directx - 在 SharpDx 中保存为 png

Question

我在 Direct2D 下使用 SharpDx 开发 Metro 应用程序。我使用 deviceContext 画了一些图片。如何将图片保存为 png 文件？

Answer 1

解决方案:

  public class Direct2DImageEncoder
  {
    private readonly Direct2DFactoryManager factoryManager;
    private readonly Bitmap wicBitmap;
    private readonly WicRenderTarget renderTarget;

    private readonly int imageWidth, imageHeight;

    public Direct2DImageEncoder(int imageWidth, int imageHeight, int imageDpi)
    {
      this.imageWidth = imageWidth;
      this.imageHeight = imageHeight;      

      factoryManager = new Direct2DFactoryManager();

      wicBitmap = new Bitmap(factoryManager.WicFactory, imageWidth, imageHeight, SharpDX.WIC.PixelFormat.Format32bppBGR, BitmapCreateCacheOption.CacheOnLoad);
      var renderTargetProperties = new RenderTargetProperties(RenderTargetType.Default, new PixelFormat(Format.Unknown, AlphaMode.Unknown), imageDpi, imageDpi, RenderTargetUsage.None, FeatureLevel.Level_DEFAULT);
      renderTarget = new WicRenderTarget(factoryManager.D2DFactory, wicBitmap, renderTargetProperties);
      renderTarget.BeginDraw();
      renderTarget.Clear(Colors.White);
    }

    public void Save(Stream systemStream, Direct2DImageFormat format)
    {
      renderTarget.EndDraw();

      var stream = new WICStream(factoryManager.WicFactory, systemStream);
      var encoder = new BitmapEncoder(factoryManager.WicFactory, Direct2DConverter.ConvertImageFormat(format));
      encoder.Initialize(stream);

      var bitmapFrameEncode = new BitmapFrameEncode(encoder);
      bitmapFrameEncode.Initialize();
      bitmapFrameEncode.SetSize(imageWidth, imageHeight);
      bitmapFrameEncode.PixelFormat = SharpDX.WIC.PixelFormat.FormatDontCare;
      bitmapFrameEncode.WriteSource(wicBitmap);

      bitmapFrameEncode.Commit();
      encoder.Commit();

      bitmapFrameEncode.Dispose();
      encoder.Dispose();
      stream.Dispose();      
    }   
  }

  public class Direct2DFactoryManager
  {
    private readonly SharpDX.WIC.ImagingFactory wicFactory;
    private readonly SharpDX.Direct2D1.Factory d2DFactory;
    private readonly SharpDX.DirectWrite.Factory dwFactory;

    public Direct2DFactoryManager()
    {
      wicFactory = new SharpDX.WIC.ImagingFactory();
      d2DFactory = new SharpDX.Direct2D1.Factory();
      dwFactory = new SharpDX.DirectWrite.Factory();
    }

    public SharpDX.WIC.ImagingFactory WicFactory
    {
      get
      {
        return wicFactory;
      }
    }

    public SharpDX.Direct2D1.Factory D2DFactory
    {
      get
      {
        return d2DFactory;
      }
    }

    public SharpDX.DirectWrite.Factory DwFactory
    {
      get
      {
        return dwFactory;
      }
    }
  }

  public enum Direct2DImageFormat
  {
    Png, Gif, Ico, Jpeg, Wmp, Tiff, Bmp
  }

  public class Direct2DConverter
  {
    public static Guid ConvertImageFormat(Direct2DImageFormat format)
    {
      switch (format)
      {
        case Direct2DImageFormat.Bmp:
          return ContainerFormatGuids.Bmp;
        case Direct2DImageFormat.Ico:
          return ContainerFormatGuids.Ico;
        case Direct2DImageFormat.Gif:
          return ContainerFormatGuids.Gif;
        case Direct2DImageFormat.Jpeg:
          return ContainerFormatGuids.Jpeg;
        case Direct2DImageFormat.Png:
          return ContainerFormatGuids.Png;
        case Direct2DImageFormat.Tiff:
          return ContainerFormatGuids.Tiff;
        case Direct2DImageFormat.Wmp:
          return ContainerFormatGuids.Wmp;
      }
      throw new NotSupportedException();
    }

    #endregion
  }

您应该使用renderTarget的方法进行绘制