How to draw a transparent line in Direct2D

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I am starting with Direct2D and VC++2013. I am trying to draw a wide line with 50% transparency. On the Microsoft web site I can only find examples of transparency which use the Brush to fill in a transparent color. Can someone show how to draw lines that are transparent in Direct2D. Thanks.

Below should be a link to the Microsoft webpage that dealing with Opacity.

Opacity Masks Overview

Posted 17-Jul-15 12:29pm

Austin_Cpp

Updated 17-Jul-15 17:56pm

Afzaal Ahmad Zeeshan

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PIEBALDconsult 17-Jul-15 19:18pm

How would you know if you didn't?

https://www.youtube.com/watch?v=BKorP55Aqvg

Afzaal Ahmad Zeeshan 17-Jul-15 23:56pm

Just don't, don't draw anything and tell the user it is transparent. :-)

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Patrice T · Answer 1 · 2015-07-18T09:10:00

Why don't you say that your line is a rectangle and simply fill it with your transparent colour ?

[Update]

Quote:
Most lines are DIAGONAL, so cannot be represented by a rectangle. (I didn't bother voting, but if I did, I would also downvote.)

I agree that the answer was short.
But you are making a mistake in your analyze, it looks like you believe that a rectangle is either horizontal or vertical, but you make a mistake.
When you rotate a rectangle, it stay a rectangle, even rotated.

By replacing the line by a rectangle, you make a polygon and the brush tool can be used to fill it.