LDD/POV-Ray random colors

[Balrog]

I have searched and found nothing that answers my question. If this has been answered before, please point it out to me.

I want to make a render of a Lego creation. So far, the model contains two colors. I thought about replacing the one color by random colors, but doing this by hand and brick by brick is a feasable task. it would be optimal if certain brick colors could be excluded. Is there a chance to do this in either LDD or POV-Ray?

Alternatively, if this is possible with LDraw, I would give this a shot.

Any ideas??

[Darats]

In PovRay, the rand() function generates random numbers. You can use it in your RGB colors definitions, and you will have random colors each time you render you scene.

[Balrog]

In PovRay, the rand() function generates random numbers. You can use it in your RGB colors definitions, and you will have random colors each time you render you scene.

So I edit the .pov file and edit the substitute color for e.g. black from a fixed value to rand()?

I don't want to render a color in a single random color, but many bricks of the same color in many different colors. From what you described, it won't work the way I want it.

Edited August 13, 2015 by Balrog

[Darats]

OK then, don't edit the color definition itself, but replace each brick color definition by a rgb value with the random values. I guess it should work.

[Balrog]

I'll try that when my current render is finished.

update:

This doesn't work. I tried replacing one of the color codes with rand(). This, of course, doesn't work. I checked the documentation and found I need to declare a seed, which I did. Still, POV-Ray gives this error: "Parse Error: Cannot assign uninitialized identifier." with highlight to the line with the rand.

This would be one of the lines in the .pov file:

ldd_3023(array[1]{RAND(R1)},array[1]{0},array[1][12]{{0,0,1,0,1,0,-1,0,0,-1.1999994516372681,1.5999996662139893,-4.4000000953674316}})

opposed to this:

ldd_3023(array[1]{26},array[1]{0},array[1][12]{{0,0,1,0,1,0,-1,0,0,-1.9999998807907104,0.63999998569488525,-4.4000005722045898}})

Also, your first suggestion doesn't work as well, because I obviously cannot replace the RGB value by a simple rand. But it would work like this:

#declare ldd_black = rgb <rand(R1)/255,rand(R2)/255,rand(R3)/255>;

This is acceppted by POV-Ray, but does not result in a color change. Very strange. At this point, giving LDD2POV-Ray a certain different number to replace the Lego Black with, still results in the color not being replaced. So there is something else broken here.

Edited August 13, 2015 by Balrog

[Darats]

#declare ldd_black = rgb <rand(R1)/255,rand(R2)/255,rand(R3)/255>;

This is what I meant. I haven't really been into details but, that's what I was thinking of. A random value devided by 255 for each R, G and B color.

This would work I guess, but this will give you the same random color for each black brick, try to directly implement the rgb color for each brick.

I guess you are using ldd2pov, and I don't know the kind of pov file it generates so I cannot try myself.

As a workround, If you where using Ldraw, I would simply write a quick code in C++ or VBA to edit the ldraw file and change randomly color values. I don't know if this would be feasable with LDd...