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0:00
[Music] when you open a 3D software especially the kind used for animation you'll see that everything is made of these wir likee structures with loops spanning the entire structure this is the topology of 3D mesh a topology refers to Arrangement and flow of these vertices edges and faces that make up a 3D mesh it dictates the structure of your model and plays a pivotal role in determining how
0:37
well it forms animates and subdivides now once you get a bit nerdy and uh gain some hands-on experience you'll start recognizing topology in everything around you not just in 3D softwares similar to real world structures these vertices and polygons Define the topology of an object in 3D the more polygons you have the smoother the model and allowing for more more intricate details but impacting the performance it's going to be more laggier going to perform slower so reduce
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these vertices and polygons and you'll start seeing Jagged mes but the model can perform in real time using less resources of computer even handling large number of these objects a crowd of people let's say while maintaining a good computer performance is quite possible and easy for gaming engines the next time you play a game with crowds like FIFA or WWE and notice as you see in this footage John Cena and Randy Orton have all the muscles and everything while all the people in the
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crowd doesn't even have fingers so understand the developer were not lazy they were just managing polygon counts to ensure that the game performs well and investing more resources in characters like John Cena and Randy whom players pay for basically and not these people so in summary denser topology results in high resolution model and when things get high resolution needs more resources the good thing is that you're living in fortunate times where you don't have to model and
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create entire character in just 50 polygons so 15 to 20 years ago this is how the characters used to look like in 3D games her entire body is less than 1/10th of resolution of this sandwich from current gen game Starfield Now understand even though this game might look visually outdated to current generation kids it used to be a big deal for us it inspired the whole action RPG genre and continues to influence many things to date so all the times are more forgiving now
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with powerful Hardware it's still crucial to respect and manage measure resolution despite technological advancements so nowadays games are incredibly details and expectations are even higher and even there are new things like AR and VR so managing 3D meses is still a thing so forgive me for assuming everyone here is new to 3D and I might State some obvious things but it's necessary to get few points across now I'll start with few absolute basic examples
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because there's a whole wide range of audience on my channel so I need to be a bit more considerate you never know where this video video is going to land so let's assume this is uh leg just bear with me now there's an Armature underneath it which is driving its motion so if I try to move it it's not going to move this object much because it's like a Lego piece at this moment literally there's nothing in it but now if you go to edit mode and add one more Loop here then you'll see
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at least this is like bare minimum required for making a legs motion but now if you want this to have some more smoothness you can add few more Loops here so that there are more Loops to support this deformation of the knee and then you keep on adding basically from here on I can uh do anything I want so now it's like officially a leg and then if I P some more attention leg only bends in one particular angle so if you come to think about it we need more Loops here and
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less Loops here so if I was working in a polygon constraints or something then I can just bevel this here and I have more Loops to bend but now the problem is here we have five points so this makes it uh and gone so it's quite easy to fix just take this one and connect it here you have cords everywhere now so this is just for an example don't go on and adding an Armature and then start modeling all right and then there is no end to it you can just keep on adding Loops if you
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want and keep detailing your model the more Loops there are the more it's going to Def well and can carry more details so let's say if you have some muscles here or if you want to put some corrective shapes then for that you need some more Loops here so these things might would help with it let's share smooth this and then let's say if you wanted to have some more muscular details here you can just tweak few of these loops and shape it more like a leg so I'm just going to
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try and eliminate every triangle or none I see now that I have proper quarts everywhere if I want to add some more details to this object I can just press controlr and keep on adding more details and this is going to be quite easy because uh the entire mesh is following a neat structure so let's say if I move this here I can uh maybe make it look like a a muscular leg or something so now I have more points to work with so I'm just going to try and utilize all of
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these and then you can say we have a detailed leg here so it's not that I'm trying to achieve a perfection in model here it's just that the point is the more Loops you add it helps you define the mesh better it makes it convenient to work with the mesh you have loops uh adding details is much more easier and then it deforms well so on every level clean topology helps you in many ways now let's say if you had uh instead of subdivision
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surface if you put some uh multi-resolution here and subdivide this a few times let's say three times then I can just go to sculpt mode maybe paint out some of more details here and now here we have plenty of resolution and I can keep on adding more details to it I can go to depth of any details if I want this resolution is quite high and I can subdivide this further if I want but the thing is uh we are losing the performance on this model you can clearly see
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as I scrub the timeline mesh is higher it can support details but it's no longer an optimized model so imagine if we had a entire character in this resolution that would be a disaster to animate and render and this is where normal maps come in so if I just quickly wrap these vertices Mark seam and unwrap this then I can just create a new image texture 4068 by 468 not make this one non- color and put it into normal and then just work in the low resolution here disable all these
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subdivisions and then uh I I can simply bake bake all the details from the sculpt that we did into this texture so if I click on normal map bake from multi-resolution and click bake and this is going to take a few seconds and then now I can bring a normal map here and put it into color and if I try to render this now you'll see we have all the details from the high resolution model but in a normal map which is right here so this is a normal map image which we have
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generated from high resolution model so now this model is low resolution but it's also carrying all the details from high resolution model which is using six subdivisions and now we have a good feedback while we animating this so frame rate is high it's easy to work with easy to modify we can have an entire character in this resolution and it's going to perform quite well so even if I get rid of of this multi-resolution modifier now you'll see we still have all those details
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in normal map hope this gives you an idea about handling resolution and everything as you become more familiar with topology you'll discover it's not meant to complicate your life it's there to simplify it according to me differentiating between good and bad topology boils down to two major factors performance and appearance so the arrangement of these vertices and edges should follow the natural Contour of object that ensures the models maintain realistic and
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good appearance good topology allows addition of intricate details without distorting the overall shape with a fewer well-placed loops and mesh flows you can easily accentuate the forms in the object or body a consistent density of mesh across different parts of the model ensures a uniform level of details controlling a visually pleasing appearance so just because if one part of the body is bigger than the other or one is smaller it doesn't mean it requires less
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mesh or more mesh to capture the right details you need to put enough Loops otherwise things might would fall apart in the close-up shots or something the topology should also facilitate smooth surface enhancing the visual appearance of model quad based topology subdivides well and creates smoother surfaces well organized topology streamlines UV mapping for improved texture application and detailing it's really easy to work with a clean mesh where the topology is
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well organized selecting Loops cutting down the mesh modifying the geometry laying it flat for UV is much easier task and often if topology is cleaner there's a less chance for Distortion and visible stretching in textures the topology should be well optimized for performance whether you're making it for a game or movie it still needs to be under a certain quarter so it's important to
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manage a right balance between how well your model looks and how well it performs in rendering and animation in the later stage minimizing polygons with more than four sides and gones helps in preventing issues with smoothing and deformation so keep your topology based on quarts as much as possible and properly Leed Edge loops and strategic polygon distribution are crucial for animation specifically for characters good topology supports natural movement and deformation
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during animation process and we are going to talk about this in the very next chapter where we are going to modify the loops of the face which kind of resembles the actual human facial structure and muscles topology that aligns with the intended rigging system contributes to better deformation during the character animation for instance it matters what kind of rig you're planning to use
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to decide a topology for your character whether or not it's going to be simple rig or it could be based on muscle system so keeping all those things in mind you will have to make certain decisions about the topology of character additionally editing a mesh is much more straightforward with well- connected Loops in good topology tasks such as creating blend shapes and distributing weight pains for skinning becomes much more manageable when the mesh is clean now every
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object has its own topology tailored for specific purpose likewise in the 3D World topology isn't one size fits for all idea it varies based on different needs and industries in the gaming industry emphasises more on performance models in game often utilize techniques like normal maps and stimulate intricate details allowing game engines to handle extensive scenes in real time additionally level of details lods are used by game engines to preserve the high resolution
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details for objects that appear closer to camera while loading low resolution models or decimating a geometry for distant objects this prevents loading lags and enhances overall gaming frame rates and experience in the film and VFX sector the focus is on achieving highly detailed measures models sometimes are sculpted in millions of polygons to capture the intricate details while these models May undergo ret apologizing for creating a low resolution mesh for animation
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higher resolution versions are used for rendering incorporating displacement maps for realistic details now CAD modeling commonly used in industrial design relies on ner sculls nervs defined by control points and weights create precise and smooth surfaces the these models are particularly suited for product design and Manufacturing nerb surfaces are often created by patching together multiple curves this makes them well suited for creating Automotive surfaces
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product design Etc but they often provide a tool to convert or export models to format suitable for 3D printing and rendering softwares now Within These diverse examples from the animation film and game Industries there's a wide variety of styles and complexities from the cartoon industry to the ad film industry indie game developers motion graphic designers Indie filmmakers experimental filmmakers there's a whole mix of realistic non-realistic stylized and Abstract
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content here rules are often bent to achieve the goals of designers providing a sweet spot for experimentation and creative mixing and this is where I have landed and I have been working exploring a variety of creative possibilities now all this might be building up too much in your head and all these words might be making it seem scarier than it actually is let me give you a few quick examples of how you can control and manipulate topology in a mesh I'll give you
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a few basic examples and later on you can changee it to your heart's content in your own time using these links in description or you can do your own research so this is a simple mesh object uh simple grid just like any other other Primitives you have here so when you're modeling basically you extrude these points edges and faces and this is how you model so this low resolution model is quite easy
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to manage to animate render and going to perform quite well if I need to render this I can apply subdivision surface on this by pressing control 2 and uh this gives you uh a smoother surface shade smooth so this mesh the main mesh underneath it these points are there to control this is what you control to model the smoo surface is what you use to render now when you're working for a game you don't get to use subdivision surface or anything you just need to make sure your model
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on the base level itself have enough topology and whatever is in the model is going to render in the engine as well but when you're working in other animation Industries let's say film TV or something you can use subdivision modeling and this generates all the in between points gives you this smoother surface now subdivision surface takes the average of two points and creates this nice Arc in between which gives you smoother surface now in this case if you need a sharp
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edge you will have to add some more support Loops the closer these Loops are the harder Edge it's going to create like this so that's how you model with the subdivision now if I check the wireframe of this object you'll see in between all these quads we have have multiple of subdivisions going on in between every phase so let's say if this is a simple grid and I apply one subdivision surface
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on this it's going to smooth out all the edges and give me this circular kind of object and if I need to have a sharper ends I can add more Edge Loops the closer these Loops are the harder Edge it's going to produce working with subdivision might would seem a bit tricky but keep in mind it also gives you an advantage so you won't have have to create hundreds of points to make a simple
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smooth shape for instance create one simple insert with it let's add few more Loops here now I can get rid of these four faces and now if I scale these down you'll see we have a perfect circle here now without the subdivision we still have this Jagged hexagon kind of thing going on here but with subdivision you have this perfect circle and this way you can easily achieve smooth and uh
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complex mesh transitions with a control of quite a few points now when you're working with mesh we discussed plenty about this in the introduction series you can subdivide it and this will give you more control over the shape you can press contrl R add more Loops in a particular order if you need any Loops horizontally vertically you can keep on adding more geometry to it now if you need to make a manual cut take a knife tool press K you can cut a gemetry in any angle or any shape
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you want just make sure it's all quad even though I made a cut here it's still 1 2 3 4 Points here and 1 2 3 4 Points here but if I I make one uh random cut let's say like this then I just need to make sure that all the ends meet well so let's click this and connect it here and click this connect it here with knife tool and now we have all quads all these are foursided quads now let's say if you had one a grid like this and in this if you want to make some cut let's say starting
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from here something like this then you can simply make a cut here and while you're trying to make Cuts just make sure you to utilize quarts as much as possible so this I'll have to make a triangle and we are going to convert this into quarts later so one triangle here one triangle here and then one triangle right here another triangle here and gone and triangle and gone and finally one quad
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and now I have kind of similar flow but I need to make few more points here and I need to convert these triangles and andon into into quads so just take a cut tool so in scenarios like this where you have one triangle and one five-sided you can simply create a cut from here to here and then you have four-sided cords here let me apply smooth so that you can see the visualization we have quads
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here and these are nicely subdividing but here triangles are struggling quite well to manage the flow I'm going to create one cut here similar situation now we have a quad here quad here and one board here so do the same thing create a cut and there you go then let's solve this one so mostly whatever Eng gon and triangles we had we have fixed those but despite of that if I select this it's not still quite a full loop which is uh connected through and through
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properly to make this follow a nice and smooth Arc I'll have to make a few more adjustments here once we have the main line which is this one I'll try to form the the lines surrounding it in the similar flow like this right here so that it supports the flow so now you can see kind of like a river or something it's flowing in the similar Direction and now visualization is much more clear what I'm thinking is I can have these Loops to flow in this direction and
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these Loops to flow something like this now to make this happen I'm going to just clean up a bit so if you find it too difficult to visualize where should I connect these triangles and how do I clean it further what you can do is simply select few of these Loops which are harder to visualize with control delete to disolve now you have clear path in front of you you can make few Fresh Cuts right here this is much more cleaner and uh now this should also flow
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like this so instead of these two at right angle what if we connect this here or maybe right here
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and now if I select this Loop you'll see it's going through and through there are few triangles on the Outer Edge which I can solve and now if I apply subdivision surface on this you can see it's clearly flowing in the direction of the sketch now I can bevel this and extrude this and it's going to create a smoother shape and since all of these are in good flow and connected well I can keep on adding more geometry to this
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with loops and everything and it's going to be quite easy for me to detail this out then make sure the distribution is equal now there are few endon and triangles here at the borders all right so now we have this flow in the direction of the initial sketch it's following the similar flow and all the supporting surrounding edges are kind of flowing the same direction so to modify it into a custom flow just make a cut first make sure it's all quads then connect the
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triangles and Eng gon shape the surrounding edges and then you start seeing a slightly more clearer visualization of where you need to be then delete out few of the edges and connect and make more quads now let's start with few more examples let's say if you wanted to have a flow like this so in that case it's going to be quite simpler just make one cut here like this and right here we have this situation if I apply subdivision surface it's going to be
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like this so just connect both of these and there you go your flow is changed right here and then let's say if you wanted to make a flow like this then you can simply make one cut here just make sure it connects with the rest of the edges and it forms the quads there you go the flow is now changed and it's moving like this now if you're making circular formations then for that you don't need to make Cuts you just need to make one insert and there you go
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you have this circular flowing Loop and then you can just scale out few of these you have circular flow right here then you can get rid of this and then make a few more extrusions there you go so now this one is a circular formation now as I mentioned earlier if you have a simple plane and you apply subdivision it becomes all round so if you want some sharp Corners you'll just have to add few supportive Loops like like this and there you have a slightly less sharper
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Square so the sharpness of the corner depends on how many Loops you are adding so right now there are two edges which is forming this radius but if I add one instead and get rid of these two then we have significantly more radius here now let's say if you have a situation where in the one side of the mesh you need less details but along the way you want to add some more details what would
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you do you simp simply need to make a cut like this just remember this and I'll also tell you a shortcut there you go so let's say if you needed less details here and more details here so more Loops here but not in this part without creating any endon what would you do so let's say if we add two Loops here but in this part I don't want any Loops then I can simply move it this way and create one cut like this now I can get rid of these edges and there you go we have one simple
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Square here and and I can make two rectangles here so basically less density here more density here now let's say if I wanted to have more details here so I can use the similar kind of structure for these faces as well you can simply create another cut like this and then you can connect it to the last one so now instead of three you have five or you can also create one for each of these phas now creating a manual cut like this takes some time so instead of
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this you can simply create one inser you can just get rid of these faces and then move it to the side so let's say if we have one more face here and if I wanted some more resolution here I can create one inser get rid of this and move it to side and I can keep on detailing this further so let's say if this was a arm and then I wanted more fingers so I can subdivide like this so there are no triangles or Eng gon here now
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let's say if you had a mesh like this without interrupting the flow of the previous mesh you wanted to reduce the number of Loops here you can simply push two of these and connect these and then you can get rid of these edges there you go so you have less resolution here now more resolution here you can also do the same thing by ripping these apart select two of these press V and rip this apart and now you can simply fill this area and then you can dissolve these two
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edges there you have quad here quad here and these are also quarts or in other situations where you need to collapse the entire row of such vertices you can simply collapse two of these then you can get rid of this entire thing now you got rid of one of the loop here but then you have one triangle here so to solve this just add one right here so this is a quad now and these around the center one are also quad so this kind of makes a diamond shape it's also useful in few
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of the scenarios now there might also be scenarios where you can't really make sense in mesh there are just a few Loops making no sense so instead of fixing these sometimes you can just use a simple grid fill just get rid of this pH and then grid fill if it says you need even number of vertices you can just bevel one of these vertices and then you have GD fill which works for you and then you can fix this one and also a really important thing just keep in mind two triangles make
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one quad so you can use this to manipulate poles poles are are where multiple of these lines meet these can create some weird artifacts just select every alternate elch and dissolve these then you have quad faces here now let's try this one more time you can simply make one cut like this just remember this pattern and then you can connect it through and through and this will subdivide it so
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you have cords and you have more resolution or you can simply insert this delete one side and then move it here now you have more resolution or you can simply add two Loops rip this apart fill this area and now you can get rid of these and there you go so based on the scenario you can use any of the method now let's say if you had a cylindrical object like this on which you have one subdivision
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surface and let's say there are two supportive Loops which makes it a cube kind of object now at the top you have this Eng gon which looks weird in the shading as well and it's really important to close this properly so to avoid this you can simply select this guy get rid of this face and then grid fill and then you can create one more insert like this so this is how you can manage quads manage the density of mesh change the flow and uh use the subdivision to your advantage work
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with the hard angles supportive loops and all that so I hope this clears out a few Basics how you can manipulate mesh flow and topology form quads and maintain the loop flow check the description for few useful links and reference images which will help you out now handling read topology for large scale models with thousands of phases might seem daunting and it is actually but there are tools to simplify this process artists have developed solutions to ease the burden
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for instance the blender add-on B surface allows you to draw lines of topology this automates the generation of mesh based on these lines enables you to create hundreds of links in the matter of seconds and this is much more intuitive instead of driving dragging vertices you can just sketch out few grids and you have your mesh in front of you additionally for highly detailed and complex characters sculpting or 3D scan can be utilized to capture intricate details subsequently the
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model can be theologized we discussed about this in one of the chapter from the previous series from animated content creation series if you're interested just check the chapter number six so to achieve a good topology understanding the Strategic placement of edge Loops is essential they Define the major contour and flow of your object and character contributing to both the appearance and functionality use quads as much as possible working with quals is preferred method
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and it's going to save you a lot of troubles reducing artifacts and Weir deformations when you subdivide it or animate it manage poles carefully especially on curved surfaces it matters where you position them if you can't get rid of poles just put it somewhere where it would create less problems now here are a few practices which might help a plan ahead before you start modeling have a clear idea of the final shape you want to achieve planning helps you create
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an efficient and effective topology keep it simple start with something really low resolution which is easier to manage when the need arrives you can keep on detailing further use quads avoid endon keep a prined visual reference guide in front of you if it helps maintain a good Edge flow plan your Edge Loops to follow the natural flow of object this is crucial for deformation and helps in creating more realistic and predictable models use Edge Loops whenever you're detailing
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instead of creating any abrupt models or cuts which will destroy the topology try to use Loops which connect end to end and close properly this helps in maintaining a clean structure and prevents unnecessary complications for later also possibly producing more quad- based structure and practice with reference images use reference images blueprints to guide your modeling keep some printed guidelines and printouts in front of you and you can also visit few of the models on
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sketch Fab or maybe works by some other artist and see how they plan on their topology try to shuffle between between subdivision mod on and off to ensure a smooth and accurate representation what's going on behind the smooth surface it's also really important but remember practice is key to improving your skills in modeling don't be afraid to experiment and make mistakes so it's not going to be one day's task or you won't be able to memorize all these uh at this stage
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but it will become a second nature of you in fact by the time we are done with this tutorial you'll have much more better command on topology like I mentioned while the definitions do clear out a few things it's beneficial to observe things firsthand begin noticing patterns in your surroundings and examine structures of various objects think about a framework of car chassis what goes underneath
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the shiny surface of the car it might help you understand the loops of the heart surfaces better and when it comes to modeling a human phas could it be the flow of facial structure inspired it so just think about it as you engage in this observation you'll gradually discover various principles guiding your thoughts so next time you model something you won't be approaching it blank slate to illustrate this let's create a simplified head model for our character and
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observe how these Loop Works actually come into play so let's jump onto this video and we are going to create this simple head model this might not be the most detailed head but we are going to practice some of the topology modification in this part so I'll see you guys in the next chapter
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