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 Graphic;
class WalkingCharacter;
class Process;
struct Task;

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

class Camera {
public:
    static Camera *create();
    virtual ~Camera();
    virtual Math::Angle rotation() const = 0;
    virtual float scale() const = 0;

    virtual void preUpdate() = 0;
    virtual void update() = 0;
    virtual void setRoomBounds(Graphic &background) = 0;
    virtual void setFollow(WalkingCharacter *target) = 0;
    virtual void onChangedRoom(bool resetCamera) = 0;
    virtual void onTriggeredDoor(WalkingCharacter *target) = 0;
    virtual void onTriggeredDoor(Common::Point fixedPosition) = 0;
    virtual void onScriptChangedCharacter(MainCharacterKind kind) = 0;
    virtual void onUserChangedCharacter() = 0;
    virtual void onOpenMenu() = 0;
    virtual void onCloseMenu() = 0;
    virtual void syncGame(Common::Serializer &s) = 0;

    Math::Vector3d transform2Dto3D(Math::Vector3d v) const;
    Math::Vector3d transform3Dto2D(Math::Vector3d v) const;
    Common::Point transform3Dto2D(Common::Point p) const;

protected:
    Math::Vector3d setAppliedCenter(Math::Vector3d center);
    void setupMatricesAround(Math::Vector3d center);

    float _roomScale = 1.0f;
    Math::Vector2d
        _roomMin = Math::Vector2d(-10000, -10000),
        _roomMax = Math::Vector2d(10000, 10000);
    Math::Vector3d _appliedCenter;
    Math::Matrix4
        _mat3Dto2D,
        _mat2Dto3D;
};

class CameraV1 : public Camera {
public:
    Math::Angle rotation() const override;
    float scale() const override;

    void preUpdate() override;
    void update() override;
    void setRoomBounds(Graphic &background) override;
    void setFollow(WalkingCharacter *target) override;
    void onChangedRoom(bool resetCamera) override;
    void onTriggeredDoor(WalkingCharacter *target) override;
    void onTriggeredDoor(Common::Point fixedPosition) override;
    void onScriptChangedCharacter(MainCharacterKind kind) override;
    void onUserChangedCharacter() override;
    void onOpenMenu() override;
    void onCloseMenu() override;
    void syncGame(Common::Serializer &s) override;
    void lerpOrSet(Common::Point target, int32 mode);

    Task *disguise(Process &process, int32 duration);

protected:
    friend struct CamV1DisguiseTask;
    void updateLerping(Math::Vector3d &newCenter, float deltaTime, float speed);

    WalkingCharacter *_followTarget = nullptr;
    Math::Vector3d
        _usedCenter, // in V2 the used center is not clipped (that would _appliedCenter)
                     // in menus this variable stays in room space and is clipped to the one valid menu pos
                     // as such it acts like the state backup in CameraV3
        _target;
    bool _isLerping = false;
    float _lerpSpeed = 0.0f;
    uint32 _lastUpdateTime = 0;
};

// V2 is so similar that most can be reused from V1
class CameraV2 final : public CameraV1 {
public:
    void update() override;
    void setRoomBounds(Graphic &background) override;
    void setFollow(WalkingCharacter *target) override;
};

class CameraV3 final : public Camera {
public:
    Math::Angle rotation() const override;
    float scale() const override;

    void preUpdate() override;
    void update() override;
    void setRoomBounds(Graphic &background) override;
    void setFollow(WalkingCharacter *target) override;
    void setFollow(WalkingCharacter *target, bool catchup);
    void onChangedRoom(bool resetCamera) override;
    void onTriggeredDoor(WalkingCharacter *target) override;
    void onTriggeredDoor(Common::Point fixedPosition) override;
    void onScriptChangedCharacter(MainCharacterKind kind) override;
    void onUserChangedCharacter() override;
    void onOpenMenu() override;
    void onCloseMenu() override;
    void syncGame(Common::Serializer &s) override;

    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;

    void resetRotationAndScale();
    void setPosition(Math::Vector2d v);
    void setPosition(Math::Vector3d v);
    void backup(uint slot);
    void restore(uint slot);
    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;
    Math::Vector2d _shake;
};

}

#endif // ALCACHOFA_CAMERA_H