The verticaltextrotationangle doesn't work when use with a floating box using a negative zindex..
Rotation attribute is set in the code behind like that (for both floating box).
(pdf.Sections[0].GetObjectByID("fbDivision") as FloatingBox).VerticalTextRotationAngle = VerticalTextRotationType.AntiClockWise;
See the xml exemple bellow with the ouput (in attachement)
I am using version 5.0.0.0 of aspose.pdf (with total license)..
<?xml version="1.0" encoding="utf-8" ?>
<Pdf xmlns="Aspose.Pdf" DestinationType="FitPage" IsLandscape="false" Author="test" BackgroundColor="White">
<Section ID="FrontPage" PageWidth="8.5inch" PageHeight="11inch" >
<FloatingBox id="fbDivision" Left="1inch" Top="1inch" width="5inch" height="0.75inch" zIndex="-10">
<text >
<Segment >Test with negative zIndex
</Segment>
</text>
</FloatingBox>
<FloatingBox id="fbTitle" Left="1inch" Top="2inch" width="5inch" height="0.75inch" zIndex="10" >
<text >
<Segment >Test whitout zIndex
</Segment>
</text>
</FloatingBox>
</Section>
</Pdf>