
 struct UnitBezier {
-    UnitBezier(double p1x, double p1y, double p2x, double p2y) {
-        // Calculate the polynomial coefficients, implicit first and last control points are (0,0) and (1,1).
-        cx = 3.0 * p1x;
-        bx = 3.0 * (p2x - p1x) - cx;
-        ax = 1.0 - cx - bx;
-
-        cy = 3.0 * p1y;
-        by = 3.0 * (p2y - p1y) - cy;
-        ay = 1.0 - cy - by;
+    // Calculate the polynomial coefficients, implicit first and last control points are (0,0) and (1,1).
+    constexpr UnitBezier(double p1x, double p1y, double p2x, double p2y)
+        : cx(3.0 * p1x)
+        , bx(3.0 * (p2x - p1x) - cx)
+        , ax(1.0 - cx - bx)
+        , cy(3.0 * p1y)
+        , by(3.0 * (p2y - p1y) - cy)
+        , ay(1.0 - cy - by) {
     }
 
-    double sampleCurveX(double t) {
+    double sampleCurveX(double t) const {
         // `ax t^3 + bx t^2 + cx t' expanded using Horner's rule.
         return ((ax * t + bx) * t + cx) * t;
     }
 
-    double sampleCurveY(double t) {
+    double sampleCurveY(double t) const {
         return ((ay * t + by) * t + cy) * t;
     }
 
-    double sampleCurveDerivativeX(double t) {
+    double sampleCurveDerivativeX(double t) const {
         return (3.0 * ax * t + 2.0 * bx) * t + cx;
     }
 
     // Given an x value, find a parametric value it came from.
-    double solveCurveX(double x, double epsilon) {
+    double solveCurveX(double x, double epsilon) const {
         double t0;
         double t1;
         double t2;
@@ -100,18 +99,18 @@ struct UnitBezier {
         return t2;
     }
 
-    double solve(double x, double epsilon) {
+    double solve(double x, double epsilon) const {
         return sampleCurveY(solveCurveX(x, epsilon));
     }
 
 private:
-    double ax;
-    double bx;
-    double cx;
+    const double cx;
+    const double bx;
+    const double ax;
 
-    double ay;
-    double by;
-    double cy;
+    const double cy;
+    const double by;
+    const double ay;
 };
 
 } // namespace util

platform/android/src/jni.cpp

@@ -889,7 +889,7 @@ void nativeSetVisibleCoordinateBounds(JNIEnv *env, jni::jobject* obj, jlong nati
     if (duration > 0) {
         animationOptions.duration.emplace(mbgl::Milliseconds(duration));
         // equivalent to kCAMediaTimingFunctionDefault in iOS
-        animationOptions.easing = mbgl::util::UnitBezier(0.25, 0.1, 0.25, 0.1);
+        animationOptions.easing.emplace(mbgl::util::UnitBezier { 0.25, 0.1, 0.25, 0.1 });
     }
 
     nativeMapView->getMap().easeTo(cameraOptions, animationOptions);
@@ -1054,7 +1054,7 @@ void nativeEaseTo(JNIEnv *env, jni::jobject* obj, jlong nativeMapViewPtr, jdoubl
 
     if (!easing) {
        // add a linear interpolator instead of easing
-       animationOptions.easing = mbgl::util::UnitBezier(0, 0, 1, 1);
+       animationOptions.easing.emplace(mbgl::util::UnitBezier { 0, 0, 1, 1 });
     }
 
     nativeMapView->getMap().easeTo(cameraOptions, animationOptions);

platform/ios/src/MGLMapView.mm

@@ -2196,8 +2196,8 @@ mbgl::Duration MGLDurationInSeconds(NSTimeInterval duration)
     mbgl::AnimationOptions animationOptions;
     if (duration)
     {
-        animationOptions.duration = MGLDurationInSeconds(duration);
-        animationOptions.easing = MGLUnitBezierForMediaTimingFunction(function);
+        animationOptions.duration.emplace(MGLDurationInSeconds(duration));
+        animationOptions.easing.emplace(MGLUnitBezierForMediaTimingFunction(function));
     }
     if (completion)
     {
@@ -2349,8 +2349,8 @@ mbgl::Duration MGLDurationInSeconds(NSTimeInterval duration)
     mbgl::AnimationOptions animationOptions;
     if (duration > 0)
     {
-        animationOptions.duration = MGLDurationInSeconds(duration);
-        animationOptions.easing = MGLUnitBezierForMediaTimingFunction(function);
+        animationOptions.duration.emplace(MGLDurationInSeconds(duration));
+        animationOptions.easing.emplace(MGLUnitBezierForMediaTimingFunction(function));
     }
     if (completion)
     {
@@ -2456,8 +2456,8 @@ mbgl::Duration MGLDurationInSeconds(NSTimeInterval duration)
     mbgl::AnimationOptions animationOptions;
     if (duration > 0)
     {
-        animationOptions.duration = MGLDurationInSeconds(duration);
-        animationOptions.easing = MGLUnitBezierForMediaTimingFunction(function);
+        animationOptions.duration.emplace(MGLDurationInSeconds(duration));
+        animationOptions.easing.emplace(MGLUnitBezierForMediaTimingFunction(function));
     }
     if (completion)
     {

platform/macos/src/MGLMapView.mm

@@ -1037,8 +1037,8 @@ public:
     mbgl::CameraOptions cameraOptions = [self cameraOptionsObjectForAnimatingToCamera:camera];
     mbgl::AnimationOptions animationOptions;
     if (duration > 0) {
-        animationOptions.duration = MGLDurationInSeconds(duration);
-        animationOptions.easing = MGLUnitBezierForMediaTimingFunction(function);
+        animationOptions.duration.emplace(MGLDurationInSeconds(duration));
+        animationOptions.easing.emplace(MGLUnitBezierForMediaTimingFunction(function));
     }
     if (completion) {
         animationOptions.transitionFinishFn = [completion]() {