BOOL StretchBlt( int x, int y, int nWidth, int nHeight, CDC* pSrcDC, int xSrc, int ySrc, int nSrcWidth, int nSrcHeight, DWORD dwRop ); 在nWidth和nHeight处乘上缩放比例,它们确定了目标区矩形的宽度和高度,所以可以通过它们实现缩放。 其中所有参数意义如下: x Specifies the x-coordinate (in logical units) of the upper-left corner ofthedestination rectangle. y Specifies the y-coordinate (in logical units) of the upper-left corner of the destination rectangle. nWidth Specifies the width (in logical units) of the destination rectangle. nHeight Specifies the height (in logical units) of the destination rectangle. pSrcDC Specifies the source device context. xSrc Specifies the x-coordinate (in logical units) of the upper-left corner of the source rectangle. ySrc Specifies the x-coordinate (in logical units) of the upper-left corner of the source rectangle. nSrcWidth Specifies the width (in logical units) of the source rectangle. nSrcHeight Specifies the height (in logical units) of the source rectangle. dwRop Specifies the raster operation to be performed. Raster operation codes define how GDI combines colors in output operations that involve a current brush, a possible source bitmap, and a destination bitmap. This parameter may be one of the following values:
在nWidth和nHeight处乘上缩放比例,它们确定了目标区矩形的宽度和高度,所以可以通过它们实现缩放。
其中所有参数意义如下:
x Specifies the x-coordinate (in logical units) of the upper-left corner ofthedestination rectangle.
y Specifies the y-coordinate (in logical units) of the upper-left corner of the destination rectangle.
nWidth Specifies the width (in logical units) of the destination rectangle.
nHeight Specifies the height (in logical units) of the destination rectangle.
pSrcDC Specifies the source device context.
xSrc Specifies the x-coordinate (in logical units) of the upper-left corner of the source rectangle.
ySrc Specifies the x-coordinate (in logical units) of the upper-left corner of the source rectangle.
nSrcWidth Specifies the width (in logical units) of the source rectangle.
nSrcHeight Specifies the height (in logical units) of the source rectangle.
dwRop Specifies the raster operation to be performed. Raster operation codes define how GDI combines colors in output operations that involve a current brush, a possible source bitmap, and a destination bitmap. This parameter may be one of the following values: