勉强完成延迟很高

render_2D/render_2D/base/Frame_2D.cpp

@@ -30,9 +30,13 @@ struct Frame_2D::Private {
 };
 Frame_2D::Frame_2D(Frame_Identity identity, Pixel_Format output_format)
     : Render_Frame(identity), d(std::make_unique<Private>()) {
+    begin(identity, output_format);
+}
+void Frame_2D::begin(Frame_Identity identity, Pixel_Format output_format) {
     if (std::ranges::find(supported_pixel_formats, output_format) ==
         supported_pixel_formats.end())
         throw std::invalid_argument("Frame_2D output pixel format is unsupported");
+    Render_Frame::begin(identity);
     d->output_format = output_format;
 }
 Frame_2D::~Frame_2D() = default;

render_2D/render_2D/base/Frame_2D.hpp

@@ -19,6 +19,9 @@ public:
     explicit Frame_2D(Frame_Identity identity,
                       Pixel_Format output_format = native_pixel_format);
     ~Frame_2D() override;
+    /* 保留 Blend2D 图像分配，只重启物理槽承载的新逻辑帧。 */
+    void begin(Frame_Identity identity,
+               Pixel_Format output_format = native_pixel_format);
     [[nodiscard]] Pixel_Format output_format() const noexcept;
     [[nodiscard]] Image_View image() const;
     /* 按本帧声明的输出格式生成连续像素；原生格式只做必要的行打包。 */