Combine images with Siv3D

imgcomb.cpp

#include <Siv3D.hpp>
#include <algorithm>

void Main()
{
    Window::SetTitle(L"imgcomb");

    Window::Resize(30 + 240 + 30 + 240 + 30, 500);

    Graphics::SetBackground(Color(240));

    Font font(10, Typeface::Bold);

    GUIStyle guiStyle = GUIStyle::Default;
    guiStyle.font = font;

    GUI gui(guiStyle);
    gui.setTitle(L"Save a combined image");
    gui.setPos(30, 50 + 240 + 30);

    WidgetStyle widgetStyle;
    widgetStyle.font = font;

    gui.add(GUIText::Create(L"image1", widgetStyle));
    gui.add(L"tf-width1", GUITextField::Create(none, widgetStyle));
    gui.add(GUIText::Create(L"x", widgetStyle));
    gui.addln(L"tf-height1", GUITextField::Create(none, widgetStyle));
    gui.add(GUIText::Create(L"image2", widgetStyle));
    gui.add(L"tf-width2", GUITextField::Create(none, widgetStyle));
    gui.add(GUIText::Create(L"x", widgetStyle));
    gui.addln(L"tf-height2", GUITextField::Create(none, widgetStyle));
    gui.add(L"bt-comb-h", GUIButton::Create(L"Holizontally", widgetStyle));
    gui.add(L"bt-comb-v", GUIButton::Create(L"Vertically", widgetStyle));

    Array<Image> image{ Image(240, 240, Palette::White), Image(240, 240, Palette::White) };

    Array<Texture> texture{ Texture(image[0]), Texture(image[1]) };

    const auto setGuiImageSizeText = [&](const int w, const int h, const int imageSide /* 0 or 1 */)
    {
        const Array<String> guiid_w{ L"tf-width1", L"tf-width2" };
        const Array<String> guiid_h{ L"tf-height1", L"tf-height2" };
        gui.textField(guiid_w[imageSide]).setText(Format(w));
        gui.textField(guiid_h[imageSide]).setText(Format(h));
    };

    const auto loadImage = [&](const FilePath& filePath, const int imageSide /* 0 or 1 */)
    {
        image[imageSide] = Image(filePath);
        texture[imageSide] = Texture(image[imageSide]);
        setGuiImageSizeText(image[imageSide].width, image[imageSide].height, imageSide);
    };

    for (int i : step(image.size()))
    {
        setGuiImageSizeText(image[i].width, image[i].height, i);
    }

    while (System::Update())
    {
        font(L"Drag & drop image files").drawCenter(Window::Size().x / 2, 40 / 2, Palette::Black);

        Array<Rect> rect{ Rect(30, 50, 240), Rect(30 + 240 + 30, 50, 240) };

        for (int i : step(rect.size()))
        {
            rect[i].drawShadow({ 5, 5 }, 14.0, 2.0, ColorF(0.0, 0.5));
            rect[i](texture[i]).draw();
            rect[i].drawFrame(0.0, 3.0, Palette::Royalblue);

            Rect label(rect[i].pos, 16);
            label.draw(Palette::White).drawFrame(0.0, 3.0, Palette::Black);
            font(Format(i + 1)).drawCenter(label.center, Palette::Royalblue);
        }

        if (Dragdrop::HasItems())
        {
            const auto items = Dragdrop::GetFilePaths();

            const Point dropPos = Dragdrop::GetPos();

            Array<int> imageSideNum{ 0, 1 };

            if (rect[1].contains(dropPos))
            {
                std::reverse(imageSideNum.begin(), imageSideNum.end());
            }

            for (int i = 0; i < Min((int)items.size(), 2); i++)
            {
                loadImage(items[i], imageSideNum[i]);
            }
        }

        Optional<bool> holizontal = none;
        if (gui.button(L"bt-comb-h").pushed)
        {
            holizontal = true;
        }
        else if (gui.button(L"bt-comb-v").pushed)
        {
            holizontal = false;
        }

        if (holizontal.has_value())
        {
            const auto save = Dialog::GetSaveImage();

            if (save)
            {
                int w1 = Parse<int>(gui.textField(L"tf-width1").text);
                int h1 = Parse<int>(gui.textField(L"tf-height1").text);
                int w2 = Parse<int>(gui.textField(L"tf-width2").text);
                int h2 = Parse<int>(gui.textField(L"tf-height2").text);

                if (holizontal.value())
                {
                    // Horizontally
                    if (h1 == h2)
                    {
                        Image newImage(w1 + w2, h1);
                        image[0].scaled(w1, h1).overwrite(newImage, { 0, 0 });
                        image[1].scaled(w2, h2).overwrite(newImage, { w1, 0 });
                        newImage.save(save.value());
                    }
                }
                else
                {
                    // Vertically
                    if (w1 == w2)
                    {
                        Image newImage(w1, h1 + h2);
                        image[0].scaled(w1, h1).overwrite(newImage, { 0, 0 });
                        image[1].scaled(w2, h2).overwrite(newImage, { 0, h1 });
                        newImage.save(save.value());
                    }
                }
            }
        }
    }
}