[GRASSLIST:3232] nice color ramp

GRASS GRASS user
1

This is a nice color ramp. A year or so ago, I remember someone else coming up with a nice elevation color ramp. I did one for elevation maps in the Spearfish demo set that has a somewhat different approach, using percentages for part.

A wish (maybe silly or trivial):
It would be nice if there was someplace people could post color ramps like these, and other such interchangeable files like icons so that others could use them. For example, playing around I made a bug icon for bugsites in the Spearfish data along with house, powerline, and trowel (I'm an archaeologist) icons. I'd be happy to share them and the color ramp.

Michael Barton

On Monday, April 19, 2004, at 10:01 PM, Multiple recipients of list wrote:

From: Hamish <hamish_nospam@yahoo.com>
Date: Mon Apr 19, 2004 7:40:51 PM America/Phoenix
To: Richard Greenwood <rich@greenwoodmap.com>
Cc: grass list <GRASSLIST@baylor.edu>
Subject: [GRASSLIST:3221] Re: colors for d.his

Could anyone provide hints for creating a nice color ramp for the map
used as the hue parameter of d.his suitable for representing an alpine
valley in which the lowest elevations would be green going to brown,
grey, and white for the highest elevations?

see:
http://intevation.de/rt/webrt?serial_num=2072

thus,

r.colors map=xxxx col=rules << EOF
-11000 0 0 0
-500 0 0 30
-100 0 0 200
-1 150 150 255
0 0 150 0
270 90 165 90
300 90 175 90
500 50 180 50
500 70 170 70
1000 70 145 75
1000 70 155 75
2000 150 156 100
2800 220 220 220
3000 255 255 255
8850 255 255 255
nv 255 255 255
EOF

i.e. [elevation Red Green Blue]

or for your suggested colors, use these rules:

0% green
33.3% brown
66.7% grey
100% white

Hamish

______________________________
Michael Barton, Professor & Curator
Department of Anthropology
Arizona State University
Tempe, AZ 85287-2402
USA

voice: 480-965-6262; fax: 480-965-7671
www: http://www.public.asu.edu/~cmbarton

2

I agree, it would be useful to have a library of color ramps and such. For whatever it's worth, here's the color ramp I use for topography of western Turkey. It's tailored for the specific archaeological site I work on (Sardis), but could be modified easily. I wanted to show the topographic change from flatter river valley (in the 100-200 meter range, greenish) to steeper hills above 240 meters or so. I mucked around to make it more generally applicable to western Turkey.

-32768 blue
0 blue
1 0 230 0
160 0 160 0
240 50 130 0
384 120 100 30
480 120 130 40
720 170 160 50
1600 255 255 100

Nick Cahill

On Apr 20, 2004, at 10:42 AM, Michael Barton wrote:

This is a nice color ramp. A year or so ago, I remember someone else coming up with a nice elevation color ramp. I did one for elevation maps in the Spearfish demo set that has a somewhat different approach, using percentages for part.

A wish (maybe silly or trivial):
It would be nice if there was someplace people could post color ramps like these, and other such interchangeable files like icons so that others could use them. For example, playing around I made a bug icon for bugsites in the Spearfish data along with house, powerline, and trowel (I'm an archaeologist) icons. I'd be happy to share them and the color ramp.

Michael Barton

On Monday, April 19, 2004, at 10:01 PM, Multiple recipients of list wrote:

From: Hamish <hamish_nospam@yahoo.com>
Date: Mon Apr 19, 2004 7:40:51 PM America/Phoenix
To: Richard Greenwood <rich@greenwoodmap.com>
Cc: grass list <GRASSLIST@baylor.edu>
Subject: [GRASSLIST:3221] Re: colors for d.his

Could anyone provide hints for creating a nice color ramp for the map
used as the hue parameter of d.his suitable for representing an alpine
valley in which the lowest elevations would be green going to brown,
grey, and white for the highest elevations?

see:
http://intevation.de/rt/webrt?serial_num=2072

thus,

r.colors map=xxxx col=rules << EOF
-11000 0 0 0
-500 0 0 30
-100 0 0 200
-1 150 150 255
0 0 150 0
270 90 165 90
300 90 175 90
500 50 180 50
500 70 170 70
1000 70 145 75
1000 70 155 75
2000 150 156 100
2800 220 220 220
3000 255 255 255
8850 255 255 255
nv 255 255 255
EOF

i.e. [elevation Red Green Blue]

or for your suggested colors, use these rules:

0% green
33.3% brown
66.7% grey
100% white

Hamish

______________________________
Michael Barton, Professor & Curator
Department of Anthropology
Arizona State University
Tempe, AZ 85287-2402
USA

voice: 480-965-6262; fax: 480-965-7671
www: http://www.public.asu.edu/~cmbarton