Graphics::DrawImage Method (Image^, array<PointF>^, RectangleF, GraphicsUnit, ImageAttributes^)

 
System_CAPS_noteNote

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Draws the specified portion of the specified Image at the specified location and with the specified size.

Namespace:   System.Drawing
Assembly:  System.Drawing (in System.Drawing.dll)

public:
void DrawImage(
	Image^ image,
	array<PointF>^ destPoints,
	RectangleF srcRect,
	GraphicsUnit srcUnit,
	ImageAttributes^ imageAttr
)

Parameters

image
Type: System.Drawing::Image^

Image to draw.

destPoints
Type: array<System.Drawing::PointF>^

Array of three PointF structures that define a parallelogram.

srcRect
Type: System.Drawing::RectangleF

RectangleF structure that specifies the portion of the image object to draw.

srcUnit
Type: System.Drawing::GraphicsUnit

Member of the GraphicsUnit enumeration that specifies the units of measure used by the srcRect parameter.

imageAttr
Type: System.Drawing.Imaging::ImageAttributes^

ImageAttributes that specifies recoloring and gamma information for the image object.

Exception Condition
ArgumentNullException

image is null.

The destPoints parameter specifies three points of a parallelogram. The three PointF structures represent the upper-left, upper-right, and lower-left corners of the parallelogram. The fourth point is extrapolated from the first three to form a parallelogram.

The srcRect parameter specifies a rectangular portion of the image object to draw. This portion is scaled and sheared to fit inside the parallelogram specified by the destPoints parameter.

The following code example is designed for use with Windows Forms, and it requires PaintEventArgse, which is a parameter of the Paint event handler. The code performs the following actions:

  • Creates an image from a JPEG file SampImag.jpg in the folder of the example.

  • Creates points that define a destination parallelogram in which to draw the image.

  • Creates a source rectangle from which to extract a portion of the image.

  • Sets the unit of measure of the source rectangle to pixels.

  • Draws the original image to the screen.

  • Creates an additional parallelogram in which to draw an adjusted image.

  • Creates and sets the attributes of the adjusted image to have a larger-than-usual gamma value.

  • Draws the adjusted image to the screen.

For the original, unadjusted destination parallelogram, the position locates the image on the screen, the size of the source rectangle and the size and shape of the destination parallelogram determines the scaling and shearing of the drawn image, and the size of the rectangle determines what portion of the original image is drawn to the screen.

void DrawImageParaFRectFAttrib( PaintEventArgs^ e )
{
   // Create image.
   Image^ newImage = Image::FromFile( "SampImag.jpg" );

   // Create parallelogram for drawing original image.
   PointF ulCorner1 = PointF(100.0F,100.0F);
   PointF urCorner1 = PointF(325.0F,100.0F);
   PointF llCorner1 = PointF(150.0F,250.0F);
   array<PointF>^ destPara1 = {ulCorner1,urCorner1,llCorner1};

   // Create rectangle for source image.
   RectangleF srcRect = RectangleF(50.0F,50.0F,150.0F,150.0F);
   GraphicsUnit units = GraphicsUnit::Pixel;

   // Create parallelogram for drawing adjusted image.
   PointF ulCorner2 = PointF(325.0F,100.0F);
   PointF urCorner2 = PointF(550.0F,100.0F);
   PointF llCorner2 = PointF(375.0F,250.0F);
   array<PointF>^ destPara2 = {ulCorner2,urCorner2,llCorner2};

   // Draw original image to screen.
   e->Graphics->DrawImage( newImage, destPara1, srcRect, units );

   // Create image attributes and set large gamma.
   ImageAttributes^ imageAttr = gcnew ImageAttributes;
   imageAttr->SetGamma( 4.0F );

   // Draw adjusted image to screen.
   e->Graphics->DrawImage( newImage, destPara2, srcRect, units, imageAttr );
}

.NET Framework
Available since 1.1
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