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Topics - Paolo_Giandoso

Pages: [1] 2
1
In the parameters of a substance, is it possible to create a new Input Parameter which is a Integer1 slider and it is only stepping through odd numbers?
If I select step 2 it only goes through the even numbers, even if my min is set to 3.

Tanks
Paolo

2
Hi
Does anyone know if it is possible inside the Pixel Processor (or FX-Map node) to numerically calculate Integrals?
Specifically I was thinking about the Incomplete elliptic integral of the 2nd kind.

Thanks
P

3
Hi all
I have been trying to solve this problem for a while which I need for my project. Is there anyone with a strong passion for math and geometry and with time to spare who is willing to give me a hand? :)

I want to create, using the Pixel Processor, a gradient representing all the Normals to a semi ellipse (origin centered and with the 2 semi-axis parallel to the x and y axis respectively) defined by 2 attributes,  Height (b) and Width (a).
Something like this.

orginated by something like this

The parameter Height is basically the minor semiaxis and Width the major semiaxis multiplied per 2.

Every point in the plane should get the value of the angle formed by the x axis and the one normal to the ellipse that passes for it.


It has been quite complicated for my non mathematical brain and so far I only managed to find partial solutions. I solved it using an FX map (the images below) rotating a very thin line around the ellipse circumference exactly in this way https://commons.wikimedia.org/wiki/File:Normal_lines_to_the_ellipse.svg#/media/File:Evolute1.gif but the result is not as good as a gradient done with the pixel processor, as it creates a stepped effect even with thousands of iterations (ugh) and if I make the line thicker (tried that too) it becomes even more stepped.





I also solved it using a distance node on a regular angular gradient masked with the ellipse alpha. This works too, to a point, but is not perfect either. The result is stepped and wobbly (I think because of the jagged edge of the ellipse shaped mask).




Can anyone help me see the light? I'll be forever thankful :)

Ellipse equation:
      y²/b² + x²/a² = 1
Point P on the Ellipse:
      for every x where -a<xP<a
      yP= b√1-(x²/a²)
Point K where the NORMAL in P to the ellipse meets the x AXIS:
      xK = xP [1-(b/a²)]
      yK = 0
Equation of the normal to the ellipse in P:
      (a²x/xP) - (b²y/yP) = a² - b²
Angle  between the Normal and the X Axis meeting in the point K:
       atan2 (xK- xP,yK- yP,) (in Radians)
       atan2 (xK- xP,yK- yP,)/2Pi  (in Turns)


4
How can I create these dots that drive the coordinates of the node from the 2DView (the ones indicated by the arrows in the attached picture)?

5
Hi all. :)
I'm trying to write an equation using the Pixel Processor for an angular gradient with an arbitrary center, therefore I imagine using the atan2 function at some point I guess.
I have as inputs the coordinates of the Center and of 2 points A and B (where B is simply A mirrored along the y axis), and what I want to obtain specifically is a angular gradient that is fully black at point A and white at point B, so some form of precise clamping (the rest of the pie can be black). So far I had no luck with this.
Is there anyone who can offer some guidance?
Thanks a lot!
Paolo

6
Hi
I noticed several times in different situations that the curve node gives a black output when the image input gets updated (like for instance a input made from a linear gradient connected to a histogram scan, of which I am controlling the position with an exposed attribute).

Moving any of the control points in the curve node fixes the problem, but when the input image gets modified again it starts all over again.
Is there any solution for this? Am I doing something wrong?

Thanks
P

7
Hi.
 I am trying to create a procedural stone arch shape in my substance. It's a half circle sitting on top of a rectangle.
I'd like to make so that if I scale the rectangle width of height the circle moves with it, always sitting on top, while keeping it's 2:1 proportions.

I'm trying to find out if there is a way to make a shape B sit always on top of another shape A no matter how much you scale A, similarly to a point Constrain in Maya.
I see that the transformation 2d Matrix has 2 values indicating how many time a shape is tiled on the X and Y, and that there is also an offset x and y parameter governing the translation. How can I connect them with an Expression to obtain the effect I'm looking for?
Thanks
Paolo

8
Hi all
I'm trying to understand how to set up the Tile Generator or the Tile Sampler so to create a row of 2 shapes distributed accordingly to this pattern A-B-B-B-B-B-B-B-B..-A
Where Shape A is both in first and last position and in between there are multiple shapes of type B (the number will be controlled by the user, so there could be 3 B shapes as well as 20)

I want to use it to create a stone "Balcony" rail, where the first and last shapes are cubes and the mid shapes a n number of cylindrical shapes. IMM from ZBrush are usually set up in this way.

If someone can give me some suggestions I will be grateful
Thanks
Paolo

9
Is there a way to emulate Maya's Bend Deformer in Substance Designer?
https://knowledge.autodesk.com/support/maya/learn-explore/caas/CloudHelp/cloudhelp/2018/ENU/Maya-CharacterAnimation/files/GUID-557246DD-CF0F-4BDB-BDD0-47947A97BC94-htm.html

Where you can take a straight shape as an imput (lie a rectangle) and bend it gradually, where 0 is equal to the shape in its base state and 1 is equivalent to the result of the Cartesian to Polar node?

Many thanks
Paolo

10
Hi all
I have 2 questions about tiling materials.
I'm creating a plaster wall with a lot of damage and I plan to use the substance for a building with a very specific UV layout in City Engine.
A: Any advice on how to create a material which tiles perfectly but by changing the seed it only modifies the inside part of the tile? So that you can create several iterations that tile perfectly but still are different in the inner part (different plaster damage patterns and bricks being revealed in different points for instance)
B: Any advice on how to make a substance that tiles both with itself and the mirror of itself?
Any guidance will be greatly appreciated.
Many thanks
Paolo

11
Hi all
Does the "shape splatter" node completely replaces the "tile sampler", the "tile random"and the "tile generator" nodes?
Is there any reason to use them as of now?
Many thanks
Paolo

12
Hi
Is it possible to detect if a normal map was exported for OpenGL or DirectX just by the map alone?

Many thanks
Paolo

13
Hi all
Is there a way to alter the color of all the bricks that touch a specific shape, like a window or a door or the edges of a building, like in the images below?
Many thanks
Paolo

14
Hi all
Can anybody suggest a workflow for bending the bricks pattern in a radial structure when they get close to the windows/door like in the images I attached? I wanted to keep the arches size interactive but I have no idea how to have the bricks layout react to that.
Any suggestion would be greatly appreciated :)

Many thanks
Paolo

15
Hi all

I have been making some tests with Substances and Arnold 5.
So far my biggest doubt is the value to give to the Specular Color (or specular Weight parameter as it is a multiplier) when you are dealing with a non metal material or a partially metallic material like a rusty metal.

I assumed at the beginning that the correct way was to leave both Specular Weight and Specular Color set to 1 and "white", as the Arnold 5 guide says: "When Metalness is enabled, the Specular Weight and Specular Color only control the edge tint, while the Base is still affected by roughness."

Since in the PBR workflow from substance there is always a map connected to Metalness, even if the map is black Metalness SHOULD BE enabled (although maybe for enabled they mean a non fully black map, this is really unclear to me).

Since I am dealing with non metallic substances (a roof, a  patch of mud and rusty metal), I assumed that specular color and weight would have had no influence on the material.
However the results from leaving specular set to the max were way to bright though for a correct realistic PBR.
So I made a wedge of 3 different substances(a roof, a  patch of mud and rusty metal) with a specular value of 1 (max), 0.25, and 0.
The result shows clearly that the specular value does influence the look of non metal materials a great deal, as shown by the images I linked, which are the beauty, the diffuse pass and the specular pass. Not only in the edge tint of the metal bits (as shown in the rusty substance) but also everywhere.

Am I doing something wrong?
Given these results, my question is:What is the correct value to give to the Specular Weight/Color parameters for a correct PBR?

Many thanks
Paolo

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