Win32 - export bitmap in more clipboard formats #20209
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| using var stream = new MemoryStream(); | ||
| bitmap.Save(stream); | ||
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| return WriteBytesToHGlobal(ref hGlobal, stream.ToArray().AsSpan()); |
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we could probably do here without a copy, there is MemoryStream.GetBuffer(), but it might be larger than you need, so you need to use Length
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Thats probably over-optimization. We are rarely copying images that often to have issues with memory copies. Best to be stable in this case.
| biPlanes = 1, | ||
| biBitCount = (ushort)(bitmap.Format?.BitsPerPixel ?? 0), | ||
| biCompression = 0, | ||
| biSizeImage = (uint)(pixelSize.Width * 4 * Math.Abs(pixelSize.Height)) |
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You are assuming pixel is 4 bytes here but use any BitsPerPixel value you get from the bitmap. These should be made to match (and match the reality). Some of the formats, and especially the ones with transparency cannot be supported using BITMAPINFOHEADER, you need V5 header. The main benefit of using HBITMAP is that it can support more pixel formats than CF_DIB.
| public static extern int SetDIBits(IntPtr hdc, IntPtr hbm, uint start, uint cLines, IntPtr lpBits, [In] ref BITMAPINFO lpbmi, uint fuColorUse); | ||
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| [DllImport("gdi32.dll")] | ||
| public static extern int SetDIBits(IntPtr hdc, IntPtr hbm, uint start, uint cLines, IntPtr lpBits, [In] ref BITMAPINFOHEADER lpbmi, uint fuColorUse); |
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instead of [In] ref you can just do in (and pass it without a qualifier at callsite)
| or ClipboardFormatRegistry.BitmapFormat | ||
| or ClipboardFormatRegistry.PngFormatMimeType | ||
| or ClipboardFormatRegistry.JpegFormatMimeType) | ||
| or ClipboardFormatRegistry.PngFormatMimeType) |
| private static readonly List<(DataFormat Format, ushort Id)> s_formats = []; | ||
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| public static DataFormat PngSystemDataFormat = DataFormat.FromSystemName<Bitmap>("PNG" , AppPrefix); | ||
| public static DataFormat PngDataFormat = DataFormat.FromSystemName<Bitmap>(PngFormatMimeType , AppPrefix); |
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The names are not too helpful, would prefer PngDataFormat for PNG and PngMimeDataFormat for image/png.
| public const string DibFormat = "CF_DIB"; | ||
| private static readonly List<(DataFormat Format, ushort Id)> s_formats = []; | ||
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| public static DataFormat PngSystemDataFormat = DataFormat.FromSystemName<Bitmap>("PNG" , AppPrefix); |
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why is image/png format extracted into const and PNG not?
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You can test this PR using the following package version. |
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You can test this PR using the following package version. |
| bitmap.CopyPixels(new PixelRect(pixelSize), (IntPtr)bytes, buffer.Length, stride); | ||
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| var infoHeader = new BITMAPINFOHEADER() | ||
| if (!isV5) |
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it is not V5 you would need to ensure the bitmap is one of the supported formats
| bV5Height = -pixelSize.Height, | ||
| bV5Planes = 1, | ||
| bV5BitCount = (ushort)bpp, | ||
| bV5Compression = BitmapCompressionMode.BI_BITFIELDS, |
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only valid for 16bpp and 32bpp, must be BI_RGB otherwise
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for 555 bitmaps, either provide filter or use BI_RGB
| bV5GreenMask = GetGreenMask(bitmap), | ||
| bV5AlphaMask = GetAlphaMask(bitmap), | ||
| bV5CSType = BitmapColorSpace.LCS_sRGB, | ||
| bV5Intent = BitmapIntent.LCS_GM_BUSINESS, |
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why business here but colorimetric for dib?
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You can test this PR using the following package version. |
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You can test this PR using the following package version. |
What does the pull request do?
Adds more image format when bitmaps are exported to clipboard, namely the png and native bitmap(CF_BITMAP) formats, on Windows.
Due to some cleanup, jpeg format is removed from the input preferred formats, i.e. formats we read from the clipboard. This support may be added back later.
What is the current behavior?
We currently export bitmaps using the CF_DIB format. Some apps may not support this format, and thus can't read our bitmaps.
With this PR, our bitmaps are exported in the following formats:
image/png,PNG,CF_DIB,CF_BITMAP, in that order.What is the updated/expected behavior with this PR?
How was the solution implemented (if it's not obvious)?
Checklist
Breaking changes
Obsoletions / Deprecations
Fixed issues
Fixes #20183