Camera movement

engine-api/modules/Input.cppm

@@ -9,7 +9,7 @@ export namespace ee_engine
     struct InputHandlers
     {
         std::function<void(float dx, float dy)> zooming;
-        std::function<void(float dx, float dy)> mapScroll;
+        std::function<void(float x, float y, float lastX, float lastY)> mapScroll;
     };
 
     class IInput
@@ -21,6 +21,9 @@ export namespace ee_engine
     protected:
         InputHandlers handlers;
 
+        float mouseX = 0.0f, mouseY = 0.0f;
+        float lastMouseX = 0.0f, lastMouseY = 0.0f;
+
         explicit IInput(const InputHandlers &handlers) {this->handlers = handlers;};
     };
 }

engine-api/modules/Render.cppm

@@ -69,7 +69,8 @@ export namespace ee_engine
         void SetCamera(const CameraTransform &camera);
 
         constexpr CameraTransform getCamera() const noexcept {return camera;};
-
+        glm::vec2 ScreenToWorld(const float screenx, const float screenY);
+        glm::vec2 ScreenToWorld(const glm::vec2 &screenPos);
 
 
     protected:
@@ -78,6 +79,7 @@ export namespace ee_engine
         float screenAspect;
         CameraTransform camera;
         glm::mat4 viewProjection;
+        glm::mat4 viewProjectionInversed;
 
         GLFWwindow *window;
         MapMesh *mapMesh;

engine-api/src/Render.cpp

@@ -72,10 +72,28 @@ void ee_engine::IRenderer::SetCamera(const CameraTransform &camera)
     );
 
     viewProjection = P * V;
+    viewProjectionInversed = glm::inverse(viewProjection);
 
     ApplyCamera();
 }
 
+glm::vec2 ee_engine::IRenderer::ScreenToWorld(const float screenX, const float screenY)
+{
+    return ScreenToWorld(glm::vec2(screenX, screenY));
+}
+
+glm::vec2 ee_engine::IRenderer::ScreenToWorld(const glm::vec2 &screenPos)
+{
+    float x = 2.0f * screenPos.x / screenWidth - 1.0f;
+    float y = -2.0f * screenPos.y / screenHeight + 1.0f;
+
+    glm::vec4 ndc(x, y, 0.0f, 1.0f);
+
+    glm::vec4 world = viewProjectionInversed * ndc;
+
+    return glm::vec2(world) / world.w;
+}
+
 void ee_engine::IRenderer::UpdateRegionCmd(ee_engine::RendererCommand &command)
 {
     if (!regionsMapping.contains(command.region.id))

engine/modules/Actions.cppm

@@ -10,7 +10,7 @@ export
 
     private:
         static void Zoom(float dx, float dy);
-        static void MapScroll(float dx, float dy);
+        static void MapScroll(float x, float y, float lastX, float lastY);
 
         Actions();
     };

engine/modules/GLFWInput.cppm

@@ -12,5 +12,10 @@ export {
         GLFWInput(ee_engine::InputHandlers handlers);
 
         void Poll() override;
+
+    private:
+        void OnLeftMouseButton(int state);
+        void OnRightMouseButton(int state);
+        void OnMiddleMouseButton(int state);
     };
 }

engine/src/Actions.cpp

@@ -1,6 +1,7 @@
 module;
 
 #include <cmath>
+#include <glm/glm.hpp>
 
 module Actions;
 import Engine;
@@ -17,7 +18,13 @@ void Actions::Zoom(float dx, float dy)
     Engine::renderer->SetCamera(cam);
 }
 
-void Actions::MapScroll(float dx, float dy)
+void Actions::MapScroll(float x, float y, float lastX, float lastY)
 {
+    ee_engine::CameraTransform cam = Engine::renderer->getCamera();
 
+    glm::vec2 pos = Engine::renderer->ScreenToWorld(x, y);
+    glm::vec2 lastPos = Engine::renderer->ScreenToWorld(lastX, lastY);
+    cam.position -= pos - lastPos;
+
+    Engine::renderer->SetCamera(cam);
 }

engine/src/GLFWInput.cpp

@@ -3,16 +3,17 @@ module;
 #include "Logger.h"
 #include <GLFW/glfw3.h>
 
+#define GLFW_GET_INPUT reinterpret_cast<GLFWInput*>(glfwGetWindowUserPointer(window))
+#define GLFW_CALLBACK(callback, ...) GLFW_GET_INPUT->handlers.callback(__VA_ARGS__);
+
 module GLFWInput;
 import Engine;
 
 GLFWInput::GLFWInput(ee_engine::InputHandlers handlers) : ee_engine::IInput(handlers)
 {
     glfwSetWindowUserPointer(Engine::window, this);
-
     glfwSetScrollCallback(Engine::window, [](GLFWwindow *window, double dx, double dy) {
-        reinterpret_cast<GLFWInput*>(glfwGetWindowUserPointer(window))->
-                handlers.zooming(static_cast<float>(dx), static_cast<float>(dy));
+        GLFW_CALLBACK(zooming, static_cast<float>(dx), static_cast<float>(dy));
     });
 
     LOG(INFO, "Input mappings initialized");
@@ -20,5 +21,39 @@ GLFWInput::GLFWInput(ee_engine::InputHandlers handlers) : ee_engine::IInput(hand
 
 void GLFWInput::Poll()
 {
+    double mouseX, mouseY;
+    glfwGetCursorPos(Engine::window, &mouseX, &mouseY);
+    this->mouseX = static_cast<float>(mouseX);
+    this->mouseY = static_cast<float>(mouseY);
 
+    int LMB = glfwGetMouseButton(Engine::window, GLFW_MOUSE_BUTTON_LEFT);
+    int RMB = glfwGetMouseButton(Engine::window, GLFW_MOUSE_BUTTON_RIGHT);
+    int MMB = glfwGetMouseButton(Engine::window, GLFW_MOUSE_BUTTON_MIDDLE);
+
+    OnLeftMouseButton(LMB);
+    OnRightMouseButton(RMB);
+    OnMiddleMouseButton(MMB);
+
+    lastMouseX = this->mouseX;
+    lastMouseY = this->mouseY;
+}
+
+void GLFWInput::OnLeftMouseButton(int state){}
+void GLFWInput::OnRightMouseButton(int state){}
+
+void GLFWInput::OnMiddleMouseButton(int state)
+{
+    switch(state)
+    {
+        case GLFW_PRESS:
+        {
+            handlers.mapScroll(mouseX, mouseY, lastMouseX, lastMouseY);
+            break;
+        }
+
+        case GLFW_RELEASE:
+        {
+            break;
+        }
+    }
 }