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Mukund
06-22-2011, 04:07 AM
Hello Everyone,

Can anyone please let me know how I could render a height map(slope map)?
PIC (http://www.google.co.in/imgres?imgurl=http://freegeographytools.com/wp-content/uploads/2007/05/slopepic.jpg&imgrefurl=http://freegeographytools.com/2007/terrain-slopeaspect-display-and-analysis&usg=__kfOrXbwRd-si0hEw7nW-02dv-g4=&h=518&w=593&sz=172&hl=en&start=12&zoom=1&itbs= 1&tbnid=1XmXl32aMZQP4M:&tbnh=118&tbnw=135&prev=/search%3Fq%3Daspect%2Bmap%26hl%3Den%26safe%3Doff%2 6sa%3DX%26biw%3D1024%26bih%3D601%26tbm%3Disch%26pr md%3Divns&ei=mLgBTtSbNMvhrAfu2oSGAw)

Here is an example. Now, I tried to generate the map using a lot of lines, i.e finding slope and then assign a color to the line based on the slope. But that becomes very slow. Is there any other way I can do this?

Thanks in advance.

ZbuffeR
06-22-2011, 04:37 AM
An easy and efficient way is to render the terrain normally using triangles, textured with 1D texture representing the color scale, the world up coordinate being used as texture coordinate.
Use "GL_NEAREST" sampling if you want to avoid gradients between colors, and keep the "banding" effect.

Mukund
06-22-2011, 04:43 AM
Thanks for the reply Zbuffer. Could you please explain what you meant by this:

>>keep the "banding" effect.

What exactly did you mean by banding?

Thanks.

ZbuffeR
06-22-2011, 06:00 AM
with color bands :
http://www.pik-potsdam.de/research/resea...sColorBands.jpg (http://www.pik-potsdam.de/research/research-domains/transdisciplinary-concepts-and-methods/modsimenv/simenv/data/figures/2DVisColorBands.jpg)

with interpolated colors instead :
http://www.pik-potsdam.de/research/resea...isPureColor.jpg (http://www.pik-potsdam.de/research/research-domains/transdisciplinary-concepts-and-methods/modsimenv/simenv/data/figures/2DVisPureColor.jpg)

Mukund
06-22-2011, 11:17 AM
Ah, got it. Thanks!