How may Polygons is too many?

I know this is not fantastic modelling...

The saucer, cup and liquid were modelled from a cylinder primitive and smoothed to obtain a round appearance. As you can see the saucer alone has 4512 polygons, 9024 edges and 4514 vertices. At this level of detail, it renders well in my chosen software, but I'm just wondering If I go on to model the coffee pot, sugar bowl, cream jug and side plate will I be putting too much strain on the poor rendering package. In other words, what would be a good level of detailed softening for this type of model?

Oh! I forgot to add the coffee tray... I really don't want to create model sets with polygons in the 100,0000s mark or is this 'normal' (excuse the pun - LOL?) Sorry if my question seems stupid - but I am but a beginner...


Selina

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Comments

  • FlashGarciaFlashGarcia Posts: 191
    edited May 11

    I was thinking of asking this same question.

    Let's say I make a barrel of beer model and I want to be able to import it into Carrara, or Poser, but I don't want the polygon count to be larger than is adequate. Too few polygons would be trouble too. Is there some kind of adequate "polygon size chart" than someone has posted out there in Webland, for various objects?

    Sorry Selina for barging into your post but I would like to know the answers and suggestions for this too.

    Post edited by FlashGarcia on
  • SelinaSelina Posts: 288

    FlashGarcia I hope you get an answer soonwink

    It may just be that it depends on the level of surface detail required for placement in the rendering scene - far objects can have a much lower poly-count than those needed for closeups. So, perhaps answering my own question, model with the least amount of polygons necessary... I don't think there's a magic formula !  

    I don't know how many polygons DS can handle or Carrara for that matter... perhaps I'll model something with a tremendous amount of polygons just to see if I can break them !


    Selina devil

  • FlashGarciaFlashGarcia Posts: 191

    Gary Miller mentions good polygon limit size counts in some of his Hexagon videos, but I didn't take any notes while watching them. Time to watch some of them again.  It's like being in school again, but fun this time.

  • cdordonicdordoni Posts: 539
    Selina said:

    FlashGarcia I hope you get an answer soonwink

    It may just be that it depends on the level of surface detail required for placement in the rendering scene - far objects can have a much lower poly-count than those needed for closeups. So, perhaps answering my own question, model with the least amount of polygons necessary... I don't think there's a magic formula !  

    I don't know how many polygons DS can handle or Carrara for that matter... perhaps I'll model something with a tremendous amount of polygons just to see if I can break them !


    Selina devil

    I think you are asking a good question.

    In general, the lowest polygon count that will satisfy the rendering needs is best. When the camera is very close to the object you will need more polygons of course. Because LOD (level of detail) support is not consistent across rendering applications, you probably will need to create multiple resolution objects, for close renders and a lower one for further away, especially when you have LOTS of objects, like using replicators.

    I don't use DAZ Studio myself, although I seem to recall there was some plugin that would do LOD from a single object with higher resolution... it may even be built in now?

    Carrara has a plugin that will let you replace objects in a scene with another object, so you could have a lower resolution object for scene creation, or when using a bazillion repicated objects that will be seen from a distance. For a close in shot at render time you could swap out the low resolution version(s) for the higher ones.

    Hard to pin a specific # of polys on any object as a limit though.

  • ShawnDriscollShawnDriscoll Posts: 209
    edited May 12
    Selina said:

    As you can see the saucer alone has 4512 polygons, 9024 edges and 4514 vertices. At this level of detail, it renders well in my chosen software, but I'm just wondering If I go on to model the coffee pot, sugar bowl, cream jug and side plate will I be putting too much strain on the poor rendering package. In other words, what would be a good level of detailed softening for this type of model?

    The resolution of the cup and saucer meshes look fine for that close of a camera shot. Farther away camera shots don't really need meshes at that resolution. For those kinds of models, the proportions of the meshes come into play more when you are UV mapping and painting/texturing the models.

    Anyway, 5,000 polys is a good enough number for such objects. 50,000 polys is normal for organic models like dogs/cats. 150,000 for humans/aliens. I rarely hit the smooth button more than twice in Hexagon for my models. Video game content uses a 1/25 of the polys for its models, since normal maps replace most polys.

    Post edited by ShawnDriscoll on
  • Wee Dangerous JohnWee Dangerous John Posts: 1,020

    Personally what I look at is the shape of the object, if you look at the cup - the rounder you make it the better (so it does not give you sharp edges). The lines going across the object does not need so many, you'll need edges for the handle, and a few to keep the shape (helps with mapping as-well - stops texures looking stretched). Select an edge, Loop it then press the back space key.

    The chamfer option does come in handy.

  • SelinaSelina Posts: 288

    Thanks cdordoni, ShawnDriscoll and Wee Dangerous John for your helpful comments.

    I will certainly look at proxy objects, disolving edges, chamfers and keeping my poly-count circa 5-8k for cups, saucers, plates, sugarbowls and the like!


    Selina smiley

  • ShawnDriscollShawnDriscoll Posts: 209

    Curved edges on objects can be controlled using just three edges, depending on how close they are spaced together before smoothing.

    polygon_smoothing.jpg
    606 x 591 - 49K
  • seegsonsseegsons Posts: 90
    edited May 13

    Curved edges on objects can be controlled using just three edges, depending on how close they are spaced together before smoothing.

    true inside Hexagon

    when I export a mesh to Carrara it's still fine but dare to export subdivision surfaces to OBJ I can easily get millions of polygons (shock)

     

    Post edited by seegsons on
  • ShawnDriscollShawnDriscoll Posts: 209
    seegsons said:

    Curved edges on objects can be controlled using just three edges, depending on how close they are spaced together before smoothing.

    true inside Hexagon

    when I export a mesh to Carrara it's still fine but dare to export subdivision surfaces to OBJ I can easily get millions of polygons (shock)

    Huh? You already have millions of polys when smoothing, no matter what the app.

  • AscaniaAscania Posts: 325
    seegsons said:

    Curved edges on objects can be controlled using just three edges, depending on how close they are spaced together before smoothing.

    true inside Hexagon

    when I export a mesh to Carrara it's still fine but dare to export subdivision surfaces to OBJ I can easily get millions of polygons (shock)

     

    What is the shock there? Subdivision creates more geometry that is kept in a "potential" state within the program. The .obj format can't handle cage geometry with a flag "subdivide this", so for export it has to be turned into "real" geometry.

  • richmcleanrichmclean Posts: 56
    edited May 15

    Hi @Selina, I would recommend trying to not use subdivisions for non-organic objects (and even organic objects if they do not bend).  Make use of the surface attribute called smoothing angle in combination with edge bevels and use enough geometry so that visible profiles are not blocky (based on how close the camera will get to the object).  FYI....The robot that I just modeled in Hexagon, has 64,000 polygons.  There are some areas that I wished I had used a few more (but live and learn).  

     

     

     

    smoothShaded.jpg
    521 x 869 - 174K
    Post edited by richmclean on
  • SelinaSelina Posts: 288

    I would recommend trying to not use subdivisions [but] make use of the surface attribute called smoothing angle in combination with edge bevels and use enough geometry so that visible profiles are not blocky (based on how close the camera will get to the object).  FYI... The robot that I just modeled in Hexagon has 64,000 polygons.

    Hi,

    Thanks for your contribution to the question... when you talk about surface smoothing angle - I presume you are talking about surface normals? I thought this kind of visual 'smoothing' was done in the renderer (DS or Carrara) and using the smoothing levels can give an idea of the effect when modelling in Hexagon? Or have I got it wrong?

    Great model of the Robinson's Robot by the way!


    Selina

  • ShawnDriscollShawnDriscoll Posts: 209
    edited May 16

    The renderer can only do so much. Your model has normals for facets, and normals for edges. They all have to be set right. Otherwise, strange shaded corners on your model.

    Post edited by ShawnDriscoll on
  • richmcleanrichmclean Posts: 56

    Hi @Selina, your right, I am referring to the smoothing parameter for the surface property for the renderer.  Just a way to cheat so you do not have to dynamically subdivide everything (which quadruples your poly count for every subdivision level).  I have attached a pdf showing an example (my cup design is not as nice as yours).  Not perfect but hopefully it gets the point across.

    Also.....thanks for the comment about the Robot.  I was checking out the new Lost in Space on netflix which got me thinking about how I much I enjoyed the original Dr Smith and Robot which got me modeling good old B9.  I have him rigged and surfaced now I need to animate him (including the lights).  I hope you check it out when I am done.

     

     

     

    pdf
    pdf
    CupModelUsingSmoothingAngle.pdf
    146K
  • SelinaSelina Posts: 288
    edited May 16

    Okay Boys,

    I got it wrong; 'surface normals' is not what I meant, rather Vertex Normals which to the lay person such as myself refers to 'smoothing' of the angles of the surrounding polygons to a given vertex. As I illustrate in my image to the right the number of polygons used for the curved object is merely 10 - yet it has a rounded surface appearance, even close to the camera! I think this is what richmclean meant with his comment above. In my example the smoothing factor is carried across to Carrara and renders beautifully I don't know about DS4.

    However, if I were to save the model as an .obj then I think it would be subdivided accordingly by Hexagon. As a matter of interest how many polygons will the robot have if saved as an .obj I wonder?

    ShawnDriscoll you talked about facet normals, Face Normals which govern the orientation of the surface polygon (I'm already familar with this - thanks). Some renderers will not render the backside of faces - Carrara is not one of them. I have yet to do research on Edge Normals and what they govern.

    Thanks to your pithy comments boys and lack of 'how to', I found I had to do my own research (which is great - don't get me wrong) on the subject not quite knowing what I was seeking. But, as not everyone is an avid self-motivator like myself, I post my findings in case anyone else wants to know.

    Once again - thanks boys - your 'guidance' is most welcome.


    Selina

    Post edited by Selina on
  • cdordonicdordoni Posts: 539
    edited May 16

    Hexagon does not have crease edges, if I recall. In order to get a hard edge, the mesh has to be split (disassociate) along the edge that needs to be hard. 

    Shawn's method above is useful if you dont need an extremely sharp edge. It can create a nice "soft" edge beween surfaces.

    Post edited by cdordoni on
  • AscaniaAscania Posts: 325
    cdordoni said:

    Hexagon does not have crease edges, if I recall. In order to get a hard edge, the mesh has to be split (disassociate) along the edge that needs to be hard. 

    Shawn's method above is useful if you dont need an extremely sharp edge. It can create a nice "soft" edge beween surfaces.

    Incorrect. It is available in the Smoothing Tool

  • SelinaSelina Posts: 288

    Hi cdordoni,

    Thanks to my recent research I would have to disagree in that it is not necessary to disassociate along an edge to get a crisp, hard delineation between polygons...

    I illustrate my finding both by the small thumbnail rendered to the right in Carrara and the screen grab of Hexagon below.

    Now I'm not saying that ShawnDriscoll's method is any less valuable. I wouldn't dare proffer my findings as authoritative (I'm only a beginner!) But, you can clearly see that what was once a cube, remains a cube though it has taken on the appearance of a smoothed object with a very hard edged circular end!

     

    I'm still looking for 'Edge Normals...' I'm now more familiar with Vertex Normals and Face Normals - Thanks boys, once again!


    Selina

  • richmcleanrichmclean Posts: 56

    @Selina, because I export my obj with a smoothing value of 0, my robot has 64,000 polygons.  If I export with a smoothing value of 1, my robot would have 256.000 polygons.  That would make the model much harder to UV map and rig and animate and use.  Usually your renderer application will allow you to subdivide your model during rendering.  That allows you to keep the model as lower poly while not rendering.  Not sure how Carrara handles that since I use Daz.

    Smoothing Angle is not a value you set in Hexagon.  It is set on your material in your renderering application.  The smoothing angle value does not increase poly count like subdividing does.  It takes the normals into account and renders a smooth edge across 2 edges based on their angle.  I provided an example in the pdf document. 

    Your picture is a demonstration of subdividing which quadruples your poly count for every smoothing level.  

  • richmcleanrichmclean Posts: 56
    edited May 16

    Here is my 1250 polygon cup rendered using the "render only" SubD level setting that I mentioned above.  Hope it helps.

     

     

    CupLip.jpg
    731 x 665 - 48K
    Post edited by richmclean on
  • cdordonicdordoni Posts: 539
    edited May 16
    Ascania said:
    cdordoni said:

    Hexagon does not have crease edges, if I recall. In order to get a hard edge, the mesh has to be split (disassociate) along the edge that needs to be hard. 

    Shawn's method above is useful if you dont need an extremely sharp edge. It can create a nice "soft" edge beween surfaces.

    Incorrect. It is available in the Smoothing Tool

    When you export the file, are the edges still sharp? Doesn't the smoothing control subdivision only, not normals?

    Post edited by cdordoni on
  • SelinaSelina Posts: 288

    Your picture is a demonstration of subdividing which quadruples your poly count for every smoothing level.

    Which picture are you referring to? If you mean the blue one; it comes across to Carrara exactly as modelled in Hexagon with 10 polygons, 20 Edges and 12 Vertices. Any extra 'subdivision' is done on the fly for rendering purposes only - there is no fixed subdivision of the mesh and I can extract, dissolve or move edges as I desire to change the resultant shape! Also, in Carrara I can turn off 'smoothing' and the shape returns to its original cuboid state.

    The other image (the purple one) shows the same with a smoothing 'break' applied to get a hard edge - this too can be manipulated and changed at will in Hexagon or returned to being a cube. Now because it has a hard edge, it displays with a greater number of isoparms which DO GET CONVERTED to actual geometry when brought across to Carrara.

    By its very nature, modelling curves in Hexagon using vertices connected by straight edges and filled with polygons, subdivision of one form or the other is absolutely necessary, whether it's Surface Subdivision as conducted in the renderer or Tessellation as applied to the mesh (geometry).

    I hope I've clarified my current understanding of the subject, but just to dot the i's and cross the t's...

    You said,
    "Smoothing Angle is not a value you set in Hexagon." - yes I know
    "It is set on your material in your rendering application" - not where Carrara is concerned it is applied to the model itself
    "The smoothing angle value does not increase poly count like subdividing does" - yes it does in memory terms
    "It takes the normals into account and renders a smooth edge across 2 edges based on their angle" - yes I know (see my comment above on Vertex Normals)
    "Your picture is a demonstration of subdividing which quadruples your poly count for every smoothing level" - No it's not - there's no actual tessellation to the model itself! There is subdivision but this is held in memory of the software renderer as is the case with SubD in DS (or whatever it's called!)

    Thanks for taking the time to engage in the discussion, but I feel you didn't understand or read what I'd said earlier sad


    Selina

  • SelinaSelina Posts: 288
    cdordoni said:

    When you export the file, are the edges still sharp? Doesn't the smoothing control subdivision only, not normals?

    You can see what I did above, the object comes into Carrara exactly as modelled in Hexagon with sharp edges - why not have a go yourself ?


    Selina

  • ShawnDriscollShawnDriscoll Posts: 209
    edited May 17
    Selina said:

    ShawnDriscoll you talked about facet normals, Face Normals which govern the orientation of the surface polygon (I'm already familar with this - thanks). Some renderers will not render the backside of faces - Carrara is not one of them. I have yet to do research on Edge Normals and what they govern.

    Good, you found it. Vertex Normal is what it is called. By the way, I do all my edge creases in Carrara after exporting as OBJ from Hexagon. I haven't found a modeling app that does it as well as Carrara does. A lot of apps want to just smooth the entire model and make edges on them by moving edge loops closer together, or by using vertex weight maps.

    Most of my modeling is lo-res that just needs basic creased edges applied.

    Post edited by ShawnDriscoll on
  • ShawnDriscollShawnDriscoll Posts: 209
    edited May 17
    cdordoni said:

    When you export the file, are the edges still sharp? Doesn't the smoothing control subdivision only, not normals?

    OBJ exporting will collapse the geometry, so it looks like this in Carrara with bad smoothing normals (which confuses the Phong shading). So creasing the edges in Carrara fixes things. Maybe the latest Carrara is not allergic to this?

    smooth_break.jpg
    720 x 405 - 69K
    Post edited by ShawnDriscoll on
  • ShawnDriscollShawnDriscoll Posts: 209
    edited May 17

    The other way is to bunch edges together, and then smooth. But this is mostly for smooth organical modeling. Nothing that's hard-edged mechanical modeling.

    smooth_break2.jpg
    800 x 600 - 122K
    Post edited by ShawnDriscoll on
  • cdordonicdordoni Posts: 539
    edited May 17
    Selina said:
    cdordoni said:

    When you export the file, are the edges still sharp? Doesn't the smoothing control subdivision only, not normals?

    You can see what I did above, the object comes into Carrara exactly as modelled in Hexagon with sharp edges - why not have a go yourself ?


    Selina

    I have, which is why I made the comment, see Shawn's comment with a picture of what happens in Carrara, which is why crease edges can only be applied in Carrara. I think some of the confusion lies in a double meaning for smoothing. Smoothing can refer to subd's or normals.

    Post edited by cdordoni on
  • SelinaSelina Posts: 288

    OBJ exporting will collapse the geometry, so it looks like this in Carrara with bad smoothing normals (which confuses the Phong shading). So creasing the edges in Carrara fixes things. Maybe the latest Carrara is not allergic to this?

    Hi ShawnDriscoll,

    I haven't noticed any particular difficulties with importing Hexagon's OBJ objects and I'm running Carrara Pro 8.5 64-bit as you can see from the image below.
     

     
    Thanks for all your help and encouragement

     
    Selina

  • SelinaSelina Posts: 288
    cdordoni said:
    Selina said:

    Why not have a go yourself?

    I have, which is why I made the comment...

    I'm sorry you were not able to do what I as a beginner can do, perhaps you need to do some more experiments - Happy investigations !!!

     
    Selina

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