ADD: MousePicker

CMakeLists.txt

@@ -55,7 +55,10 @@ add_executable(Dicewars_Siedler src/main.cpp
         src/engine/renderer/loader/OBJLoader.cpp
         src/engine/renderer/loader/OBJLoader.h
         src/engine/layer/entities/Light.cpp
-        src/engine/layer/entities/Light.h)
+        src/engine/layer/entities/Light.h
+        src/engine/platform/glfw/MousePicker.cpp
+        src/engine/platform/glfw/MousePicker.h
+)
 
 target_include_directories(Dicewars_Siedler PRIVATE
     lib/glfw/include

src/engine/layer/GameLayer.cpp

@@ -9,6 +9,7 @@
 #include "../renderer/loader/OBJLoader.h"
 #include "../renderer/model/TexturedModel.h"
 #include "../renderer/textures/ModelTexture.h"
+#include "../toolbox/MathUtils.h"
 #include "entities/Light.h"
 
 GameLayer::GameLayer() :texturedModel(0,0) //Platzhalter, echtes Model kommt in onAttach
@@ -40,6 +41,7 @@ void GameLayer::onAttach()
     entity = std::make_unique<Entity>(Entity(std::make_shared<TexturedModel>(texturedModel), glm::vec3(0,0,-25), 0,0,0, 1.f));
     camera = std::make_unique<Camera>();
     light = std::make_unique<Light>(glm::vec3(0,0,-20), glm::vec3(1,1,1));
+    mousePicker = std::make_unique<MousePicker>(renderer.getProjectionMatrix(), MathUtils::createViewMatrix(*camera));
 }
 
 void GameLayer::onDetach()
@@ -49,6 +51,8 @@ void GameLayer::onDetach()
 
 void GameLayer::onUpdate()
 {
+    mousePicker->update(*camera);
+    printf("Mouse Ray: %f, %f, %f\n", mousePicker->getCurrentRay().x, mousePicker->getCurrentRay().y, mousePicker->getCurrentRay().z);
     glm::vec3 moveDir = glm::vec3(0,0,0);
     if (InputManager::isKeyPressed(GLFW_KEY_W)) moveDir.z -= 1.0f;
     if (InputManager::isKeyPressed(GLFW_KEY_S)) moveDir.z += 1.0f;

src/engine/layer/GameLayer.h

@@ -5,6 +5,7 @@
 #ifndef DICEWARS_SIEDLER_GAMELAYER_H
 #define DICEWARS_SIEDLER_GAMELAYER_H
 #include "Layer.h"
+#include "../platform/glfw/MousePicker.h"
 #include "../renderer/Renderer.h"
 #include "../renderer/loader/Loader.h"
 #include "../renderer/model/TexturedModel.h"
@@ -26,6 +27,7 @@ private:
     std::unique_ptr<Entity> entity;
     std::unique_ptr<Camera> camera;
     std::unique_ptr<Light> light;
+    std::unique_ptr<MousePicker> mousePicker;
     Renderer renderer;
 };
 

src/engine/platform/glfw/InputManager.cpp

@@ -17,6 +17,13 @@ bool InputManager::isMouseButtonPressed(int button) {
     return glfwGetMouseButton(window, button) == GLFW_PRESS;
 }
 
+glm::vec2 InputManager::getMousePosition() {
+    auto window = static_cast<GLFWwindow*>(Application::getInstance().getWindow().GetNativeWindow());
+    double xpos, ypos;
+    glfwGetCursorPos(window, &xpos, &ypos);
+    return {xpos, ypos};
+}
+
 glm::vec2 InputManager::getMouseDelta() {
     static double lastX = 0, lastY = 0;
     double xpos, ypos;

src/engine/platform/glfw/InputManager.h

@@ -11,6 +11,8 @@ class InputManager {
 public:
     static bool isKeyPressed(int keycode);
     static bool isMouseButtonPressed(int button);
+
+    static glm::vec2 getMousePosition();
     glm::vec2 getMouseDelta();
 
 };

src/engine/platform/glfw/MousePicker.cpp

@@ -0,0 +1,43 @@
+//
+// Created by sebastian on 07.02.26.
+//
+
+#include "MousePicker.h"
+
+#include "InputManager.h"
+#include "../../core/Application.h"
+#include "../../toolbox/MathUtils.h"
+
+
+void MousePicker::update(const Camera& camera) {
+    viewMatrix = MathUtils::createViewMatrix(camera);
+    currentRay = calculateMouseRay();
+}
+
+glm::vec3 MousePicker::calculateMouseRay() {
+    glm::vec2 mouseXY = InputManager::getMousePosition();
+
+    glm::vec2 normalizedDeviceCoords = getNormalizedDeviceCoords(mouseXY.x, mouseXY.y);
+    glm::vec4 clipCoords = glm::vec4(normalizedDeviceCoords.x, normalizedDeviceCoords.y, -1.0f, 1.0f);
+    glm::vec4 eyeCoords = toEyeSpace(clipCoords);
+    glm::vec3 worldCoords = toWorldSpace(eyeCoords);
+    return glm::normalize(worldCoords);
+}
+
+glm::vec2 MousePicker::getNormalizedDeviceCoords(float mouseX, float mouseY) {
+    float x = (2.f * mouseX) / static_cast<float>(Application::getInstance().getWindow().GetWidth()) - 1.f;
+    float y = (2.f * mouseY) / static_cast<float>(Application::getInstance().getWindow().GetHeight()) - 1.f;
+    return {x, y};
+}
+
+glm::vec4 MousePicker::toEyeSpace(const glm::vec4 clipCoords) const {
+    glm::mat4 inverseProjectionMatrix = glm::inverse(projectionMatrix);
+    glm::vec4 eyeCoords = inverseProjectionMatrix * clipCoords;
+    return {eyeCoords.x, eyeCoords.y, -1.0f, 0.0f};
+}
+
+glm::vec3 MousePicker::toWorldSpace(glm::vec4 eyeCoords) const {
+    glm::mat4 inverseViewMatrix = glm::inverse(viewMatrix);
+    glm::vec4 worldCoords = inverseViewMatrix * eyeCoords;
+    return {worldCoords.x, worldCoords.y, worldCoords.z};
+}

src/engine/platform/glfw/MousePicker.h

@@ -0,0 +1,36 @@
+//
+// Created by sebastian on 07.02.26.
+//
+
+#ifndef MOUSEPICKER_H
+#define MOUSEPICKER_H
+#include "glm/mat4x4.hpp"
+#include "glm/vec3.hpp"
+
+class Camera;
+
+class MousePicker {
+private:
+    glm::vec3 currentRay = glm::vec3(0.0f);
+    glm::mat4 projectionMatrix;
+    glm::mat4 viewMatrix;
+
+    glm::vec3 calculateMouseRay();
+
+    static glm::vec2 getNormalizedDeviceCoords(float mouseX, float mouseY);
+    [[nodiscard]] glm::vec4 toEyeSpace(glm::vec4 clipCoords) const;
+    [[nodiscard]] glm::vec3 toWorldSpace(glm::vec4 eyeCoords) const;
+
+public:
+    MousePicker(const glm::mat4 &projectionMatrix, const glm::mat4 &viewMatrix) : projectionMatrix(projectionMatrix), viewMatrix(viewMatrix) {};
+
+    [[nodiscard]] glm::vec3 getCurrentRay() const {
+        return currentRay;
+    }
+
+    void update(const Camera& camera);
+};
+
+
+
+#endif //MOUSEPICKER_H

src/engine/renderer/Renderer.h

@@ -22,6 +22,7 @@ public:
     };
     void prepare(const ::Camera &camera, const Light& light);
     void renderFrame(const ::Entity &entity, const ::Camera &camera, const Light& light);
+    [[nodiscard]] glm::mat4 getProjectionMatrix() const {return projectionMatrix;}
 private:
     void renderRawModel(const Entity &entity);
     StaticShader staticShader;