restructure v2

engine/Backend/Camera.cpp

@@ -0,0 +1,107 @@
+
+#include "Camera.h"
+
+#include <glm/gtc/matrix_transform.hpp>
+
+// constructor with vectors
+Camera::Camera(glm::vec3 newPosition, glm::vec3 up, float newYaw, float newPitch) : front(glm::vec3(0.0f, 0.0f, -1.0f)), movementSpeed(SPEED), mouseSensitivity(SENSITIVITY), zoom(ZOOM)
+{
+    position = newPosition;
+    worldUp = up;
+    yaw = newYaw;
+    pitch = newPitch;
+    updateCameraVectors();
+}
+// constructor with scalar values
+Camera::Camera(float posX, float posY, float posZ, float upX, float upY, float upZ, float newYaw, float newPitch) : front(glm::vec3(0.0f, 0.0f, -1.0f)), movementSpeed(SPEED), mouseSensitivity(SENSITIVITY), zoom(ZOOM)
+{
+    position = glm::vec3(posX, posY, posZ);
+    worldUp = glm::vec3(upX, upY, upZ);
+    yaw = newYaw;
+    pitch = newPitch;
+    updateCameraVectors();
+}
+
+// returns the view matrix calculated using Euler Angles and the LookAt Matrix
+glm::mat4 Camera::GetViewMatrix()
+{
+    return glm::lookAt(position, position + front, up);
+}
+
+// processes input received from any keyboard-like input system. Accepts input parameter in the form of camera defined ENUM (to abstract it from windowing systems)
+void Camera::processKeyboard(Camera_Movement direction, float deltaTime)
+{
+    float velocity = movementSpeed * deltaTime;
+    if (sprinting)
+        velocity *= 8;
+
+    if (direction == FORWARD)
+        position += front * velocity;
+    if (direction == BACKWARD)
+        position -= front * velocity;
+    if (direction == LEFT)
+        position -= right * velocity;
+    if (direction == RIGHT)
+        position += right * velocity;
+    if (direction == SPRINT)
+        sprinting = !sprinting;
+}
+
+// processes input received from a mouse input system. Expects the offset value in both the x and y direction.
+void Camera::processMouseMovement(float xoffset, float yoffset, GLboolean constrainPitch)
+{
+    xoffset *= mouseSensitivity;
+    yoffset *= mouseSensitivity;
+
+    yaw   += xoffset;
+    pitch += yoffset;
+
+    // make sure that when pitch is out of bounds, screen doesn't get flipped
+    if (constrainPitch)
+    {
+        if (pitch > 89.0f)
+            pitch = 89.0f;
+
+        if (pitch < -89.0f)
+            pitch = -89.0f;
+    }
+
+    // update Front, Right and Up Vectors using the updated Euler angles
+    updateCameraVectors();
+}
+
+// processes input received from a mouse scroll-wheel event. Only requires input on the vertical wheel-axis
+void Camera::processMouseScroll(float yoffset)
+{
+    zoom -= (float)yoffset;
+    if (zoom < 1.0f)
+        zoom = 1.0f;
+    if (zoom > 45.0f)
+        zoom = 45.0f;
+}
+
+void Camera::Update(Shader shader, int screenWidth, int screenHeight)
+{
+    glm::mat4 projection = glm::perspective(glm::radians(zoom), (float)screenWidth / (float)screenHeight, 0.1f, 100.0f);
+
+    shader.setMat4("projection", projection);
+    shader.setMat4("view", GetViewMatrix());
+    shader.setVec3("viewPos", position);
+}
+
+// calculates the front vector from the Camera's (updated) Euler Angles
+void Camera::updateCameraVectors()
+{
+    // calculate the new Front vector
+    glm::vec3 newFront;
+    newFront.x = cos(glm::radians(yaw)) * cos(glm::radians(pitch));
+    newFront.y = sin(glm::radians(pitch));
+    newFront.z = sin(glm::radians(yaw)) * cos(glm::radians(pitch));
+    front = glm::normalize(newFront);
+
+    // also re-calculate the Right and Up vector
+    right = glm::normalize(glm::cross(front, worldUp));  // normalize the vectors, because their length gets closer to 0 the more you look up or down which results in slower movement.
+    up    = glm::normalize(glm::cross(right, front));
+}
+
+