图层设置透明度，Engine中输出图片放大后有马赛克，ArcMap中正常。

private void SetOutputQuality(IActiveView docActiveView, long iResampleRatio)

{

/* This function sets the OutputImageQuality for the active view. If the active view is a pagelayout, then

* it must also set the output image quality for each of the maps in the pagelayout.

*/

IGraphicsContainer docGraphicsContainer;

IElement docElement;

IOutputRasterSettings docOutputRasterSettings;

IMapFrame docMapFrame;

IActiveView tmpActiveView;

if (docActiveView is IMap)

{

docOutputRasterSettings = docActiveView.ScreenDisplay.DisplayTransformation

as IOutputRasterSettings;

docOutputRasterSettings.ResampleRatio = (int)iResampleRatio;

}

else if (docActiveView is IPageLayout)

{

//Assign ResampleRatio for PageLayout

docOutputRasterSettings = docActiveView.ScreenDisplay.DisplayTransformation

as IOutputRasterSettings;

docOutputRasterSettings.ResampleRatio = (int)iResampleRatio;

//and assign ResampleRatio to the maps in the PageLayout.

docGraphicsContainer = docActiveView as IGraphicsContainer;

docGraphicsContainer.Reset();

docElement = docGraphicsContainer.Next();

while (docElement != null)

{

if (docElement is IMapFrame)

{

docMapFrame = docElement as IMapFrame;

tmpActiveView = docMapFrame.Map as IActiveView;

docOutputRasterSettings =

tmpActiveView.ScreenDisplay.DisplayTransformation as

IOutputRasterSettings;

docOutputRasterSettings.ResampleRatio = (int)iResampleRatio;

}

docElement = docGraphicsContainer.Next();

}

docMapFrame = null;

docGraphicsContainer = null;

tmpActiveView = null;

}

docOutputRasterSettings = null;

}