ladybird/Applications/PaintBrush/ImageEditor.cpp

/*
 * Copyright (c) 2020, Andreas Kling <kling@serenityos.org>
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions are met:
 *
 * 1. Redistributions of source code must retain the above copyright notice, this
 *    list of conditions and the following disclaimer.
 *
 * 2. Redistributions in binary form must reproduce the above copyright notice,
 *    this list of conditions and the following disclaimer in the documentation
 *    and/or other materials provided with the distribution.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
 * DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE
 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
 * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
 * CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
 * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 */

#include "ImageEditor.h"
#include "Image.h"
#include "Layer.h"
#include "LayerModel.h"
#include "Tool.h"
#include <LibGUI/Painter.h>
#include <LibGfx/Palette.h>

namespace PaintBrush {

ImageEditor::ImageEditor()
{
}

void ImageEditor::set_image(RefPtr<Image> image)
{
    m_image = move(image);
    update();
}

void ImageEditor::paint_event(GUI::PaintEvent& event)
{
    GUI::Frame::paint_event(event);

    GUI::Painter painter(*this);
    painter.add_clip_rect(event.rect());
    painter.add_clip_rect(frame_inner_rect());

    painter.translate(frame_thickness(), frame_thickness());
    painter.fill_rect_with_checkerboard(rect(), { 8, 8 }, palette().base().darkened(0.9), palette().base());

    if (m_image) {
        painter.draw_rect(m_image->rect().inflated(2, 2), Color::Black);
        m_image->paint_into(painter, m_image->rect(), m_image->rect());
    }

    if (m_active_layer) {
        painter.draw_rect(m_active_layer->relative_rect().inflated(2, 2), Color::Black);
    }
}

void ImageEditor::second_paint_event(GUI::PaintEvent& event)
{
    if (m_active_tool && m_active_layer)
        m_active_tool->on_second_paint(*m_active_layer, event);
}

static GUI::MouseEvent event_adjusted_for_layer(const GUI::MouseEvent& original_event, const Layer& layer)
{
    auto position_in_active_layer_coordinates = original_event.position().translated(-layer.location());
    return {
        static_cast<GUI::Event::Type>(original_event.type()),
        position_in_active_layer_coordinates, original_event.buttons(),
        original_event.button(),
        original_event.modifiers(),
        original_event.wheel_delta()
    };
}

void ImageEditor::mousedown_event(GUI::MouseEvent& event)
{
    if (!m_active_tool)
        return;

    if (m_active_tool->is_move_tool()) {
        if (auto* other_layer = layer_at(event.position())) {
            set_active_layer(other_layer);
        }
    }

    if (!m_active_layer)
        return;

    auto layer_event = event_adjusted_for_layer(event, *m_active_layer);
    m_active_tool->on_mousedown(*m_active_layer, layer_event, event);
}

void ImageEditor::mousemove_event(GUI::MouseEvent& event)
{
    if (!m_active_layer || !m_active_tool)
        return;
    auto layer_event = event_adjusted_for_layer(event, *m_active_layer);
    m_active_tool->on_mousemove(*m_active_layer, layer_event, event);
}

void ImageEditor::mouseup_event(GUI::MouseEvent& event)
{
    if (!m_active_layer || !m_active_tool)
        return;
    auto layer_event = event_adjusted_for_layer(event, *m_active_layer);
    m_active_tool->on_mouseup(*m_active_layer, layer_event, event);
}

void ImageEditor::keydown_event(GUI::KeyEvent& event)
{
    if (m_active_tool)
        m_active_tool->on_keydown(event);
}

void ImageEditor::keyup_event(GUI::KeyEvent& event)
{
    if (m_active_tool)
        m_active_tool->on_keyup(event);
}

void ImageEditor::set_active_layer(Layer* layer)
{
    if (m_active_layer == layer)
        return;
    m_active_layer = layer;

    if (m_active_layer) {
        size_t index = 0;
        for (; index < m_image->layer_count(); ++index) {
            if (&m_image->layer(index) == layer)
                break;
        }
        if (on_active_layer_change)
            on_active_layer_change(m_image->layer_model().index(index));
    } else {
        if (on_active_layer_change)
            on_active_layer_change({});
    }

    layers_did_change();
}

void ImageEditor::set_active_tool(Tool* tool)
{
    if (m_active_tool == tool)
        return;

    if (m_active_tool)
        m_active_tool->clear();

    m_active_tool = tool;

    if (m_active_tool)
        m_active_tool->setup(*this);
}

void ImageEditor::layers_did_change()
{
    static_cast<LayerModel&>(m_image->layer_model()).update_without_invalidating_indexes();
    update();
}

Color ImageEditor::color_for(GUI::MouseButton button) const
{
    if (button == GUI::MouseButton::Left)
        return m_primary_color;
    if (button == GUI::MouseButton::Right)
        return m_secondary_color;
    ASSERT_NOT_REACHED();
}

Color ImageEditor::color_for(const GUI::MouseEvent& event) const
{
    if (event.buttons() & GUI::MouseButton::Left)
        return m_primary_color;
    if (event.buttons() & GUI::MouseButton::Right)
        return m_secondary_color;
    ASSERT_NOT_REACHED();
}

void ImageEditor::set_primary_color(Color color)
{
    if (m_primary_color == color)
        return;
    m_primary_color = color;
    if (on_primary_color_change)
        on_primary_color_change(color);
}

void ImageEditor::set_secondary_color(Color color)
{
    if (m_secondary_color == color)
        return;
    m_secondary_color = color;
    if (on_secondary_color_change)
        on_secondary_color_change(color);
}

Layer* ImageEditor::layer_at(const Gfx::Point& position)
{
    if (!m_image)
        return nullptr;
    for (ssize_t i = m_image->layer_count() - 1; i >= 0; --i) {
        auto& layer = m_image->layer(i);
        if (layer.relative_rect().contains(position))
            return const_cast<Layer*>(&layer);
    }
    return nullptr;
}

}