vectozavr-shooter/engine/Object.cpp

//
// Created by Иван Ильин on 15.03.2021.
//

#include "Object.h"
#include "Matrix4x4.h"

void Object::transform(const Matrix4x4 &t) {
    _transformMatrix = t * _transformMatrix;

    for (auto &[attachedName, attachedObject] : _attachedObjects) {
        if (!attachedObject.expired()) {
            attachedObject.lock()->transformRelativePoint(position(), t);
        }
    }
}

void Object::transformRelativePoint(const Vec3D &point, const Matrix4x4 &transform) {

    // translate object in new coordinate system (connected with point)
    _transformMatrix = Matrix4x4::Translation(position() - point) * _transformMatrix;
    // transform object in the new coordinate system
    _transformMatrix = transform * _transformMatrix;
    // translate object back in self connected coordinate system
    _position = _transformMatrix.w() + point;
    _transformMatrix = Matrix4x4::Translation(-_transformMatrix.w()) * _transformMatrix;

    for (auto &[attachedName, attachedObject] : _attachedObjects) {
        if (!attachedObject.expired()) {
            attachedObject.lock()->transformRelativePoint(point, transform);
        }
    }
}

void Object::translate(const Vec3D &dv) {

    _position = _position + dv;

    for (auto &[attachedName, attachedObject] : _attachedObjects) {
        if (!attachedObject.expired()) {
            attachedObject.lock()->translate(dv);
        }
    }
}

void Object::scale(const Vec3D &s) {
    transform(Matrix4x4::Scale(s));
}

void Object::rotate(const Vec3D &r) {
    _angle = _angle + r;

    // TODO: when you rotate body _angle is changed only for this body but all attached objects have incorrect _angle
    Matrix4x4 rotationMatrix = Matrix4x4::RotationZ(r.z()) * Matrix4x4::RotationY(r.y()) * Matrix4x4::RotationX(r.z());
    transform(rotationMatrix);
}

void Object::rotate(const Vec3D &v, double rv) {
    transform(Matrix4x4::Rotation(v, rv));
}

void Object::rotateRelativePoint(const Vec3D &s, const Vec3D &r) {
    transformRelativePoint(s, Matrix4x4::Rotation(r));
}

void Object::rotateRelativePoint(const Vec3D &s, const Vec3D &v, double r) {
    transformRelativePoint(s, Matrix4x4::Rotation(v, r));
}

void Object::rotateLeft(double rl) {
    _angleLeftUpLookAt = Vec3D{_angleLeftUpLookAt.x() + rl,
                               _angleLeftUpLookAt.y(),
                               _angleLeftUpLookAt.z()};

    rotate(left(), rl);
}

void Object::rotateUp(double ru) {
    _angleLeftUpLookAt = Vec3D{_angleLeftUpLookAt.x(),
                               _angleLeftUpLookAt.y() + ru,
                               _angleLeftUpLookAt.z()};

    rotate(up(), ru);
}

void Object::rotateLookAt(double rlAt) {
    _angleLeftUpLookAt = Vec3D{_angleLeftUpLookAt.x(),
                               _angleLeftUpLookAt.y(),
                               _angleLeftUpLookAt.z() + rlAt};
    rotate(lookAt(), rlAt);
}

void Object::translateToPoint(const Vec3D &point) {
    translate(point - position());
}

void Object::rotateToAngle(const Vec3D &v) {
    rotate(v - _angle);
}

std::shared_ptr<Object> Object::attached(const ObjectNameTag &tag) {
    if (_attachedObjects.count(tag) == 0 || _attachedObjects.find(tag)->second.expired()) {
        return nullptr;
    }
    return _attachedObjects.find(tag)->second.lock();
}

bool Object::checkIfAttached(Object *obj) {
    for (const auto&[nameTag, attachedObject] : _attachedObjects) {
        if (obj == attachedObject.lock().get() || attachedObject.lock()->checkIfAttached(obj)) {
            return true;
        }
    }
    return false;
}

void Object::attach(std::shared_ptr<Object> object) {
    if (this != object.get()) {
        if (!object->checkIfAttached(this)) {
            _attachedObjects.emplace(object->name(), object);
        } else {
            throw std::invalid_argument{"Object::attach: You tried to create infinite recursive call chains"};
        }
    } else {
        throw std::invalid_argument{"Object::attach: You cannot attach object to itself"};
    }
}

void Object::unattach(const ObjectNameTag &tag) {
    _attachedObjects.erase(tag);
}

// OpenGL function
GLfloat *Object::glView() const {
    auto *v = (GLfloat *) malloc(4 * 4 * sizeof(GLfloat));

    v[0] = -(GLfloat) left().x();
    v[4] = -(GLfloat) left().y();
    v[8] = -(GLfloat) left().z();
    v[12] = (GLfloat) position().dot(left());

    v[1] = (GLfloat) up().x();
    v[5] = (GLfloat) up().y();
    v[9] = (GLfloat) up().z();
    v[13] = -(GLfloat) position().dot(up());

    v[2] = -(GLfloat) lookAt().x();
    v[6] = -(GLfloat) lookAt().y();
    v[10] = -(GLfloat) lookAt().z();
    v[14] = (GLfloat) position().dot(lookAt());

    v[3] = (GLfloat) 0.0f;
    v[7] = (GLfloat) 0.0f;
    v[11] = (GLfloat) 0.0f;
    v[15] = (GLfloat) 1.0f;

    return v;
}

GLfloat *Object::glModel() const {
    auto *m = (GLfloat *) malloc(4 * 4 * sizeof(GLfloat));

    m[0] = (GLfloat) left().x();
    m[4] = (GLfloat) up().x();
    m[8] = (GLfloat) lookAt().x();
    m[12] = (GLfloat) position().x();

    m[1] = (GLfloat) left().y();
    m[5] = (GLfloat) up().y();
    m[9] = (GLfloat) lookAt().y();
    m[13] = (GLfloat) position().y();

    m[2] = (GLfloat) left().z();
    m[6] = (GLfloat) up().z();
    m[10] = (GLfloat) lookAt().z();
    m[14] = (GLfloat) position().z();

    m[3] = (GLfloat) 0.0f;
    m[7] = (GLfloat) 0.0f;
    m[11] = (GLfloat) 0.0f;
    m[15] = (GLfloat) 1.0f;

    return m;
}

Object::~Object() {
    _attachedObjects.clear();
}