citra_qt: Add support for game desktop shortcuts

src/citra_qt/util/util.cpp

@@ -6,6 +6,12 @@
 #include <cmath>
 #include <QPainter>
 #include "citra_qt/util/util.h"
+#include "core/loader/smdh.h"
+
+#ifdef _WIN32
+#include <windows.h>
+#include "common/file_util.h"
+#endif
 
 QFont GetMonospaceFont() {
     QFont font(QStringLiteral("monospace"));
@@ -36,3 +42,120 @@ QPixmap CreateCirclePixmapFromColor(const QColor& color) {
     painter.drawEllipse({circle_pixmap.width() / 2.0, circle_pixmap.height() / 2.0}, 7.0, 7.0);
     return circle_pixmap;
 }
+
+QPixmap GetQPixmapFromSMDH(std::vector<u8>& smdh_data) {
+    Loader::SMDH smdh;
+    std::memcpy(&smdh, smdh_data.data(), sizeof(Loader::SMDH));
+
+    bool large = true;
+    std::vector<u16> icon_data = smdh.GetIcon(large);
+    const uchar* data = reinterpret_cast<const uchar*>(icon_data.data());
+    int size = large ? 48 : 24;
+    QImage icon(data, size, size, QImage::Format::Format_RGB16);
+    return QPixmap::fromImage(icon);
+}
+
+bool SaveIconToFile(const std::filesystem::path& icon_path, const QImage& image) {
+#if defined(WIN32)
+#pragma pack(push, 2)
+    struct IconDir {
+        WORD id_reserved;
+        WORD id_type;
+        WORD id_count;
+    };
+
+    struct IconDirEntry {
+        BYTE width;
+        BYTE height;
+        BYTE color_count;
+        BYTE reserved;
+        WORD planes;
+        WORD bit_count;
+        DWORD bytes_in_res;
+        DWORD image_offset;
+    };
+#pragma pack(pop)
+
+    const QImage source_image = image.convertToFormat(QImage::Format_RGB32);
+    constexpr std::array<int, 7> scale_sizes{256, 128, 64, 48, 32, 24, 16};
+    constexpr int bytes_per_pixel = 4;
+
+    const IconDir icon_dir{
+        .id_reserved = 0,
+        .id_type = 1,
+        .id_count = static_cast<WORD>(scale_sizes.size()),
+    };
+
+    FileUtil::IOFile icon_file(icon_path.string(), "wb");
+    if (!icon_file.IsOpen()) {
+        return false;
+    }
+
+    if (!icon_file.WriteBytes(&icon_dir, sizeof(IconDir))) {
+        return false;
+    }
+
+    std::size_t image_offset = sizeof(IconDir) + (sizeof(IconDirEntry) * scale_sizes.size());
+    for (std::size_t i = 0; i < scale_sizes.size(); i++) {
+        const int image_size = scale_sizes[i] * scale_sizes[i] * bytes_per_pixel;
+        const IconDirEntry icon_entry{
+            .width = static_cast<BYTE>(scale_sizes[i]),
+            .height = static_cast<BYTE>(scale_sizes[i]),
+            .color_count = 0,
+            .reserved = 0,
+            .planes = 1,
+            .bit_count = bytes_per_pixel * 8,
+            .bytes_in_res = static_cast<DWORD>(sizeof(BITMAPINFOHEADER) + image_size),
+            .image_offset = static_cast<DWORD>(image_offset),
+        };
+        image_offset += icon_entry.bytes_in_res;
+        if (!icon_file.WriteBytes(&icon_entry, sizeof(icon_entry))) {
+            return false;
+        }
+    }
+
+    for (std::size_t i = 0; i < scale_sizes.size(); i++) {
+        const QImage scaled_image = source_image.scaled(
+            scale_sizes[i], scale_sizes[i], Qt::IgnoreAspectRatio, Qt::SmoothTransformation);
+        const BITMAPINFOHEADER info_header{
+            .biSize = sizeof(BITMAPINFOHEADER),
+            .biWidth = scaled_image.width(),
+            .biHeight = scaled_image.height() * 2,
+            .biPlanes = 1,
+            .biBitCount = bytes_per_pixel * 8,
+            .biCompression = BI_RGB,
+            .biSizeImage{},
+            .biXPelsPerMeter{},
+            .biYPelsPerMeter{},
+            .biClrUsed{},
+            .biClrImportant{},
+        };
+
+        if (!icon_file.WriteBytes(&info_header, sizeof(info_header))) {
+            return false;
+        }
+
+        for (int y = 0; y < scaled_image.height(); y++) {
+            const auto* line = scaled_image.scanLine(scaled_image.height() - 1 - y);
+            std::vector<u8> line_data(scaled_image.width() * bytes_per_pixel);
+            std::memcpy(line_data.data(), line, line_data.size());
+            if (!icon_file.WriteBytes(line_data.data(), line_data.size())) {
+                return false;
+            }
+        }
+    }
+    icon_file.Close();
+
+    return true;
+#elif defined(__linux__) || defined(__FreeBSD__)
+    // Convert and write the icon as a PNG
+    if (!image.save(QString::fromStdString(icon_path.string()))) {
+        LOG_ERROR(Frontend, "Could not write icon as PNG to file");
+    } else {
+        LOG_INFO(Frontend, "Wrote an icon to {}", icon_path.string());
+    }
+    return true;
+#else
+    return false;
+#endif
+}

src/citra_qt/util/util.h

@@ -4,6 +4,7 @@
 
 #pragma once
 
+#include <filesystem>
 #include <QFont>
 #include <QString>
 
@@ -19,3 +20,18 @@ QString ReadableByteSize(qulonglong size);
  * @return QPixmap circle pixmap
  */
 QPixmap CreateCirclePixmapFromColor(const QColor& color);
+
+/**
+ * Gets the game icon from SMDH data.
+ * @param smdh_data SMDH data
+ * @return QPixmap game icon
+ */
+QPixmap GetQPixmapFromSMDH(std::vector<u8>& smdh_data);
+
+/**
+ * Saves a windows icon to a file
+ * @param path The icons path
+ * @param image The image to save
+ * @return bool If the operation succeeded
+ */
+[[nodiscard]] bool SaveIconToFile(const std::filesystem::path& icon_path, const QImage& image);