Page 2 of 2 FirstFirst 12
Results 21 to 39 of 39
  1. #21
    Member lsscpp's Avatar
    Join Date
    May 2006
    Location
    Firenze
    Posts
    2,047
    Originally Posted by moony View Post
    Nice illustration, but what are the vectors like at the start (the textured cube is shown - but the vectors are only shown after they have had 0.5 subtracted).
    they point in +1 x,y,z starting from origin 0,0,0
    Everything's relative. Even saying "Everything's relative".



  2. #22
    Member lsscpp's Avatar
    Join Date
    May 2006
    Location
    Firenze
    Posts
    2,047
    Originally Posted by alborz View Post
    Yes! that's my problem as well! that is why i tried to add emission and bump to my original material! But maybe the best way for these materials is post processing in Photoshop (to add extra glare?)
    As Secrop said, to keep it in the physical realm, no emission, but rather you should shoot more light, and let the Filmic tonemapping do the magic. You often discover how lower the albedo of materials have to be set!
    Let's suppose you use emission in the shadertree. Then you place the lipstick in a dark corner of the scene. What happens? You probably have to tweak the shader again!
    In Secrop nodetree, to get brighter glitters, you might want to get rid of diffuse compnent (letting the glossy shine alone) and maybe crank up the ligt blue in the color-ramp.
    Everything's relative. Even saying "Everything's relative".



  3. #23
    Originally Posted by lsscpp View Post
    As Secrop said, to keep it in the physical realm, no emission, but rather you should shoot more light, and let the Filmic tonemapping do the magic. You often discover how lower the albedo of materials have to be set!
    Let's suppose you use emission in the shadertree. Then you place the lipstick in a dark corner of the scene. What happens? You probably have to tweak the shader again!
    In Secrop nodetree, to get brighter glitters, you might want to get rid of diffuse compnent (letting the glossy shine alone) and maybe crank up the ligt blue in the color-ramp.
    but if i want to keep it in the physical realm, shouldn't i keep the diffuse component since all materials have a Diffuse reflection?



  4. #24
    Member
    Join Date
    Apr 2012
    Posts
    1,790
    Originally Posted by lsscpp View Post
    they point in +1 x,y,z starting from origin 0,0,0
    All of them can't though - since the voronoi texture will randomise their direction. I was wondering what the distribution of vectors looked like before subtraction of 0.5 which made the distribution spherical around the origin.

    Would it have been a hemispherical distribution with it's base on the surface?



  5. #25
    Member Secrop's Avatar
    Join Date
    Dec 2011
    Location
    Berlin
    Posts
    1,846
    Originally Posted by lsscpp View Post
    they point in +1 x,y,z starting from origin 0,0,0
    exactly!

    Originally Posted by alborz View Post
    but if i want to keep it in the physical realm, shouldn't i keep the diffuse component since all materials have a Diffuse reflection?
    Not necessarily. It depends on the type of material. Materials like this one can be made of different substances.. The flake particles are normally metallic, which the glossy alone should be enough. Some are also mixed with other substances, like wax, epoxy, etc. The diffuse is just for mimic that part, and can be removed if not needed.

    The only thing important here, is to mimic how the flakes are oriented. The trick I posted is just pratical and fast. But also, as I stated, variations can be made.



  6. #26
    Member Secrop's Avatar
    Join Date
    Dec 2011
    Location
    Berlin
    Posts
    1,846
    Originally Posted by moony View Post
    All of them can't though - since the voronoi texture will randomise their direction. I was wondering what the distribution of vectors looked like before subtraction of 0.5 which made the distribution spherical around the origin.

    Would it have been a hemispherical distribution with it's base on the surface?
    The vectors can be pointing to anywhere inside that cube, starting from the origin; since the color components of the voronoi-cell are uniformly distributed in the [0, 1] interval.

    For a more exact 'hemispherical distribution', one need to normalize the result after the subtraction of [0.5,0.5,0.5], which will turn the cube into a sphere; and then flip the vectors that are pointing to the negative of the normal. This is fairly a bit more complex, but can be done.
    Last edited by Secrop; 12-Oct-17 at 12:33.



  7. #27
    Member
    Join Date
    Apr 2012
    Posts
    1,790
    Originally Posted by Secrop View Post
    The vectors can be pointing to anywhere inside that cube, starting from the origin; since the color components of the voronoi-cell are uniformly distributed in the [0, 1] interval.

    For a more exact 'hemispherical distribution', one need to normalize the result after the subtraction of [0.5,0.5,0.5], which will turn the cube into a sphere; and then flip the vectors that are pointing to the negative of the normal. This is fairly a bit more complex, but can be done.
    Ah - I get it now - thanks.



  8. #28
    by normailze you mean make unit vectors => L = 1?

    but this won't change direction or angle !

    thanks
    happy cl
    Nice 3D models = 25 % K.I.S.S + 25 % common sense + 25 % Inspiration + 25 % Knowledge
    Win 10 64 bits / Thanks and a Happy 2.79 with Cycles



  9. #29
    Member Secrop's Avatar
    Join Date
    Dec 2011
    Location
    Berlin
    Posts
    1,846
    Originally Posted by RickyBlender View Post
    by normailze you mean make unit vectors => L = 1?

    but this won't change direction or angle !
    More or less... It won't change the vectors direction, but as soon as you add the Normal vector, the result it's quite different.

    For example, if all vectors were very small, and we added the normal vector to them, the result would not be very different from the normal vector itself, no matter the small vectors direction; If they were bigger than the unit lenght and we add the normal, we will even get vectors pointing to bellow the surface.



  10. #30
    Originally Posted by Secrop View Post
    More or less... It won't change the vectors direction, but as soon as you add the Normal vector, the result it's quite different.

    For example, if all vectors were very small, and we added the normal vector to them, the result would not be very different from the normal vector itself, no matter the small vectors direction; If they were bigger than the unit lenght and we add the normal, we will even get vectors pointing to bellow the surface.
    SO now i have two new problems!

    Click image for larger version. 

Name:	Model.png 
Views:	15 
Size:	312.5 KB 
ID:	502080

    i have a weird shading on the bottom part of the cap (cap is just a simple cylinder) -> which is only visible in camera view <-

    Also i don't see the reflections on the label (in camera view) but i see them in normal view port!!

    I don't know why everything gets messed up when i try to render in camera view!

    My label should look like the cap, shiny with lots of reflections...

    Click image for larger version. 

Name:	IMG_20171017_124125.jpg 
Views:	2 
Size:	243.4 KB 
ID:	502081



  11. #31
    having a decent product shot with mild reflections is something i need
    Last edited by alborz; 17-Oct-17 at 16:04.



  12. #32
    Member Secrop's Avatar
    Join Date
    Dec 2011
    Location
    Berlin
    Posts
    1,846
    Blend file needed for better review. From the screenshot it's not possible to determine the cause, since most of the settings are hidden (and the problem can be anywhere... like wrong light path config, wrong object visibility, and since the problem is with reflections, it can be anywhere else outside of your mesh!)



  13. #33
    Member
    Join Date
    Apr 2012
    Posts
    1,790
    The reflection problem on the cap could be due to smooth shading issues across a sharp boundary.

    Do you have edge loops at the bottom of the cap to smooth the transition out?

    Name:  126119i58238CA26D4744F0.png
Views: 68
Size:  87.4 KB



  14. #34
    Originally Posted by Secrop View Post
    Blend file needed for better review. From the screenshot it's not possible to determine the cause, since most of the settings are hidden (and the problem can be anywhere... like wrong light path config, wrong object visibility, and since the problem is with reflections, it can be anywhere else outside of your mesh!)
    Here is the blend file (without HDRI)
    the object's dimensions are based on real life size so that's why it is so small.

    Model.blend



  15. #35
    Originally Posted by moony View Post
    The reflection problem on the cap could be due to smooth shading issues across a sharp boundary.

    Do you have edge loops at the bottom of the cap to smooth the transition out?

    Name:  126119i58238CA26D4744F0.png
Views: 68
Size:  87.4 KB
    Yes i do! but when i change my camera position that glitch also moves (become bigger or smaller)



  16. #36
    Member
    Join Date
    Mar 2006
    Location
    Kiel, Germany
    Posts
    3,526
    The glossy areas are reflecting your shadow catcher... Make it invisible to glossy rays.

    Name:  18-10-2017 18-32-30.png
Views: 61
Size:  48.5 KB
    Asus Sabertooth 990 FX | AMD FX-8350 @ 4.6 GHz | 32 GB RAM | GIGABYTE GeForce GTX 1070 OC 8 GB
    Win 7 Ultimate x64



  17. #37
    Originally Posted by IkariShinji View Post
    The glossy areas are reflecting your shadow catcher... Make it invisible to glossy rays.

    Name:  18-10-2017 18-32-30.png
Views: 61
Size:  48.5 KB
    Oh shoot! great catch! also please feel free to point out to any node problems or other problems you see! i would really appreciate it



  18. #38
    thank everyone for helping

    i changed the glass to glossy with low IoOR (clear plastic) and removed solidify and i think it looks closer to the real image!

    Click image for larger version. 

Name:	Model.png 
Views:	8 
Size:	506.1 KB 
ID:	502177
    Last edited by alborz; 18-Oct-17 at 16:56.



  19. #39
    Member dudecon's Avatar
    Join Date
    Sep 2007
    Location
    Camarillo, CA, USA
    Posts
    223
    Followed the instructions, went a bit crazy, and woke up to this:
    Click image for larger version. 

Name:	T076SwHRWcq2tYiSgsLfgbq7_RUa2TaL6_0pCqcS9fJmaDGPzDwirunvevaCPKrc.jpg 
Views:	2 
Size:	146.7 KB 
ID:	502275
    Commissions, 3D prints, and Mechanical Engineering. If you appreciate my contributions, support me on Patreon!



Page 2 of 2 FirstFirst 12

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •