Problem:

When linework is drawn first and text (background on, higher display priority, & transparency) is drawn over it, the text becomes obscured by the linework, making it difficult to read.

However, if the order of element placement is reversed, with the text placed first and the linework then drawn over it (reverse order of normal operations), the text is not obscured and clearly readable.

Reason for Concern:

We (Michigan DOT) currently apply transparency to existing roadway objects so they partially fade into the background, making the proposed new objects more readable, which is very helpful for cluttered design drawings.

We would like to also apply transparency to the text and dimensions associated with the existing objects, but are unable to do so for the reason explained above.

See below for further details and see the attached video for full details.

Example:

Text Style: Arial TTF, Background masking turned on.

Text Level: Display Priority 260, Transparency 50%

Linework Level: Display Priority 0, Transparency 0%

For the above settings, if the text is placed first and linework is then drawn over top of it (reverse order of operations), the text style will successfully mask the linework.

However, if the linework is placed first and then the text is drawn over top of it (normal order of operations), the text becomes obscured by the linework.

The problem involves a combination of the following variables:

• Order of element placement.

• Level Manager Settings: Display Priority & Transparency

• Text Style Background (masking)

This behavior is also observed in MicroStation SS10 and has therefore been ruled by Bentley to be "Working as Designed". We would argue that this is a bug that also exists in SS10.