Added Input class and Layer::OnUpdate with timestep

- Input class supports querying keyboard and mouse states

Walnut/premake5.lua

@@ -9,6 +9,8 @@ project "Walnut"
 
    includedirs
    {
+      "src",
+
       "../vendor/imgui",
       "../vendor/glfw/include",
       "../vendor/stb_image",

Walnut/src/Walnut/Application.cpp

@@ -12,6 +12,7 @@
 #define GLFW_INCLUDE_VULKAN
 #include <GLFW/glfw3.h>
 #include <vulkan/vulkan.h>
+#include <glm/glm.hpp>
 
 #include <iostream>
 
@@ -54,6 +55,8 @@ static std::vector<std::vector<std::function<void()>>> s_ResourceFreeQueue;
 // and is always guaranteed to increase (eg. 0, 1, 2, 0, 1, 2)
 static uint32_t s_CurrentFrameIndex = 0;
 
+static Walnut::Application* s_Instance = nullptr;
+
 void check_vk_result(VkResult err)
 {
 	if (err == 0)
@@ -384,12 +387,21 @@ namespace Walnut {
 	Application::Application(const ApplicationSpecification& specification)
 		: m_Specification(specification)
 	{
+		s_Instance = this;
+
 		Init();
 	}
 
 	Application::~Application()
 	{
 		Shutdown();
+
+		s_Instance = nullptr;
+	}
+
+	Application& Application::Get()
+	{
+		return *s_Instance;
 	}
 
 	void Application::Init()
@@ -557,6 +569,9 @@ namespace Walnut {
 			// Generally you may always pass all inputs to dear imgui, and hide them from your application based on those two flags.
 			glfwPollEvents();
 
+			for (auto& layer : m_LayerStack)
+				layer->OnUpdate(m_TimeStep);
+
 			// Resize swap chain?
 			if (g_SwapChainRebuild)
 			{
@@ -659,6 +674,11 @@ namespace Walnut {
 			// Present Main Platform Window
 			if (!main_is_minimized)
 				FramePresent(wd);
+
+			float time = GetTime();
+			m_FrameTime = time - m_LastFrameTime;
+			m_TimeStep = glm::min<float>(m_FrameTime, 0.0333f);
+			m_LastFrameTime = time;
 		}
 
 	}
@@ -668,6 +688,11 @@ namespace Walnut {
 		m_Running = false;
 	}
 
+	float Application::GetTime()
+	{
+		return (float)glfwGetTime();
+	}
+
 	VkInstance Application::GetInstance()
 	{
 		return g_Instance;

Walnut/src/Walnut/Application.h

@@ -29,6 +29,8 @@ namespace Walnut {
 		Application(const ApplicationSpecification& applicationSpecification = ApplicationSpecification());
 		~Application();
 
+		static Application& Get();
+
 		void Run();
 		void SetMenubarCallback(const std::function<void()>& menubarCallback) { m_MenubarCallback = menubarCallback; }
 
@@ -43,6 +45,9 @@ namespace Walnut {
 
 		void Close();
 
+		float GetTime();
+		GLFWwindow* GetWindowHandle() const { return m_WindowHandle; }
+
 		static VkInstance GetInstance();
 		static VkPhysicalDevice GetPhysicalDevice();
 		static VkDevice GetDevice();
@@ -59,6 +64,10 @@ namespace Walnut {
 		GLFWwindow* m_WindowHandle = nullptr;
 		bool m_Running = false;
 
+		float m_TimeStep = 0.0f;
+		float m_FrameTime = 0.0f;
+		float m_LastFrameTime = 0.0f;
+
 		std::vector<std::shared_ptr<Layer>> m_LayerStack;
 		std::function<void()> m_MenubarCallback;
 	};

Walnut/src/Walnut/Input/Input.cpp

@@ -0,0 +1,38 @@
+#include "Input.h"
+
+#include "Walnut/Application.h"
+
+#include <GLFW/glfw3.h>
+
+namespace Walnut {
+
+	bool Input::IsKeyDown(KeyCode keycode)
+	{
+		GLFWwindow* windowHandle = Application::Get().GetWindowHandle();
+		int state = glfwGetKey(windowHandle, (int)keycode);
+		return state == GLFW_PRESS || state == GLFW_REPEAT;
+	}
+
+	bool Input::IsMouseButtonDown(MouseButton button)
+	{
+		GLFWwindow* windowHandle = Application::Get().GetWindowHandle();
+		int state = glfwGetMouseButton(windowHandle, (int)button);
+		return state == GLFW_PRESS;
+	}
+
+	glm::vec2 Input::GetMousePosition()
+	{
+		GLFWwindow* windowHandle = Application::Get().GetWindowHandle();
+
+		double x, y;
+		glfwGetCursorPos(windowHandle, &x, &y);
+		return { (float)x, (float)y };
+	}
+
+	void Input::SetCursorMode(CursorMode mode)
+	{
+		GLFWwindow* windowHandle = Application::Get().GetWindowHandle();
+		glfwSetInputMode(windowHandle, GLFW_CURSOR, GLFW_CURSOR_NORMAL + (int)mode);
+	}
+
+}

Walnut/src/Walnut/Input/Input.h

@@ -0,0 +1,20 @@
+#pragma once
+
+#include "KeyCodes.h"
+
+#include <glm/glm.hpp>
+
+namespace Walnut {
+
+	class Input
+	{
+	public:
+		static bool IsKeyDown(KeyCode keycode);
+		static bool IsMouseButtonDown(MouseButton button);
+
+		static glm::vec2 GetMousePosition();
+
+		static void SetCursorMode(CursorMode mode);
+	};
+
+}

Walnut/src/Walnut/Input/KeyCodes.h

@@ -0,0 +1,184 @@
+#pragma once
+
+#include <stdint.h>
+#include <iostream>
+
+namespace Walnut {
+
+	typedef enum class KeyCode : uint16_t
+	{
+		// From glfw3.h
+		Space = 32,
+		Apostrophe = 39, /* ' */
+		Comma = 44, /* , */
+		Minus = 45, /* - */
+		Period = 46, /* . */
+		Slash = 47, /* / */
+
+		D0 = 48, /* 0 */
+		D1 = 49, /* 1 */
+		D2 = 50, /* 2 */
+		D3 = 51, /* 3 */
+		D4 = 52, /* 4 */
+		D5 = 53, /* 5 */
+		D6 = 54, /* 6 */
+		D7 = 55, /* 7 */
+		D8 = 56, /* 8 */
+		D9 = 57, /* 9 */
+
+		Semicolon = 59, /* ; */
+		Equal = 61, /* = */
+
+		A = 65,
+		B = 66,
+		C = 67,
+		D = 68,
+		E = 69,
+		F = 70,
+		G = 71,
+		H = 72,
+		I = 73,
+		J = 74,
+		K = 75,
+		L = 76,
+		M = 77,
+		N = 78,
+		O = 79,
+		P = 80,
+		Q = 81,
+		R = 82,
+		S = 83,
+		T = 84,
+		U = 85,
+		V = 86,
+		W = 87,
+		X = 88,
+		Y = 89,
+		Z = 90,
+
+		LeftBracket = 91,  /* [ */
+		Backslash = 92,  /* \ */
+		RightBracket = 93,  /* ] */
+		GraveAccent = 96,  /* ` */
+
+		World1 = 161, /* non-US #1 */
+		World2 = 162, /* non-US #2 */
+
+		/* Function keys */
+		Escape = 256,
+		Enter = 257,
+		Tab = 258,
+		Backspace = 259,
+		Insert = 260,
+		Delete = 261,
+		Right = 262,
+		Left = 263,
+		Down = 264,
+		Up = 265,
+		PageUp = 266,
+		PageDown = 267,
+		Home = 268,
+		End = 269,
+		CapsLock = 280,
+		ScrollLock = 281,
+		NumLock = 282,
+		PrintScreen = 283,
+		Pause = 284,
+		F1 = 290,
+		F2 = 291,
+		F3 = 292,
+		F4 = 293,
+		F5 = 294,
+		F6 = 295,
+		F7 = 296,
+		F8 = 297,
+		F9 = 298,
+		F10 = 299,
+		F11 = 300,
+		F12 = 301,
+		F13 = 302,
+		F14 = 303,
+		F15 = 304,
+		F16 = 305,
+		F17 = 306,
+		F18 = 307,
+		F19 = 308,
+		F20 = 309,
+		F21 = 310,
+		F22 = 311,
+		F23 = 312,
+		F24 = 313,
+		F25 = 314,
+
+		/* Keypad */
+		KP0 = 320,
+		KP1 = 321,
+		KP2 = 322,
+		KP3 = 323,
+		KP4 = 324,
+		KP5 = 325,
+		KP6 = 326,
+		KP7 = 327,
+		KP8 = 328,
+		KP9 = 329,
+		KPDecimal = 330,
+		KPDivide = 331,
+		KPMultiply = 332,
+		KPSubtract = 333,
+		KPAdd = 334,
+		KPEnter = 335,
+		KPEqual = 336,
+
+		LeftShift = 340,
+		LeftControl = 341,
+		LeftAlt = 342,
+		LeftSuper = 343,
+		RightShift = 344,
+		RightControl = 345,
+		RightAlt = 346,
+		RightSuper = 347,
+		Menu = 348
+	} Key;
+
+	enum class KeyState
+	{
+		None = -1,
+		Pressed,
+		Held,
+		Released
+	};
+
+	enum class CursorMode
+	{
+		Normal = 0,
+		Hidden = 1,
+		Locked = 2
+	};
+
+	typedef enum class MouseButton : uint16_t
+	{
+		Button0 = 0,
+		Button1 = 1,
+		Button2 = 2,
+		Button3 = 3,
+		Button4 = 4,
+		Button5 = 5,
+		Left = Button0,
+		Right = Button1,
+		Middle = Button2
+	} Button;
+
+
+	inline std::ostream& operator<<(std::ostream& os, KeyCode keyCode)
+	{
+		os << static_cast<int32_t>(keyCode);
+		return os;
+	}
+
+	inline std::ostream& operator<<(std::ostream& os, MouseButton button)
+	{
+		os << static_cast<int32_t>(button);
+		return os;
+	}
+}
+

Walnut/src/Walnut/Layer.h

@@ -10,6 +10,7 @@ namespace Walnut {
 		virtual void OnAttach() {}
 		virtual void OnDetach() {}
 
+		virtual void OnUpdate(float ts) {}
 		virtual void OnUIRender() {}
 	};