oh shit its mr vaughan himself can we get a sneak peak on the next workbook?
oh shit its mr vaughan himself can we get a sneak peak on the next workbook?
still letting the dust settle on Volume 2
@aregvan It looks like you're on the right track.The key to clean cylinder intersections is to match the number of segments on both shapes near the intersection. Try matching the wall segments on the critical part first and adjust the perpendicular loops second. The alignment doesn't have to be perfect. Close enough should be good enough. (Page 171 has a discussion about cylinder intersections on hydrants.)Manually pushing or sculpting geometry into place isn't that accurate and can become very time consuming. Block out the shapes, match the segments near the intersections and rely on tools to generate the geometry. After the basic shapes are correct, run a Boolean union operation, add support loops around the intersections with a bevel or chamfer operation and merge down any left over geometry. Use the gap between the support loop and the base of the intersecting shape to take up any difference between the cylinders. Repeat as necessary to add additional details.This example is more illustrative and the amount of geometry required to hold the shapes on your hydrant may be different.Looking at images of Bayard hydrants, there's a couple variants and they have different shapes. One has this barrel shape and the other has a uniform outer diameter. The one with the uniform diameter has a curve at the back of the stand pipe that (when viewed from the side) makes it look like the diameter of the stand pipe is larger than the diameter of the outlet. Cross check several references when working through the block out to make sure the basic shapes are correct and the rest should fall into place.
@aregvan It looks like you're on the right track.The key to clean cylinder intersections is to match the number of segments on both shapes near the intersection. Try matching the wall segments on the critical part first and adjust the perpendicular loops second. The alignment doesn't have to be perfect. Close enough should be good enough. (Page 171 has a discussion about cylinder intersections on hydrants.)Manually pushing or sculpting geometry into place isn't that accurate and can become very time consuming. Block out the shapes, match the segments near the intersections and rely on tools to generate the geometry. After the basic shapes are correct, run a Boolean union operation, add support loops around the intersections with a bevel or chamfer operation and merge down any left over geometry. Use the gap between the support loop and the base of the intersecting shape to take up any difference between the cylinders. Repeat as necessary to add additional details.-Looking at images of Bayard hydrants, there's a couple variants and they have different shapes. One has this barrel shape and the other has a uniform outer diameter. The one with the uniform diameter has a curve at the back of the stand pipe that (when viewed from the side) makes it look like the diameter of the stand pipe is larger than the diameter of the outlet. Cross check several references when working through the block out to make sure the basic shapes are correct and the rest should fall into place.
@guitarguy00 Not a problem.That loop part starts out as a circle with a segment count that's matched to the area it will attach to. The back end of this part doesn't matter that much since it will be lost in the Boolean operation.Land the part between two of the vertical segments and use those segments as support loops. Add support loops to the sides and cut across the flat to give the extra edge loops some where to run out on.I think the best answer to the question of how it works with so little geometry is: using the surrounding geometry as
support for every part that's added on. It could be made more
accurate with more geometry but the question is how accurate is accurate
enough?Some of these examples use very little geometry because it makes it easier to see the edge flow and it emphasizes that most shapes don't require a ton of geometry. What's right will depend entirely on what you're trying to model and how accurate it needs to be. A background prop doesn't need to be perfect it just needs to be passable. What's passable will depend on the project and the artist. So the examples are more of a baseline or a starting point. Another thing that can help is playing to the strengths of how an object was made and what it was made out of.Most hydrants are cast in
either bronze or iron. Metal casting is still a very hands on process in many parts of the world. It's only in the exotic and high precision
casting where machines take over most of the process.
That's slowly changing but it's still common for a lot of hand work to
go into molding, shake out, grinding and blasting. By the time
something leaves the foundry there's a good chance that there's some
superficial or cosmetic imperfections. It's just the nature of the
process. The roughness and texture is part of what makes an honest
casting.Casting patterns also need a lot of draft (taper) and soft shape transitions. Otherwise it's too difficult to pull the pattern out of the sand molds without destroying the mold in the process. This means that most high volume and low cost castings are going to have softer shapes than something that's machined out of a billet. It's a similar sort of thing with injection molded plastics and blow molded plastics.There's always going to be some distortion on a sub-d mesh and it comes
down to a question of where to hide it. Sometimes the distortion is
averaged out over a wide area and sometimes it's constrained to a
smaller area. You can use this basic understanding of how things are made to try and figure out where's the best place to hide distortion in the mesh and how wide support loops and edge widths need to be.The smaller cylinders on the side don't have dedicated support loops on the stand pipe side of the mesh. The wall of the stand pipe is acting like a support loop and the support loop that's on the base of the small outlet is doing all of the work. So the distortion is averaged out across the transition.As for where to merge down existing geometry, it depends on the shape and how it's reacting to the subdivision. When using chamfer to add a support loop around the base of an intersection, the base of the intersecting object (the inside of the support loop) usually stays where it's at. Running a Boolean operation there might be some stray geometry on this
inside loop. Merge that down to the verts on the intersecting object.
The outside loop is usually (but not always) merged down to the verts on
that object to maintain shape accuracy. Whatever happens between these
two loops usually doesn't matter that much and that's where the
difference between the intersecting objects is averaged out.I think the sample you posted looks fine. At a glance everything seems smooth and the transitions are soft. What's "right" depends on the project. If there's a lot of little details that need to be blended into the standpipe then it's going to require more geometry.
I can't stress enough the fact that waviness is not incorrect. It is the natural result of correctly baked normals between two cylindrical objects with a non-equal # of sides. If you don't want it, just match the number of sides:
I'm a bit ashamed of the issues I'm having as it's perhaps not as complex as some of the other shapes in here but I've been trying to model this partitioned plastic cover over the window.Here are my low polys:Close up from the sideFrom aboveand here it is subdividedIt's not perfect but it's the closest I've gotten while keeping each part about the same width and mostly similar. I'm wondering if I'm way off with this? My steps are these roughly.
What car modell is it? Do you have higher res pictures. If it sub-ds good and there's no big issues. go for it.
there are no hard and fast 'rules' when it comes to modeling somethin"Modeling Cars In Polygons"
What do you guys think would be the best way to model this type of braided rope? I'm kind of out of ideas.this is pretty much my best try so far
Outside of specific project requirements, stock 3D certification programs and technical edge cases, there really isn't anything wrong with using triangles and n-gons in subdivision modeling. Flat surfaces are arguably the least effected by messy topology. As long as the corners are supported and the surfaces are co-planar then it should subdivide without causing any major problems. If a mesh is easy to edit and subdivides cleanly, without any major smoothing errors, then it's passable. There's a point where done is better than perfect.As an example: here's four subdivision previews (left column) and four topology strategies (right column) can anyone spot the subtle differences and match up which subdivision preview belongs to which mesh?The four topology samples (right column) are:Triangles and quads.N-gons, triangles and quads.Quads only (manual cleanup)Quads only (tool generated)The matching subdivision previews are directly across from the mesh samples.For most high poly baking models, what happens on the flat areas between the edge loops doesn't make much difference. As long as the shape intersections and the support loops are properly structured the flat areas will remain flat. They generally subdivide and bake without causing any major issues.There are edge cases like highly reflective surfaces where the quality of the mesh does effect some things but whether or not this is relevant for a project is something that can be validated with some test bakes.The n-gon mesh is easier to edit but there are some cases where curves need the stress from triangles to help pull the edge loops into shape.Manually cleaning up a mesh to make it all quads is a major pain and often a waste of time. Avoid throwing more work into bad geometry. If it's broken enough that it needs a lot of manual cleanup then it's probably worth rebuilding correctly.Take the time to plan out the shapes and match the segment counts between adjacent shapes. Plan out the edge flow so edge loops can be added without effecting critical shapes.Here's an example of how planning out the edge flow and working through the shapes will result in all quads with minimal cleanup. The segment count is a little higher than I would generally recommend for a game model of this scale but the assumption is that the corners on the USB ports need to be curved. This could have been done using a wider support loop on the corners but leaving it in shows how to deal with similar shapes that require more geometry.Start out with the basic shapes and define a clear path for the support loops to run out on. Match segment counts to minimize the amount of geometry required to support the shape. Rely on tools for creating basic geometry, curves and edge loops whenever possible.The support loops around the Micro USB port are added with a chamfer operation and run out between the two USB ports. The support loops inside the USB port are added with a loop cut and run out to the sides of the case and around the Micro USB port topology.Use a chamfer operation to add the support loops around the face of the USB port. Adjust the segment count on the circular case geometry and bridge the edge loops so all of the segments are connected. This side is now complete. The other side will have the same number of segments.Use the same segment count for the opposite side of the case and the button cut out. There's a support loop that holds the shape for the outside of the case and it eats up one segment of the button so an edge loop needs to be added between the case and the button to equalize the segment count. Additional support loops could be added to the right side of the button if necessary. Bridge the faces to close the geometry. The basic shape is now complete.Add additional support loops around the button and outside of the case. Move the center loops back to set the button depth and the seam depth between the case and face plate. Extrude the rest of the shape out to form the rest of the case. All quads and no manual cleanup work to remove triangles or n-gons. How much geometry is required will depend on the desired shape accuracy.Subdivision modeling is about planning out the edge flow and shape intersections while choosing the right trade-offs between efficiency and shape accuracy. If there's no hard requirement for all quads then use the minimum amount of geometry required to hold each shape. Triangles and n-gons that aren't causing smoothing problems are fine. In most cases (if they aren't causing smoothing errors) it's not worth the time to edit them out.Here's a comparison of two extremes: a mesh that leverages a lot of n-gons and a mesh that has been made all quads for compliance. The n-gon strategy is easy to work with but may not pass some strict QA / QC processes for stock 3D. The all quads compliance strategy hits this metric but the over optimized edge flow makes it difficult to add or remove loops. The geometry is locked in.What's right depends on the project and part of the process is balancing technical demands with the art process and time management. A product visualization model is going to have different requirements than a background prop for a mobile game. Narrowing down the scope of the project will help determine which strategies will work best.If a project genuinely requires all quad geometry: Take the time to plan the edge flow and block out the shapes ahead of time. Match each shape's segment count with surrounding geometry and run out edge loops where they won't disturb adjacent shapes.The mesh you already have shows a good compromise between efficiency and accuracy. There's only a couple spots that could cause problems with subdivision and even then it might not be a problem if the smoothing errors aren't visible when baked out and textured.Add the rest of the support loops and subdivide the mesh to see if there are any major smoothing problems. If the mesh looks good with subdivision then it's fine.
hey guys, what should i do to build the curving pipe with all those convex on it like the ref. 1&2. and this is what I got for now. I dont now if i do it in the right way? and what should i do next to get that kind of convex.
Given there is such a limited amount of vertical native geometry, how would you avoid distortion on the cylindrical parts? Also when you weld the side cylinders to the main vertical one, do you weld all the verts of the side cylinders to the vertical one, or vice versa?
This is one example after your advice and others one here too:
Perfect! Simple and to the point. This has helped me more than I was expecting!
Problem is, I begin modeling before I even have the basic shape, and always thinking it's harder than it really is.
And what do you mean by "rely on tools to generate the geometry"?
This truly helps for this project and future ones!
You are right; things are more simple than we perceive them as.
I always stayed away from boolean operations, but seems its inevitable for any detailed mesh play.
Thank you again for a great discussion, Frank.
So i know this is a problem that happens when your low poly doesn't have enough subdivisions to meet with your high poly especially on round corners. The problem is visible only on couple of spots of the model and i was wondering if there would be a problem if i added some edges only on the areas that need topology. Is this a terrible solution if i want to avoid extra polygons? is there any other way instead of just subdividing the whole model ? Thank you!
Hey there, buddy. You have two issues here. The first one you circled is waviness, most prominent on the top one you circled, and is discussed in detail here: https://polycount.com/discussion/81154/understanding-averaged-normals-and-ray-projection-who-put-waviness-in-my-normal-map#latest
You should absolutely read through the entire thread, but here's the short version: Waviness happens because your highpoly's cylinder sides varies from the lowpoly cylinder sides. The waves captured aren't errors. They're the output of what you input. You can do one of two things: Limit the amount of sides on your highpoly to match the lowpoly, and chamfer the edge instead of subdividing it...
Or increase the sides to your lowpoly around that edge to the degree that you can't discern the waves from the desired rendering distance. If you choose this method, I would do it like this (in blue)
Note that simply adding those verts won't change the result. They need to follow the curve of the highpoly.
The dark edges won't be helped from that though. They are something else entirely, and happen because the visible lowpoly captured a part of the highpoly onto the normal map that allows you to see an edge at such an angle that you'd never see it on the highpoly from that same angle.
Below are three examples. First is highpoly only, second is what you want in order to hide the dark edge, third is what you have.
Thank you very much! I was waiting for someone to give a good piece of advice for couple of days and i couldn't wait because i wanter to proceed with the project. I made the changes right away after i got home and honestly the results are great thanks again!
There is no more skewing and the topology looks ok i guess.
Not sure how to solve this polygon flow in this model I'm doing just for practicing. Just starting so not a good distribution of polys yet. A few lines showing how to do it better will be appreciated. Thanks
Front view of the model:
Here are my low polys:
Close up from the side
and here it is subdivided
It's not perfect but it's the closest I've gotten while keeping each part about the same width and mostly similar. I'm wondering if I'm way off with this?
My steps are these roughly.
What car modell is it? Do you have higher res pictures. If it sub-ds good and there's no big issues. go for it.
Here are a few clearer ones:
The subdivided mesh seems mostly fine, some minor artifacts where it's the densest so I'll have to spread the edges out a bit and tweak the overall shape here and there but I'm always worried I'm doing things terribly wrong.
Also, holy cow, thanks for that link! Very useful stuff there.
It's probably a bad habit but often when I run into ugly reflections, I create a higher density mesh of the broken part (usually with inefficient topology though) and use the Blender modifier "shrinkwrap" on my "more" efficient lowpoly mesh to wrap it onto the higher density mesh underneath and that takes care of things sometimes (and creates seamless reflections across separate parts as well) although it creates some extra work.
this is pretty much my best try so far
OMG, thank you so much you definetely need to combine all your tips in great tutorial, very inspiring
I'm stuck on this one braided band on the handle of an axe in this concept art and was wondering if anyone had any ideas how to go about modeling it? I tried doing this coil of alternating half cylinders but it didn't overlap properly.
Wow, those are great tips. Really helps. I figured it had something to do with helices but didnt know how many or where Dx.
I'm working on a hand-painted game character from concept and the first one seems low poly enough. Thanks!
Similar issue regarding cylindrical/round details repeated in this thread countless times, same solution. You need a lot more base geometry. If you're adding a support loop to the bottom of the planar flat detail (on the right), you'll get a gnarly pinch on the curved detail on the left.
A good way to establish curvature/base geometry without affecting the model, or redoing the model rather, is to just delete all unnecessary edges/support loops, double check your smoothing groups to be correct, and add a turbosmooth modifier with smoothing groups checked. This will keep all your hard edges, and round out any faces that are set up with smoothing groups properly. You may find that you'll have to tweak your SGs in a certain way that doesn't break the geometry, like adding multiple SG's on a flat planar area to get the correct result.
and this is what I got for now. I dont now if i do it in the right way? and what should i do next to get that kind of convex.
As I understand you, you're looking for the ribs on the tube going from the 90° bend pipe to the wall.
For segments and setup, I chose an even number of segments (6), then an edit poly modifier to delete the end caps:
Now a turbosmooth modifier and an edit poly modifier. In the edit poly, I select one edge, hit loop, then a dot ring selection that I will delete:
This has essentially doubled the smoothness of the curve without adding uneccessary segments around the pipe. Repeat that step 4-5 times to end up with this, a tube with a very smooth curve, but low segments:
RIB TIME! In a new edit poly modifier, select one ring, then dot loop, convert selection to polygons, and extrude. The extruded polygons should be square.
Now just turbosmooth that result and yer done.
This is where my love for modifiers in max comes in. I can go back to the spline and change the thickness, or grab verts of the spline and move them around with an instand result
Notice how on the original the sides are the same width, i don't know hot to make that cut and keep it like that.
In this example, I've laid down a surface (green mesh) to which, I've decided to extend the border of and curve it in a way so the slope acts like a border wall (grey mesh). The problem I have is that the topology of the two is different enough to present me with this problem:
Due to the edges not accurately connecting with each other, I'm left with tiny holes in between. My question is: what would be the best solution to this? I'm certain I'll need to recreate the border wall but I'm wondering which would be the best way to do it because I'd like to retain the kind of pretty, uniform quad size and topology I got with it so I don't have issues UV mapping it later on.
Anyhow, I'd really appreciate any sort of help with these two concerns I posted. Thanks all!
Just to clarify, the original piece was done with sub-d.
For both of your examples my suggestion would be the same, you will have to model it thinking about how the hole shape will look like, figuring out things like. Should i extrude it and then bevel?, or bevel and then extrude? etc. This way you don't get problems like your first images. Doing simple-ish models like those is usually very easy with sub-d.
When i was first starting i didn't know that sub-d was a thing, then i learned and it melted my mind just as it melts topology. Here is a good introduction.