camera.h

/* ScummVM - Graphic Adventure Engine
 *
 * ScummVM is the legal property of its developers, whose names
 * are too numerous to list here. Please refer to the COPYRIGHT
 * file distributed with this source distribution.
 *
 * 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 <http://www.gnu.org/licenses/>.
 *
 */

#ifndef ALCACHOFA_CAMERA_H
#define ALCACHOFA_CAMERA_H

#include "alcachofa/common.h"
#include "math/matrix4.h"

namespace Alcachofa {

class WalkingCharacter;
class Process;
struct Task;

static constexpr const int16_t kBaseScale = 300;
static constexpr const float kInvBaseScale = 1.0f / kBaseScale;

class Camera {
public:
    inline Math::Angle rotation() const { return _cur._rotation; }
    inline Math::Vector2d &shake() { return _shake; }
    inline WalkingCharacter *followTarget() { return _followTarget; }

    void update();
    Math::Vector3d transform2Dto3D(Math::Vector3d v) const;
    Math::Vector3d transform3Dto2D(Math::Vector3d v) const;
    Common::Point transform3Dto2D(Common::Point p) const;
    void resetRotationAndScale();
    void setRoomBounds(Common::Point bgSize, int16 bgScale);
    void setFollow(WalkingCharacter *target, bool catchUp = false);
    void setPosition(Math::Vector2d v);
    void setPosition(Math::Vector3d v);
    void backup(uint slot);
    void restore(uint slot);
    void syncGame(Common::Serializer &s);

    Task *lerpPos(Process &process,
        Math::Vector2d targetPos,
        int32 duration, EasingType easingType);
    Task *lerpPos(Process &process,
        Math::Vector3d targetPos,
        int32 duration, EasingType easingType);
    Task *lerpPosZ(Process &process,
        float targetPosZ,
        int32 duration, EasingType easingType);
    Task *lerpScale(Process &process,
        float targetScale,
        int32 duration, EasingType easingType);
    Task *lerpRotation(Process &process,
        float targetRotation,
        int32 duration, EasingType easingType);
    Task *lerpPosScale(Process &process,
        Math::Vector3d targetPos, float targetScale,
        int32 duration, EasingType moveEasingType, EasingType scaleEasingType);
    Task *waitToStop(Process &process);
    Task *shake(Process &process, Math::Vector2d amplitude, Math::Vector2d frequency, int32 duration);

private:
    friend struct CamLerpTask;
    friend struct CamLerpPosTask;
    friend struct CamLerpScaleTask;
    friend struct CamLerpPosScaleTask;
    friend struct CamLerpRotationTask;
    friend struct CamShakeTask;
    friend struct CamWaitToStopTask;
    friend struct CamSetInactiveAttributeTask;
    Math::Vector3d setAppliedCenter(Math::Vector3d center);
    void setupMatricesAround(Math::Vector3d center);
    void updateFollowing(float deltaTime);

    struct State {
        Math::Vector3d _usedCenter = Math::Vector3d(512, 384, 0);
        float
            _scale = 1.0f,
            _speed = 0.0f,
            _maxSpeedFactor = 230.0f;
        Math::Angle _rotation;
        bool _isBraking = false;
        bool _isFollowingTarget = false;

        void syncGame(Common::Serializer &s);
    };

    static constexpr uint kStateBackupCount = 2;
    State _cur, _backups[kStateBackupCount];
    WalkingCharacter *_followTarget = nullptr;
    uint32 _lastUpdateTime = 0;
    bool _isChanging = false,
        _catchUp = false;
    float _roomScale = 1.0f;
    Math::Vector2d
        _roomMin = Math::Vector2d(-10000, -10000),
        _roomMax = Math::Vector2d(10000, 10000),
        _shake;
    Math::Vector3d _appliedCenter;
    Math::Matrix4
        _mat3Dto2D,
        _mat2Dto3D;
};

}

#endif // ALCACHOFA_CAMERA_H