Created CopyRectangle (markdown)

CopyRectangle.md

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+Copies a rectangle of pixels from one image to another.
+
+_Block compressed images are not supported as either the source or destination. Use [Decompress] to uncompress BC images before using this function._
+
+    HRESULT CopyRectangle( const Image& srcImage, const Rect& srcRect,
+       const Image& dstImage,
+       DWORD filter, size_t xOffset, size_t yOffset );
+
+# Parameters
+
+_srcRect_: A rectangle described with _x_, _y_ of the upper right corner, and _w_ and _h_ with the width and height, which indicates pixel location from _srcImage_ to copy. The _w_ and _h_ also define the size of the destination rectangle in _dstImage_. Both rectangles must be valid for the size of the images (i.e. the API does not support clipping).
+
+_filter_: See [[Filter Flags]]. Source and destination images do not need to be the same format, in which case conversions will use these flags.
+
+_xOffset_, _yOffset_: Pixel location of destination rectangle in _dstImage_. The width and height of the destination rectangle is the same as _srcRect.w_ and _srcRect.h_.
+
+# Example
+
+Here's an example that copies a source image to the location (100,50) location in a new, larger image.
+
+    ScratchImage srcImage;
+
+    ...
+
+    ScratchImage destImage;
+    destImage.Iniitalize2D( ... );
+
+    auto mdata = srcImage.GetMetadata();
+    Rect r( 0, 0, mdata.width, mdata.height );
+    hr = CopyRectangle( *srcImage.GetImage(0,0,0), r, *dstImage.GetImage(0,0,0), 
+       TEX_FILTER_DEFAULT, 100, 50 );
+    if ( FAILED(hr) )
+        ...
+
+# Remarks
+
+Behavior of this function is not defined if the source and destination image are the same and the source and destination rectangles overlap.