infinipaint/src/CoordSpaceHelperTransform.hpp

/*  
 * InfiniPaint
 * Copyright (C) 2025-2026 Yousef Khadadeh
 *
 * This program is free software: you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation, either version 3 of the License, or
 * (at your option) any later version.
 *
 * This program 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 General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program.  If not, see <https://www.gnu.org/licenses/>.
 */

#pragma once
#include "SharedTypes.hpp"
#include <Helpers/Serializers.hpp>
#include <array>
#include <Helpers/SCollision.hpp>
#include "CoordSpaceHelper.hpp"

#ifndef IS_SERVER
#include "include/core/SkMatrix.h"
#include "include/core/SkCanvas.h"
#endif

class World;
struct DrawData;

class CoordSpaceHelperTransform {
    public:
        CoordSpaceHelperTransform();
        CoordSpaceHelperTransform(const WorldVec& translationPos);
        CoordSpaceHelperTransform(const WorldVec& rotatePos, double angle);
        CoordSpaceHelperTransform(const WorldVec& scalePos, const WorldMultiplier& inverseScaleAmount);

        WorldVec from_space_world(const WorldVec& coord) const;
        //WorldVec to_space_world(const WorldVec& coord) const;

        CoordSpaceHelper other_coord_space_to_this_space(const CoordSpaceHelper& other) const;
        CoordSpaceHelper other_coord_space_from_this_space(const CoordSpaceHelper& other) const;

        bool operator==(const CoordSpaceHelperTransform& otherCoords) const;
        bool operator!=(const CoordSpaceHelperTransform& otherCoords) const;

        enum class TransformType {
            NONE,
            TRANSLATE,
            ROTATE,
            SCALE
        };

        bool is_identity();

    private:
        void set_rotation(double newRotation);
        void translate(const WorldVec& translation);
        void rotate_about(const WorldVec& rotatePos, double angle);
        void scale_about(const WorldVec& scalePos, const WorldMultiplier& scaleAmount);

        TransformType transformType = TransformType::NONE;
        WorldVec pos{0, 0}; // rotation center, scale center, or translation value
        WorldMultiplier inverseScale{1};
        double rotation = 0.0;
};

std::ostream& operator<<(std::ostream& os, const CoordSpaceHelperTransform& a);