Moves the joystick class towards accepting analogue inputs.

Inputs/Joystick.hpp

@@ -21,29 +21,57 @@ class Joystick {
 	public:
 		virtual ~Joystick() {}
 
-		struct DigitalInput {
+		struct Input {
+			/// Defines the broad type of the input.
 			enum Type {
-				Up, Down, Left, Right, Fire,
+				// Half-axis inputs.
+				Up, Down, Left, Right,
+				// Full-axis inputs.
+				Horizontal, Vertical,
+				// Fire buttons.
+				Fire,
+				// Other labelled keys.
 				Key
-			} type;
-			union {
+			};
+			const Type type;
+
+			enum Precision {
+				Analogue, Digital
+			};
+			const Precision precision;
+
+			/*!
+				Holds extra information pertaining to the input.
+
+				@c Type::Key inputs declare the symbol printed on them.
+
+				All other types of input have an associated index, indicating whether they
+				are the zeroth, first, second, third, etc of those things. E.g. a joystick
+				may have two fire buttons, which will be buttons 0 and 1.
+			*/
+			union Info {
 				struct {
 					int index;
 				} control;
 				struct {
 					wchar_t symbol;
 				} key;
-			} info;
+			};
+			Info info;
+			// TODO: Find a way to make the above safely const; may mean not using a union.
 
-			DigitalInput(Type type, int index = 0) : type(type) {
+			Input(Type type, int index = 0, Precision precision = Precision::Digital) :
+				type(type),
+				precision(precision) {
 				info.control.index = index;
 			}
-			DigitalInput(wchar_t symbol) : type(Key) {
+			Input(wchar_t symbol) : type(Key), precision(Precision::Digital) {
 				info.key.symbol = symbol;
 			}
 
-			bool operator == (const DigitalInput &rhs) {
+			bool operator == (const Input &rhs) {
 				if(rhs.type != type) return false;
+				if(rhs.precision != precision) return false;
 				if(rhs.type == Key) {
 					return rhs.info.key.symbol == info.key.symbol;
 				} else {
@@ -52,13 +80,16 @@ class Joystick {
 			}
 		};
 
-		virtual std::vector<DigitalInput> get_inputs() = 0;
+		virtual std::vector<Input> get_inputs() = 0;
+
+		// Host interface. Note that the two set_inputs have logic to map
+		// between analogue and digital inputs; if you override 
+		virtual void set_input(const Input &input, bool is_active) = 0;
+		virtual void set_input(const Input &input, float value) {}
 
-		// Host interface.
-		virtual void set_digital_input(const DigitalInput &digital_input, bool is_active) = 0;
 		virtual void reset_all_inputs() {
 			for(const auto &input: get_inputs()) {
-				set_digital_input(input, false);
+				set_input(input, false);
 			}
 		}
 };