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CHAPTER 18
Presenting and Documenting 3D Design

Wireframe, hidden line, and shaded views are helpful means of visualizing models during the design process. However, visual styles leave something to be desired when you are communicating designs to your clients. The general public has come to expect designers to be able to produce the kind of realistic computer-generated imagery regularly seen in movies. This chapter will help you learn to do that by teaching you how to create realistic presentation images using the advanced rendering system in the AutoCAD^® program. After you gain client approval, you still need to document your 3D design with relevant 2D plans, elevations, sections, and detail drawings so that your design can be communicated to the building or manufacturing trades. You will learn how to generate these drawings directly from models using AutoCAD 2016’s model documentation features.

In this chapter, you’ll learn to do the following:

Assign materials
Place and adjust lights
Create renderings
Document models with drawings

Assign Materials

Materials describe the way objects interact with light. AutoCAD comes with an extensive library of real-world materials, including numerous types of concrete, metal, glass, brick, paint, leather, carpet, plastic, and so on. In the following steps, you will transfer materials from the Autodesk library to a sample model and then assign them to objects layer by layer.

Exercise 18.1: Apply Materials

Begin by opening the file Ex18.1-start.dwg, which is among the companion files available for download from this book’s web page, www.sybex.com/go/autocad2016essentials. This is a model of this author’s house (see Figure 18.1).

Select the 3D Modeling workspace from the drop-down menu on the Quick Access toolbar.
Select the ribbon’s View tab and click the Materials Browser toggle in the Palettes panel. In the Materials Browser palette that appears, expand the name column so you can read the material names. Click the Category column header to sort the list by category. Scroll down and locate the Fabric category in the Autodesk library. Click the upward-facing arrow icon in the Velvet – Black row to load this material into the document (see Figure 18.2).

Figure 18.2 Loading a material from the Autodesk library into the document

Continue loading materials by single-clicking the materials listed by category in Table 18.1.

Table 18.1 Loading materials from the Autodesk library

Category	Subcategory	Material
Flooring	Stone	Flagstone
Flooring	Stone	Flagstone Light Pink
Flooring	Wood	Natural Maple – Antique
Glass	Glazing	Clear
Masonry	Brick	Uniform Running – Burgundy
Metal	(none)	Chrome Satin 1
Metal	Steel	Stainless – Brushed
Paint	(none)	Black
Plastic	(none)	Laminate Light Brown
Wall Paint	Matte	Cool White
Wall Paint	Matte	Flat – Antique White
Wood	(none)	Beech
Wood	(none)	Birch – Solid Stained Dark No Gloss

Drag the horizontal separator that splits the Materials Browser into two panes down. Figure 18.3’s top pane shows all the materials loaded into the current drawing. Close the Materials Browser.

All drawings have a global material (flat gray) by default.
Select the ribbon’s Visualize tab. Expand the Materials panel and select the Attach By Layer tool. Click the Layer header to sort the list of layers in reverse alphabetical order. Click the Layer header again to sort in alphabetical order. Drag materials from the left side and drop them on the right side according to Table 18.2. Figure 18.4 shows the dialog box with all the necessary materials assigned to specific layers. Click OK to close the Material Attachment Options dialog box.

You can also assign materials by dragging them from the Materials Browser onto specific objects in the drawing canvas.

Figure 18.3 List of materials loaded into the current drawing
Texture maps do not normally appear in the viewport in the Shaded With Edges visual style. Select Realistic using the in-canvas Visual Style Controls menu. Figure 18.5 shows the texture maps in the viewport.

Your model should now resemble Ex18.1-end.dwg.

Table 18.2 Assigning materials to layers

Material	Layer
Global	0
Uniform Running – Burgundy	Brick
Beech	Cabinets
Cool White	Ceiling
Cool White	Ceiling2
Laminate Light Brown	Counter
Global	Defpoints
Birch – Solid Stained Dark No Gloss	Door
Cool White	Downlight
Stainless – Brushed	Equip
Natural Maple – Antique	Floor1
Flagstone	Floor2
Flagstone Light Pink	Floor3
Velvet – Black	Seat-Cushion
Chrome Satin 1	Seat-Frame
Stainless – Brushed	Sink
Birch – Solid Stained Dark No Gloss	Stairs
Beech	Stool
Black	Stove
Clear	Table-Glass
Chrome Satin 1	Table-Legs
Flat – Antique White	Wall
Flat – Antique White	Wall2
Cool White	Window-Frame
Clear	Window-Glazing
Black	Woodstove

Place and Adjust Lights

Without light, nothing would be visible. AutoCAD uses what is called default lighting to illuminate objects in the viewport while you are building 3D models. The default lights are positioned behind the viewer and emit even illumination so that you can always see what is in the viewport. However, default lighting is not realistic and must be turned off as soon as you create artificial or natural light. You will add artificial lights (a series of spotlights mounted in the ceiling) and natural lights simulating the sun and sky light diffused throughout the atmosphere.

Exercise 18.2: Add Artificial Lights

In the real world, artificial lights are electrical lighting fixtures that are one of the hallmarks of the modern world. In AutoCAD, artificial lights include point, spot, and direct sources. Point sources illuminate in all directions, spot sources illuminate in a cone, and direct lights simulate light coming evenly from a particular direction, illuminating everything like the sun.

AutoCAD has two different lighting methods: standard and photometric. Standard lights were used before AutoCAD 2008, and they are still available so that lights in older DWG files will still be compatible in the current version.

However, I strongly urge you to use photometric lights, which are much more realistic. Photometric lights use real-world lighting intensity values (in American or International lighting units), and light coming from photometric light decays with the inverse square of distance, just like light does in the real world.

In the following steps, first you will change lighting units to turn on the photometric lighting system, and then you will add a series of artificial lights to illuminate an architectural interior. To begin, open Ex18.2-start.dwg from this chapter’s companion files.

Switch to the 3D Modeling workspace if it’s not selected already in the Quick Access toolbar.
Select the ribbon’s Visualize tab and expand the Lights panel. Open the Generic Lighting Units menu (used only for the standard lighting method) and select American Lighting Units (or International Lighting Units in metric).
Click the word Top in the ViewCube^® to switch to a floor plan view. Rotate the view clockwise so that North is up. Choose Zoom Extents in the Navigation bar and switch to the Wireframe visual style using the in-canvas control.

AutoCAD for Mac users can change lighting units with the UNITS command.
Select the ribbon’s Home tab and expand the Layers panel. Select the Turn All Layers On tool. Light fixtures (down lights) are visible in the viewport (see Figure 18.6).
Zoom in on the upper-left light by turning the mouse wheel forward. Do the following:
- If you’re a Windows user, select the ribbon’s Visualize tab and, on the Lights panel, open the Create Light menu and select Spot.
- If you’re a Mac user, type LIGHT, press Enter, type S (for Spot), and press Enter.
Select Turn Off The Default Lighting when the Lighting – Viewport Lighting Mode dialog box appears (see Figure 18.7).

Point filters such as .xy, .xz, and .yz allow you to specify the listed coordinate values by clicking in the drawing. Typing the missing coordinate then specifies the 3D coordinates.
The command prompt reads as follows:
```
SPOTLIGHT Specify source location <0,0,0>:
```
Type .xy and press Enter. Click a point visually centered on the light fixture (but do not use center object snap).

Figure 18.6 Viewing light fixture geometry on a floor plan

Figure 18.7 Turning off default lighting when adding the first artificial light source
The command prompt now says (need Z). Type 96 (the ceiling height) and press Enter. The command prompt now reads as follows:
```
SPOTLIGHT Specify target location <0,0,-10>:
```
Type .xy, press Enter, and click the same center point as you did in the previous step. The command prompt now says (need Z).
Type 0 (the floor height) and press Enter. Press Enter again to end the SPOTLIGHT command.
Press the F8 key if Ortho is not already on. Type CO (for Copy) and press Enter. Type L (for Last) and press Enter twice. Click a point near the light fixture, zoom out by turning the mouse wheel backward, move the cursor down to the light fixture in the bottom row, and click in the drawing canvas to create the second spotlight. Press Enter to end the COPY command.
Press the spacebar to repeat the last command, type P (for Previous), and press Enter. Type L (for Last) so that you have a selection of two lights, and press Enter twice to end Select Objects mode. Click the start point under the last spotlight and zoom out. The command prompt reads as follows:
```
COPY Specify second point or [Array]
<use first point as displacement>:
```
Type A (for Array) and press Enter. Type 6 (for the number of items) and press Enter.
Type F (for Fit) and press Enter. Move the cursor under the right-most light fixture (see Figure 18.8), and click to specify the second point of the array. Press Enter to exit the ARRAY command.

Placing lights within block definitions can help keep the source and fixture together.

Figure 18.8 Copying spotlights in a rectangular array
Type V (for View) and press Enter. Double-click Camera1 in the View Manager (see Figure 18.9). Click Apply and OK.

Figure 18.9 Selecting a predefined camera view
Click the Lights panel menu (a small icon in the lower-right corner of the Lights panel) to open the Lights In Model palette (see Figure 18.10). Select the first spotlight in the list, hold Shift, and select the last spotlight in the list to select them all.
Right-click the selected lights in the Light Lister and choose Properties. Select the Lamp Color property and click the icon to the right of the drop-down menu to open the Lamp Color dialog box. Select the Kelvin Colors radio button, type 5000, and press Tab. The resulting color changes (see Figure 18.11). Click OK.

Real-world lamps are typically rated by a color standard and/ or color temperature (measured in degrees Kelvin). The Tool palettes have a set of real-world lamps ready for use.
In the Properties palette, change Lamp Intensity to 15000, Hotspot Angle to 30, and Falloff Angle to 60. Figure 18.12 shows the resulting light glyphs in the drawing canvas. Close the Properties and Lights In Model palettes. Press Esc to deselect all.

Your model should now resemble Ex18.2-end.dwg.

Exercise 18.3: Simulate Natural Light

AutoCAD can simulate the light of the sun and/or the light scattered in the sky by the atmosphere for any location on Earth and for any time of year and time of day. In the following steps, you will configure the model to use a simulated sun and sky with specific time and space coordinates. To begin, open Ex18.3-start.dwg from the Chapter 18 companion files.

Switch to the 3D Modeling workspace if it’s not selected already in the Quick Access toolbar.
Select the ribbon’s Visualize tab if it is not already selected. Click the Sun Status toggle in the Sun & Location panel. The sun is on when the toggle is highlighted in blue. Choose Keep Exposure Settings in the Lighting – Sunlight and Exposure dialog box that appears.

Mac users control Sun Properties in the Properties inspector.
Expand the Sun & Location panel, open the Set Location menu, and select From Map. Choose Yes when asked if you want to use online map data. In the Geographic Location dialog box that appears, zoom into a hypothetical site anywhere in the world you would like. Right-click the map and choose Drop Marker Here. A red pin appears on the map at that location (see Figure 18.13).
Click Next in the Geographic Location dialog box and Select Inches (or Meters for metric) from the Drawing Unit drop-down menu. Select the first coordinate system in the list in your chosen system of units and click Next.

The time zone is selected automatically in the Geographic Location dialog box, but you can adjust it if it is incorrect.

Figure 18.13 Specifying the geographic location of the site
Click anywhere in the drawing canvas to select a reference point for the geolocation data. Press Enter to specify the North direction as up by default. By specifying North on the plan you are establishing the building orientation on the map.
Select the Visualize tab on the ribbon; open the Sky Background menu in the Sun & Location panel and select Sky Background And Illumination. AutoCAD automatically manages the color of the sky and degree of sky illumination based on your chosen time and space coordinates.

images

Your model should now resemble Ex18.3-end.dwg.

Create Renderings

Rendering is the process of converting the geometry, materials, and lighting settings into pixels. Rendering can be a time-consuming process because it typically requires a lot of computation to perform. There are no rendering options in AutoCAD for Mac (just the RENDER command), and the resulting rendering quality isn’t as realistic as that available in AutoCAD for Windows, where you have many advanced options. AutoCAD 2016 has a new rendering engine called Rapid RT that produces high-quality imagery with fewer user-configurable parameters.

Exercise 18.4: Make More Realistic Renderings in the Cloud

In the following steps, you will use AutoCAD 2016’s advanced render settings for Windows to progressively create more realistic renderings. To begin, open Ex18.4-start.dwg from this chapter’s companion files. Preview renderings are free on Autodesk’s cloud-based A360 service. Cloud credits can be purchased to render high-resolution images up to 4000×4000 pixels on Autodesk’s network of servers. Using A360 to render final images can be much quicker than rendering locally, even considering time spent uploading the drawing and downloading the final rendering, because the job is rendered on a large network of render servers that far exceed the computational power of any one personal computer. Another practical benefit of rendering in the cloud is that your local computer remains usable for other tasks while rendering.

Switch to the 3D Modeling workspace if it’s not selected already in the Quick Access toolbar.
Select the ribbon’s Visualize tab. Click the arrow in the lower right corner of the Render panel or type RPREF and press Enter to open the Render Presets Manager. You will begin by making a preview render in the cloud. Select Low from the Current Preset menu (see Figure 18.14).

By default, the Low preset renders one level, which allows you to check that the lighting is acceptable before investing more rendering time.

Figure 18.14 Render Presets Manager
Save your work as Ex18.4.dwg. Click the Render In Cloud button in the A360 panel. Select Camera1 as the Model View in the A360 dialog box (see Figure 18.15) and click the Start Rendering button.

If you chose to render locally, you will be prompted to install the Medium Images Library (700 MB) of texture maps. For the purposes of this book, you do not need to render locally.

Figure 18.15 Selecting a model view for a preview render in the cloud
Click the Render Gallery button to launch your default browser and go to Autodesk’s A360 site. After a few moments, your preview rendering will appear as a thumbnail (see Figure 18.16), rendered by Autodesk’s network of servers.

Depending on A360's rendering load, your rendering job might go in a queue. If so, the A360 site gives notification of the estimated wait time.

Figure 18.16 Rendering in Autodesk A360
Click the menu that appears on the rendered thumbnail image and choose Adjust Exposure. Change Exposure Value to 8.88 and Shadows to 0.5 and click Apply (see Figure 18.17). Your thumbnail image is automatically re-rendered will appear shortly.

Figure 18.17 Adjusting exposure of rendering online
After the new thumbnail image appears, open the thumbnail menu and choose Re-render With New Settings to open the Render Settings dialog box in the browser. Choose Field for Environment, set Render Quality to Final, and choose Large as the Image Size. Exposure will say Customized because of what you did in the previous step; no more changes are needed. You can optionally check to be emailed when the job is complete (see Figure 18.18). Click Start Rendering; you will see a progress bar as the rendering is processed on A360.

Figure 18.19 shows the final rendering. This particular image took about 10 minutes to complete.

Document Models with Drawings

AutoCAD has a set of model documentation features that allow you to generate 2D plans, elevations, sections, and/or details directly from solid and surface models. These features are not available in AutoCAD LT^®.

Exercise 18.5: Document Models

In the following steps, you will open a 3D model of a gear and project multiple 2D drawings from it. To begin, open Ex18.5-start.dwg from the companion files (see Figure 18.20).

images

Select the 3D Modeling workspace from the drop-down menu on the Quick Access toolbar. Select the ribbon’s Home tab.

Figure 18.20 Gear 3D model
Select the Base tool in the View panel on the right edge of the ribbon and choose From Model Space in the drop-down menu. The command line reads as follows:
```
VIEWBASE Select objects or [Entire model] <Entire model>:
```
Select the gear object and press Enter.
The command line reads as follows:
```
VIEWBASE Enter new or existing layout name to make current or [?] <24x36>:
```
In this case, there is already a layout called 24×36, so press Enter to accept this default layout. AutoCAD switches to the 24×36 layout, and you are prompted to specify a location for the base drawing. Click an arbitrary point in the lower-left corner of the layout (see Figure 18.21).

You can also link Autodesk Inventor^® base models into AutoCAD in order to generate dimensioned shop drawings.
The drawing is too small, so you will adjust its scale. The command line reads as follows:
```
VIEWBASE Select option [select Orientation Hidden lines Scale Visibility
Move exit] <exit>:
```
Select Scale from the dynamic prompt menu. Type 1 and press Enter again. It just so happens that several views of the gear fit on the page with the gear at actual size.

Figure 18.21 Locating the base drawing on a layout
Press Enter to accept the default Exit option, and you will see that the VIEWBASE command continues.
Click a point above the base plan drawing to locate a second projected view of the top of the gear.
Click a third point at a 45-degree angle with respect to the base plan to locate an isometric projection and press Enter to end the command. The drawings display in wireframe view showing hidden lines with a dashed linetype (see Figure 18.22).
The isometric view is a bit large. Select it, and you will see a special border appear around the view object. On the temporary Drawing View tab that appears, click Edit View. Change the scale to 1:2 in the drop-down in the Appearance panel. Open the Hidden Lines drop-down and select Shaded With Visible Lines (see Figure 18.23). Click OK in the Edit panel.
Select the original base view of the gear object in the lower-left corner of the layout. Click the Section tool in the Create View panel.

Figure 18.22 Locating projected views of the base drawing on the layout

Figure 18.23 Changing a view’s display properties
Toggle on Ortho in the status bar. Click points A and B shown in Figure 18.24 to draw a section cut line and press Enter. Click point C to locate the section view and press Enter to end the VIEWSECTION command.

You can move the view objects to better arrange them on the layout.
Select the original base view of the gear object in the lower-left corner of the layout yet again. Open the Detail drop-down on the Create View panel and select Rectangular. Toggle off object snap in the status bar. Click points A and B shown in Figure 18.25 to draw the detail area and press Enter. Click point C to locate the detail view and press Enter to end the VIEWDETAIL command.

Figure 18.24 Creating a section of the base view

Figure 18.25 Creating a detail of the base view
Toggle on object snap in the status bar. Switch to the Annotate tab on the ribbon and select the Linear tool in the Dimension panel. Dimension the features shown in Figure 18.26. These dimensions are associated with the section and detail views, which in turn are associated with the base view, which is in turn associated with the model. If you were to change the gear geometry in model space, views and dimensions would automatically update on the layout.