camera.cpp

Go to the documentation of this file.

#include "camera.hpp"
 
#include <glm/ext/matrix_clip_space.hpp>
#include <glm/ext/matrix_transform.hpp>
 
sKit::Camera::Camera(float width, float height) {
  projectionMatrix_ =
      glm::perspective<float>(glm::radians(fov_), width / height, near_, far_);
 
  viewMatrix_ = glm::lookAt(pos_, viewOrigin_, up_);
}
 
auto sKit::Camera::getProjectionMatrix() -> glm::mat4 {
  return projectionMatrix_;
}
 
auto sKit::Camera::getViewMatrix() -> glm::mat4 { return viewMatrix_; }
 
auto sKit::Camera::getPos() -> glm::vec3 { return pos_; };
 
auto sKit::Camera::setPos(glm::vec3 pos) -> void {
  pos_ = pos;
  viewMatrix_ = glm::lookAt(pos_, viewOrigin_, up_);
}
 
auto sKit::Camera::update(SDL_Event *event) -> void {
  if (event->type == SDL_EVENT_MOUSE_WHEEL) {
    auto newPos = pos_ + (viewOrigin_ - pos_) * event->wheel.y * 0.1f;
    setPos(newPos);
  }
  if (event->type == SDL_EVENT_MOUSE_MOTION) {
    glm::vec2 mpos;
    auto flags = SDL_GetMouseState(&mpos.x, &mpos.y);
    glm::vec2 dPos = (mpos - lastMousePos_);
    if (flags == SDL_BUTTON_LMASK) {  // drag
      auto roty =
          glm::rotate(glm::mat4(1), glm::radians(-dPos.x), glm::vec3(0, 1, 0));
      auto rot = glm::rotate(roty, glm::radians(-dPos.y), glm::vec3(1, 0, 0));
      setPos(rot * glm::vec4(pos_, 1));
    }
    SDL_GetMouseState(&lastMousePos_.x, &lastMousePos_.y);
  }
};