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sysrpl
05-15-2005, 02:58 PM
Hi,

I am trying to create a procedureal bump map that creates an effect similar to the one below (except on all axis).

A 6 cm cube:

http://codebot.org/cube.jpg

I started out with a fractal noise texture applied as a color map to test its pattern and contrast.

Frequency: 3
Contrast: 5
Small Power: 2
Scale on all axis: 8 mm

Color Map:

http://codebot.org/color_map.jpg

This is what I am looking for in a bump map. Note the high level of contrast between the black and white areas.

When I move the color settings to the bump map channel here is what I get.

Bump Map:

http://codebot.org/bump_map.jpg

You can see the problem above. The transitions on the bump map from highs to lows appear as gradual rather than sharp edges. It does not have the contrast as in the color map.

I have tried several blending modes and additional layers, but have been unable to achieve the look of a bumped surface using a procedural that looks in any way like the image at the top of the page. I have read through the manuals, experimiented a lot and can't come up with any procedural setup to achieve the result I am looking for,

Could someone tell me of a setup that creates a procedural effect like the first image, or is Lightwave limited in is ability to create chaotic sharps edges using the out of the box procedurals?

Thanks.

Captain Obvious
05-15-2005, 03:48 PM
I tried it, and got the same problem. I baked the color channel and applied it as a bump map, and it worked perfectly. But there must be a better solution.

tischbein3
05-16-2005, 03:48 AM
Hi,

I am trying to create a procedureal bump map that creates an effect similar to the one below (except on all axis).

A 6 cm cube:

http://codebot.org/cube.jpg



You can see the problem above. The transitions on the bump map from highs to lows appear as gradual rather than sharp edges. It does not have the contrast as in the color map.

I have tried several blending modes and additional layers, but have been unable to achieve the look of a bumped surface using a procedural that looks in any way like the image at the top of the page. I have read through the manuals, experimiented a lot and can't come up with any procedural setup to achieve the result I am looking for,

Could someone tell me of a setup that creates a procedural effect like the first image, or is Lightwave limited in is ability to create chaotic sharps edges using the out of the box procedurals?

Thanks.

Use your procedural in bump then:

Add a gradient
Set blending mode to alpha (This is strange because it should be function with normal, but it doesn't)
keep input mode to previous layer
Use keys to filter out low values.
(you will need two keys, to soften out the edges a bit:

One where the bump starts and one where it has its maximum

)

sysrpl
05-17-2005, 07:19 AM
Use your procedural in bump then:

Add a gradient
Set blending mode to alpha (This is strange because it should be function with normal, but it doesn't)
keep input mode to previous layer
Use keys to filter out low values.
(you will need two keys, to soften out the edges a bit:

One where the bump starts and one where it has its maximum

)

Okay, I should let you know I am running Lightwave 7.5c.

What you said really made a lot of sense, until I tried it. The results wre not what you would expect.

Here is the gradient set to Alpha blending mode as you described.

http://codebot.org/gradient.jpg

And the result is this:

http://codebot.org/result.jpg

Much closer to the intended effect, but still 50% wrong. I tried playing around with other blending mode and different gradient setups.

As best I can tell something is terribly amiss with Lightwave here.

I really don't want to go into every detail of all the setups I tried, because there were so many, but suffice it to say that results with gradients layered on bump maps have very unexpected results.

One setup I tried (just to see what would happen) invloved these settings:

Start 1, End 0
Value 0%, Alpha 100%, Parameter 0
Value 100%, Alpha 100%, Parameter 0.5
Value 0%, Alpha 100%, Parameter 1

And the result was a cube with almost no bump, but with what looked like random hair thin scratches sparsely scattered about. I have read the manual, epxerimented for a few hours, and just don't get what is going on with these bump maps.

If you or anyone has any advice, can confirm this strange behaviour, know of someplace online to follow up on this problem, or can explain whats going on/have workaround, I would greatly appreciate it.

tischbein3
05-17-2005, 12:34 PM
well this is what I primarly thought, you wanted, and in fact it is even logical
(only clips away lower values, keep the (irregular) upper values)

and more logical than the other results.... My personal favorites are those with low texture amplitude value for fractal noise multiplied by high gradient values.

Agree something really...really bad is going on down there.........

toonafish
05-17-2005, 04:31 PM
a lot of the layer settings are ****ed up, not only the bump.

Lightwave is slowly falling apart.

tischbein3
05-17-2005, 06:53 PM
Could you specify wich layers / channels ?

spiroz
05-18-2005, 01:57 AM
the above mentioned method works great if one replace 'fractal noise' with 'turbulence' :)

toonafish
05-18-2005, 07:06 AM
-multiply and subtractive don't do what their name would make you think they do. Donno what they do though. With procedurals it doesn't work at all, and they behave differently in all channels like diffuse, lumiosity and transparancy

Try adding any layer on top of a color and set it to 255.255.255 and multiply. Nothing should change ( any value X 1 is the same as the original value ), but it does lighten the color.

-transparancy alpha's often don't work as expected. Try a procedural value layer set to normal and 255.255.255, add a B&W distance to object gradient on top of that, copy it, invert the keys and set it to alpha. It should completely disable the tranparancy of the underlying layer but it doesn't.

Or try a 50% value procedural in the transparancy channel, and add a completely white distance to object gradient set to alpha on top of that, donno what happens but it's not the way it should be. The same happens with procedurals.

Even simpler, just a transparancy procedural of 50 % ( value or crust with a coverage setting of 10 ). It should give you an alpha of 128 but doesn't.

-Gradients with bump as input channel don't listen to bump layers that are set to alpha, multiply or anything else then normal for that matter. I know this has always been the case, but still very annoying.

I could go on and on, but I think these examples are making my point.

I already reported this with Newtek. Let's hope this gets fixed someday.

tischbein3
05-18-2005, 10:36 AM
Well because all updates (from 8.01 to now) were allways focused on certain sections, and the surface editor wasn't part of these...I keep my fingers crossed.

(just a small note on the 128 /50% transparency bug: It didn't occured here.)

thanks for the info

toonafish
05-18-2005, 11:59 AM
(just a small note on the 128 /50% transparency bug: It didn't occured here.)



You're right, the problem was sitting between the screen and keyboard. I think my surface was double sided.

SplineGod
05-18-2005, 12:30 PM
Heres a cube with the kind of bumps I think youre looking for. I can verifiy that problems that youre having so heres another way to do it:
Load a blank black or white image and apply it to your surface in the bump channel using a cubic projection. Make sure to click automatic sizing.
In the image editor apply an image filter called Textured Filter.
Open the texture editor for that plugin and apply your fractal noise as you did
before with the contrast set high. If you plan to animate the procedural set it up as usual but be sure to check the animate filter box too.
Once you get the procedural the way you like then you can click on the thumbnail and it will allow you to save what you did as an image map which you can then reapply in place of the blank image.

automan25
11-23-2005, 08:47 AM
Althought this method works, it solves the problem by using a bitmap image. This negates the whole reason for using procedurals in the first place...the fact that they're resolution indendent.

This issue with bump maps is a big one. I'm a little shocked that this wasn't resolved in LW4 or earlier. Years ago I used Ray Dream Designer, a very basic and cheap 3D program. Bumps behaved as expected in that program...I would expect a program of Lightwave's caliber to not be struggling with this issue. I'm getting a little tired of using silly work-arounds to overcome basic misgivings in Lightwave.