It s A Material World After All Alexander L.. Wood CAD Training Solutions, LLC

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1 November 30 December 3, 2004 Las Vegas, Nevada It s A Material World After All Alexander L.. Wood CAD Training Solutions, LLC GD21-3 Learn the basics of taking your 3D model into a rendered presentation. Learn some basics of lighting, material mapping, and editing using the rendering features that core AutoCAD has to offer. This class is designed for users who are proficient with 2D design and drafting using Autodesk software, who have some basic 3D modeling experience (primitive and solid creation/manipulation as well as 3D scene setup), and who want to work with the rendering, lighting, and materials tools in AutoCAD. If you re interested in this course, you ll also want to check out the class It s a 3D World After All. About the Speaker: Alex has more than 13 years experience with AutoCAD, starting with Release 9. He holds Autodesk certification for nearly all Autodesk products. Alex works as IT Manager for WGM Group Inc, a Montana-based engineering and land-planning firm. He also has 4 years of experience as technical manager at an Autodesk System Center. Alex is expert in numerous fields, including utilities drafting, civil/environmental engineering design, 3D hydraulic/electric machine design and fabrication, CADD project management, architectural drafting and visualization, CADD services systems/personnel management, and Autodesk product support. cts_awood@yahoo.com

2 It s a Material World After All Topics Covered: Accessing Materials and the Material Library The Render Toolbar The Materials Dialog The Material Libraries Loading Materials Attaching Materials to Solids Attachment options Viewing Materials Modifying Exisiting Materials Two Types of Materials Editing Basic Materials Editing Raster-based Materials Basic Material Mapping Adding and Modifying New Materials Creating a New Material 3D Scene Setup Lighting Light Dialogs Scenes Rendering Background Options Rendering for Presentation Extras AutoCAD System Variables that Affect Rendering 2

3 GD21-3 Introduction: As we develop our 3D models we eventually need to be able to present them, whether digitally or in hardcopy. Core AutoCAD offers basic material, lighting, and rendering capabilities. We can apply materials to the objects in our drawing using basic colored materials or by using imagery from a number of different sources for more real world rendered materials. We can add basic lighting using point lights, distant lights (for Sun objects), and spotlights. Eventually we can combine all this into rendered images that can be generated specifically for printing, for ing and web use, or for projected presentations. Utilizing the basic Rendering capabilities that AutoCAD has to offer we can present our 3D information in ways that communicate our ideas more easily and with greater impact. The purpose of this course is to allow you to efficiently, yet creatively, develop basic rendered scenes in AutoCAD and AutoCAD based applications. General Procedures for developing Rendered presentations Create the 3D model and setup a view for presentation Load and attach materials to the 3D objects Setup lighting Add background objects as desired Test and modify Materials, Lights, and Backgrounds as necessary Render presentation to file 3

4 It s a Material World After All Accessing Materials and the Materials Library The Render Toolbar Many of the tools we will use will be available from the Render Toolbar. The Render Toolbar is found as any other Toolbar in AutoCAD, by right-clicking on any existing AutoCAD Tool Button and selecting the Render option, or under the View Menu => Toolbars option and checking the Render Toolbar. Render Access the Render dialog Scenes Access saved Scenes Lights Create and Modify Lighting objects Materials Create and Modify materials and Attach them to drawing objects Materials Library Access the default and custom materials libraries and bring them into a current drawing Background Modify rendering backgrounds Mapping Modify materials for specific objects and representations 4

5 GD21-3 Accessing Materials You can access the Materials Dialog from the Render Toolbar AutoCAD includes a library of materials to get you started; however we can easily create or customize our own materials. In a new drawing, for drawing size consideration, there will not be any materials loaded initially. We can create a new list of materials from scratch, load existing materials from the predefined library or from custom libraries, and then modify individual materials for specific uses. List of Materials loaded in current drawing Preview Materials Preview Type Access Materials Libraries Modify a material currently loaded in the drawing Duplicate a currently loaded material Create a new material Specify a new Standard, Granite, Marble, or Wood material. Select an object to display information about attached materials Attach/Detach loaded materials to Objects, to Colors, or to Layers We can attach and detach materials to objects, colors, and layers. We can Preview materials in this dialog, as we create and modify them, however it is not necessarily indicative of how the material will appear when actually attached to our objects and rendered. We will usually want to see the materials as they are applied to our objects to ensure the quality and look we want to achieve. We can do this through test renderings or we can see them represented on screen by adjusting display options in AutoCAD. From the Materials Dialog we can also access materials libraries to bring additional materials into our current drawing. 5

6 It s a Material World After All Accessing the Materials Library The Materials Libraries can be accessed from the Materials Library button in the Materials Dialog. List of Materials loaded in current drawing Preview materials Choose between different material libraries Select materials Preview type Purge un-used materials Save a custom materials library from the current drawing materials list Open Material Libraries Save a custom materials library from the current library Import, Export, and Delete materials from the current drawing or current library We can open materials libraries and then select materials and Import them into the current drawing. We can also Export materials that we have created or modified in the current drawing back into a selected library. As we import materials into a drawing we can save that list as a new custom material library. If we have modified the Current Library by exporting materials we can save that list as well. The file extension for a Materials Library is.mli We can also preview materials here but, as in the Materials Dialog, the preview is just a basic representation of the selected material. 6

7 GD21-3 Loading Materials To load a Materials Library into the current drawing click the open button and browse to the desired library. Use the Current Library dropdown to switch between libraries. To load materials into the current drawing simply select a material in the Current Library list and then click the Import button. You will see the material listed under the Current Drawing list. When you exit out of the Materials Library Dialog and then launch the Materials Dialog you see the imported materials listed and ready for use. Once a material has been loaded we can use the Materials Dialog to modify and attach the materials. Select a desired material and then click the Import button Note that we can use Ctrl+Left-click Click and Drag to select multiple materials to Import 7

8 It s a Material World After All Attaching Materials to Solids Attachment options We can attach materials to our solid objects through three methods; By ACI Attach The Attach option allows you to apply materials directly to objects selected in the model. The Attach option overrides the other options, By ACI and By Layer. While in the Materials Dialog, select the material you want to attach from the materials list then select the object(s) in the model where you want to apply the materials. Detach The Detach option removes materials that have been attached using the attach options. The By ACI option allows you to attach materials to specific colors using the AutoCAD Color Index (ACI). This affects layer color as well as objects that have a color specifically set as a property. By selecting the By ACI button we can select a material from the list on the left, select a color or multiple colors to attach to, and then select the Attach button. You will see the color and associated material in the Select ACI field on the right We would use the detach option to materials from specific colors. remove By Layer This is considered Best Practice. The By Layer option attaches materials to all objects that reside on the selected layer(s). Select the desired material in the materials list on the left, select the layers you want to apply the material to on the right and then click the Attach button. You will see the layer and the associated material in the Select Layer list on the right. We would use the Detach option to remove materials from specific layers. 8

9 GD21-3 Viewing Materials As we attach materials we will want to see their effect on our presentation and, in the case of Raster-based materials, how they map to our objects. With materials we can do a quick rendering to the Viewport to study our scene. This results in better quality rendering test but we have to wait for the rendering to generate and we are limited to the view being rendered. Another option is to change Display options in AutoCAD, which will allow us to use the Flat or Gouraud Shaded shademodes to view the materials applied to our objects. The material quality and mapping is decreased and this option is video and memory intensive, however it allows us to 3D Orbit our model and view the materials in realtime. In the Options Dialog under the System Tab we can click the Properties Button to access the Graphics System Configuration. In the Graphics System Configuration Dialog there are a number of options to increase or decrease detail, and decrease or increase performance respectively. To view materials while using shademodes we want to turn on the Render Options checkbox as well as Enable materials and Enable textures. We can also adjust transparency quality. If you have used the Flat-Shaded or Gouraud Shaded shademodes you should be familiar with the way AutoCAD solids are natively shaded. A shaded object in AutoCAD will essentially have a fairly realistic look. With the Display Options turned on, Materials are applied and we have some indication of what our models may look like when fully rendered. Using the Display Options within AutoCAD allows you to see materials, in real time, as they are applied to the objects. 9

10 It s a Material World After All Modifying Existing Materials Two Types of Materials There are basically two types of materials in AutoCAD: One type of material is typically based on color and can have attributes applied to it such as Ambient Light values, Reflection values, Roughness, and Transparency. The other type of material is based on a raster image. These materials can use Bitmaps (BMP), TIFFs, JPEGs, PNG files, Targa files, as well as a number of other raster file types. We can use imagery from digital photos to develop more real world quality materials such as siding or brick, different textured metals, or landscaping. Additionally, a Raster-based material can be applied to standard materials to take advantage of the standard material attributes. 10

11 GD21-3 Editing Basic Materials We can edit materials that have been loaded into the current drawing through the Materials Dialog. Select the Material you want to modify then click the Modify button. You can also double-click on the selected material. Additionally, you can click the Duplicate button to create a copy of the material to preserve the integrity of the original. This will open the Modify Standard Material Dialog. Rename the material Select different attributes to modify Adjust the values of attributes Create a Mirror material Adjust colors when available. By adjusting the values of different attributes we can create numerous material effects. We can modify the color of our materials as well as the color of their ambient shadow or the color of their reflection through the Color, Ambient, and Reflection attributes. The Roughness attribute adjusts the roughness or shininess of an object respectively. We can create transparent or glass-like materials and even mirror materials. Additionally we can add raster image overlays to the object to create even more variations. 11

12 It s a Material World After All Editing Raster-based Materials There are two basic ways to modify a raster-based material. One way is to simply edit the image that the material is based on. We can use image-editing applications, of differing complexity, to accomplish this. We can also modify certain aspects of a raster-based material through the Modify Standard Material dialog. After selecting the material and clicking Modify in the Materials Dialog we can click the Adjust Bitmap button in the Modify Standard Material dialog. Adjust Bitmap This will open the adjust Material Bitmap Placement Dialog. Locate a raster image for the material Adjust Scale and Offset values using sliders. Tile the material or Crop it to an object. Adjust Scale and Offset values using numerical values. Specify Fixed Scale for Tiled images or Fit to Object Force the image to maintain horizontal and vertical proportions. Scale and Offset use U and V values where U is the horizontal value and V is the vertical value. 12

13 GD21-3 Basic Material Mapping For certain materials and objects we may have to apply Material Mapping. Mapping helps us to project and maintain a material image on specific objects. This would be used to map an image to a four-sided shape, such as a poster or billboard, or to a cylinder, for a textured column or a material map for a metal pipe. Pay attention to the current orientation of the object in regards to the UCS, to control the orientation of the mapped image. We Map and manipulate materials, to an object, based on the current UCS. This is just an example of Basic Material Mapping as attached to a rectangular and a cylindrical solid. The Mapping option or SetUV command is applied per object. Although some of the specifics of this command are outside the scope of this course, the basics for a Planar or Cylindrical mapping are quite simple. Start the SETUV command, select the specific object, and then select the mapping that applies. For a Planar mapping, select the Parallel Plane that applies the best for the object desired. Cylindrical Mapping has a direct effect on how an image is mapped to a cylinder. Cylinder without mapping applied Cylinder with mapping applied 13

14 It s a Material World After All For a sign, in this example, we will select the specific object and set the mapping for the YZ plane. This assures that the specific object Knows how the material is assigned. Here we also have the options to adjust the offsets and rotation values of the bitmap or raster image. Here we see the bitmap image mapped to the ZY plane and rotated at a 45-degree angle. Material mapping, at first, is a trial and error procedure, but it does become an evident function the more one utilizes the specific options. 14

15 GD21-3 Adding and Modifying New Materials Creating a New Material Within the Materials dialog we have the ability to create New Materials. This allows us to take advantage of what we have learned from the prepared materials and apply that to what we need in our presentations. In the Materials Dialog we can create new, custom materials from scratch. Under the New button we can select a New Standard (Color-based) material or a new Granite, Marble, or Wood material. Each starts with certain attributes, which we can modify for our specific needs. Once we have chosen the basic material Template we can adjust the attributes for that material specifically. An attribute of a material can be the bitmap (raster-based image) that is applied or connected with that material. This is ideal for creating a materials with a more real-world look. To create a Bitmap (Raster-based) material within a new material we can choose to do so in the New Material Dialog. This also allows us the opportunity to adjust the bitmap, or the properties of the image as needed. By default, the material bitmaps or Raster images included with AutoCAD are stored in the C:\Documents and Settings\All Users\Application Data\Autodesk\<application>\enu\Textures directory. This can be re-pathed through the Options Dialog => Files Tab => Texture Map Search Path New Materials are added to our Current Drawing. You can save these custom materials to a Materials Library for future use. 15

16 It s a Material World After All 3D Scene Setup Lighting Lighting adds a new dimension, a new depth to the presentations that we create. In a basic rendering, a model with applied materials, our model has a basic realistic feel. Lighting adds shadow effects, which creates a presentation with depth as well as a more real- world feel. The basic AutoCAD lighting effects can be used for Point Lights (similar to an Incandescent light bulb), a Distant Light (used for a Daylight or Sun effect), and a Spotlight (allowing for a target direction and a hotspot and fall off attribute). With the combination of any or all of these we can create lighting compositions that, at the least, infer to a real world situation. Light objects in the drawing will be represented by a block, which is inserted when the new light is created. 16

17 GD21-3 Light Dialogs The Light Dialog gives us options to create new Lights and to control the Ambient light intensity and color. Ambient light provides constant illumination in the model. Modify existing Lights Set Ambient Light Intensity List of Lights i n Current Drawing Delete an existing Light Select a Light in the drawing to display in the list Set Ambient Light Color Select and Create a New Light We can then modify an individual Light s position, and in the case of a Spotlight, it s Target. We can modify a Light s color and intensity. With a Spotlight we can modify the Hotspot and Falloff. Additionally we can adjust whether or not a specific Light casts a shadow. Name a Light Change the Intensity of a Light Modify Hotspot and Falloff for a Spotlight Modify a Light s position and Show a Light s position in coordinate values Adjust Light color Turn Shadows On or Off for a Light 17

18 It s a Material World After All Scenes A Scene is a View associated with a selection of lights. We can saved Named Views in our Model and then add any number of lights. A Scene allows to us to quickly switch between different views and arrangements of lights. For instance we could set up Scenes for daytime and nighttime renderings. Create a new Scene List of saved Scenes Modify an existing Scene Delete an existing Scene the View and the Lights (using Ctrl+Select) associated with the Scene. To cre ate a sce ne we sim ply sel ect Name a Scene Select a View Select associated lights In the Render Dialog we can choose the Scene to Render. Rendering 18

19 GD21-3 Background Options We can choose backgrounds for our renderings based on color or based on imagery. The Background Dialog c an be accessed from the Render Toolbar or from within the Render Dialog. By default AutoCAD will use the current Model Space display background for renderings. We can select specific colors for our Background and even apply Gradient fills. We can use imagery, including digital photos, for our Backgrounds. Supported Background imagery formats include, BMP, JPG, PCX, TGA, and TIFF files. This gives us the capability of taking a digital photo of a site, for example, and using real-world imagery as a background for our rendered model. 19

20 It s a Material World After All The Background dialog is a simple interface to adjust what our background looks like. Choose a Solid, Gradient, or an Image Background Select a single color for a Solid Background or adjust Top, Middle, and Bottom colors for a Gradient Background Select a file for an Image Background and Adjust Bitmap properties We can also adjust the properties of the Background Image Adjust Scale and Offset for a Background Image Fit a Background Image to the screen Choose Tile and Crop options In most cases we will simply use the Fit to Screen options and adjust our Model and View to get the Background to reflect what we want to see. 20

21 GD21-3 Rendering The Render Dialog The Render Dialog is where all of our setup culminates. We can do basic Renderings to our AutoCAD display to test the different elements as we add them. Eventually we can Render, at High-resolution, to a file for , Web, or other presentation uses. As taken from the AutoCAD Help Menu, AutoCAD Render provides three rendering types: Render, the basic AutoCAD rendering option for best performance Photo Real, the photorealistic scanline renderer, which can display bitmapped and transparent materials and generate volumetric and mapped shadows Photo Raytrace, the photorealistic raytraced renderer, which uses ray tracing to generate reflections, refraction, and more precise shadows Choose a Rendering Type Choose to Render a selection set Choose a Scene to Render Select basic Rendering options View More Options depending on Rendering Type Launch the Background Dialog Select a Destination for the Rendering 21

22 It s a Material World After All When we are ready to finalize the Rendering and then output the rendering to a file, we can change the Destination to File and then select More Options to set specific attributes for the File. We can output to a BMP, PCX, Postscript, TGA (Targa), or TIFF file format. We can output at a number of different resolutions and different color depths, each increasing step creating better resolution images at the cost of file size and lengthened rendering times. A TIFF rendered at 1600x1280 and 24 bits color will generate around a 5-8 Megabyte file, suitable for printing at around an 8x10 size. Choose Output file type and output file resolution Choose color depth for the output file Select image options for TGA or Postscript files 22

23 GD21-3 Extras AutoCAD System Variables that Affect Rendering Here are two basic System Variables that have some affect on Rendering. The definitions of the variables are taken from the AutoCAD Help Menu FACETRATIO - Controls the aspect ratio of faceting for cylindrical and conic ShapeManager solids. A setting of 1 increases the density of the mesh to improve the quality of rendered and shaded models. FACETRES - Adjusts the smoothness of shaded and rendered objects and objects with hidden lines removed. Valid values are from 0.01 to By increasing these variables we create more refined renderings at the expense of file size and rendering times. Summary This is a brief and basic look at opening the door to the Rendering world. There are of course much higher end applications, such as Autodesk VIZ or MAX, with more options and capabilities for creating photo-realistic rendering. However, by leveraging the AutoCAD tools that we have available; we can develop fairly realistic 3D renderings without much of a learning curve and without having to learn a whole new software interface. 3D renderings allow us to visualize and communicate information to people or clients that might not have the experience that we have in interpreting standard plan sets. They also give us an opportunity for value-added presentations that could potentially set us apart from the competition. With practice, 3D manipulation and Rendering in AutoCAD can be an efficient way to present our information in a whole new light (pardon the pun ). Thank you all very much for attending and have a great AU2004 experience. Alex Wood Owner/CADD Instructor CAD Training Solutions, LLC alex@cadtrainingsolutions.com Cts_awood@yahoo.com 23