Chapter 5: Advanced Techniques

In this chapter, we will try to use our abilities from the first three sessions (2D) and combine them with the knowledge of ACAD 3D, that we have learned so far. We will also add some new techniques, in order to model, texture and render a Doric Column in AutoCAD 3D.

Start with a fresh scene and download a reference file where you can see a cut through a Doric Column from the top. As we have discussed in Chapter 2, please attach the image file in the Top View, in order to have a reference. Don't worry so much about scale this time, we won't be that exact. When you have attached the image, do a redrawing of the left section. Put it on a seperate layer and do a nice little redrawing as we have learned in the last chapters. Make sure to use the Polyline and to draw the whole section in one continuous line.

When you are finished, switch to 3D view and turn off the original drawing, so you are just left with a 3D view of your section drawing of a Doric Column. The next step, should be to raise the section into a 3D object. We can do that with the Extrudieren/Extrude command from the 3D-Werkzeuge tools. Select your drawing, the press the Extrudieren/Extrude button and raise the column to something like its own diameter. You don't have to be exact here, just eyeball it. If you change your view from 2D-Drahtkörper to Konzeptuell in the upper left corner, you have a better view on your first barrel of the column. In the next step, we want to copy our barrel 8 times, so we create a proper column of 9 barrels. We do not try to create a replica or reconstruction of anything, this is just an exercise for you to get to know the tools and commands of ACAD.

For this, we simply use the command we already know: Kopieren/Copy. You'll find it under the Start tools. Select your object, select the tool and then copy barrels on top of each other. This is best be done in the sideview so you can make sure the barrels are on top of each other. Again, don't be too exact, as ancient columns also never were. When you are done copying, change back to 3D mode, to check your work. It might be, that you have to correct some of the copies from the other side. In the end, your column should look something like the screenshot on the side. Notice, that the column has the color of your layer it was created on. We will change that later. The only two things missing here are the Echinus and the Abacus.

The Echinus will be modelled with the Rotieren/Revolve command from the 3D-Werkzeuge tools. Before we can do that however, we need to create a half sideview of what we want to rotate. To have a visual aid, we already want to draw that shape on top of our column. Usually, it is not possible to draw in a side or front view, as ACAD only allows for drawing in the Top View. To change that is easy however. When you have decided for a view, so let's say the Front View, go into the Visualisieren/Visualise tools and find the Koordinaten/Coordinates tab. Inside you should find a button called Welt with a little world and a gizmo icon besides it. If you open the drop-down menu and change the selection to your choosen view (so in my case it would be Vorne/Front), then you should see that the Front View becomes the Top View and you are able to draw. So, draw a little shape with a polyline like in screenshot on the side. Make sure the central line is more or less in the center of your column and that the line is a closed object.

You can change back the drawing plane by changing the drop-down to Welt/World again. Your Top View should become your Front View again, and you have created a shape on top of your column. By default, the drawing is exactly on the plane you have drawn on, so you need to move the shape in one direction, so it sits exactly in the center of the top column with its innermost side. Now, select the shape and find the Rotieren/Revolve button in the 3D-Werkzeuge tools. ACAD now wants to know around which axis we want to rotate the shape. Of course, we want to rotate the shape around its base line in the center of the column. So with Snapping turned on, we select the lower point and the upper point of the central base line. We already can see now how the object is rotated. Instead of painfully searching for the right position to click, we simply hit the Enter button to tell ACAD, that we want a full circle rotation.

We now only need the Abacus which we will simply create by the already known tool of Quader from Chapter 4. You can again place it directly on top of the Echinus while hovering above it until the top face of the Echinus turns blue. Don't worry about the size at the moment, just create a cube. After you have done that, you can adjust the size with the little blue arrows when the cube is selected. Make it slightly bigger than the Echinus and not very high, as you can see in the screenshot on the side. We are now finished with the modelling part of this tutorial. The next step is to give the column a bit of color. We won't get too much into the next two parts of texturing and rendering, but enough to create a nice little outcome of this exercise and to get you started.

Texturing

To give our column a better appearance, we need to texture it. What this basically means is that we will wrap it with a material, in order to give it another look or to simulate the properties of a material. In order to do so, you need to have the tool group Visualisieren/Visualize activated in the top row. In it, you'll find a material browser called Materialien-Browser where you can find preinstalled materials from ACAD. We will stick with these for this exercise, but note, that you can of course add own materials to the library.

When you open up the Materialien-Browser you'll see a list of materials. You can navigate to a certain type of material through the list on the left or simply enter a keyword in the search bar on top. If you decide for a marble texture for example, ACAD has a whole folder for that. To apply a material to an object, you simply drag & drop it from the material browser to the object. If you cannot see any difference, make sure, that the option Materialien/Texturen is turned on not off. You can give different objects different materials. For the top, I decided to go with a dark marble and for the rest with Travertine.

Rendering

You already can see some result in the drawing space, but to get a better image, we will need to render a result. Rendering basically means that the software is calculating lights, shadows, reflections and everything else in order to produce a realistic image. We can close the Materialien-Browser now and have a look at the other tools of the Visualisieren/Visualize menu. Without changing anything, we can have a look at the current result of a rendering process and then refine some things in order to learn something. To give it a try, simply press the teapot symbol in the middle of the menu. Below it, it is written Rendergröße, but we will take care of this later. A new window should appear and it also shouldn't take so long to produce an output. As you can see, the result is not that bad, but we can improve it. First, we need a proper light source and the sun is always a proper light source. To activate it, press the sun symbol Sonnenstand in the menu. A small extra window should appear where you can enable the Umgebung/Environment and change the Bildbasierte Beleuchtung to Platz. Give the render button another try, the result should have been improved.

We can improve the image further however. First, create a very big, but very low cube, that we can use as a floor for the scene. It should be big enough, so that it fills the whole view that you will be rendering, but it should not be very high, as this would cascade our column. Try to find a material for that floor and assign it to it. I decided for Ahorn - Palisandereffekt, but basically it doesn't matter. Try some different materials and check the outcome by pressing the render button. With a floor, we get reflection and our column should look even better (if that is possible).

The last thing we want to change to get a better image is the resolution and quality of the render. To change the resolution, click on the little arrow below the teapot for rendering. There you can choose a higher resolution for the image, like 1920x1080 pixels. On the right side, you can also increase the render quality from Mittel to Hoch. Rendering time will increase, but it should be fine. The final result is the final result of this exercise. Congratulations!

This page was last edited on 2024-12-01 11:26

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This page was last edited on 2024-12-01 11:26

Sebastian Hageneuer
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