View.cpp

Go to the documentation of this file.

/*
 * =====================================================================================
 *
 *       Filename:  View.cpp
 *
 *    Description:
 *
 *        Created:  01/01/2019 21:30:43
 *
 *         Author:  Quentin Bazin, <quent42340@gmail.com>
 *
 * =====================================================================================
 */
#include <cmath>

#define GLM_FORCE_RADIANS
#include <glm/gtc/matrix_transform.hpp>

#include "gk/gl/View.hpp"

namespace gk {

View::View() {
    reset(FloatRect(0, 0, 1000, 1000));
}

View::View(const Vector3f &center, const Vector2f &size) {
    reset(FloatRect(center.xy(), size));
}

View::View(const FloatRect &rectangle) {
    reset(rectangle);
}

void View::setCenter(float x, float y, float z) {
    m_position.x = x;
    m_position.y = y;
    m_position.z = z;

    m_viewTransformUpdated = false;
}

void View::setSize(float width, float height) {
    m_size.x = width;
    m_size.y = height;

    m_transformUpdated = false;
    m_viewTransformUpdated = false;
}

void View::setRotation(float angle) {
    m_rotation = static_cast<float>(fmod(angle, 360));
    if (m_rotation < 0)
        m_rotation += 360.f;

    m_viewTransformUpdated = false;
}

void View::reset(const FloatRect &rectangle) {
    m_position.x = rectangle.x + rectangle.width / 2.f;
    m_position.y = rectangle.y + rectangle.height / 2.f;

    m_size.x = rectangle.width;
    m_size.y = rectangle.height;

    m_rotation = 0;

    m_transformUpdated = false;
}

void View::move(float offsetX, float offsetY, float offsetZ) {
    setCenter(m_position.x + offsetX, m_position.y + offsetY, m_position.z + offsetZ);
}

const Transform &View::getTransform() const {
    if (!m_transformUpdated) {
        m_transform = glm::ortho(0.0f, m_size.x, m_size.y, 0.0f);

        m_transformUpdated = true;
    }

    return m_transform;
}

const Transform &View::getViewTransform() const {
    if (!m_viewTransformUpdated) {
        Transform positionTransform;
        positionTransform.translate(m_size.x / 2.f - m_position.x, m_size.y / 2.f - m_position.y);

        Transform rotationTransform;
        rotationTransform.rotate(m_rotation * M_PI / 180.0f);

        m_viewTransform = positionTransform * rotationTransform;

        // m_viewTransform = Transform::Identity;
        // m_viewTransform.rotate(m_rotation);
        // m_viewTransform.translate(Vector3f{getCenter().x, getCenter().y, 0}
        //      - Vector3f{getSize(), 0.f} / 2.0f);

        m_viewTransformUpdated = true;
    }

    return m_viewTransform;
}

} // namespace gk