Class Gdi32Api

Gdi32 Helpers

Inheritance

System.Object

Gdi32Api

Namespace: Dapplo.Windows.Gdi32

Assembly: Dapplo.Windows.Gdi32.dll

Syntax

public static class Gdi32Api : object

Methods

BitBlt(Graphics, Bitmap, Rectangle, Point, RasterOperations)

Bitblt extension for the graphics object

Declaration

public static void BitBlt(this Graphics target, Bitmap sourceBitmap, Rectangle source, Point destination, RasterOperations rasterOperations)

Parameters

Type	Name	Description
Graphics	target	Graphics
Bitmap	sourceBitmap	Bitmap
Rectangle	source	Rectangle
Point	destination	Point
RasterOperations	rasterOperations	RasterOperations

BitBlt(SafeHandle, Int32, Int32, Int32, Int32, SafeHandle, Int32, Int32, RasterOperations)

The BitBlt function performs a bit-block transfer of the color data corresponding to a rectangle of pixels from the specified source device context into a destination device context.

Declaration

public static bool BitBlt(SafeHandle hdcDest, int nXDest, int nYDest, int nWidth, int nHeight, SafeHandle hdcSrc, int nXSrc, int nYSrc, RasterOperations rasterOperation)

Parameters

Type	Name	Description
SafeHandle	hdcDest	A handle to the destination device context.
System.Int32	nXDest	The x-coordinate, in logical units, of the upper-left corner of the destination rectangle.
System.Int32	nYDest	The y-coordinate, in logical units, of the upper-left corner of the destination rectangle.
System.Int32	nWidth	The width, in logical units, of the source and destination rectangles.
System.Int32	nHeight	The height, in logical units, of the source and the destination rectangles.
SafeHandle	hdcSrc	A handle to the source device context.
System.Int32	nXSrc	The x-coordinate, in logical units, of the upper-left corner of the source rectangle.
System.Int32	nYSrc	The y-coordinate, in logical units, of the upper-left corner of the source rectangle.
RasterOperations	rasterOperation	A raster-operation code. These codes define how the color data for the source rectangle is to be combined with the color data for the destination rectangle to achieve the final color.

Returns

Type	Description
System.Boolean

CreateCompatibleDC(SafeHandle)

The CreateCompatibleDC function creates a memory device context (DC) compatible with the specified device. See CreateCompatibleDC function

Declaration

public static SafeCompatibleDcHandle CreateCompatibleDC(SafeHandle hDc)

Parameters

Type	Name	Description
SafeHandle	hDc	A handle to an existing DC. If this handle is NULL, the function creates a memory DC compatible with the application's current screen.

Returns

Type	Description
SafeCompatibleDcHandle	If the function succeeds, the return value is the handle to a memory DC. If the function fails, the return value is NULL.

CreateDIBSection(SafeHandle, ref BitmapInfoHeader, UInt32, out IntPtr, IntPtr, UInt32)

The CreateDIBSection function creates a DIB that applications can write to directly. The function gives you a pointer to the location of the bitmap 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 memory for the bitmap. See CreateDIBSection function

Declaration

public static SafeDibSectionHandle CreateDIBSection(SafeHandle hdc, ref BitmapInfoHeader bmi, uint usage, out IntPtr bits, IntPtr hSection, uint dwOffset)

Parameters

Type	Name	Description
SafeHandle	hdc	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.
BitmapInfoHeader	bmi	A pointer to a BITMAPINFO structure that specifies various attributes of the DIB, including the bitmap dimensions and colors.
System.UInt32	usage	The type of data contained in the bmiColors array member of the BITMAPINFO structure pointed to by pbmi (either logical palette indexes or literal RGB values). The following values are defined. DIB_PAL_COLORS The bmiColors member is an array of 16-bit indexes into the logical palette of the device context specified by hdc. DIB_RGB_COLORS The BITMAPINFO structure contains an array of literal RGB values.
IntPtr	bits	A pointer to a variable that receives a pointer to the location of the DIB bit values.
IntPtr	hSection	A handle to a file-mapping object that the function will use to create the DIB. This parameter can be NULL. 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 PAGE_WRITECOPY flag. Read-only DIB sections are not supported. Handles created by other means will cause CreateDIBSection to fail. If hSection is not NULL, the CreateDIBSection function locates the bitmap bit values at offset dwOffset in the file-mapping object referred to by hSection. An application can later retrieve the hSection handle by calling the GetObject function with the HBITMAP returned by CreateDIBSection. If hSection is NULL, the system allocates memory for the DIB. In this case, the CreateDIBSection function ignores the dwOffset parameter. An application cannot later obtain a handle to this memory. The dshSection member of the DIBSECTION structure filled in by calling the GetObject function will be NULL.
System.UInt32	dwOffset	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 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.

Returns

Type	Description
SafeDibSectionHandle	If the function succeeds, the return value is a handle to the newly created DIB, and *ppvBits points to the bitmap bit values. If the function fails, the return value is NULL, and *ppvBits is NULL.

CreateRectRgn(Int32, Int32, Int32, Int32)

The CreateRectRgn function creates a rectangular region. See CreateRectRgn function

Declaration

public static SafeRegionHandle CreateRectRgn(int nLeftRect, int nTopRect, int nRightRect, int nBottomRect)

Parameters

Type	Name	Description
System.Int32	nLeftRect	Specifies the x-coordinate of the upper-left corner of the region in logical units.
System.Int32	nTopRect	Specifies the y-coordinate of the upper-left corner of the region in logical units.
System.Int32	nRightRect	Specifies the x-coordinate of the lower-right corner of the region in logical units.
System.Int32	nBottomRect	Specifies the y-coordinate of the lower-right corner of the region in logical units.

Returns

Type	Description
SafeRegionHandle	If the function succeeds, the return value is the handle to the region. If the function fails, the return value is NULL.

GetDeviceCaps(SafeHandle, DeviceCaps)

See GetDeviceCaps function The GetDeviceCaps function retrieves device-specific information for the specified device.

Declaration

public static int GetDeviceCaps(SafeHandle hdc, DeviceCaps nIndex)

Parameters

Type	Name	Description
SafeHandle	hdc	A handle to the DC.
DeviceCaps	nIndex	The item to be returned

Returns

Type	Description
System.Int32

GetPixel(SafeHandle, Int32, Int32)

See GetPixel function The GetPixel function retrieves the red, green, blue (RGB) color value of the pixel at the specified coordinates.

Declaration

public static uint GetPixel(SafeHandle hdc, int nXPos, int nYPos)

Parameters

Type	Name	Description
SafeHandle	hdc	A handle to the device context.
System.Int32	nXPos	The x-coordinate, in logical units, of the pixel to be examined.
System.Int32	nYPos	The y-coordinate, in logical units, of the pixel to be examined.

Returns

Type	Description
System.UInt32	The return value is the COLORREF value that specifies the RGB of the pixel. If the pixel is outside of the current clipping region, the return value is CLR_INVALID (0xFFFFFFFF defined in Wingdi.h).

SelectObject(SafeHandle, SafeHandle)

The SelectObject function selects an object into the specified device context (DC). The new object replaces the previous object of the same type.

Declaration

public static IntPtr SelectObject(SafeHandle hDc, SafeHandle hObject)

Parameters

Type	Name	Description
SafeHandle	hDc	A handle to the DC.
SafeHandle	hObject	A handle to the object to be selected. The specified object must have been created by using one of the following functions. Object Functions Bitmap CreateBitmap, CreateBitmapIndirect, CreateCompatibleBitmap, CreateDIBitmap, CreateDIBSection (Bitmaps can only be selected into memory DC's. A single bitmap cannot be selected into more than one DC at the same time.) Brush CreateBrushIndirect, CreateDIBPatternBrush, CreateDIBPatternBrushPt, CreateHatchBrush, CreatePatternBrush, CreateSolidBrush Font CreateFont, CreateFontIndirect Pen CreatePen, CreatePenIndirect Region CombineRgn, CreateEllipticRgn, CreateEllipticRgnIndirect, CreatePolygonRgn, CreateRectRgn, CreateRectRgnIndirect

Returns

Type	Description
IntPtr	If the selected object is not a region and the function succeeds, the return value is a handle to the object being replaced. If the selected object is a region and the function succeeds, the return value is one of the following values. SIMPLEREGION Region consists of a single rectangle. COMPLEXREGION Region consists of more than one rectangle. NULLREGION Region is empty.

StretchBlt(Graphics, Bitmap, Rectangle, Rectangle, RasterOperations)

StretchBlt extension for the graphics object Doesn't work?

Declaration

public static void StretchBlt(this Graphics target, Bitmap sourceBitmap, Rectangle source, Rectangle destination, RasterOperations rasterOperation)

Parameters

Type	Name	Description
Graphics	target	Graphics
Bitmap	sourceBitmap	Bitmap
Rectangle	source	Rectangle
Rectangle	destination	Rectangle
RasterOperations	rasterOperation	RasterOperations