[core] Implement CrossFadedDataDrivenProperty to add support for feature expressions in `*-pattern` properties

2 files changed, 26 insertions, 13 deletions

diff --git a/src/mbgl/gl/uniform.cpp b/src/mbgl/gl/uniform.cpp
index 2946980c19..3d8a8d53d9 100644
--- a/src/mbgl/gl/uniform.cpp
+++ b/src/mbgl/gl/uniform.cpp
@@ -79,6 +79,11 @@ void bindUniform<std::array<uint16_t, 2>>(UniformLocation location, const std::a
     bindUniform(location, util::convert<float>(t));
 }
 
+template <>
+void bindUniform<std::array<uint16_t, 4>>(UniformLocation location, const std::array<uint16_t, 4>& t) {
+    bindUniform(location, util::convert<float>(t));
+}
+
 // Add more as needed.
 
 #ifndef NDEBUG
@@ -125,6 +130,12 @@ bool verifyUniform<std::array<float, 3>>(const ActiveUniform& uniform) {
 }
 
 template <>
+bool verifyUniform<std::array<float, 4>>(const ActiveUniform& uniform) {
+    assert(uniform.size == 1 && uniform.type == UniformDataType::FloatVec4);
+    return true;
+}
+
+template <>
 bool verifyUniform<std::array<double, 16>>(const ActiveUniform& uniform) {
     assert(uniform.size == 1 && uniform.type == UniformDataType::FloatMat4);
     return true;
@@ -168,6 +179,14 @@ bool verifyUniform<std::array<uint16_t, 2>>(const ActiveUniform& uniform) {
     return true;
 }
 
+template <>
+bool verifyUniform<std::array<uint16_t, 4>>(const ActiveUniform& uniform) {
+    assert(uniform.size == 1 &&
+           (uniform.type == UniformDataType::IntVec4 ||
+            uniform.type == UniformDataType::FloatVec4));
+    return true;
+}
+
 // Add more as needed.
 
 #endif
diff --git a/src/mbgl/gl/uniform.hpp b/src/mbgl/gl/uniform.hpp
index d8a167c382..f8eaf369a2 100644
--- a/src/mbgl/gl/uniform.hpp
+++ b/src/mbgl/gl/uniform.hpp
@@ -16,13 +16,6 @@ namespace gl {
 template <class T>
 void bindUniform(UniformLocation, const T&);
 
-template <class Tag, class T>
-class UniformValue {
-public:
-    explicit UniformValue(T t_) : t(std::move(t_)) {}
-    T t;
-};
-
 class ActiveUniform {
 public:
     std::size_t size;
@@ -42,7 +35,8 @@ ActiveUniforms activeUniforms(ProgramID);
 template <class Tag, class T>
 class Uniform {
 public:
-    using Value = UniformValue<Tag, T>;
+    // TODO should maybe remove this altogether bc it is now redundant?
+    using Value = T;
 
     using Type = T;
 
@@ -50,10 +44,10 @@ public:
     public:
         State(UniformLocation location_) : location(std::move(location_)) {}
 
-        void operator=(const Value& value) {
-            if (location >= 0 && (!current || *current != value.t)) {
-                current = value.t;
-                bindUniform(location, value.t);
+        void operator=(const Type& value) {
+            if (location >= 0 && (!current || *current != value)) {
+                current = value;
+                bindUniform(location, value);
             }
         }
 
@@ -103,7 +97,7 @@ public:
                    : false)... });
 #endif
 
-        return State { { uniformLocation(id, Us::name()) }... };
+        return State(uniformLocation(id, Us::name())...);
     }
 
     template <class Program>