hello,

in a new image i want to render rust on a cylindrical surface. approach until now:
rust should be a function with a pattern, pattern should be an height_field or a
normal and this should be used with a cylinder.

my readings were Chris Hormann's water tutorial and some other web-material. but the
results are bad: i even do not get a height field. using normals Povray says a numeric
expression is missing.

i thought about isisurfaces, but they are too slow.

can anybody tell me if my approach is wrong way or if i made other programming
mistakes.

more information follows if wished (tell me what, please).

best regards

the construction until now is:

#declare fn_rostbeule = 
function{ pattern {
bozo turbulence 0.65
                        octaves 6  omega 0.7 lambda 2 
                        rotate<10,20,0>
                        scale <0.3, 0.4, 0.2>*30
}}//pattern,function

#declare fn_rostbeule_hf = 
function {
	y-fn_rostbeule(x,0,z)*0.5
}
object{ [..]
texture{
      pigment { [..]
}} //pigment, texture
texture{
      pigment { [..]
}} //pigment, texture
	normal {
		bump_map{
		function {
			fn_rostbeule_hf(x,y,z)*10
		}
		scale 10
		}
	}
	translate y*3
	rotate y*-75
}

Post a reply to this message

Wasn't it marabou who wrote:
>hello,
>
>in a new image i want to render rust on a cylindrical surface. approach until 
>now: rust should be a function with a pattern, pattern should be an height_field 
>or a normal and this should be used with a cylinder.

If you want to use a normal, there's no reason to wrap the normal
function around the cylinder. Just apply the normal to the cylinder
unwrapped.

cylinder {p1,p2,r
  texture {Whatever}
  normal {bozo turbulence 0.65
    octaves 6  omega 0.7 lambda 2 
    rotate<10,20,0>
    scale <0.3, 0.4, 0.2> * 30
  }
}
-- 
Mike Williams
Gentleman of Leisure

Post a reply to this message