comp.lang.idl-pvwave archive: archive » Re: Coyote Color Program Updates

Home » Public Forums » archive » Re: Coyote Color Program Updates

Show: Today's Messages :: Show Polls :: Message Navigator
E-mail to friend

Re: Coyote Color Program Updates [message #60365 is a reply to message #60364]

Fri, 16 May 2008 09:39

fburton
Messages: 19
Registered: June 2003

Junior Member

In article <47326671-81ab-4ce1-b5d2-70dd853d8527@f36g2000hsa.googlegroups.com>,
Vince Hradil <hradilv@yahoo.com> wrote:
> On May 16, 10:42 am, Jeremy Bailin <astroco...@gmail.com> wrote:
>> On the subject of useful colour tables, does anyone have a good
>> "velocity map" colour table? Something that goes from red through
>> green to blue, kind of like PRISM, but that becomes significantly non-
>> green closer to 128 that goes to strong-red and strong-blue at the
>> ends rather than at intermediate indices?
>>
>> -Jeremy.
>
> Well... making your own is not that difficult.
> http://www.dfanning.com/color_tips/create_colortable.html

My programs allow users to specify colour scales by giving a series
of letters (and 0 for black, 1 for white). Each letter represents a
particular colour, with R being primary red (255,0,0), G being green,
B blue etc. Interpolation is in RGB space. So a 'standard' red-thru-
green-thru-blue' would be represented by the string "RGB". Greyscale
would be "01". More subtle scales can be constructed by adding extra
letters. You could get a more 'pinched' scale by specifying "RRGBB",
though this would produce regions at the end in which the colour
didn't change. Alternatively, you could use special characters that
extend the 'influence' of the adjacent colour letter, e.g. "R>G<B".

The advantage of this method is that it is intuitive and users can
play about with letters to get immediate feedback. I have used it to
reproduce most standard 'special purpose' colour scales in published
papers and in IDL and Matlab.

Unfortunately, it's in Delphi (but could be converted to IDL easily
enough, I imagine).

Francis

Report message to a moderator

[Message index]

		Re: Coyote Color Program Updates By: David Fanning on Sun, 18 May 2008 16:05
		Re: Coyote Color Program Updates By: ph le sager on Sat, 17 May 2008 12:12
		Re: Coyote Color Program Updates By: Jeremy Bailin on Sat, 17 May 2008 06:02
		Re: Coyote Color Program Updates By: wlandsman on Fri, 16 May 2008 09:45
		Re: Coyote Color Program Updates By: fburton on Fri, 16 May 2008 09:39
		Re: Coyote Color Program Updates By: Vince Hradil on Fri, 16 May 2008 08:51
		Re: Coyote Color Program Updates By: Jeremy Bailin on Fri, 16 May 2008 08:42

Previous Topic:	borders of segments
Next Topic:	Generalized Least Squares?

-=] Back to Top [=-

[ Syndicate this forum (XML) ] [

] [

]

Current Time: Fri Oct 10 20:04:19 PDT 2025

Total time taken to generate the page: 0.71759 seconds