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ksp
01-14-2009, 03:24 PM
(ok this may be simple but i'm stumped)

(i am transferring a texture from layers to nodes)

in my bump chanel (layers) i have a procedural controlled by a black/white image above it which is set to alpha.

how do i achieve the same in nodes?

JBT27
01-14-2009, 03:48 PM
You plug what would be your alpha image/procedural into Bump Amplitude.

Julian.

ksp
01-14-2009, 04:14 PM
thanks. thats halfway there. this masks the procedural but is opposite to what i want. i have tried inverting the imageand tried using an invert node.

i attach a pic to show where i have got to so far. i am using a b/w image to control breaks in masonry.

(btw i was reading this thread - http://newtek.com/forums/showthread.php?t=70895 - but it got too confusing so i thought i would start from the bottom up with my bumps)

ksp
01-14-2009, 04:45 PM
i have ended up with this.

ok - my next 2 questions


1 - i have a gradient - if it was a layer i could adjust the layer opacity - what is the equivelant?

2 - if i plugin a node to the color does it overwrite the color i entered in the box (just under the nodes button on the main texture panel)

MooseDog
01-14-2009, 06:45 PM
try this...instead of using the bump from your alpha image, use the luma into the bump amplitude. like your first pic, only slightly different.

btw, i've noticed that nodes do not handle greyscale bump maps the same way as layers. i think the math under the hood is different.

Sensei
01-15-2009, 03:57 AM
"post #3 picture..."

?!?!
Bump vector output connected to Bump Amplitude Scalar?!
You're really asking for troubles...
If it really should be this way (not understand this logic), you should get bump vector, connect it to node that gives you vector length, and then put to Bump Amp... otherwise it simply make no sense..

JBT27
01-15-2009, 06:02 AM
i have ended up with this.

ok - my next 2 questions


1 - i have a gradient - if it was a layer i could adjust the layer opacity - what is the equivelant?

2 - if i plugin a node to the color does it overwrite the color i entered in the box (just under the nodes button on the main texture panel)

Have you managed to make any headway with this ksp?

As MooseDog suggests, it does seem that nodal bumps are calculated differently, and to be blunt, I still get better results with layered sometimes, but that's as likely to be inexperience with nodes as anything.

Julian.

JBT27
01-15-2009, 06:46 AM
See if these help - two procedurals on the same object controlled by a Turbulence node's alpha controlling the bump amplitude.

Julian.

ksp
01-30-2009, 01:21 PM
thanks for all the help.

a few things have just clicked into place now.

[2 screenshots below showing where i have got to so far.]

1st - basic nodes setup when i cracked it.
2nd - what i've got now.

JBT27
02-15-2009, 11:40 AM
That's good! Glad the proverbial penny has dropped - hate it when it doesn't, love it when it does!

Your node network is giving me a headache :D but the surface is nice.

Julian.