[vtkusers] Giving lines a gradient opacity

[Lisa Sobierajski Avila]

Hello Eric,

You need to associate scalars with the points in your lines. You would then 
use a lookup table to define the RGBA color for each scalar value - and 
therefore you can have independent color/opacity at each end of the line. 
How well this works for you will depend on your hardware / video driver as 
some of them do a poor job of color interpolation on lines.

Lisa


At 05:56 AM 8/19/2001, Eric Charles Woods wrote:
>I am wanting to display vector data as simple lines with 2 points,
>and I am currently using vtkLineSource ok.
>
>Problem is, I would like to indicate the directions of the lines by
>having it fade from fully opaque to fully transparent.  To do this I
>would like to be able to give each endpoint a different opacity value.
>Is this possible?
>
>Even giving each endpoint a different colour value could be better
>than a kick in the pants.
>
>Can anyone think of anything other than a kick in the pants?
>
>thanks
>
>
>-=^=^=^=^=^=^=^=^=^=^=^=^=^=^=^=^=^=^=-
>Eric Woods
>Applied Management & Computing Division
>Lincoln University
>Ph   3253838 ext 8813
>Cell 025 605 6021
>-=^=^=^=^=^=^=^=^=^=^=^=^=^=^=^=^=^=^=-
>
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