检查矢量对象在给定dpi和打印大小的打印时是否可见

drawRect = myDevice.GetDrawRect();
for(oneShape in allShapes)
{
    shapeRect = oneShape.GetRect()
    if(! drawRect.Contains(shapeRect))
         oneShape.MarkAsInvisible(); 
    else
         oneShape.Draw();
}

Contains()函数看起来是这样的,假设y值从下到上递增:

bool Rect::Contains(OtherRect)

{
    if(left   <=  OtherRect.right  &&
       right  >=  OtherRect.left   &&
       top    >=  OtherRect.bottom &&
       bottom <=  OtherRect.top)
       return true

    return false;
}

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