Hi(gh)!

I feel that it is time to think about the global planetary setting for 
my "Port Whatmough" city project... so I started playing around with 
pigment patterns (to be used as isosurfaces later on) to create 
"physical maps" of that planet (i. e. Whatmough, named after the late 
John Whatmough, founder of "Extrasolar Visions", www.extrasolar.net).

The planet should be roughly Earth-sized (probably somewhat smaller, 
let's say 10,000 to 11,000 kms in diameter), with a slighter axial tilt 
than Earth (~14 degrees) and also less land surface, concentrated mostly 
in one main continent.

See attached images for what I've got using a special version of crackle...

...here's the code:

// beginning of code

camera
{
   location <0, 0, -2.5>
   look_at 0
   angle 60
}


#declare P_Terrain_1=
pigment
{
   crackle form <0, 0.3, 0>
   color_map
   {
     [0      rgb <0, 0, 0.3>]        // -10000 m
     [0.1    rgb <0, 0, 0.3>]
     [0.1    rgb <0, 0, 0.5>]        // -8000 m
     [0.2    rgb <0, 0, 0.5>]
     [0.2    rgb <0, 0, 0.7>]        // -6000 m
     [0.3    rgb <0, 0, 0.7>]
     [0.3    rgb <0, 0, 0.9>]        // -4000 m
     [0.4    rgb <0, 0, 0.9>]
     [0.4    rgb <0, 0.25, 1>]       // -2000 m
     [0.45   rgb <0, 0.25, 1>]
     [0.45   rgb <0, 0.5, 1>]        // -1000 m
     [0.475  rgb <0, 0.5, 1>]
     [0.475  rgb <0, 0.75, 1>]       // -500 m
     [0.49   rgb <0, 0.75, 1>]
     [0.49   rgb <0.25, 0.9, 1>]     // -200 m
     [0.495  rgb <0.25, 0.9, 1>]
     [0.495  rgb <0.5, 1, 1>]        // -100 m
     [0.4975 rgb <0.5, 1, 1>]
     [0.4975 rgb <0.7, 1, 1>]        // -50 m
     [0.5    rgb <0.7, 1, 1>]        // 0 m, sea
     [0.5    rgb <0, 0.8, 0>]        // 0 m land
     [0.5025 rgb <0, 0.8, 0>]
     [0.5025 rgb <0, 1, 0>]          // 50 m
     [0.505  rgb <0, 1, 0>]
     [0.505  rgb <0.5, 1, 0.7>]      // 100 m
     [0.51   rgb <0.5, 1, 0.7>]
     [0.51   rgb <1, 1, 0.9>]        // 200 m
     [0.515  rgb <1, 1, 0.9>]
     [0.515  rgb <1, 1, 0.65>]       // 300 m
     [0.525  rgb <1, 1, 0.65>]
     [0.525  rgb <1, 1, 0>]          // 500 m
     [0.535  rgb <1, 1, 0>]
     [0.535  rgb <1, 0.9, 0>]        // 700 m
     [0.55   rgb <1, 0.9, 0>]
     [0.55   rgb <1, 0.8, 0>]        // 1000 m
     [0.575  rgb <1, 0.8, 0>]
     [0.575  rgb <1, 0.7, 0>]        // 1500 m
     [0.6    rgb <1, 0.7, 0>]
     [0.6    rgb <1, 0.6, 0>]        // 2000 m
     [0.625  rgb <1, 0.6, 0>]
     [0.625  rgb <1, 0.5, 0>]        // 2500 m
     [0.65   rgb <1, 0.5, 0>]
     [0.65   rgb <1, 0.4, 0>]        // 3000 m
     [0.7    rgb <1, 0.4, 0>]
     [0.7    rgb <1, 0.2, 0>]        // 4000 m
     [0.75   rgb <1, 0.2, 0>]
     [0.75   rgb <1, 0, 0>]          // 5000 m
     [0.8    rgb <1, 0, 0>]
     [0.8    rgb 0.5]                // 6000 m
     [0.85   rgb 0.5]
     [0.85   rgb 0.65]               // 7000 m
     [0.9    rgb 0.65]
     [0.9    rgb 0.8]                // 8000 m
     [0.95   rgb 0.8]
     [0.95   rgb 0.95]               // 9000 m
     [1      rgb 0.95]               // 10000 m
   }
   translate <2, 0, 0>
   turbulence 0.5
   octaves 8
   omega 0.6
   lambda 2.07
   poly_wave 0.53
}

sphere
{
   0, 1
   texture
   {
     pigment { P_Terrain_1 }
     finish
     {
       ambient 1
       diffuse 0
     }
   }
   rotate y*0
}

// end of code

The problem is: I want to have wider lowlands (below 200 metres), but 
also a few, but defined mountain ranges rising above the snow line 
(above 4000 metres). With that crackle function I only get comparatively 
narrow lowlands and gently sloping highlands which rarely rise higher 
than 1000 metres.

What pigment/function of combination of functions would you recommend? I 
tried f_ridged_mf, but as the color_map repeated itself, it proved 
unsuitable.

The height distribution I need would resemble the graph of a cubic 
function, with a "saddle" around 0 (0.5 in the color_map)... I in fact 
tried several kinds of cubic functions (such as 
pow(x,3)+pow(y,3)+pow(z,3)), but the results were utterly weird and of 
no use for a physical map of a planet.

See you in Khyberspace!

Yadgar

Post a reply to this message

Attachments:
Download '2012-06-27 pigment test - whatmough, take 1.jpg' (180 KB) Download '2012-06-27 pigment test - whatmough, take 2.jpg' (81 KB)

Preview of image '2012-06-27 pigment test - whatmough, take 1.jpg'

Preview of image '2012-06-27 pigment test - whatmough, take 2.jpg'