GreyBeard’s Blender Tutorials
Tutorial No. 2
Modeling with Subsurfs
Welcome to GreyBread’s Blender Tutorials this is my second tutorial and it’s about Modeling the Subsurfs. I’ll also go into the new crease tool that is available in version 2.34 Blender. Well, what are Sunsurfs? Well, subsurfs allow a simple mesh or cage which you create to control a more complex geometry that’s created automatically for you. In Blender, they come in two varieties, simple Subsurfs, which keep the same shape as your cage, but divided up into more phases. This is useful if you wish to send more geometry to the render for instance for doing radiosity calculation or for doing displacement mapping. The Catmull-Clark variety at subdivision surfaces is what most people commonly think of with subdivisions surfaces that you get a nice smooth organic shape inside your cage or guide mesh.
Within the 3D world, Catmull-Clark subdivision surfaces has pretty well replaced the older spline based patch modeling technique used for character models. The spline based approach is still heavily used in the cad cam field.
Now, some general strategies for when you’re using Subsurfs. Keep the control mesh as simple as possible. This is the most common mistake I see you users making is that they have a huge very complex control mesh and it’s not usually ever necessary. Number two; you rarely need subsurf values greater that 2 or 3. The majority of my models are modeled in within the Subsurf value of two and rendered with that same amount of two. Now, you should try to avoid triangles as they can leave artifacts. Sometimes you can have triangles and you won’t really notice it that there and once you become more familiar with modeling you know where you can get away with the triangle, where you can’t. But, it’s best to try to avoid them as much as you can and keep your mesh to just being quads.
Now, that we’ve got this out of the way, we can get on to the modeling part of the tutorial. Here we are with our basic startup screen. I’m just going to erase the default Q. We’re in top view, I’m going to space bar, add a mesh just a plane scale out of it. I’m going to go to the edit mode buttons here and hit subdivide once and key select all the vertices-box-extrude-extrude-extrude. I’m holding down the control key when I’m extruding, so that I can go and even grid amounts. I’m just trying to make a shape here that we can modify and you can see how subdivisions surfaces work.
Okay, I’m going to side front view now with the one key and we’ll do deselect all the vertices-box and we have G-grab those and bring to control key. Deselect all the vertices-box-G grab-deselect all vertices, B-box-grab-deselect all vertices with the A key-B-box-grab. Okay, I’m going to hit the zed you can see the shape that we have.
Now, I’m going to down to the subdivision buttons make sure you’re in edit mode here and I’m going to zoom in on this area and hit control up arrow and here is that area. Now, these are all the subsurf buttons. This turns subsurfing on and off, in this place you can select which type you want the simple, which we’re going to start out with. This is what shows up in your modeling windows, so you’re going to be modeling subdivision one, I’ll change that to two and this is the rendering, which sent to the render you can have a simpler subdivision in your modeling windows. So, that your computer so much and rendered at a higher one, but I’m just going to set that to as well. The optimal button changes the way it’s displayed on your screen, it doesn’t have an affect on the outcome, it’s only how it’s displayed on your screen, we’ll look at that later.
So, I’m going to turn on subsurfs, we’ve got simple subsurfs and we’re doing two subdivisions and now let us go up and look at our mesh. Zed, and you can see when we zoom in this additional phases that were created that are shown in light gray. Now, subdivided it once and then a game, so that’s twice. So, subdividing it twice will give you a lot more phases. There is one, two, three, four, sixteen phases for every single phase you had before. That would be useful if you’re doing a radiosity calculation.
Now, if we switch the subdivision type to Catmull-Clark, you’ll see that we’re going to get a nice smooth curve that’s controlled by this cage that we have here. So, now I am going to zoom back in here and we’re going to change this to Catmull-Clark and then when we view our model again, you can see the nice smooth shape that we have here. Zed--and you can see--now smoothing isn’t turn on yet. So, let’s do that, we’ll select all the vertices and down here, still under the edit buttons if I zoom in, and we go here there is this sets smooth and sets solid of button under linking materials. We’ll do a sets smooth and now, we can look up and you can see by turning off the nice smooth shape that’s underneath.
Now, there are couple ways we can control the amount of curvature. I am going to Zed and tab, I’m going to edge view, I’m going to full screen mode control up arrow and you’ll note that the way curve fits in here. We can adjust the curvature that’s in here. Now, there is two ways to do that; the old way and what use to be the only way is to add more geometry to your models, so we could do a knife at the K key and the do the knife exact and we can cut our model right there and let’s do it again. Knife exact and cut our model right here and if we zoom in, you can see we can get a nice flatted corner here and by moving, we can see what our knife has done here lock to zed. We can see our nice flatted corner that we’ve got in there. That use to be the only way of changing this and then by moving the tab, by moving this, we can change the radius of curvature that we have here. So, now I’m going to be all blocks. G for grab, zed for the zed access, so that we’ll limited this way and then all box and this time we’re moving in the X axis. We’ll press the X, G for grab, and X for the x-axis. We can adjust that roundness of that corner to whatever we want.
Now, the new method that’s in version 2.34, works little differently and I’m going to tab out and I’m going to undo those last few changes by hitting the U key that’s where we were before. What you do is you select your edge that you want to make sharper and hit the SHIFT+e key and you will notice that it gets--the closer you go to the edge, the edge sharpness is shown at the bottom of the screen, it gets greater, so let’s go up to one and we can hit this edge key again. You know isn’t doesn’t look that great yet but one thing you’ll notice is that each vertex, it takes the edge sharpness from this edge and from that edge and from this edge. So, although you’re working with edges it is more vertex base, so to make the entire edge sharp, we should actually go to here, as well. So, like this SHIFT+e and go to one and this edge, as well, SHIFT-E and go to one and this edge. SHIFT+ e and move it up to one and this one, SHIFT e and move it up to one. Now, if we zed tab out, you can see our new geometry here.
Now, there is one thing if we render this edge using SHIFT+e, after this crease with a SHIFT+e. I’m going to set my camera through the easiest way I find to set the camera is if I hit the 5 key on the numeric key pad, which puts you on perspective mode, I then move my view into what I want. When you want to look at have a nice view that edge and then I hit SHIFT + 0, it places the camera there and when I select this edge, I select the camera while I’m still in the camera view and then I’ll do SHIFT up arrow to change my view and I’ll reduce my lens a little, bit so it will fit in the screen. Then I can go into top view game and I’m going to duplicate this light a couple times just what we got some more light on that subject--zero I’ll go to my render buttons and render a picture. I’ll turn OSA on. You’ll notice that this edge still looks so little funny if you want a nice crisp sharp edge using the SHIFT+e method, you’re going to have to increase the rendering subdivision surfaces just little bit.
Now, so we’ll go back into our edit buttons and select our object and I’ll zoom in here again. Now, if we set the rendering buttons remember this a number of subdivision in our model view and this is what’s going to get rendered we’ll set that up to four and I’ll render that picture again. You will see we’ll get a much better crease in here and you’ll notice even on the setting of one, unless you get up to about subsurface five, you’ll still get a bit of fill up there. So, the point that I wanted to bring across was that if you’re using the new wonderful screen, if you’re using the new SHIFT+e method. It’s not only dependent on the appearance of your object when it’s rendered is not only dependent on what you have set with the SHIFT+e. Let’s tab in here and like our SHIFT+e was set to one as you can see edge sharpness was set to one is how would appears when you render is not only dependent on that edge sharpness, but also on what level of subdivision surface. What level of subdivision that you rendered the picture at, so you got to be careful when you’re using the shift-E method that you check both with the modeling method that I used earlier where I just added some more geometry, it basically is going to render how it looks no matter which subdivision value you rendered at. So, that’s a disadvantage of the SHIFT+e. The advantage of the shift-E is of course, you can--don’t have to bother adding more geometry, which in some cases can be difficult and it’s easier to do in most cases.
So, now I’m going to--since we’ve got a basic idea here, I’m going to do a model for you quickly and you can see how you use it well I’m modeling. So, we’ll do file new and erase all. So, we’re going to model upon from a chess set, so I’m going to into front view, CTRL up arrow, to going to full screen and we’ll erase our default Q and we’re going to add a mesh and say a UVsphere. Now, this is 32, now remember I said most people used too much detail here. Let’s set that down to say 8 and we don’t need that many and 8 again. Okay, so now we have the top of our pawn, so I’m going back to our edit mode buttons and let’s set our subdivision surfaces.
Now, we want Catmull, we’re going to set this at two and let’s set at two we’re going to turn on subsurf, make it optimal and we’re also going to hit sets move it here. So, now you noticed the view here with the optimal the way the--I hit the zed key, you can see it is just a different view of the same object if I turn the optimal off now, you can see there’s the one method and here is the other view. I quite off and used the optimal when I’m doing head modeling, I’ll leave it off for now. Okay, turn the zed off going to front view. So, now let’s deselect all of vertices with the A key and box select with the B key, text and we’ll erase some of these vertexes here and now I’m going to box off the game with the B key and extrude in the zed direction. So, I will have the zed so keep it in this zed, I’ll scale adding a little.
Now, I’m going to extrude a game and when I hit the escape key and just scale it and extrude again and that will grab, okay and extrude it again, hit the escape key and scale it again and then we’ll extrude it again, come down scale a little bit wider, going to full screen, extrude again, scale a little bit wider-extrude-escape-scale-extrude-extrude, just go a short distance here I’m going to put a little region in there, extrude-extrude-escape-scale- extrude-escape-scale and this time we’ll going to hit out the control key and scale to zero. Now, if I turn on zed, this is probably the most asked a question I knew, blender users ask, what happened here? What we have is some of the normal are clinging in the wrong directions, so let’s just select all the vertices with the A key. Hit CTRL+n and read calculator normal is outside and we got that and fixed up. Now, I’m going the front view, zed key again, I’m going to deselect all the vertices with A key, B key and I’m going to scale in our little groove that I want.
Now, you’ll notice as I said that we shouldn’t be using triangles. Now, if I go to the zed key and tab, you know I got a bunch of triangles here at the bottom. These triangles are on a flat plane and it doesn’t matter in that case. So, it is not a problem, there won’t be any artifacts from that, since they are on a flat planer part. That’s why I extruded in the bit first and then made my triangles. Now, when I extruded all these vertices and they’re all going to be overlapping there, so if I select all my vertexes and do a W remove doubles, there 7 vertexes to be removed in there right, in there there’s one and then, seven more from our original 8 that we had.
So, now we’ve got our basic pawn shape. Now, we can refine that shape a little bit. First thing I’m going to do is I’ll make the bottom a bit wider, all box and scale a little bit bigger, that looks better and now we can define some of these curves. Now, I’m going to model in, I’m going to model in the top of this part and then here from here on, I’m going to use CTRL + e and we’ll see how the different approaches work. Now, if I hit tab, you may hit all. Make sure I’ve got everything deselected. I’m going to this mode with the zed key, so I don’t see it. If I hit ALT+ b, I can select phase loops and that’s the phase I want. Now, we’re going to model this one, this curve here using the SHIFT+ e value. The SHIFT+ e method, so you SHIFT+ e and adjust our sharpness say to 2.6, little bit--close to point four. And, I’m now going to pick this edge loop around here with ALT+ b, let’s select to that one now, going to front view and we can do SHIFT + e. And now, the bottom one, I’m going to try to duplicate by instead of using SHIFT + e, I’m going to model some more geometries, so I’m going to select all and then knife (exact) and if I click the middle mouse button, little knife in there. Now, I ALT box, I grab this, I’m going to try to make the top and the bottom look equal.
Okay, so when you top edge here, I’ve used the SHIFT + e and on the bottom edge here, I’ve actually modeled in more geometry. In here, I’ve used the SHIFT+ e, as well. Underneath here, I’m going to add some more geometry again and then, we’ll be able to compare later. Now, select all, make sure all of the vertices, I’m going to do a knife (exact) start here, hit enter. There and that’s pretty good. Okay, I like the shape here, so when you SHIFT+ e for--I want to make the crease sharper and I want to make all these creases in here sharp, so I’m going to ALT + b d selects all the other vertices, as well which is nice and I’m going to do SHIFT + e and set the edge sharpness to point six. Now, ALT + b- SHIFT+ e and set the edge sharpness to point seven, ALT + b- SHIFT+ e, 0.8.
Now, I’m going to make this groove a little thinner just like those ones, grab them-zed key, so we’re limited in that, box-grab these ones-zed key, and the bottom groove. I’m going to do a knife again, clicking the mouse button when you’re doing the knife makes it going to nice straight line. And there, now we have a chess piece. Now it’s awfully large for a camera so let’s just scale this down, I am in scaling in edit mode, grab this and put it up there. Now, the same way we arranged our camera before, I’m going to press the 5 key on the numeric keypad to go into and to perspective mode and I’m going to more or less position the camera for a nice view. Press SHIFT + 0 and IT didn’t work this time. There is a bug in this—seven--I don’t what this happens sometimes. Let’s try it again here, SHIFT + 0, there we go.
Now, I have my camera selected, I’m going to increase the lens here that make it a lot more, grab it. I’m moving my camera now and halt the pawn, incase you’re wondering. R-- rotates the camera, okay. Seven puts me in top view again. I’m going to duplicate the light a few times, so we can get--see a little bit better. And I’m going to do a quick render turn on OSA and that’s what our pawn looks like.
Now, I’m going to do one more thing is that I’m now going to increase the render value of the OSA of –the render value for the subdivision surfaces and you’ll notice that the edges that I set with the SHIFT+ e will become sharper, whereas the ones that I modeled in by hand will remain pretty much the same. So now, I’m going to select our pawn again, go back to the added buttons and I’ll zoom in and say I set this to four. These are the render number, 0 and I’m going to go to my render buttons and render a game, it will take a little but longer, because to render this is much more geometry and you’ll notice that these edges in here are sharper now than they were before whereas the once that remodeled by hand, look pretty much the same way that they did before, okay.
Now, if I just to show what is the finished one looks like under optimal with optimal press then tab, just zoom in to full screen. It is just the different representation. Some people like see the surfaces when they’re mapping, okay. So now, a few things to remind you of, try to keep your mesh simple, you’ll noticed I didn’t use 32 as we are going down I could apply, gotten away with four, or six or maybe even four and it would still made a round surface, a nice smooth surface underneath.
Remember if you use the SHIFT+ e that the subdivision that will let you chose will affect your final sharpness of your creases whereas if you model them by hand you won’t. Generally doing the SHIFT+ e is a little faster and add less geometry, the down side is if you export other program, you’ll probably loss that and will have to add edges again and have to add decreases again in your other program and you have to do some test renders to make sure the subdivision level that you render at gives you the adjustments that you want.
Well, it’s my tutorial on Subdivision surfaces. I hope you found that useful. Thanks for watching this tutorial.
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