Interactive PowerBasic Forum

The following example draws the original source image and then draws a portion of the image in a specified rectangle.

C++


VOID Example_DrawImage5(HDC hdc)

{
   Graphics graphics(hdc);

   // Create an Image object.
   Image image(L"pattern.png");

   // Draw the original source image.
   graphics.DrawImage(&image, 10, 10);

   // Define the portion of the image to draw.
   int srcX = 70;
   int srcY = 20;
   int srcWidth = 100;
   int srcHeight = 100;

   // Create a Rect object that specifies the destination of the image.
   Rect destRect(200, 10, image.GetWidth(), image.GetHeight());

   // Create an ImageAttributes object that specifies a recoloring from red to blue.
   ImageAttributes remapAttributes;
   ColorMap redToBlue;
   redToBlue.oldColor = Color(255, 255, 0, 0);
   redToBlue.newColor = Color(255, 0, 0, 255);
   remapAttributes.SetRemapTable(1, &redToBlue);

   // Draw the resized image.
   graphics.DrawImage(
   &image,
   destRect,
   srcX,
   srcY,
   srcWidth,
   srcHeight,
   UnitPixel,
   &remapAttributes,
   NULL,
   NULL);
}


PowerBASIC


SUB GDIP_GdipDrawImageRectRect (BYVAL hdc AS DWORD)

   LOCAL hStatus AS LONG
   LOCAL pGraphics AS DWORD
   LOCAL pImage AS DWORD
   LOCAL strFileName AS STRING
   LOCAL nWidth AS DWORD
   LOCAL nHeight AS DWORD
   LOCAL srcx AS SINGLE
   LOCAL srcy AS SINGLE
   LOCAL srcwidth AS SINGLE
   LOCAL srcheight AS SINGLE
   LOCAL pRemapAttributes AS DWORD
   LOCAL redToBlue AS GDIP_COLORMAP
   DIM   destPoints(2) AS POINTF

   hStatus = GdipCreateFromHDC(hdc, pGraphics)

   ' // Create the Image object
   strFileName = UCODE$("pattern.png")
   hStatus = GdipLoadImageFromFile(STRPTR(strFileName), pImage)

   ' // Draw the original source image.
   hStatus = GdipDrawImage(pGraphics, pImage, 10, 10)

   ' // Define the portion of the image to draw.
   srcX = 70.0!
   srcY = 20.0!
   srcwidth = 100.0!
   srcheight = 100.0!

   ' // Get the width and height of the image.
   hStatus = GdipGetImageWidth(pImage, nWidth)
   hStatus = GdipGetImageHeight(pImage, nHeight)

   ' // Create an ImageAttributes object that specifies a recoloring from red to blue.
   hStatus = GdipCreateImageAttributes(pRemapAttributes)
   redToBlue.oldColor = GDIP_ARGB(255, 255, 0, 0)
   redToBlue.newColor = GDIP_ARGB(255, 0, 0, 255)
   hStatus = GdipSetImageAttributesRemapTable(pRemapAttributes, %ColorAdjustTypeDefault, %TRUE, 1, redToBlue)

   ' Draw the cropped image
   hStatus = GdipDrawImageRectRect(pGraphics, pImage, 200, 10, nWidth, nHeight, srcx, srcy, _
             srcwidth, srcheight, %UnitPixel, pRemapAttributes, %NULL, %NULL)

   ' // Cleanup
   IF pRemapAttributes THEN GdipDisposeImageAttributes(pRemapAttributes)
   IF pImage THEN GdipDisposeImage(pImage)
   IF pGraphics THEN GdipDeleteGraphics(pGraphics)

END SUB


(http://www.jose.it-berater.org/captures/GdipDrawImageRectRect.png)