SCOTT OFRIEL (ofriels1++at++qmsmtpgw.mugu.navy.mil)
22 Jan 1997 08:35:12 U
What I am doing is a 3D type bar graph where each bar represents a radar's
range and/or doppler gate (range (x-axis) vs. doppler (y-axis)). The height
of the gate (z-axis) represents the amplitude of the signal in that particular
gate. I would like to have the amplitude of each gate related to color where
blue is the lowest energy and red is the highest. The line I was referring
to is the z-axis which is the amplitude axis and is Gouraud shaded from blue
to red.
For example, if a the max signal strength was 80db and a gates value was 80 db
that bar would be Gouraud shaded from blue to red. If the signal strength for
a gate was 40db the bar would have the same color as the z-axis, from blue to
the color of at the mid-point of the z-axis.
Thanks again,
Scott O'Friel
------------------------------
Date: 1/21/97 7:33 PM
To: OFRIEL, SCOTT
From: Angus Dorbie
This is a linear interpolation in screen space.
Problems will arise if you want to calculate this for projected
screen space and the line is in perspective because the colour
interpolation is not perspective correct. This gets real fun
when you clip the line because the colour gets shaded from the
interpolated clipped line end colour.
Could you give a little more info on why you want to do this so
I can better understand how these issues might relate to you?
Cheers,
Angus.
On Jan 21, 5:58pm, SCOTT OFRIEL wrote:
> Subject: Getting Gouraud Color
> Subject: Time: 5:42 PM
> OFFICE MEMO Getting Gouraud Color Date: 1/21/97
>
> Performer:
>
> Is it possible to get the RGB color value from any place between the two end
> points of a Gouraud shaded line? The line is a pfGeoSet.
>
> Thank you,
> Scott O'Friel
>
>
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>-- End of excerpt from SCOTT OFRIEL
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Date: Wed, 22 Jan 1997 02:54:56 +0000
In-Reply-To: "SCOTT OFRIEL" <ofriels1++at++qmsmtpgw.mugu.navy.mil>
"Getting Gouraud Color" (Jan 21, 5:58pm)
References: <n1358253152.63742++at++qmsmtpgw.mugu.navy.mil>
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