It’s A Material World After All

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.

[email protected]

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

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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 emailing 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

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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

Materials Library – Access the default and custom materials libraries and bring them into a current drawing

Materials – Create and Modify materials and Attach them to drawing objects

Lights – Create and Modify Lighting objects

Scenes – Access saved Scenes

Background – Modify rendering backgrounds

Mapping – Modify materials for specific objects and representations

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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.

Modify a material currently loaded in the drawing

Select an object to display information about attached materials

Access Materials Libraries

Preview Type

Preview Materials

List of Materials loaded in current drawing Duplicate a

currently loaded material

Create a new material

Specify a new Standard, Granite, Marble, or Wood material.

Attach/Detach loaded materialsto 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.

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Accessing the Materials Library The Materials Libraries can be accessed from the Materials Library button in the Materials Dialog.

Save a custom materials library from the current library

Import, Export, and Delete materials from the current drawing or current library

Open Material Libraries

Select materials

Preview type

Preview materials

Choose between different material libraries

Purge un-used materials

Save a custom materials library from the current drawing materials list

List of Materials loaded in current drawing

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.

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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.

Note that we can use Ctrl+Left-click Click and Drag to select multiple materials to Import

Select a desired material and then click the Import button

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Attaching Materials to Solids Attachment options We can attach materials to our solid objects through three methods;

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.

By ACI

The ‘By ACI’ option allows you to attach mto specific colors using the AutoCAD Color Inde(ACI). This affects layer color as well as objects that have a color specifically set as a property.

By selectin

aterials x

g the ‘By ACI’ button we can select a

color and associated material in

remove

By Layer

This is considered ‘Best Practice’.

rials to

desired material in the materials

e associated

We would use the Detach option to remove materials f om specific layers.

material from the list on the left, select a color ormultiple colors to attach to, and then select the Attach button.

You will see thethe ‘Select ACI’ field on the right

We would use the detach option tomaterials from specific colors.

The ‘By Layer’ option attaches mateall objects that reside on the selected layer(s).

Select thelist 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 thmaterial in the ‘Select Layer’ list on the right.

r

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In the Graphics System Configuration Dialog thdetail, and decrease or increase performance re

To view materials while using shademodes we want to as Enable materials and Enable textures. We can also ad

If youshAutoCA

With the Display Options turned on, Materials are applied and we have some indication of

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 real-time.

we can click the Properties Button to access the Graphics System Configuration.

ere are a number of options to increase or decrease spectively.

turn on the Render Options checkbox as well just transparency quality.

have used the Flat-Shaded or Gouraud Shaded ademodes you should be familiar with the way

D solids are natively shaded.

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.

A shaded object in AutoCAD will essentially have a fairly realistic look.

In the Options Dialog under the System Tab


Modifying Existing Materials Two Types of Materials

als in AutoCAD:

cally based on color and can have attributes applied to it such as 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

Additionally, a Raster-based material can be applied to standard materials to take advantage of the standard material attributes.

There are basically two types of materi

One type of material is typiAmbient Light values, Reflection values, Roughness, and

or brick, different textured metals, or landscaping.

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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.

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.

he Roughness attribute adjusts the roughness or shininess of an object respectively.

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.

l

Create a

Rename the material

Select different

Adjust the values of attributes

Adjust colors

This will open the Modify Standard Material Dia

og.

attributes to modify Mirror

material

when available.

T

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.

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E

Adjust Scale andOffset values using sliders.

Adjust Scale andOffset values using numerical values.

he material or Crop it to an object.

Specify Fixed Scale for Tiled images or Fit to Object

his will open the adjust Material Bitmap Placement Dialog.

Force the image to maintain horizontal and vertical proportions.

Tile t

diting Raster-based Materials here are two basic ways to modify a raster-based material.

e way is to simply edit the image that the material is based on.

ns, of differing complexity, to accomplish this.

l through the Modify Standard

ust

fset use U and V values where U is the horizontal value and V is the vertical value.

T

On

We can use image-editing applicatio

We can also modify certain aspects of a raster-based materiaMaterial dialog.

After selecting the material and clicking Modify in the Materials Dialog we can click the AdjBitmap button in the Modify Standard Material dialog.

Adjust Bitmap

Locate a raster image for the

material

T

Scale and Of

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asic Material Mapping or certain materials and objects we may have to apply Material Mapping.

This would be used to map an four-sided shape, such

as a poster or billboard, or to a extured column or

.

ds

rials,

his is just an example of Basic aterial Mapping as attached to a ctangular and a cylindrical solid.

hn tical mapping are quite simple.

n

s a direct effect on how an image is mapped

Cylinder without mapping applied

linder with mapping applied

BF

Mapping helps us to project and maintain a material image on specific objects.

The Mapping option or SetUV command is applied per object.

Althougcommacourse,

image to a

cylinder, for a ta material map for a metal pipe

Pay attention to the current orientation of the object in regarto the UCS, to control the orientation of the mapped image.

We Map and manipulate mateto an object, based on the current UCS.

TMre

some of the specifics of this d are outside the scope of this he basics for a Planar or

Cylindr

d then select the mapping that applies.

lies the best for the object desired.

Start the SETUV command, select the specific object, a

For a Planar mapping, select the Parallel Plane that app

Cylindrical Mapping hato a cylinder.

Cy


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

e gree 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.

rotation values of the bitmap or raster image.

Here we see the bitmap image mapped to the ZY planand rotated at a 45-de

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Adding and Modifying New Materials Creating a New Material

e New Materials.

tage of what we have learned from the prepared materials and apply

n select a New tandard (Color-based) material or a new Granite, arble, or Wood material.

’

ted’ terial.

eate a Bitmap (Raster-based) material within a new material we can

oose to do so in the New Material ialog.

f e as needed.

o

You can save these custom materials to a Materials Library for future use.

Within the Materials dialog we have the ability to creat

This allows us to take advanthat to what we need in our presentations.

In the Materials Dialog we can create new, custom materials from scratch.

Under the New button we caSM

Each starts with certain attributes, which we can modify for our specific needs.

Once we have chosen the basic material ‘Templatewe can adjust the attributes for that material specifically.

An attribute of a material can be the bitmap (raster-based image) that is applied or ‘connecwith that ma

This is ideal for creating a materials with a more real-world look.

To cr

chD

This also allows us the opportunity to adjust the bitmap, or the properties othe imag

By default, the material bitmaps or Raster images included C:\Documents and Settings\All Users\Application Data\Autdirectory.

with AutoCAD are stored in the desk\<application>\enu\Textures

This can be re-pathed through the Options Dialog => Files Tab => Texture Map Search Path

New Materials are added to our Current Drawing.

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3

D Scene Setup ighting

mension, 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.

presentation with depth as well as a more real-orld feel.

d a

we

tion.

LLighting adds a new di

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

Lighting adds shadow effects, which creates a

w

Spotlight (allowing for a target direction anhotspot and fall off attribute).

With the combination of any or all of thesecan create lighting compositions that, at the least, infer to a real world situa

Light objects in the drawing will be represented by a block, which is inserted when the new light is created.

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Light Dialogs he Light Dialog gives us options to create new Lights and to control the Ambient light intensity

ights

Drawing

Modify

ight

Select a Light ing

e list

New

Set Ambient Light Intensity

Set Ambient Light Color

Tand color.

Ambient light provides constant illumination in the model.

existing Lights

nList of Li Current

Delete an existing L

th

in the drawto display in

Select and Create a

Light

We can then modify an individual Light’s position, and in the case of a Spotlight, it’s Target.

e can modify a Light’s color and intensity. With a Spotlight we can modify the Hotspot and Falloff.

Name a Light

Change the ght

position and Show a Light’s position in coordinate values

Modify Hotspot and Falloff for a Spotlight

Turn Shadows On or Off for a Light

W

Additionally we can adjust whether or not a specific Light casts a shadow.

Intensity of a Li

Modify a Light’s

Adjust Light color

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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.

To create a scene we simply select

the View and the Lights (using Ctrl+Select) associated with the Scene.

Create a new Scene

List of saved Scenes Modify an existing Scene

Delete an existing Scene

Name a Scene

Select a View

Select associated lights

In the Render Dialog we can choose the Scene to Render.

Rendering

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Background Options We can choose backgrounds for our renderings based on color or based on imagery.

The Background Dialog c

e the current Model Space display background

ecific colors for our Background and even apply Gradient

ncl

e, BMP, JPG, PCX, TGA, and TIFF files.

his gives us the capability of ld

our

an be accessed from the Render Toolbar or from within the Render Dialog.

By default AutoCAD will usfor renderings.

We can select spfills.

We can use imagery, i

Supported Background imagery formats includ

uding digital photos, for our Backgrounds.

Ttaking a digital photo of a site,for example, and using real-worimagery as a background forrendered model.

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The Background dialog is a simple interface to adjust what our background looks like.

Choose a Solid, Gradient, or an Image Background

Select a file for an Image Background and Adjust Bitmap properties

Select a single color for a Solid Background or adjust Top, Middle, and Bottom colors for a Gradient Background

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.

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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 Email, 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

Launch the Background Dialog

Choose to Render a selection set

View More Options depending on Rendering Type

Select basic Rendering options

Choose a Scene to Render

Choose a Rendering Type

Select a Destination for the Rendering

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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.

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Choose color depth for the output file

Select image options for TGA or Postscript files

Choose Output file type and output file resolution

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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 10.0.

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 www.cadtrainingsolutions.com [email protected] [email protected]

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