created retentive class family

lib/CMakeLists.txt

@@ -1,7 +1,7 @@
 
 add_library(nm_utils STATIC
 	"Window.cpp"
- "RetentiveArray.hpp")
+ "RetentiveArray.hpp" "RetentiveObject.hpp" "RetentiveEntity.hpp")
 
 target_include_directories(nm_utils PUBLIC ${SDL2_INCLUDE_DIRS} ${CMAKE_CURRENT_SOURCE_DIR})
 target_link_libraries(nm_utils PUBLIC ${SDL2_LIBRARIES})

lib/RetentiveArray.hpp

@@ -1,8 +1,6 @@
 #pragma once
 
-#include <vector>
-#include <array>
-#include <functional>
+#include "RetentiveEntity.hpp"
 
 /**
 * @brief An array that remembers its past.
@@ -24,7 +22,7 @@ template<
 	typename Type, 
 	unsigned int AttentionSpan, 
 	typename std::enable_if_t<(AttentionSpan > 0), bool> = true>
-class RetentiveArray
+class RetentiveArray : public RetentiveEntity<std::vector<Type>, AttentionSpan>
 {
 public:
 	/**
@@ -104,77 +102,14 @@ public:
 		// Do nothing
 	}
 
-	/**
-	 * @brief Get the array from `index` generations ago
-	 * 
-	 * @param index Amount of generations to go backwards in time
-	 * @return The array from before `index` generations
-	 */
-	std::vector<Type>& operator[](size_t index)
-	{
-		return data[index];
-	}
-
-	/**
-	 * @brief Get the most up-to-date array
-	 * 
-	 * @return The array with generation 0
-	 */
-	std::vector<Type>& Current()
-	{
-		return data[0];
-	}
-
-	/**
-	 * @brief Evolve the data in the array
-	 * 
-	 * Simply calls the member function pointer. The called function is then
-	 * supposed to perform whatever is needed to compute the new array contents.
-	 * 
-	 * The data is swapped BEFORE calling this function, so the evolution function should
-	 * modify the data in the Current() vector (index 0)
-	 */
-	void Evolve()
-	{
-		// Evolve the array
-		Evolve(rule);
-	}
-
-	/**
-	 * @brief Evolve the data in the array
-	 *
-	 * Simply calls the provided function pointer. The called function is then
-	 * supposed to perform whatever is needed to compute the new array contents.
-	 *
-	 * The data is swapped BEFORE calling this function, so the evolution function should
-	 * modify the data in the Current() vector (index 0)
-	 * 
-	 * @param rule A function that evolves the data in the array
-	 */
-	void Evolve(std::function<void(void)> rule)
+private:
+	void CycleGenerations() override
 	{
 		// Cycle the array contents, so that the previous "current" array is now the 2nd. 
 		// The 2nd becomes the 3rd etc, and the former last array becomes the new current
 		for (int n = 1; n <= AttentionSpan; n++)
 		{
-			data[0].swap(data[1]);
+			data[0].swap(data[n]);
 		}
-
-		rule();
 	}
-
-	/**
-	 * @brief Set a general rule for evolving the data
-	 * 
-	 * @param rule The new evolution rule
-	 */
-	void SetEvolutionRule(std::function<void(void)> rule)
-	{
-		this->rule = rule;
-	}
-
-
-private:
-	std::array<std::vector<Type>, AttentionSpan + 1> data;
-	std::function<void(void)> rule = std::bind([]() {});	// Do nothing by default
 };

lib/RetentiveEntity.hpp

@@ -0,0 +1,99 @@
+#pragma once
+
+#include <vector>
+#include <array>
+#include <functional>
+
+/**
+ * @brief Abstract base type for all retentive things
+ *
+ * @tparam Type The object to give a memory to
+ * @tparam AttentionSpan How many generations of the data will be remembered by the object
+ */
+template<
+	typename Type,
+	unsigned int AttentionSpan,
+	typename std::enable_if_t<(AttentionSpan > 0), bool> = true>
+class RetentiveEntity
+{
+public:
+	RetentiveEntity() {}
+	RetentiveEntity(const RetentiveEntity<Type, AttentionSpan>& other) = delete;
+	RetentiveEntity(RetentiveEntity<Type, AttentionSpan>&& other) = delete;
+	RetentiveEntity<Type, AttentionSpan>& operator=(const RetentiveEntity<Type, AttentionSpan>& other) = delete;
+	RetentiveEntity<Type, AttentionSpan>& operator=(RetentiveEntity<Type, AttentionSpan>&& other) = delete;
+
+	/**
+	 * @brief Get the entity from `index` generations ago
+	 *
+	 * @param index Amount of generations to go backwards in time
+	 * @return The entity from before `index` generations
+	 */
+	virtual Type& operator[](size_t index)
+	{
+		return data[index];
+	}
+
+	/**
+	 * @brief Get the most up-to-date entity
+	 *
+	 * @return The entity with generation 0
+	 */
+	virtual Type& Current()
+	{
+		return data[0];
+	}
+
+	/**
+	 * @brief Evolve the data in the entity
+	 *
+	 * Simply calls the member function pointer. The called function is then
+	 * supposed to perform whatever is needed to compute the new object contents.
+	 *
+	 * The data is swapped BEFORE calling this function, so the evolution function should
+	 * modify the data in the Current() vector (index 0)
+	 */
+	void Evolve()
+	{
+		// Evolve the object
+		CycleGenerations();
+		rule();
+	}
+
+	/**
+	 * @brief Evolve the data in the object
+	 *
+	 * Simply calls the provided function pointer. The called function is then
+	 * supposed to perform whatever is needed to compute the new object contents.
+	 *
+	 * The data is swapped BEFORE calling this function, so the evolution function should
+	 * modify the data in the Current() vector (index 0)
+	 *
+	 * @param rule A function that evolves the data in the object
+	 */
+	void Evolve(std::function<void(void)> rule)
+	{
+		CycleGenerations();
+		rule();
+	}
+
+	/**
+	 * @brief Set a general rule for evolving the data
+	 *
+	 * @param rule The new evolution rule
+	 */
+	void SetEvolutionRule(std::function<void(void)> rule)
+	{
+		this->rule = rule;
+	}
+
+protected:
+	/**
+	 * @brief Swaps the objects in the array
+	 */
+	virtual void CycleGenerations() = 0;
+
+protected:
+	std::array<Type, AttentionSpan + 1> data;
+	std::function<void(void)> rule = std::bind([]() {});	// Do nothing by default
+};

lib/RetentiveObject.hpp

@@ -0,0 +1,149 @@
+#pragma once
+
+#include "RetentiveEntity.hpp"
+
+/**
+ * @brief An object that remembers its past.
+ *
+ * You most likely want to use a RetentiveArray instead.
+ * This structure is only really useful if you have a custom container class
+ * that you need to evolve over time.
+ * 
+ * A retentive object is a kind of buffered object that "remembers"
+ * the state of the object from the last n generations.
+ *
+ * This structure handles the evolution of these kinds of objects and takes
+ * care of the memory allocation/freeing as well as properly swapping the
+ * object pointers.
+ *
+ * @tparam Type The object to give a memory to
+ * @tparam AttentionSpan How many generations of the data will be remembered by the object
+ */
+template<
+	typename Type,
+	unsigned int AttentionSpan,
+	typename std::enable_if_t<(AttentionSpan > 0), bool> = true>
+class RetentiveObject : public RetentiveEntity<Type*, AttentionSpan>
+{
+public:
+	/**
+	 * @brief Constructs a new, empty retentive object
+	 */
+	RetentiveObject()
+	{
+		// Create new vectors for every generation that needs to be remembered
+		for (int n = 0; n <= AttentionSpan; n++)
+		{
+			data[n] = new Type();
+		}
+	}
+
+	/**
+	 * @brief Constructs a new, empty retentive object
+	 *
+	 * @param size The size of the data contained in the object
+	 */
+	RetentiveObject(const Type& initVal)
+	{
+		// Create new vectors for every generation that needs to be remembered
+		for (int n = 0; n <= AttentionSpan; n++)
+		{
+			data[n] = new Type(initVal);
+		}
+	}
+
+	/**
+	 * @brief Constructs a new retentive object with the data of another object
+	 *
+	 * @param other The retentive object to copy from
+	 */
+	RetentiveObject<Type, AttentionSpan>& operator=(const RetentiveObject<Type, AttentionSpan>& other)
+	{
+		for (int n = 0; n <= AttentionSpan; n++)
+		{
+			*data[n] = *other.data[n];
+		}
+
+		return *this;
+	}
+
+	/**
+	 * @brief Constructs a new retentive object pointing to the data of an rvalue
+	 *
+	 * @param other The retentive object to set its data to
+	 */
+	RetentiveObject<Type, AttentionSpan>& operator=(RetentiveObject<Type, AttentionSpan>&& other)
+	{
+		for (int n = 0; n <= AttentionSpan; n++)
+		{
+			data[n] = other.data[n];
+			other.data[n] = nullptr;
+		}
+
+		return *this;
+	}
+
+	/**
+	 * @brief Constructs a new retentive object with the data of another object
+	 *
+	 * @param other The retentive object to copy from
+	 */
+	RetentiveObject(const RetentiveObject<Type, AttentionSpan>& other)
+	{
+		*this = other;
+	}
+
+	/**
+	 * @brief Constructs a new retentive object pointing to the data of an rvalue
+	 *
+	 * @param other The retentive object to set its data to
+	 */
+	RetentiveObject(RetentiveObject<Type, AttentionSpan>&& other)
+	{
+		*this = other;
+	}
+
+	~RetentiveObject()
+	{
+		for (int n = 0; n <= AttentionSpan; n++)
+		{
+			if (data[n] != nullptr)
+				delete data[n];
+		}
+	}
+
+	/**
+	 * @brief Get the object from `index` generations ago
+	 *
+	 * @param index Amount of generations to go backwards in time
+	 * @return The object from before `index` generations
+	 */
+	Type& operator[](size_t index) override
+	{
+		return *(data[index]);
+	}
+
+	/**
+	 * @brief Get the most up-to-date object
+	 *
+	 * @return The object with generation 0
+	 */
+	Type& Current() override
+	{
+		return *(data[0]);
+	}
+
+private:
+	/**
+	 * @brief Swaps the objects in the array
+	 */
+	void CycleGenerations() override
+	{
+		// Cycle the object contents, so that the previous "current" object is now the 2nd. 
+		// The 2nd becomes the 3rd etc, and the former last object becomes the new current
+		for (int n = 1; n <= AttentionSpan; n++)
+		{
+			std::swap(data[0], data[n]);
+		}
+	}
+};