Noise Functions and Relative Scale



  • THE POST BELOW IS MORE THAN 5 YEARS OLD. RELATED SUPPORT INFORMATION MIGHT BE OUTDATED OR DEPRECATED

    On 26/06/2010 at 20:31, xxxxxxxx wrote:

    User Information:
    Cinema 4D Version:   11.5 
    Platform:   Windows  ;   
    Language(s) :     C++  ;

    ---------
    Hi everyone.

    I would like to scale the noise functions that I am using in the same manner as the relative scale setting in the Noise shader.  Could anyone point me in the right direction for how to accomplish this.

    If you create a material in C4D and add a noise shader to the color channel.  Then go in to the noise shader and set the noise to x = 100 y = 0 and z = 0.   you will see that the noise becomes straight lines.  So each part of the vector adjusts the scale of the noise in each direction.  I want to do the same to the noise functions that I am using on my geometry.

    Any help you could offer would be greatly appreciated.

    Thanks.

    ~Shawn



  • THE POST BELOW IS MORE THAN 5 YEARS OLD. RELATED SUPPORT INFORMATION MIGHT BE OUTDATED OR DEPRECATED

    On 28/06/2010 at 06:39, xxxxxxxx wrote:

    Which noise functions are you using? In general it's just a matter of scaling the individul vector components of the position vector passed to the function.

    cheers,
    Matthias



  • THE POST BELOW IS MORE THAN 5 YEARS OLD. RELATED SUPPORT INFORMATION MIGHT BE OUTDATED OR DEPRECATED

    On 28/06/2010 at 06:47, xxxxxxxx wrote:

    Hi Matthias,   right now I am just using Turbulence to test my results...

    Here's what I have..

    for (int i = 0; i < pointCount; i++)
    	{   
    		Real factor=0;
    		
    		Real turbx, turby, turbz;
    		Vector norm = GetVertexNormal(i, polyCube, &nb);
      
    		turbx = Turbulence((points[i] * scale.x + shift.x),time, octaves, abs) * strength;
    		turby = Turbulence((points[i] * scale.y + shift.y),time, octaves, abs) * strength;
    		turbz = Turbulence((points[i] * scale.z + shift.z),time, octaves, abs) * strength;
    			
    		Vector turb = Vector(turbx, turby, turbz);
    		
    		//Turbulence
    		if (bc->GetLong(SPACEROCK_NOISETYPE) == SPACEROCK_TURBULENCE)
    		{
      
    			points[i] = Mix((points[i] * turb) * norm, points[i], amt);
    			
    			//points[i].x = Mix(points[i].x * turbx, points[i].x, amt) * scale.x;
    			//points[i].y = Mix(points[i].y * turby, points[i].y, amt) * scale.y;
    			//points[i].z = Mix(points[i].z * turbz, points[i].z, amt) * scale.z;	
    		}
      
      
      
    	}
    

    The results I am getting are less that impressive.    It looks more like a bumpy ball than a rock.  HAHA

    here's an image.

    When you scale the noise in for example the x component of the vector for a noise shader, you get more ripples than little bumps like I am getting.    Any thoughts on how I could achieve that ripple effect with geometry that is achieved by using a noise shader?



  • THE POST BELOW IS MORE THAN 5 YEARS OLD. RELATED SUPPORT INFORMATION MIGHT BE OUTDATED OR DEPRECATED

    On 28/06/2010 at 09:21, xxxxxxxx wrote:

    What I meant is to scale the vector you pass to Turbulence().

    Something like this:

      
    //the current vertex  
    Vector p = padr[i];  
      
    //relative noise scaling  
    p.x *= scale_x;  
    p.y *= scale_y;  
    p.z *= scale_z;  
      
    //get the scaled turbulence  
    Real t = Turbulence(p, 2, FALSE);  
    

    Use the scaled  turbulence values to move the vertices along their normal for instance.

    cheers,
    Matthias



  • THE POST BELOW IS MORE THAN 5 YEARS OLD. RELATED SUPPORT INFORMATION MIGHT BE OUTDATED OR DEPRECATED

    On 28/06/2010 at 10:05, xxxxxxxx wrote:

    Oh...  now I see.. thanks again Matthias!

    ~Shawn



  • THE POST BELOW IS MORE THAN 5 YEARS OLD. RELATED SUPPORT INFORMATION MIGHT BE OUTDATED OR DEPRECATED

    On 28/06/2010 at 10:24, xxxxxxxx wrote:

    LOL..  it's official Matthias.  You just became my favorite person on the planet.    Two weeks of toying and reading and arguing with code were solved in your last post.   It's amazing what we overlook when we are frustrated.  LOL

    Thanks again.   If I lived anywhere near you I'd buy you a beer.

    ~Shawn


Log in to reply