Crafter.Graphics/src/module/Crafter.Graphics-Camera.cppm

/*
Crafter®.Graphics
Copyright (C) 2025 Catcrafts®
Catcrafts.net

This library is free software; you can redistribute it and/or
modify it under the terms of the GNU Lesser General Public
License as published by the Free Software Foundation; either
version 3.0 of the License, or (at your option) any later version.

This library is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
Lesser General Public License for more details.

You should have received a copy of the GNU Lesser General Public
License along with this library; if not, write to the Free Software
Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301 USA
*/

module;

#include <cstdint>

export module Crafter.Graphics:Camera;
import :VulkanBuffer;
import Crafter.Math;
import Crafter.Event;

namespace Crafter {
    /**
    * @brief 3D camera with projection and view matrices
    * @example examples/VulkanCube/main.cpp
    */
    export class Camera {
    public:
        MatrixRowMajor<float, 4, 4, 1> projection;
        MatrixRowMajor<float, 4, 4, 1> view;
        MatrixRowMajor<float, 4, 4, 1> projectionView;
        Event<void> onUpdate;
        /**
        * @param fov Field of view in radians.
        * @param aspectRatio Aspect ratio of the camera (width / height).
        * @param near Near clipping plane.
        * @param far Far clipping plane.
        * @example examples/VulkanCube/main.cpp
        */
        Camera(float fov, float aspectRatio, float near, float far);

        /**
        * @brief calculates the projectionView matrix by multiplying the projection and view matricies.
        */
        void Update();

        /**
        * @brief Converts screen-space coordinates to a 3D world-space ray.
        * @param x The x-coordinate on the screen (in pixels).
        * @param y The y-coordinate on the screen (in pixels).
        * @return A normalized 3D direction vector representing the ray from the camera.
        */
        Vector<float, 3> ToRay(uint32_t x, uint32_t y);
    };
}