kopia lustrzana https://github.com/dl2alf/AirScout
436 wiersze
26 KiB
C#
436 wiersze
26 KiB
C#
using System;
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using System.Runtime.InteropServices;
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namespace Vanara.Interop
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{
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internal static partial class NativeMethods
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{
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/// <summary>The BITMAPINFO structure defines the dimensions and color information for a DIB.</summary>
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/// <remarks>
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/// A DIB consists of two distinct parts: a BITMAPINFO structure describing the dimensions and colors of the
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/// bitmap, and an array of bytes defining the pixels of the bitmap. The bits in the array are packed together,
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/// but each scan line must be padded with zeros to end on a LONG data-type boundary. If the height of the bitmap
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/// is positive, the bitmap is a bottom-up DIB and its origin is the lower-left corner. If the height is
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/// negative, the bitmap is a top-down DIB and its origin is the upper left corner.
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/// <para>
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/// A bitmap is packed when the bitmap array immediately follows the BITMAPINFO header. Packed bitmaps are
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/// referenced by a single pointer. For packed bitmaps, the biClrUsed member must be set to an even number when
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/// using the DIB_PAL_COLORS mode so that the DIB bitmap array starts on a DWORD boundary.
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/// </para>
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/// <para><c>Note</c></para>
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/// <para>
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/// The bmiColors member should not contain palette indexes if the bitmap is to be stored in a file or
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/// transferred to another application.
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/// </para>
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/// <para>
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/// Unless the application has exclusive use and control of the bitmap, the bitmap color table should contain
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/// explicit RGB values.
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/// </para>
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/// </remarks>
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[StructLayout(LayoutKind.Sequential)]
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public struct BITMAPINFO
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{
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/// <summary>A BITMAPINFOHEADER structure that contains information about the dimensions of color format.</summary>
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public BITMAPINFOHEADER bmiHeader;
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/// <summary>
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/// The bmiColors member contains one of the following:
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/// <list type="bullet">
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/// <item>
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/// <description>An array of RGBQUAD. The elements of the array that make up the color table.</description>
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/// </item>
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/// <item>
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/// <description>
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/// An array of 16-bit unsigned integers that specifies indexes into the currently realized logical palette.
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/// This use of bmiColors is allowed for functions that use DIBs. When bmiColors elements contain indexes to
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/// a realized logical palette, they must also call the following bitmap functions: CreateDIBitmap,
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/// CreateDIBPatternBrush, CreateDIBSection (The iUsage parameter of CreateDIBSection must be set to DIB_PAL_COLORS.)
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/// </description>
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/// </item>
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/// </list>
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/// <para>
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/// The number of entries in the array depends on the values of the biBitCount and biClrUsed members of the
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/// BITMAPINFOHEADER structure.
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/// </para>
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/// <para>
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/// The colors in the bmiColors table appear in order of importance. For more information, see the Remarks section.
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/// </para>
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/// </summary>
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[MarshalAsAttribute(UnmanagedType.ByValArray, SizeConst = 1, ArraySubType = UnmanagedType.Struct)]
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public RGBQUAD[] bmiColors;
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/// <summary>
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/// Initializes a new instance of the <see cref="BITMAPINFO"/> structure.
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/// </summary>
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/// <param name="width">The width.</param>
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/// <param name="height">The height.</param>
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/// <param name="bitCount">The bit count.</param>
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public BITMAPINFO(int width, int height, ushort bitCount = 32)
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: this()
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{
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bmiHeader.biSize = Marshal.SizeOf(typeof(BITMAPINFO));
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bmiHeader.biWidth = width;
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bmiHeader.biHeight = height;
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bmiHeader.biPlanes = 1;
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bmiHeader.biBitCount = bitCount;
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bmiHeader.biCompression = BitmapCompressionMode.BI_RGB;
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bmiHeader.biSizeImage = 0; // (uint)width * (uint)height * bitCount / 8;
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}
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}
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/// <summary>The type of compression for a compressed bottom-up bitmap (top-down DIBs cannot be compressed). Used in <see cref="BITMAPINFOHEADER"/>.</summary>
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public enum BitmapCompressionMode : uint
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{
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/// <summary>An uncompressed format.</summary>
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BI_RGB = 0,
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/// <summary>A run-length encoded (RLE) format for bitmaps with 8 bpp. The compression format is a 2-byte format consisting of a count byte followed by a byte containing a color index.</summary>
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BI_RLE8 = 1,
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/// <summary>An RLE format for bitmaps with 4 bpp. The compression format is a 2-byte format consisting of a count byte followed by two word-length color indexes.</summary>
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BI_RLE4 = 2,
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/// <summary>Specifies that the bitmap is not compressed and that the color table consists of three DWORD color masks that specify the red, green, and blue components, respectively, of each pixel. This is valid when used with 16- and 32-bpp bitmaps.</summary>
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BI_BITFIELDS = 3,
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/// <summary>Indicates that the image is a JPEG image.</summary>
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BI_JPEG = 4,
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/// <summary>Indicates that the image is a PNG image.</summary>
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BI_PNG = 5
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}
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/// <summary>The BITMAPINFOHEADER structure contains information about the dimensions and color format of a DIB.</summary>
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[StructLayout(LayoutKind.Sequential)]
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public struct BITMAPINFOHEADER
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{
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/// <summary>The number of bytes required by the structure.</summary>
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public int biSize;
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/// <summary>
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/// The width of the bitmap, in pixels. If biCompression is BI_JPEG or BI_PNG, the biWidth member specifies the width of the decompressed JPEG or PNG
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/// image file, respectively.
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/// </summary>
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public int biWidth;
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/// <summary>
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/// The height of the bitmap, in pixels. If biHeight is positive, the bitmap is a bottom-up DIB and its origin is the lower-left corner. If biHeight
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/// is negative, the bitmap is a top-down DIB and its origin is the upper-left corner.
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/// <para>If biHeight is negative, indicating a top-down DIB, biCompression must be either BI_RGB or BI_BITFIELDS. Top-down DIBs cannot be compressed.</para>
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/// <para>If biCompression is BI_JPEG or BI_PNG, the biHeight member specifies the height of the decompressed JPEG or PNG image file, respectively.</para>
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/// </summary>
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public int biHeight;
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/// <summary>The number of planes for the target device. This value must be set to 1.</summary>
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public ushort biPlanes;
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/// <summary>
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/// The number of bits-per-pixel. The biBitCount member of the BITMAPINFOHEADER structure determines the number of bits that define each pixel and
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/// the maximum number of colors in the bitmap. This member must be one of the following values.
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/// <list type="table">
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/// <listheader>
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/// <term>Value</term>
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/// <description>Meaning</description>
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/// </listheader>
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/// <item>
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/// <term>0</term>
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/// <description>The number of bits-per-pixel is specified or is implied by the JPEG or PNG format.</description>
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/// </item>
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/// <item>
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/// <term>1</term>
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/// <description>
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/// The bitmap is monochrome, and the bmiColors member of BITMAPINFO contains two entries. Each bit in the bitmap array represents a pixel. If the
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/// bit is clear, the pixel is displayed with the color of the first entry in the bmiColors table; if the bit is set, the pixel has the color of the
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/// second entry in the table.
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/// </description>
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/// </item>
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/// <item>
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/// <term>4</term>
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/// <description>
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/// The bitmap has a maximum of 16 colors, and the bmiColors member of BITMAPINFO contains up to 16 entries. Each pixel in the bitmap is represented
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/// by a 4-bit index into the color table. For example, if the first byte in the bitmap is 0x1F, the byte represents two pixels. The first pixel
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/// contains the color in the second table entry, and the second pixel contains the color in the sixteenth table entry.
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/// </description>
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/// </item>
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/// <item>
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/// <term>8</term>
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/// <description>
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/// The bitmap has a maximum of 256 colors, and the bmiColors member of BITMAPINFO contains up to 256 entries. In this case, each byte in the array
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/// represents a single pixel.
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/// </description>
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/// </item>
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/// <item>
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/// <term>16</term>
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/// <description>
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/// The bitmap has a maximum of 2^16 colors. If the biCompression member of the BITMAPINFOHEADER is BI_RGB, the bmiColors member of BITMAPINFO is
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/// NULL. Each WORD in the bitmap array represents a single pixel. The relative intensities of red, green, and blue are represented with five bits
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/// for each color component. The value for blue is in the least significant five bits, followed by five bits each for green and red. The most
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/// significant bit is not used. The bmiColors color table is used for optimizing colors used on palette-based devices, and must contain the number
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/// of entries specified by the biClrUsed member of the BITMAPINFOHEADER.
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/// <para>
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/// If the biCompression member of the BITMAPINFOHEADER is BI_BITFIELDS, the bmiColors member contains three DWORD color masks that specify the red,
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/// green, and blue components, respectively, of each pixel. Each WORD in the bitmap array represents a single pixel.
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/// </para>
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/// <para>
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/// When the biCompression member is BI_BITFIELDS, bits set in each DWORD mask must be contiguous and should not overlap the bits of another mask.
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/// All the bits in the pixel do not have to be used.
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/// </para>
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/// </description>
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/// </item>
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/// <item>
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/// <term>24</term>
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/// <description>
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/// The bitmap has a maximum of 2^24 colors, and the bmiColors member of BITMAPINFO is NULL. Each 3-byte triplet in the bitmap array represents the
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/// relative intensities of blue, green, and red, respectively, for a pixel. The bmiColors color table is used for optimizing colors used on
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/// palette-based devices, and must contain the number of entries specified by the biClrUsed member of the BITMAPINFOHEADER.
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/// </description>
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/// </item>
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/// <item>
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/// <term>32</term>
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/// <description>
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/// The bitmap has a maximum of 2^32 colors. If the biCompression member of the BITMAPINFOHEADER is BI_RGB, the bmiColors member of BITMAPINFO is
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/// NULL. Each DWORD in the bitmap array represents the relative intensities of blue, green, and red for a pixel. The value for blue is in the least
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/// significant 8 bits, followed by 8 bits each for green and red. The high byte in each DWORD is not used. The bmiColors color table is used for
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/// optimizing colors used on palette-based devices, and must contain the number of entries specified by the biClrUsed member of the BITMAPINFOHEADER.
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/// <para>
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/// If the biCompression member of the BITMAPINFOHEADER is BI_BITFIELDS, the bmiColors member contains three DWORD color masks that specify the red,
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/// green, and blue components, respectively, of each pixel. Each DWORD in the bitmap array represents a single pixel.
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/// </para>
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/// <para>
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/// When the biCompression member is BI_BITFIELDS, bits set in each DWORD mask must be contiguous and should not overlap the bits of another mask.
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/// All the bits in the pixel do not need to be used.
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/// </para>
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/// </description>
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/// </item>
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/// </list>
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/// </summary>
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public ushort biBitCount;
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/// <summary>The type of compression for a compressed bottom-up bitmap (top-down DIBs cannot be compressed).</summary>
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public BitmapCompressionMode biCompression;
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/// <summary>
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/// The size, in bytes, of the image. This may be set to zero for BI_RGB bitmaps. If biCompression is BI_JPEG or BI_PNG, biSizeImage indicates the
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/// size of the JPEG or PNG image buffer, respectively.
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/// </summary>
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public uint biSizeImage;
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/// <summary>
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/// The horizontal resolution, in pixels-per-meter, of the target device for the bitmap. An application can use this value to select a bitmap from a
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/// resource group that best matches the characteristics of the current device.
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/// </summary>
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public int biXPelsPerMeter;
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/// <summary>The vertical resolution, in pixels-per-meter, of the target device for the bitmap.</summary>
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public int biYPelsPerMeter;
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/// <summary>
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/// The number of color indexes in the color table that are actually used by the bitmap. If this value is zero, the bitmap uses the maximum number of
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/// colors corresponding to the value of the biBitCount member for the compression mode specified by biCompression.
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/// <para>
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/// If biClrUsed is nonzero and the biBitCount member is less than 16, the biClrUsed member specifies the actual number of colors the graphics engine
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/// or device driver accesses. If biBitCount is 16 or greater, the biClrUsed member specifies the size of the color table used to optimize
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/// performance of the system color palettes. If biBitCount equals 16 or 32, the optimal color palette starts immediately following the three DWORD masks.
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/// </para>
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/// <para>
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/// When the bitmap array immediately follows the BITMAPINFO structure, it is a packed bitmap. Packed bitmaps are referenced by a single pointer.
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/// Packed bitmaps require that the biClrUsed member must be either zero or the actual size of the color table.
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/// </para>
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/// </summary>
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public uint biClrUsed;
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/// <summary>The number of color indexes that are required for displaying the bitmap. If this value is zero, all colors are required.</summary>
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public uint biClrImportant;
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}
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/// <summary>The RGBQUAD structure describes a color consisting of relative intensities of red, green, and blue.</summary>
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[StructLayout(LayoutKind.Sequential)]
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public struct RGBQUAD
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{
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/// <summary>The intensity of blue in the color.</summary>
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public byte rgbBlue;
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/// <summary>The intensity of green in the color.</summary>
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public byte rgbGreen;
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/// <summary>The intensity of red in the color.</summary>
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public byte rgbRed;
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/// <summary>This member is reserved and must be zero.</summary>
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public byte rgbReserved;
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/// <summary>Gets or sets the color associated with the <see cref="RGBQUAD"/> structure.</summary>
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/// <value>The color.</value>
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public System.Drawing.Color Color
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{
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get { return System.Drawing.Color.FromArgb(rgbReserved, rgbRed, rgbGreen, rgbBlue); }
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set { rgbReserved = value.A; rgbBlue = value.B; rgbGreen = value.G; rgbRed = value.R; }
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}
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}
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public enum DIBColorMode : int
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{
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/// <summary>The BITMAPINFO structure contains an array of literal RGB values.</summary>
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DIB_RGB_COLORS = 0,
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/// <summary>
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/// The bmiColors member of the BITMAPINFO structure is an array of 16-bit indexes into the logical palette of the device context specified by hdc.
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/// </summary>
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DIB_PAL_COLORS = 1
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}
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/// <summary>
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/// The CreateDIBSection function creates a DIB that applications can write to directly. The function gives you a pointer to the location of the bitmap
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/// bit values. You can supply a handle to a file-mapping object that the function will use to create the bitmap, or you can let the system allocate the
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/// memory for the bitmap.
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/// </summary>
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/// <param name="hdc">
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/// A handle to a device context. If the value of iUsage is DIB_PAL_COLORS, the function uses this device context's logical palette to initialize the DIB colors.
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/// </param>
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/// <param name="pbmi">A pointer to a BITMAPINFO structure that specifies various attributes of the DIB, including the bitmap dimensions and colors.</param>
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/// <param name="iUsage">
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/// The type of data contained in the bmiColors array member of the BITMAPINFO structure pointed to by pbmi (either logical palette indexes or literal
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/// RGB values).
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/// </param>
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/// <param name="ppvBits">A pointer to a variable that receives a pointer to the location of the DIB bit values.</param>
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/// <param name="hSection">
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/// A handle to a file-mapping object that the function will use to create the DIB. This parameter can be NULL.
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/// <para>
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/// If hSection is not NULL, it must be a handle to a file-mapping object created by calling the CreateFileMapping function with the PAGE_READWRITE or
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/// PAGE_WRITECOPY flag. Read-only DIB sections are not supported. Handles created by other means will cause CreateDIBSection to fail.
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/// </para>
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/// <para>
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/// If hSection is not NULL, the CreateDIBSection function locates the bitmap bit values at offset dwOffset in the file-mapping object referred to by
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/// hSection. An application can later retrieve the hSection handle by calling the GetObject function with the HBITMAP returned by CreateDIBSection.
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/// </para>
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/// <para>
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/// If hSection is NULL, the system allocates memory for the DIB. In this case, the CreateDIBSection function ignores the dwOffset parameter. An
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/// application cannot later obtain a handle to this memory. The dshSection member of the DIBSECTION structure filled in by calling the GetObject
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/// function will be NULL.
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/// </para>
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/// </param>
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/// <param name="dwOffset">
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/// The offset from the beginning of the file-mapping object referenced by hSection where storage for the bitmap bit values is to begin. This value is
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/// ignored if hSection is NULL. The bitmap bit values are aligned on doubleword boundaries, so dwOffset must be a multiple of the size of a DWORD.
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/// </param>
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/// <returns>
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/// If the function succeeds, the return value is a handle to the newly created DIB, and *ppvBits points to the bitmap bit values.
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/// <para>If the function fails, the return value is NULL, and *ppvBits is NULL.</para>
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/// </returns>
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/// <remarks>
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/// As noted above, if hSection is NULL, the system allocates memory for the DIB. The system closes the handle to that memory when you later delete the
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/// DIB by calling the DeleteObject function. If hSection is not NULL, you must close the hSection memory handle yourself after calling DeleteObject to
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/// delete the bitmap.
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/// <para>You cannot paste a DIB section from one application into another application.</para>
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/// <para>
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/// CreateDIBSection does not use the BITMAPINFOHEADER parameters biXPelsPerMeter or biYPelsPerMeter and will not provide resolution information in the
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/// BITMAPINFO structure.
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/// </para>
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/// <para>
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/// You need to guarantee that the GDI subsystem has completed any drawing to a bitmap created by CreateDIBSection before you draw to the bitmap
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/// yourself. Access to the bitmap must be synchronized. Do this by calling the GdiFlush function. This applies to any use of the pointer to the bitmap
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/// bit values, including passing the pointer in calls to functions such as SetDIBits.
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/// </para>
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/// <para>ICM: No color management is done.</para>
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/// </remarks>
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[DllImport(GDI32, ExactSpelling = true, SetLastError = true)]
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public static extern IntPtr CreateDIBSection(SafeDCHandle hdc, ref BITMAPINFO pbmi, DIBColorMode iUsage, out IntPtr ppvBits, IntPtr hSection, int dwOffset);
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/// <summary>
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/// The GetDIBits function retrieves the bits of the specified compatible bitmap and copies them into a buffer as a DIB using the specified format.
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/// </summary>
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/// <param name="hdc">A handle to the device context.</param>
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/// <param name="hbmp">A handle to the bitmap. This must be a compatible bitmap (DDB).</param>
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/// <param name="uStartScan">The first scan line to retrieve.</param>
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/// <param name="cScanLines">The number of scan lines to retrieve.</param>
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/// <param name="lpvBits">
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/// A pointer to a buffer to receive the bitmap data. If this parameter is NULL, the function passes the dimensions and format of the bitmap to the
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/// BITMAPINFO structure pointed to by the lpbi parameter.
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/// </param>
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/// <param name="lpbi">A pointer to a BITMAPINFO structure that specifies the desired format for the DIB data.</param>
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/// <param name="uUsage">The format of the bmiColors member of the BITMAPINFO structure.</param>
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/// <returns>
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/// If the lpvBits parameter is non-NULL and the function succeeds, the return value is the number of scan lines copied from the bitmap.
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/// <para>If the lpvBits parameter is NULL and GetDIBits successfully fills the BITMAPINFO structure, the return value is nonzero.</para>
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/// <para>If the function fails, the return value is zero.</para>
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/// </returns>
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/// <remarks>
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/// If the requested format for the DIB matches its internal format, the RGB values for the bitmap are copied. If the requested format doesn't match the
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/// internal format, a color table is synthesized. The following table describes the color table synthesized for each format.
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/// <list type="table">
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/// <listheader><term>Value</term><description>Meaning</description></listheader>
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/// <item><term>1_BPP</term><description>The color table consists of a black and a white entry.</description></item>
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/// <item><term>4_BPP</term><description>The color table consists of a mix of colors identical to the standard VGA palette.</description></item>
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/// <item><term>8_BPP</term><description>The color table consists of a general mix of 256 colors defined by GDI. (Included in these 256 colors are the 20 colors found in the default logical palette.)</description></item>
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/// <item><term>24_BPP</term><description>No color table is returned.</description></item>
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/// </list>
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/// <para>
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/// If the lpvBits parameter is a valid pointer, the first six members of the BITMAPINFOHEADER structure must be initialized to specify the size and
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/// format of the DIB. The scan lines must be aligned on a DWORD except for RLE compressed bitmaps.
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/// </para>
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/// <para>
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/// A bottom-up DIB is specified by setting the height to a positive number, while a top-down DIB is specified by setting the height to a negative
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/// number. The bitmap color table will be appended to the BITMAPINFO structure.
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/// </para>
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/// <para>
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/// If lpvBits is NULL, GetDIBits examines the first member of the first structure pointed to by lpbi. This member must specify the size, in bytes, of a
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/// BITMAPCOREHEADER or a BITMAPINFOHEADER structure. The function uses the specified size to determine how the remaining members should be initialized.
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/// </para>
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/// <para>
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/// If lpvBits is NULL and the bit count member of BITMAPINFO is initialized to zero, GetDIBits fills in a BITMAPINFOHEADER structure or BITMAPCOREHEADER
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/// without the color table. This technique can be used to query bitmap attributes.
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/// </para>
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/// <para>The bitmap identified by the hbmp parameter must not be selected into a device context when the application calls this function.</para>
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/// <para>The origin for a bottom-up DIB is the lower-left corner of the bitmap; the origin for a top-down DIB is the upper-left corner.</para>
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/// </remarks>
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[DllImport(GDI32, ExactSpelling = true, SetLastError = true)]
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public static extern int GetDIBits(SafeDCHandle hdc, IntPtr hbmp, int uStartScan, int cScanLines, ref byte[] lpvBits, ref BITMAPINFO lpbi, DIBColorMode uUsage);
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/// <summary>
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/// The GetDIBits function retrieves the bits of the specified compatible bitmap and copies them into a buffer as a DIB using the specified format.
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/// </summary>
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/// <param name="hdc">A handle to the device context.</param>
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/// <param name="hbmp">A handle to the bitmap. This must be a compatible bitmap (DDB).</param>
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/// <param name="uStartScan">The first scan line to retrieve.</param>
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/// <param name="cScanLines">The number of scan lines to retrieve.</param>
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/// <param name="lpvBits">
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/// A pointer to a buffer to receive the bitmap data. If this parameter is NULL, the function passes the dimensions and format of the bitmap to the
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/// BITMAPINFO structure pointed to by the lpbi parameter.
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/// </param>
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/// <param name="lpbi">A pointer to a BITMAPINFO structure that specifies the desired format for the DIB data.</param>
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/// <param name="uUsage">The format of the bmiColors member of the BITMAPINFO structure.</param>
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/// <returns>
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/// If the lpvBits parameter is non-NULL and the function succeeds, the return value is the number of scan lines copied from the bitmap.
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/// <para>If the lpvBits parameter is NULL and GetDIBits successfully fills the BITMAPINFO structure, the return value is nonzero.</para>
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/// <para>If the function fails, the return value is zero.</para>
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/// </returns>
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/// <remarks>
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/// If the requested format for the DIB matches its internal format, the RGB values for the bitmap are copied. If the requested format doesn't match the
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/// internal format, a color table is synthesized. The following table describes the color table synthesized for each format.
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/// <list type="table">
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/// <listheader><term>Value</term><description>Meaning</description></listheader>
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/// <item><term>1_BPP</term><description>The color table consists of a black and a white entry.</description></item>
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/// <item><term>4_BPP</term><description>The color table consists of a mix of colors identical to the standard VGA palette.</description></item>
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/// <item><term>8_BPP</term><description>The color table consists of a general mix of 256 colors defined by GDI. (Included in these 256 colors are the 20 colors found in the default logical palette.)</description></item>
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/// <item><term>24_BPP</term><description>No color table is returned.</description></item>
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/// </list>
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/// <para>
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/// If the lpvBits parameter is a valid pointer, the first six members of the BITMAPINFOHEADER structure must be initialized to specify the size and
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/// format of the DIB. The scan lines must be aligned on a DWORD except for RLE compressed bitmaps.
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/// </para>
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/// <para>
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/// A bottom-up DIB is specified by setting the height to a positive number, while a top-down DIB is specified by setting the height to a negative
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/// number. The bitmap color table will be appended to the BITMAPINFO structure.
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/// </para>
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/// <para>
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/// If lpvBits is NULL, GetDIBits examines the first member of the first structure pointed to by lpbi. This member must specify the size, in bytes, of a
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/// BITMAPCOREHEADER or a BITMAPINFOHEADER structure. The function uses the specified size to determine how the remaining members should be initialized.
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/// </para>
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/// <para>
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/// If lpvBits is NULL and the bit count member of BITMAPINFO is initialized to zero, GetDIBits fills in a BITMAPINFOHEADER structure or BITMAPCOREHEADER
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/// without the color table. This technique can be used to query bitmap attributes.
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/// </para>
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/// <para>The bitmap identified by the hbmp parameter must not be selected into a device context when the application calls this function.</para>
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/// <para>The origin for a bottom-up DIB is the lower-left corner of the bitmap; the origin for a top-down DIB is the upper-left corner.</para>
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/// </remarks>
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[DllImport(GDI32, ExactSpelling = true, SetLastError = true)]
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public static extern int GetDIBits(SafeDCHandle hdc, IntPtr hbmp, int uStartScan, int cScanLines, IntPtr lpvBits, ref BITMAPINFO lpbi, DIBColorMode uUsage);
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}
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} |