Rendering in 3D - Creating a Scene

Working with lists of materials Materials are saved in a file with the extension .mli (materials library). The default materials library is render.mli. The left side of the Materials Library dialog box represents materials in the current drawing. The right side of the dialog box represents the entire list of materials provided by AutoCAD. In the Current Drawing section, you can: ✦ Click Save As to save the list of materials in the current drawing in an .mli file. ✦ Click Purge to delete all the materials in the list from the drawing. In the Current Library section, you can: ✦ Click Save to save changes to the entire library list in the MLI file in the current folder. ✦ Click Save As to save the entire current library list in a new MLI file in any location. ✦ Click Open to open a different library list and use its materials. Importing and previewing materials To add existing materials to your drawing, follow these steps: 1. Choose a material from the Current Library list on the right side of the dialog box. 2. Click Import

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882 Part IV ✦ Drawing in Three Dimensions To create a scene, choose Scenes from the Render toolbar to open the Scenes dialog box, shown in Figure 25-16.This dialog box lists your scenes and enables you to create, modify, and delete scenes. Figure 25-16: The Scenes dialog box To create a new scene, follow these steps: 1. Click New to open the New Scene dialog box, shown in Figure 25-17. The New Scene dialog box lists all the saved views and all the lights you have created. 2. Type a name in the Scene Name text box, no more than eight characters long. 3. Choose a view. You can choose only one. 4. Choose the lights you want. Press Ctrl to choose more than one light. Press Shift to choose a range of lights. You can also choose *ALL* to quickly choose all the lights for the scene. 5. Click OK. Figure 25-17: The New Scene dialog box 30 539922 Ch25.qxd 5/2/03 9:41 AM Page 882 883Chapter 25 ✦ Rendering in 3D Your scene is now listed in the Scenes dialog box. Click OK again to return to your drawing. When you render the drawing, you can choose this scene from the Render dialog box. The drawing used in the following Step-by-Step exercise on creating a scene, ab25-2.dwg, is in the Results folder of the AutoCAD 2004 Bible CD-ROM. Step-by-Step: Creating a Scene 1. If you have ab25-02.dwg open, use it. Otherwise, open it from your AutoCAD Bible folder or the Results folder of the CD-ROM. 2. Save the file as ab25-03.dwg in your AutoCAD Bible folder. If the Render toolbar is not open, right-click any toolbar and choose Render. 3. Choose Scenes from the Render toolbar. Click New in the Scenes dialog box to open the New Scene dialog box. 4. Type morning in the Scene Name text box. 5. Choose RENDER1 from the Views list. 6. Choose D1 and P1 from the Lights list, pressing the Ctrl key while you select the second light. 7. Click OK twice to return to the drawing. 8. Save the drawing. If you are continuing on to the next Step-by-Step exercise, keep it open. Working with Materials Working with materials involves two steps — adding them to the drawing and attaching them to objects. Designing appropriate materials is an important part of the rendering process and greatly affects the results. Materials interact with lights. For example, shiny materials reflect light differently than dull materials because shiny materials create highlights. The object’s color affects how light appears on it as well. Adding materials AutoCAD comes with a large selection of materials. You can modify these to create your own materials. To add materials to the drawing, choose Materials Library from the Render toolbar to open the Materials Library dialog box, shown in Figure 25-18. On the CD-ROM 30 539922 Ch25.qxd 5/2/03 9:41 AM Page 883 884 Part IV ✦ Drawing in Three Dimensions Figure 25-18: The Materials Library dialog box Working with lists of materials Materials are saved in a file with the extension .mli (materials library). The default materials library is render.mli. The left side of the Materials Library dialog box represents materials in the current drawing. The right side of the dialog box repre- sents the entire list of materials provided by AutoCAD. In the Current Drawing section, you can: ✦ Click Save As to save the list of materials in the current drawing in an .mli file. ✦ Click Purge to delete all the materials in the list from the drawing. In the Current Library section, you can: ✦ Click Save to save changes to the entire library list in the MLI file in the current folder. ✦ Click Save As to save the entire current library list in a new MLI file in any location. ✦ Click Open to open a different library list and use its materials. Importing and previewing materials To add existing materials to your drawing, follow these steps: 1. Choose a material from the Current Library list on the right side of the dialog box. 2. Click Import. 30 539922 Ch25.qxd 5/2/03 9:41 AM Page 884 885Chapter 25 ✦ Rendering in 3D 3. Choose the material from the Current Drawing list. 4. From the Preview drop-down list, choose the preview type of either Cube or Sphere, based on whether the object you want to use the material for is flat or curved. 5. Click Preview to see a sample of the material. 6. Repeat Steps 1 through 5 until you have all the materials you want. 7. Click OK. If you don’t find the exact material you want, import the closest one you can find. You can then create a new material based on that material. The next section explains how to edit existing materials. You can choose a range of materials by holding down Shift and clicking the first and last materials in the range. You can choose any nonconsecutive materials by holding down Ctrl and clicking the materials you want. If you don’t like a material that you have imported, highlight it and click Delete. Use the Export option to save materials you have created in the drawing to the materials library file. When you click OK to close the Materials Library dialog box, AutoCAD asks you if you want to save the changes you have made to the materials library file. Saving the changes updates the file. The drawing used in the following Step-by-Step exercise on importing materials, ab25-3.dwg, is in the Results folder of the AutoCAD 2004 Bible CD-ROM. Step-by-Step: Importing Materials 1. If you have ab25-03.dwg open from the previous exercise, use it. Otherwise, open it from your AutoCAD Bible folder (if you did the exercise) or the Results folder of the CD-ROM. 2. Save the file as ab25-04.dwg in your AutoCAD Bible folder. If the Render toolbar is not open, right-click any toolbar and choose Render. 3. Choose Materials Library from the Render toolbar. Hold down Ctrl, and scroll as necessary to choose Beige Plastic, Green Glass, Light Wood Tile, Pink Marble, Stitched Pattern, White Matte, Wood Med. Ash, Wood White Ash, and Yellow Plastic. Click Import. 4. From the left list, choose Pink Marble. Choose Cube from the Preview drop- down list and click Preview to see the result. Do the same with Stitched Pattern. 5. Preview Green Glass with the Sphere. 6. Click OK. Save your drawing. If you are continuing to the next Step-by-Step exercise, keep the drawing open. On the CD-ROM Tip 30 539922 Ch25.qxd 5/2/03 9:41 AM Page 885 886 Part IV ✦ Drawing in Three Dimensions Creating your own materials After you import materials from the materials library, you can modify them to create your own materials. Choose Materials from the Render toolbar to open the Materials dialog box, shown in Figure 25-19. Notice that you can click Materials Library in this dialog box to open the Materials Library dialog box. You can therefore use the Materials dialog box to manage the entire process of importing, creating, and attaching materials. You can preview imported materials in this dialog box as well. Figure 25-19: The Materials dialog box When you create a new material, you have three choices: ✦ You can modify an existing material. ✦ You can duplicate an existing material and then make modifications to the copy, leaving the original material intact. ✦ You can start from scratch and create an entirely new material. The dialog box that AutoCAD opens when you choose one of the preceding options depends on what you choose from the drop-down list below the New button. You have four choices: standard, marble, granite, and wood. ✦ Standard creates a standard material. ✦ Marble creates a material that mimics marble. In this dialog box you specify turbulence and sharpness of the veins as well as the scale of the veins to the entire object of marble. 30 539922 Ch25.qxd 5/2/03 9:41 AM Page 886 887Chapter 25 ✦ Rendering in 3D ✦ Granite creates a material that mimics granite. In this dialog box you can spec- ify up to four colors and their sharpness (distinctness) as well as the scale of the texture relative to the entire granite object. ✦ Wood creates a material that mimics wood. In this dialog box you specify the light/dark ratio of the grain, the ring density and width, and the scale of the rings relative to the entire wood object. When you choose a method of creating a new material, whether by modifying, duplicating, or creating from scratch, AutoCAD opens the dialog box appropriate to the material you have chosen. Figure 25-20 shows the New Standard Material dialog box. Figure 25-20: The New Standard Material dialog box Unless you are modifying an existing material, you first give the material a name in the Material Name text box. You use this dialog box by choosing the attributes listed on the left side one by one and then specifying the values for each attribute from the choices on the right. Color/Pattern The color is the basic color of the object. The reflection of light off the object (called diffuse reflection) is determined by this color. You set the color in the Color section of the dialog box, using one of four methods: ✦ Choose By ACI (AutoCAD Color Index). This option enables you to set the color to the color of the object in the drawing. You must uncheck this to choose one of the three other methods. 30 539922 Ch25.qxd 5/2/03 9:41 AM Page 887 888 Part IV ✦ Drawing in Three Dimensions ✦ Choose RGB from the Color System drop-down list to specify the color using the red-green-blue system. These are the three primary light colors. For each color you can type in a value from 0 to 1 or use the slider bars. When all three are set to 1, you get white light. ✦ Choose HLS from the Color System drop-down list to specify the color using the hue, lightness, and saturation system. Hue is the color; lightness — or brightness — is the amount of white the color contains; saturation is the amount of black the color contains. ✦ Click the color swatch to open the Windows Color dialog box, letting you specify a color using either the RGB or the HLS system. In addition to setting the color, you set the value. The value affects the surface finish and interacts with the reflection value. For example, AutoCAD recommends using a color value of 0.7 and a reflection value of 0.3 for a dull finish and reversing the values for a shiny finish. You can type a value or use the slider bar. If you choose a bitmap (raster) file, the color becomes a pattern. See the sidebar on “Mapping” for more information. Ambient The Ambient color and value affect the color reflected by ambient light. Remember that you set the amount of ambient light when you created lights. You can click the Lock check box in the Color section of the dialog box to lock the ambient and reflection colors to the main color. (You cannot use Lock if you checked By ACI as the color.) Reflection The reflection setting affects highlights created by light that shines on the object. To create a shiny object, you can use a reflection value of 0.7 with a color value of 0.3. Shiny objects often create a white highlight — for this effect, set the color to white by setting red, green, and blue to 1. You can also choose a bitmap file to cre- ate a reflection map. See the sidebar on “Mapping” for more information. Roughness Roughness has no color setting — you only set a value. A rough surface produces smaller highlights. Use a lower value to create smaller highlights. If you chose a zero value for reflection, the roughness setting is not used. Transparency The transparency setting enables you to create transparent or translucent materials. You set the value from 0 to 1. Higher values mean greater transparency. Using trans- parency increases rendering time. You can choose a bitmap to create an opacity map. See the sidebar on “Mapping” for more information. 30 539922 Ch25.qxd 5/2/03 9:41 AM Page 888 889Chapter 25 ✦ Rendering in 3D Mapping AutoCAD lets you project a 2D image onto the surface of a 3D object. This is called map- ping. You must use the Photo Real or Photo Raytrace rendering types to render with map- pings. The 2D images are bitmap (raster) files that can be in several file formats, such as TGA, BMP, TIF, and JPEG. AutoCAD provides a large number of TGA files. To locate them, choose Tools ➪ Options and click the Files tab. Double-click Texture Maps Search Path. (You need to do a full or custom installation of AutoCAD to get all the texture maps.) You can actually place up to four bitmaps onto an object. When you create a material, you can add bitmaps to the Color/Pattern, Reflection, Transparency, and Bump Map characteristics of a material. Four kinds of maps correspond to the four characteristics: ✦ Texture maps place a pattern of colors onto the object. When you include a bitmap in the Color/Pattern definition, you turn a plain color into a pattern. ✦ Reflection maps place a scene on the surface of a reflective object, in the same way that you can see yourself reflected in a pool of water. Add a bitmap to the Reflection definition. ✦ Opacity maps mimic areas of opacity and transparency. Add a bitmap to the Transparency definition. ✦ Bump maps create the effect of varying heights. Choose Bump Maps and choose a bitmap file. AutoCAD comes with a number of materials that include maps. In the Materials Library dia- log box, check out the Bumpywhite stone and Checker textures, for example. As their names make clear, the first material is a bump map and the second a texture map. Import and preview them to see how they look. Using these materials saves you the task of speci- fying a bitmap file. Bitmap Blend determines how much the bitmap is used. The values range from zero (0) to 1. For example, a 1.0 value for a bump map gives you the full value of the bumps. A lower value creates lower bumps. Choose Adjust Bitmap to open the Adjust Material Bitmap Placement dialog box. Here you set the offset of the origin of the bitmap and the scale. The scale is the number of times the bitmap fits onto the object. If you are unfamiliar with the bitmap, you’ll need to experiment. You can try various options and click Preview to see the results. Bitmapping uses U and V axes, which are like X and Y axes but can have any direction and origin. Click Maintain Aspect Ratio to keep the U and V scales equal. By default, bitmaps are tiled, which means that if the scale is less than 1, AutoCAD repeats the pattern to cover the entire object. You can also crop, which creates a decal effect — the pattern is placed just once on the object. 30 539922 Ch25.qxd 5/2/03 9:41 AM Page 889 890 Part IV ✦ Drawing in Three Dimensions Refraction Refraction only applies to Photo Raytrace rendering when you have a transparent (or translucent) material. Refraction is the bending of a light wave when it passes through an object to an object of another density. A higher value increases the refraction. Bump Map Bump maps create the effect of varying heights on the surface of the object — in other words, bumps. You use the bottom part of the dialog box to choose the bump map and for bump map settings. See the sidebar “Mapping” for more information about bump maps. As you complete the dialog box, you can press Preview and see the result as a sphere or cube at any time. When you like the results you see with Preview, click OK. The drawing used in the following Step-by-Step exercise on creating materials, ab25-4.dwg, is in the Results folder of the AutoCAD 2004 Bible CD-ROM. Step-by-Step: Creating Materials 1. If you have ab25-04.dwg open from the previous exercise, use it. Otherwise, open it from your AutoCAD Bible folder (if you did the exercise) or the Results folder of the CD-ROM. 2. Save the file as ab25-05.dwg in your AutoCAD Bible folder. If the Render toolbar is not open, right-click any toolbar and choose Render. 3. Choose Materials from the Render toolbar. The materials that were imported in the previous Step-by-Step exercise are listed on the left. Choose Yellow Plastic and click Duplicate. 4. In the Material Name text box of the New Standard Material dialog box, type Yellow Cheese. 5. With Color/Pattern selected from the Attributes section of the dialog box, click the color swatch to the right of the Color System drop-down list. In the Color dialog box, click the Index Color tab and pick the yellow box. Click OK. 6. Choose Ambient from the Attributes section. Click Lock in the Color section. The color changes to the same yellow as the Color/Pattern swatch. 7. Choose Reflection. Change the value to 0.10 because cheese isn’t very shiny. Click Lock here as well. 8. Choose Roughness. Change the value to 0.75. You can omit transparency because its default value is zero (0). Refraction is irrelevant without a transparency setting. On the CD-ROM 30 539922 Ch25.qxd 5/2/03 9:41 AM Page 890 891Chapter 25 ✦ Rendering in 3D 9. Omit this step and Step 10 if you don’t have a full installation or a custom installation that includes textures. Preview the yellow cheese on a cube. Choose Bump Map from the Attributes section. Choose Find File at the bottom right of the dialog box. In the Bitmap File dialog box, the Textures folder should be current. (If not, find the Textures folder inside the main AutoCAD folder and double-click.) Change the Files of Type drop-down list to *.tga. Choose bmps.tga and click Open. Change the Bitmap Blend to 30. Click Preview again to see the difference. Note that the bumps are too big. 10. Click Adjust Bitmap. In the Adjust Bitmap Material Placement dialog box, check Maintain Aspect Ratio. Change the scale to 2 and click Preview using the cube. The bumps are smaller now. Click OK three times to return to your drawing. 11. Save your drawing. Attaching materials After you import, create, and modify the materials you need, you can attach them to objects. AutoCAD lets you attach materials by object, layer, or color. To attach any material, follow these steps: 1. Choose Materials from the Render toolbar. 2. Choose the material from the list of materials. 3. Use one of these methods to attach the material: • Click Attach to attach a material by selecting the object or objects. AutoCAD temporarily returns you to your drawing and prompts you to select objects. • Click By ACI (AutoCAD Color Index) to attach a material by its color in the drawing. AutoCAD opens the Attach by AutoCAD Color Index dialog box, which lets you choose a color, or colors, by their numbers. • Click By Layer to attach a material by layer. AutoCAD opens the Attach by Layer dialog box, which lets you choose a layer or layers. Attaching materials by layer can be a very efficient method. It requires some plan- ning in advance. For example, if you have a block that is a chair, and if you create it so that the legs are on one layer and the seat and back are on a second layer, then you can easily attach a wood-like material to the legs and a decorative pat- tern to the seat and back. You can assign a material to an object, to its layer, and to its color, which would mean that the object has three materials. AutoCAD gives priority to direct attach- ments by object, then to attachments by color, and finally to attachments by layer. Tip 30 539922 Ch25.qxd 5/2/03 9:41 AM Page 891 892 Part IV ✦ Drawing in Three Dimensions The drawing used in the following Step-by-Step exercise on attaching materials, ab20-b.dwg, is in the Drawings folder of the AutoCAD 2004 Bible CD-ROM. Step-by-Step: Attaching Materials 1. Open ab25-b.dwg from the CD-ROM. 2. Save the file as ab25-06.dwg in your AutoCAD Bible folder. If the Render toolbar is not open, right-click any toolbar and choose Render. This is the same drawing used earlier in the chapter, but all the materials have been imported and modified, and some materials have been attached to objects. Also, the table and chairs have been separated into appropriate layers. 3. Choose Materials from the Render toolbar. Click By Layer. In the Attach by Layer dialog box, choose PINK MARBLE from the Select a Material list. Choose TABLE_TOP from the Select Layer list. Click Attach. The PINK MARBLE material appears next to the TABLE_TOP layer. 4. Choose STITCHED PATTERN from the left list and CUSHIONS from the right list and click Attach. In the same way, attach WOOD-WHITE ASH to the LEGS layer. Click OK. 5. In the Materials dialog box, choose GREEN GLASS and click Attach. AutoCAD finds the bowl, which has already been attached to the GREEN GLASS material and displays the Gathering objects...1 found. Select objects to attach “GREEN GLASS” to: prompt. Select the plate on the table and press Enter to return to the dialog box. 6. Click OK to return to your drawing. 7. Save your drawing. Keep it open if you are continuing to the next Step-by-Step exercise. Using Backgrounds AutoCAD offers some sophisticated features for adding backgrounds to your ren- dering. For example, you can place a picture of the sky in the background. You can also add landscape features such as trees and bushes. This section covers the basics of backgrounds. You have a choice of four types of backgrounds: ✦ Solid places a solid color in the background. You might use solid black for a night scene. ✦ Gradient creates a background of up to three colors in a graded blend. ✦ Image places an image in the background (for example, an image of the sky). ✦ Merge lets you combine your rendering with the image you currently have on your screen. On the CD-ROM 30 539922 Ch25.qxd 5/2/03 9:41 AM Page 892 893Chapter 25 ✦ Rendering in 3D To create a background, choose Background from the Render toolbar to open the Background dialog box, shown in Figure 25-21. If you choose Solid, you can use the current AutoCAD background (usually white or black) or define a color using the same color controls you use for lights and materials, explained earlier in this chapter. If you choose Gradient, you set separate top, middle, and bottom colors. Click the color swatch of the color you want to work with to set its color. Then use the horizon setting to determine the center of the gra- dient. The height determines, in percentage form, where the second color starts. For example, 33 percent would create three equal levels of color. If you want only two colors, set the height to zero (0). Use Rotation to rotate the gradient. Figure 25-21: The Background dialog box If you choose Image, use the Image section to specify a file. If you did a full installa- tion (or a custom installation including textures), you have a number of .tga files to choose from in the \Textures subfolder of AutoCAD. Of course, you can use your own files. You can use the following file types: BMP JPG TGA PNG GIF PCX TIF Merge uses the current AutoCAD background (usually solid white or black) as the background for the rendering. It doesn’t require any settings. You can choose an additional file in the Environment section (at the bottom of the dialog box) to create reflection and refraction effects. You can use the same types of files for environment as for images. AutoCAD maps the image onto a sphere sur- rounding the scene. 30 539922 Ch25.qxd 5/2/03 9:41 AM Page 893 894 Part IV ✦ Drawing in Three Dimensions The drawing used in the following Step-by-Step exercise on adding a background, ab25-6.dwg, is in the Results folder of the AutoCAD 2004 Bible CD-ROM. The graphic file, sky.gif, which you may or may not need, is in the Drawings folder of the CD-ROM. See the instructions in the exercise. Step-by-Step: Adding a Background 1. If you have ab25-06.dwg open, use it. Otherwise, open it from your AutoCAD Bible folder if you did the previous exercise or from the Results folder of the CD-ROM. 2. Save the file as ab25-07.dwg in your AutoCAD Bible folder. 3. If you did a full AutoCAD installation or a custom installation including the textures, choose Background from the Render toolbar. If not, find sky.gif on the CD-ROM and copy it to AutoCAD’s \Support subfolder. Then choose Background from the Render toolbar. 4. Choose Image at the top of the Background dialog box. 5. In the Image section, choose Find File. 6. Open the Textures folder (to locate this folder, choose Tools ➪ Options, click the Files tab, and double-click the Texture Maps Search Path) and choose sky. tga (make sure the Files of Type drop-down list box says *.tga) or choose sky.gif from AutoCAD’s \Support subfolder. Click Open. On the CD-ROM Foggy landscapes The landscape commands enable you to create and edit landscapes. AutoCAD comes with a small library of trees, bushes, people, and a DO NOT ENTER road sign. Choose Landscape New from the Render toolbar, choose an item, and preview it. When you find one that you like, set the geometry. Single Face results in quicker rendering than Crossing Faces but is less realistic. Choose View Aligned if you want the object to always face the viewer, like a tree. You might uncheck this for the road sign — you don’t want the sign to face the viewer from both directions. Set the height (usually in inches) and click Position to place it in your drawing. Note: When you place the landscape object, it appears as a triangle or a rectangle. You don’t see the object until you render the view. Choose Landscape Edit to edit the charac- teristics of an existing landscape object. Choose Landscape Library to edit, delete, and add landscape objects. Choose Fog from the Render toolbar to open the Fog/Depth Cue dialog box. Fog is used to give a sense of distance because objects in the distance often do not appear to be as clear as those close up. Choose Enable Fog to turn fog on. You set the color, near and far dis- tances (where the fog starts and ends), and near and far percentages of fog (how much fog there should be at the near and far distances). 30 539922 Ch25.qxd 5/2/03 9:41 AM Page 894 895Chapter 25 ✦ Rendering in 3D 7. Click Preview. AutoCAD displays the file. 8. Click OK. You won’t see the result until you render the drawing. 9. Save your drawing. If you are continuing to the next Step-by-Step exercise, keep the drawing open. Doing the Final Render You are finally ready to render. Preparing to render can be a long process. If you want, you can choose Render Preferences from the Render toolbar first to open the Rendering Preferences dialog box. This dialog box is an exact copy of the Render dialog box and lets you preset the rendering settings. However, you can also make all these settings in the Render dialog box. To render, choose Render from the Render toolbar. This opens the Render dialog box, shown in Figure 25-22. Figure 25-22: The Render dialog box This dialog box has the following components: ✦ From the Rendering Type drop-down list, choose the type of rendering you want. ✦ In the Scene to Render box, choose a scene. 30 539922 Ch25.qxd 5/2/03 9:41 AM Page 895 896 Part IV ✦ Drawing in Three Dimensions ✦ In the Rendering Procedure section, check one of the options if you want. Query for Selections means that AutoCAD asks you to select objects. Use this to test a rendering on one or more objects. Choose Crop Window to choose a window to render. Choose Skip Render Dialog to render immediately without even opening the dialog box (the next time) — choose Render Preferences on the Render toolbar to change this option when you want the Render dialog box back again. ✦ Set the light icon scale. Use the drawing scale factor for this. ✦ Set the smoothing angle. The smoothing angle determines the angle at which AutoCAD assumes an edge as opposed to a smooth curve. The default is 45 degrees. A lower angle would result in more edges. ✦ In the Rendering Options section, check Smooth Shade to smooth out a multi- edged object. AutoCAD blends colors across adjacent faces. ✦ Check Apply Materials to use the materials you imported and attached. ✦ Check Shadows to generate shadows. You can only create shadows with the Photo Real and Photo Raytrace rendering types. ✦ Check Render Cache to save rendering information in a file. AutoCAD can reuse this information for subsequent renderings, saving time. ✦ Click More Options to open a dialog box that varies with the type of rendering. Usually, you can use the defaults, but you can click Help to get an explanation of each item. ✦ In the Destination section, choose where you want the rendering to appear. The default is Viewport. If you have one viewport, the rendering covers the entire drawing area. If you are using several viewports, the rendering appears in the active viewport. You can also render to the render window. The render window is a regular Microsoft Windows window that lets you copy the render- ing to the clipboard or save the rendering as a bitmap (.bmp) file. Finally, you can save the rendering directly to a file. ✦ Use the Sub Sampling drop-down box to set the sampling of pixels that AutoCAD renders. The default is 1:1, which means all the pixels are rendered. You can speed up the rendering by choosing another ratio. ✦ The Render dialog box has buttons to take you to the Background and Fog/Depth Cue dialog boxes if you decide at the last minute that you want to use these features. When you have finished the settings, click Render to render the drawing. The drawing used in the following Step-by-Step exercise on creating a final rendering, ab25-7.dwg, is in the Results folder of the AutoCAD 2004 Bible CD-ROM. On the CD-ROM 30 539922 Ch25.qxd 5/2/03 9:41 AM Page 896 897Chapter 25 ✦ Rendering in 3D Step-by-Step: Creating a Final Rendering 1. If you have ab25-07.dwg open, use it. Otherwise, open it from your AutoCAD Bible folder if you did the previous exercise or from the Results folder of the CD-ROM. 2. Save the file as ab25-08.dwg in your AutoCAD Bible folder. 3. Choose Lights from the Render toolbar. In the Lights box, choose P1 and click Modify. Change the intensity to 200 and click OK twice to return to your drawing. This is the type of adjustment you often make when doing the final rendering. 4. Choose Render from the Render toolbar. 5. Make sure that Rendering Type is set to Photo Real. 6. Set Scene to Render to MORNING. Check Shadows. 7. Click Render. Wait until AutoCAD finishes the rendering. Look at those shad- ows! Look at the transparent green bowl with the orange in it. Note the sky image outside the window. Okay, so the pink marble is a bit gaudy. 8. To get rid of the ugly UCS icon, choose View ➪ Display ➪ UCS Icon ➪ On. 9. The rendering should look like Figure 25-23, only a lot better because you see it in color on your screen. Save your drawing. Figure 25-23: The final rendering with shadows, transparent objects, and a background Thanks to Autodesk for the sky.gif file. This material has been reprinted with permission from and under the copyright of Autodesk, Inc. 30 539922 Ch25.qxd 5/2/03 9:41 AM Page 897 898 Part IV ✦ Drawing in Three Dimensions Remember that rendering is a trial-and-error process. Don’t expect to get it right the first time. You can probably see several areas for improvement. At this point, you would go back and tweak the lights, materials, and so on until you were satisfied. AccuRender is a rendering program that offers additional rendering capabilities. Look for it in \Software\Chap25\AccuRender. Statistics Choose Statistics on the Render toolbar to open a window that lists statistics relat- ing to your rendering. You can save these to a file. This information is very helpful if you can’t remember which rendering type you used or if you want to compare the time it takes to render a scene using different options. Figure 25-24 shows an example. Figure 25-24: A statistics listing of a rendering Saving rendered images You can save your rendered images and redisplay them at another time. You can also use saved rendered images in other applications and print them from those applications. After rendering to a viewport, choose Tools ➪ Display Image ➪ Save. In the Save Image dialog box, choose the file type .bmp, .tga, or .tif. You can change the size and placement (offset) of the image or accept the defaults. Click OK. AutoCAD opens the Image File dialog box so that you can specify a file name. After selecting a file, click OK again. On the CD-ROM 30 539922 Ch25.qxd 5/2/03 9:41 AM Page 898 899Chapter 25 ✦ Rendering in 3D After rendering to a render window, choose File ➪ Save from that window’s menu and enter a file name. Click OK. AutoCAD saves the image as a .bmp (bitmap) file. To redisplay a rendered image, choose Tools ➪ Display Image ➪ View. Choose the file and click Open in the Replay dialog box. You have the opportunity to crop the image or you can accept the original size. AutoCAD displays the image. Do a regen to return to your regular drawing display. You can import these saved rendered images back into your drawing. Figure 25-25 shows three floating viewports. One of the views shows the rendered image. See Chapter 27 for detailed instructions on importing images. In AutoCAD 2004, you can now plot rendered viewports. See Chapter 17. Figure 25-25: You can include your rendered images in your drawings. Unloading Render When you render, a Render window may open, minimized. You can now close the Render window by clicking its Close box. Closing the Render window when you are finished rendering frees up memory for other tasks. New Feature Cross- Reference 30 539922 Ch25.qxd 5/2/03 9:41 AM Page 899 900 Part IV ✦ Drawing in Three Dimensions Summary In this chapter, I cover the process of rendering. You read the following: ✦ Creating lights ✦ Creating scenes ✦ Importing and creating materials ✦ Attaching materials ✦ Using backgrounds ✦ Rendering a drawing This chapter ends Part IV, “Drawing in Three Dimensions.” Part V, “Organizing and Managing Drawings,” explains how to manage drawings, work with other applica- tions and file types, and use AutoCAD on the Internet. ✦ ✦ ✦ 30 539922 Ch25.qxd 5/2/03 9:41 AM Page 900 Organizing and Managing Drawings Part V is all about how to manage drawings. In Chap-ter 26, I discuss keeping control of your drawings by using the DesignCenter, the new Tool palettes, and the new Communication Center, while also setting and maintaining standards, keeping track of your drawings, handling errors and crashes, and working with prior AutoCAD releases. Chapter 27 explains how to interface with other applications and file formats, including raster (bitmap) images. Finally, Chapter 28 covers getting your drawings onto the Internet. ✦ ✦ ✦ ✦ In This Part Chapter 26 Keeping Control of Your Drawings Chapter 27 Working with Other Applications Chapter 28 Getting on the Internet ✦ ✦ ✦ ✦ P A R T V 31 539922 PP5.qxd 5/2/03 9:41 AM Page 901 31 539922 PP5.qxd 5/2/03 9:41 AM Page 902 Keeping Control of Your Drawings When you create a drawing in AutoCAD, you not onlycreate objects, you create a complex structure to support those objects. You create named blocks, layers, lay- outs, text styles, dimension styles, and linetypes to help define those objects. You spend a lot of time creating them, too! All of these named drawing components can be reused and organized for greater efficiency. Having standards for named drawing components, such as layers and text styles is important for consistency and readability. AutoCAD offers a comprehensive system for maintaining CAD standards. Security is also important and AutoCAD 2004 offers new features to help. You also need to keep track of your drawings and make sure that they are accessible. Archiving and repair procedures are important in any CAD environment. Accessing Drawing Components with the DesignCenter I mention the DesignCenter many times in this book — for example, in Chapter 11 on layers and Chapter 18 on blocks. In this chapter, I cover the DesignCenter in detail. You can use the DesignCenter to easily drag named drawing components from one drawing to another. You can access this drawing con- tent from drawings on your hard drive, on a network drive, or over the Internet. You never need to re-create them again. Autodesk calls this mining your design. You can even drag raster images directly into your drawing. 26C H A P T E R ✦ ✦ ✦ ✦ In This Chapter Working with the DesignCenter Accessing Drawing Content with the Tools Palette Setting standards for drawings Organizing your drawings Maintaining security Keeping track of referenced files Handling errors and crashes Managing drawings from prior AutoCAD releases ✦ ✦ ✦ ✦ 32 539922 Ch26.qxd 5/2/03 9:42 AM Page 903 904 Part V ✦ Organizing and Managing Drawings You can do the following with the DesignCenter: ✦ Browse and insert named drawing components, including blocks, xrefs, lay- ers, text styles, dimension styles, linetypes, and layouts. You can also access custom objects created by third-party applications that work with AutoCAD. ✦ Create shortcuts to drawings and locations that you use most. ✦ Search for drawings and named drawing components. ✦ Open drawings by dragging them into the drawing area. ✦ View and insert raster image files by dragging them into the drawing area. Navigating with the DesignCenter To open the DesignCenter, choose DesignCenter from the Standard toolbar or choose Tools ➪ DesignCenter. As a shortcut, press Ctrl+2. The DesignCenter appears as shown in Figure 26-1. The DesignCenter has been updated to use the new palette interface — the same one you see in the Properties palette. Four tabs provide access to folders, open drawings, history, and the new DC Online, where you can find content provided by Autodesk, manufacturers and other users. Figure 26-1: The DesignCenter with the Folders tab displayed Description Area Tree view Tree view toggle Preview Description Content area Preview area New Feature 32 539922 Ch26.qxd 5/2/03 9:42 AM Page 904 905Chapter 26 ✦ Keeping Control of Your Drawings The Folders tab displays a tree view of any location — your hard drive, network, or the Internet — that you can access. This tree view is very similar to Windows Explorer. Click the plus sign next to a drive or folder to display its contents. Use the vertical scrollbar to display any location. A selected drawing displays its named components in the content area on the right side of the palette. You can also click the plus sign next to a drawing to see (in the tree view side) the named components it contains. Then click a component type, such as blocks, to see a list of the blocks in the drawing, as shown in Figure 26-1. Click Preview on the DesignCenter toolbar to see a preview in the preview pane of blocks, drawings, and raster images. Click Description to display a description, if one is saved. After you narrow your search, you may want to click Tree View Toggle to tog- gle off the tree view, hiding the navigation pane. By default, the navigation pane displays your desktop, meaning the files and folders on your hard drive and network. To narrow down your search, you can click two other tabs from the DesignCenter: ✦ Open Drawings displays currently open drawings. ✦ History displays the most recently opened drawings. Finding named components and drawings What do you do if you don’t know the location of the drawing you want? Suppose you know the name of the layer, but not which drawing it is in. The DesignCenter includes a Search feature to help you out. Choose Search from the DesignCenter toolbar to open the Search window, shown in Figure 26-2. (You can also right-click in the Content area and choose Search.) Here’s how to use the Search window: ✦ Click the Look for drop-down list to choose what you are looking for. You can look for blocks, dimension styles, drawings, drawings and blocks, hatch pat- tern files, hatch patterns, layers, layouts, linetypes, text styles, and xrefs. ✦ Click the In drop-down list to specify the drive you want to look in. By default the Search subfolders check box is checked so that AutoCAD searches all fold- ers and subfolders within the drive. ✦ Use the tabbed area to specify the name of the components you are looking for. The tab’s name and content changes depending on what you chose in the Look for drop-down box. For example, if you chose Layers, the tab is called Layers and asks you for the name of the layer. If you are looking for drawings, you have three tabs to work with: 32 539922 Ch26.qxd 5/2/03 9:42 AM Page 905 906 Part V ✦ Organizing and Managing Drawings • The Drawings tab enables you to choose to look for a drawing by file name (the default), title, subject, author, or keywords. Choose one of these options in the In the field(s) drop-down list. Then type the text you want to look for in the Search for the Word(s) text box. You can use the wildcards * (to substitute for any number of characters) and ? (to substi- tute for any one character). Specifying a drawing’s title, subject, and key- words is discussed later in this chapter. • The Date Modified tab enables you to search by the last date the file was saved or modified. You can specify a range of dates or look in the last x days or months. • The Advanced tab enables you to search for text in drawing descrip- tions, block names, attribute tags, and attribute values. You can also search here by drawing size. ✦ When you have created your specifications, click Search Now. Figure 26-2: Use the Search window to locate drawings and drawing components. See Chapter 18 for information on creating block descriptions when you create a block. The main reason for creating a block description is to display it in the DesignCenter and to be able to use it in a search on the Advanced tab, as just described. Using the Favorites folder The Favorites folder is a Windows convention that helps you to find files that you use often. This folder contains shortcuts to actual files. The files remain in their original locations. Choosing a file from the Favorites folder has the same effect as choosing the file from its source location. Cross- Reference 32 539922 Ch26.qxd 5/2/03 9:42 AM Page 906 907Chapter 26 ✦ Keeping Control of Your Drawings AutoCAD 2004 creates an Autodesk subfolder within the Favorites folder, where you can store shortcuts to drawings and other files that you use often. You can then easily open the Favorites folder and find these files. Favorites is one possible place to keep drawings that contain block libraries. To add a shortcut to Favorites, right-click the drawing (or other file) in the DesignCenter and choose Add to Favorites. If you right-click in the content pane and choose Add to Favorites, AutoCAD adds a shortcut to the entire content of the folder. This is great for adding all the items in a folder at once, but if you do it inadvertently, you could end up with lots of junk in Favorites. To add one item, remember to select it first. To access the drawings in Favorites, click Favorites on the DesignCenter tool- bar. You can also right-click the content pane and choose Favorites. AutoCAD displays the Favorites folder in the content pane. To move, copy, or delete shortcuts from Favorites, right-click the Content pane and choose Organize Favorites. Accessing named drawing components As soon as you have the item you need in the content area, you need to insert it into your drawing. If you used the Search window to locate a file, you can also insert directly from results you get. You can either drag the item onto the drawing area or right-click it and choose an option. Sometimes these two methods provide slightly different results. In this section, I explain how to insert drawing compo- nents into your drawing. Inserting drawings You can insert an entire drawing into your drawing. Choose the drawing’s folder in the navigation pane so that the drawing appears in the content area. Drag the draw- ing’s icon onto the drawing area. AutoCAD prompts you for an insertion point, scale, and rotation angle, using the -INSERT command, which prompts you on the command line. If you right-click the drawing, you can choose to insert the drawing as a block or attach it as an xref. Opening drawings You can open a drawing using the DesignCenter. Display the drawing in the content pane, right-click it, and choose Open in Application Window. AutoCAD opens the drawing, keeping your current drawing open as well. Caution 32 539922 Ch26.qxd 5/2/03 9:42 AM Page 907 908 Part V ✦ Organizing and Managing Drawings Inserting blocks In Chapter 5, I explain that you can use the Units dialog box (choose Format ➪ Units) to set a unit, such as inches, for automatically scaling drawings when they are inserted from the DesignCenter. You can insert blocks in two ways: ✦ If you drag the block’s icon onto the drawing area, AutoCAD uses Autoscaling, which compares the current drawing’s units with those of the block and scales the block appropriately, using the value set in the Units dialog box. AutoCAD uses default scale and rotation. ✦ If you double-click the block’s icon or right-click it and choose Insert Block, AutoCAD opens the Insert dialog box where you can specify the insertion point, scale, and rotation. Inserting raster images A raster image is a bitmap graphic file. You can insert raster images directly into your drawing — they don’t have to be within an AutoCAD drawing. See Chapter 27 for more information on raster images, including determining which type of files you can import, attaching images, clipping images, and control- ling how they are displayed. To attach a raster image, drag its icon onto the drawing area. AutoCAD prompts you for an insertion point, scale, and rotation angle on the command line. Knowing the appropriate scale of an image before inserting it is often hard. When you move the cursor at the Specify scale factor or [Unit] : prompt, you can see a bounding box that will help you visualize the resulting size of the image. Attaching an xref To attach or overlay an xref, right-click its icon and choose Attach Xref to open the External Reference dialog box. Choose either Attachment or Overlay in the Reference Type section. Specify an insertion point, scale, and rotation (or choose to specify them on-screen) and click OK. If you drag the xref onto the drawing area, AutoCAD provides prompts on the com- mand line similar to those of the -INSERT command. Inserting layers To insert a layer into a drawing, drag its icon onto the drawing area. You can drag multiple layers at one time. To select a contiguous group, click the first layer, press and hold Shift, and click the last layer. To select individual multiple layers, click the first layer, press and hold Ctrl, and click any other layer you want to insert. You can also double-click a layer to insert it. Tip Cross- Reference 32 539922 Ch26.qxd 5/2/03 9:42 AM Page 908 909Chapter 26 ✦ Keeping Control of Your Drawings AutoCAD does not check for duplicate layer names. If you try to insert a layer with the same name as a layer in your current drawing, you see a message: Layer(s) added. Duplicate definitions will be ignored. You should check for duplicate layer names before trying to insert layers from the DesignCenter. Inserting content from DC Online The new DC Online tab provides access to online resources, including standard parts and manufacturers’ information. Figure 26-3 shows the outline of the DC Online content. To insert any content, select it and drag it into your drawing. Follow the prompts for insertion point and so on. Figure 26-3: The DC Online tab of the DesignCenter offers a large selection of content that you can drag into your drawing. Controlling the DesignCenter display The DesignCenter provides several controls that help you manage its display. A great feature of the DesignCenter is the preview pane. Click Preview on the DesignCenter toolbar to open this pane. Then select the item in the content pane. You may or may not see a preview of a block. (The new Block Definition dia- log box specifically lets you create a preview icon.) Usually, you will see a preview of drawings and raster images. No previews exist for layers, linetypes, text styles, and so on. 32 539922 Ch26.qxd 5/2/03 9:42 AM Page 909 910 Part V ✦ Organizing and Managing Drawings If you saved a description with a block, select the block in the content pane and click Description on the DesignCenter toolbar to see the description. To set the view, choose Views from the DesignCenter toolbar. The drop-down arrow lets you choose from four types of displays: large icons, small icons, list, and details. You can only see details for drawings and other files — AutoCAD dis- plays their size and type. If you make changes in the structure of a folder while the DesignCenter is open, for example by deleting a drawing using Windows Explorer, right-click the navigation or content pane and choose Refresh. AutoCAD re-reads the data and refreshes the list. To dock the DesignCenter, right-click the title bar and choose Allow Docking. Then drag the DesignCenter window to the left or right of your AutoCAD window. To collapse the DesignCenter down to its title bar when you’re not using it, right-click the title bar and choose Auto-hide; whenever you move the mouse cursor off the DesignCenter it collapses. Just move the cursor back onto the title bar to expand it again. Sometimes the DesignCenter docks when you are trying to drag it past the AutoCAD application window. To avoid unwanted docking, either uncheck Allow Docking on its title bar or press Ctrl as you drag. The drawings used in the following Step-by-Step exercise on using the DesignCenter, ab26-a.dwg and

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