Symbolic Posted May 26, 2007 Share Posted May 26, 2007 Hi, I am trying to create that shader for a container. One of the problems is the rust and the scratches. As part of this I am trying to create a procedural texture... that will have a noise texture and this noise texture will go from gray to white... this will act as a BIAS for an image based texture... Since it is a different issue... I thought that it will be good idea to start a new topic... I am really sorry if I am doing a mistake by starting this post... DaJuice posted a file explaining the use of the Paint SOP and colour attributes. I modified the file a little bit and kind of created a controlable noise that goes from A to B... But the problem is that... It works based on SHIFT VOPs... and the values that I added are very strange... It is very hard to control the system... When the character of the noise changes... most of the values has to be configured.... How can I create a more controlable procedural component? This is a test render. proc_teapot.mov This is the hip file. distribution_rnd_v1r9_post.hip Thanks. Quote Link to comment Share on other sites More sharing options...
DaJuice Posted May 26, 2007 Share Posted May 26, 2007 (edited) To get a growing type effect (I'm just guessing this is what you're going for) you can again use the Shift Range VOP. Just move the source min & max values in tandem. My previous example of using Shift Range VOPs was probably a little convoluted and difficult to control. Take a look at the file. To see the effect right on the teapot, set the viewport to VEX Shaded, open up the display properties (hit 'd' in the viewport) and jack up the Level Of Detail to something like 5. Now play with the slider on proc_noise1. Hope this helps. distribution_updated.hip.tar.gz Edited May 26, 2007 by DaJuice Quote Link to comment Share on other sites More sharing options...
Symbolic Posted May 26, 2007 Author Share Posted May 26, 2007 Hey DaJuice, Thanks for the help... once again This was really fast... I can not describe the happiness when you make a post and wait... wait... keep refreshing and staring at the screen I have looked at the file... it seems very good. Now I have to sleep for a while... I will look at it again when I wake up. Thank you very much. By the way... I was not complaining about your previous file... it was ment to be a solution to another problem... helped me alot indeed... and also inspired me for that procedural noise growth... I am very new to the VOPs... this is the problem... i am familiar with only a few of the VOPs... and this makes the process long and the result uncontrolable... Quote Link to comment Share on other sites More sharing options...
Symbolic Posted May 26, 2007 Author Share Posted May 26, 2007 Hi, One small question... How I can transpose a parameter from in between a range to another range... like if I have a slider that works very good between the values of -5 and 5... but I want this range to be FIT inside the range of 0 to 1... like the fit command in expressions... ex: fit($AGE,-1,10,0,1) -1 and 10 is the first range... 0 and 1 is the corresponding new range... How can I do that in VOPs? Thanks Quote Link to comment Share on other sites More sharing options...
Symbolic Posted May 27, 2007 Author Share Posted May 27, 2007 Hi, Another small question... I need to create an outline of a noise pattern... Like the "Edge Detect" filters... so that I can use it as a bump-map around the noise itself... I am working on it right now... probably it has something to with copyin the noise pattern... shrinking it a little bit... and subtracting it from the original pattern... I am not sure... Thanks. Quote Link to comment Share on other sites More sharing options...
sibarrick Posted May 27, 2007 Share Posted May 27, 2007 (edited) Hi,One small question... How I can transpose a parameter from in between a range to another range... like if I have a slider that works very good between the values of -5 and 5... but I want this range to be FIT inside the range of 0 to 1... like the fit command in expressions... ex: fit($AGE,-1,10,0,1) -1 and 10 is the first range... 0 and 1 is the corresponding new range... How can I do that in VOPs? Thanks Shift Range VOP edit: gets me every time, why isn't call the fit range VOP??? Edited May 27, 2007 by sibarrick Quote Link to comment Share on other sites More sharing options...
DaJuice Posted May 27, 2007 Share Posted May 27, 2007 (edited) Shift Range VOP crashes the party yet again. Append one to your control Parameter VOP. In this case all you need to do is revert the Parameter VOP to the defaults of 0-1 and set the Destination Minimum to -5 or somesuch in the new Shift Range. Edited May 27, 2007 by DaJuice Quote Link to comment Share on other sites More sharing options...
Symbolic Posted May 27, 2007 Author Share Posted May 27, 2007 Hi this is the edge detect and bump result. As you can see I still have the white artifacts. I do not know why... Maybe my way of creating the outline out of the noise is not the right one. Here is a render and the *,hip file. May be you can have look at the VOP network and help me optimize it. Thanks. bump_noise_edge_v1r2.hip Quote Link to comment Share on other sites More sharing options...
DaJuice Posted May 27, 2007 Share Posted May 27, 2007 Clamp SOP at the very end of the vopnet usually fixes that, but there is probably a better way of preventing it from happening in the first place. Quote Link to comment Share on other sites More sharing options...
Symbolic Posted May 27, 2007 Author Share Posted May 27, 2007 Hi DaJuice, Thanks. But clamp does not seem to be working... Shift Range VOPedit: gets me every time, why isn't call the fit range VOP??? Wow! Worked Perfect!!! Thanks! Quote Link to comment Share on other sites More sharing options...
DaJuice Posted May 27, 2007 Share Posted May 27, 2007 Hmm, worked here. Quote Link to comment Share on other sites More sharing options...
Symbolic Posted May 27, 2007 Author Share Posted May 27, 2007 (edited) Hmm, worked here. Ok... But clamping my lighting model will make the speculars and everything related to the lighting model dull... and you know... clamped... But the strange thing is that... when I leave the values untouched... it works for the teapot... but does not work for my container... Maybe it is about the UVs... or something like that... Edited May 27, 2007 by Symbolic Quote Link to comment Share on other sites More sharing options...
DaJuice Posted May 27, 2007 Share Posted May 27, 2007 Actually forget the clamp (and you are right, it will fuck your speculars). Altbighead was right in the other thread, you need to normalize the vector coming from displacenml1. Quote Link to comment Share on other sites More sharing options...
Symbolic Posted May 28, 2007 Author Share Posted May 28, 2007 Actually forget the clamp (and you are right, it will fuck your speculars). Altbighead was right in the other thread, you need to normalize the vector coming from displacenml1. It worked... Thanks! I did not see the post by "Altbighead"... some how... and I kept piping that normalize always in the wrong place... thanks for reminding me about the other post... it works great now... Quote Link to comment Share on other sites More sharing options...
nisha Posted May 4, 2008 Share Posted May 4, 2008 how do you do the same... thing with a texture... say i have a rust texture... and i want it to grow over another texture... Quote Link to comment Share on other sites More sharing options...
Symbolic Posted June 2, 2008 Author Share Posted June 2, 2008 (edited) how do you do the same... thing with a texture... say i have a rust texture... and i want it to grow over another texture... I am away from my Houdini computer... but you might use a noise map... one just like the file posted here... and use it to manipulate the opacity (Alpha) of the texture... RGB texture (R, G, goes into the color output noise map (Alpha) goes into the Opacity. when the noise map is black... there will be no texture... when some areas are white... we will be able to see the texture through... Edited June 2, 2008 by Symbolic Quote Link to comment Share on other sites More sharing options...
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