So up until this point in the course, you've been working mainly with what I call abstract forms or constructions and I hope you found these to be both enjoyable and also a good introduction to the 3D modeling environment. In this lesson we're going to specifically focus our attention on modeling objects from life, things we find in our immediate environment. And I think this is an excellent way to start to introduce more complex modeling tools through a sequence of things that will introduce more complex forms that we're going to be modeling from. And hopefully by the end of this you would start to see the world a little bit differently, you're going to start to see it through the eyes of a modeler. It should be a fascinating journey as each model is like a little puzzle, it's like a little problem unto itself that we need to unpack. In this lecture, I want to introduce one of the fundamental aspects or concepts to this process of surface modeling and rhino. And that's something I call profile modeling now, to a certain extent, in the last assignment, the 3D tile assignment. You were really already doing something that I would call profile modeling when you were using the extrusion tool. Now, what really happens when we use the extrusion tool? Well we take a curve or line or shape and we pull it through space along an axis. It just so happens that that axis is preset because it depends on our orientation to the seaplane. So that axis with the extrusion tool is always going to be the Z axis and we can pull that in a positive or negative direction. The profile that we are pulling through space is that shape. So that that 2 D shape that we made. That's what I call our profile. And the axis that we were pulling it along is our path. And what we're going to look at is that that path can be a lot of different things, it doesn't have to be the z- axis. That there's a lot of different ways that we can do this. So section, now section is a fundamental concept to understanding something about profile modeling. And a section is produced when I take an object and I slice through it along a plane. And what I'm doing is I'm revealing the inside of that object. I'm also revealing its sort of outermost edge. An apple of course, is an ideal example because I can literally take an apple and I can chop it in half and I literally see it section. So what we're going to have to do in profile modeling is we have to essentially imagine this section. We have to use our imaginations to understand cutting through objects in order to find that section that we're going to develop our models from. And so this outer edge, this outer surface, this line that defines the outer surface of the apple is what I would call our profile in this case. Now, because this apple is somewhat symmetrical and we're going to see this in a way lot of forms that will look look at that, it's the same on both sides around an axis. I actually only need half of the profile if I was going to make a model from this and that brings us to our first profile modeling specific tool and that's called revolve. So in revolve, we take our profile and we rotate it around an axis, and in that action we create our surface and now we can do this all. If we do it all the way around 360°, we can create one sort of continuous. And oftentimes, if we have a closed if we have a closed shape it creates a closed surface form, I don't have to rotate it all the way around, it could only rotate it part way and that's going to be up to us when we create it. Now, revolve is one of the most common actions that we find. And what I've done and I have three examples here and I just found some stuff in my office that I could use to model. And if you actually right now, if you looked around in your immediate environment, you could probably pick out half a dozen things. That one could model just through using the revolve. So a cup, a bowl, it could be a chair leg, it could be a handle on something. Revolve is one of the most common used forms. So the first step in this process and these, I did just as a kind of sketch, I wasn't measuring anything, I was just kind of looking at the object and kind of sketching it out in rhino. And the first step of this process is what I call blocking out. So I start with the axis, what's the axis I'm going to revolve around because I only need to draw right one half of the profile because I'm just going to rotate that around the axis. So I get my access drawn, this is all being drawn on the same sea plane. And I start to block out my different forms. I block out the top of the cup, I block out the bottom, I know the bottom is offset up inside a little bit and then I have an angle for the side of it. And then I have that little lip at the top which I did a sort of circle. So I have all of my elements and I usually block these out, I draw them very long. I'm going to do a whole demo or lecture on blocking out. Because it's a really essential part of 3D modeling, but after I'm done with that, I trim all the lines that I don't need out. And then I take those lines that I want to use to produce the 3D form and I rotate them using the revolve tool around that axis. And I could do it in 180 degrees or I could do it in 360 degrees to create a complete cup. And this is a little lamp I had in my office. So essentially went through the same process of sketching these things out. If you notice that element in the trimmed lines that I can actually have elements that are pulled away from the axis. And so the further away from the axes, they are, the bigger I would get this sort of opening in the top or the open in the bottom. So things don't have to be up against the axis if they are, they would become closed. Now, this third example, this coffee mug gets a little bit more complicated. One of the complications with it, it's a solid form. So it's something that has thickness. So those first two didn't have thickness, I was just doing them as simple one could say 2D surfaces. And so this one, I'm using an offset line, has a couple more arcs and shapes to it, it's a bit more complicated to draw. And it actually creates a solid 3D form that if I wanted to, I could actually produce something like a 3D print from it. Now, you might notice something else also in this and that's the handle. The handle is constructed from a different type of operation, so that's constructed separately from the revolve and that uses a couple of different processes. And the one I want to talk about next is called sweep. And sweep allows us to take a profile like we did with revolve, but instead of just rotating it around an axis, it allows us to sweep it along a a path or a rail of our making. There's also another element here. If you look very closely at the handle, if you see where it meets that revolved surface, it has something called the fill it, we'll get to fill it's later in the lesson, but that creates a transition between those different surfaces. So a sweep allows us to take a profile and the profile I'm talking about just so it's clear I can point it out, it's this little one right here. Okay, and so that was produced by making a rectangle fileting the corner and then sort of squeezing the middle of it a little bit because that handle had a little dip in it. Where you could, when you grab it your fingers hold onto it and its edges were a little soft. All I did was take that profile and I swept it along this outer curve. I didn't actually need this inside curve at all, I only needed one. And so it takes that profile and it sweeps it around and that's what creates this surface. And I did it in a way that it overlaps, you can see it overlaps that surface because I could later trim it and we're going to be able to trim surfaces with surfaces, and curves with surfaces, and surfaces with curves. We're going to get into all of that, which is very a really interesting part of surface modeling. So a sweep, I can take this profile, I can sweep it around a rail. That rail in a sense, is its own profile. It can take any shape I want to give it also with sweep, there's other things I can do with it, I could have a different ending profile. And in this case I'm showing an open curve with the handle that was a closed curve. So I can do it with opener or closed curves. Something else that's really interesting, which makes it an incredibly versatile tool. Sweep is that I can put different profiles along the rail and that tool is going to translate, it's going to create a translation between these different profiles along that rail. So it's one of the tools we're probably going to use most in creating different forms. Now there's something called sweep 2. Sweep 2 allows us to use all of the things I just showed in sweep 1 allows us to create different profiles along its length, but it also allows us to use two different types of rails. Now, this example is showing those rail in the same plane, they don't have to be, they could be completely out of plane and this is still going to work. Sweep 2 is still going to work and we can experiment a little bit these, you'll notice my sections, my profiles are sort of self similar, right? It's like one is created from a re-scaling of the other one and that is going to create a clean surface, but I don't necessarily have to do that. I can have, sweeps going to translate between whatever I give it. So I could move from a very rectilinear curve to something very, very smooth and it's going to translate along its length and we're going to show a bunch of that in the demo tutorials. Now, just back just to to close with a sort of real world example, where would I use sweep? Again I want you to run through the exercise of looking in your immediate environment and here's a little hint is that oftentimes we when we model something. And this is going to happen with revolve or would sweep, we're only using those tools as a part within a bigger process. So an an object might be made up of multiple operations or multiple processes. So if we think of something that we might use sweep for, you're looking at a computer screen or iPad screen or something like that right now or even a cell phone. The surrounding frame of that could be produced from a sweep, the body of it, the rest of the body, the screen, it might be produced from a planer surface operation. And then I might use bullying operations or other extrusions to produce other things like buttons and different things on it. So again, sweep might be only used in part in terms of a whole assembly and we're going to get into. In the next part of this lesson, we're going to get into issues of assembly and starting to look at objects as assemblies of things and of different profiles and so that will be a pretty interesting component of this. Looking at object modeling.
