Attributes Tutorial

Informations

• Publié par: Phawyar
• Nombre de lectures: 13
• Langue: English

Extrait

ED597A COMPUTERS IN

ENVIRONMENTAL DESIGN

University of Massachusetts Amherst

Department of Landscape Architecture and Regional Planning

Fall 2005

Professor Mark S. Lindhult, FASLA

Office: Room 311 Hills North

e-mail: [e-mail]

TA: Elizabeth Lokocz

[e-mail]

Tutorial - Extracting Attributes from AutoCAD

So far in using AutoCAD you have created geometry: lines, circles, plines, etc... You have also added things such as text and

dimensions. All of these things could easily be done by hand, so what else does CAD have to offer?

As discussed in class, AutoCAD is also a database of information. Most of that database contains the information for

reproducing what you have drawn, but you can also add information that is non-graphical. One of the easiest ways of adding

non-graphical information is to use attributes. An attribute is text or values that can be attached to a block to convey more

information than just the geometry.

Look at the two drawings below for an example:

The first example shows a circle and some lines and arcs that could be anything. The second example shows the same

geometry with the attributes visible so that you see that the pictures show a tree. The attributes describe the tree key, botanical

name, common name and diameter of the proposed tree. You can see that AutoCAD has a useful tool for showing more than

just geometry. This information can then be extracted out of AutoCAD and then used in a spreadsheet or other program which

could generate a Bill of Materials. You can also use custom programs to use them in the CAD drawing.

In this Tutorial you will be creating attributes and attaching them to the computer block that you made previously. Like

everything you do in AutoCAD, there are particular steps involved when you work with attributes.

1.

Define (or create) the attributes.

2.

Create the block with attributes.

3.

Insert the block you will give it the specific information.

4.

Extract the information from AutoCAD and save it as an Excel file for formatting.

5.

Merge the data back into the drawing

Many of the commands that you will be using are tough to remember at first. You may find it easier to use icons (but then

the icons look very similar). Pull down menus are another option, so you can see exactly what the command is that you are

starting.

Command

Keystroke

Icon

Menu

Result

Define an attribute

DDATTDEF / ATT

Draw > Block >Define Attribute Creates an attribute definition

Edit attributes

DDATTE / ATE

Modify> Object> Attrb.> Single

Edits the contents of an existing attribute

Block

Block / Bmake

Draw > Block >Make

Creates a block from separate entities and

attributes.

Display Atts.

ATTDISP

None

None

Hides or shows attributes

Extract Attributes

EATTEXT

Tools > Attribute Extraction...

Extracts attributes using the wizard

Create a simple tree symbol in an AutoCAD drawing.

Begin the Attribute definition command: ATTDEF.

Look at the dialog box to the right. Fill in the Attribute

boxes just like the example. Make sure to check the

constant mode (as shown) and adjust the text height.

Select an insertion point near your tree symbol and hit

OK.

Repeat the ATTDEF command for the Botanical Name

and Common Name of your plant, except instead of

picking a point check off the Align below previous

attribute checkbox.

Repeat ATTDEF one more time for the Size but make

certain that you uncheck the Constant Mode.

TAG

PROMPT

VALUE

KEY

Symbol for plant, usually a two letter abbreviation.

BOTANICAL NAME

Botanical name of your tree

COMMON NAME

Common name of your tree

SIZE

What size is this tree?

XXX

Once all the attributes are created you should have a symbol with the attribute

tags listed next to it.

BLOCK & WBLOCK

Now create a block that includes your four attributes. Start up the BLOCK command. When you are asked for the block

name, give it a name such as T-OctoberGloryRedMaple. For consistency, use TD- for deciduous trees; TO- for ornamental

trees; TC for coniferous trees and S for shrubs at the beginning of the file name and then type the common name. Make certain

that you select the whole symbol and all of the attributes to be part of the block.

Use the center of the tree symbol for your

insertion point!!

To save this block for others to use, you will use the WBLOCK command,

which Writes the block out as an AutoCAD drawing. Simply type

WBLOCK on the command line to get the dialog box shown to the right.

Click on Block as the source and notice that it puts the same name as the file

name. The block already has an insertion point. Save this file in the ED597

folder on the M: drive in the Tree symbols folder.

Now, insert the block and you will get a dialog box where you can enter the

values for the tags. You will be prompted to provide answers to the prompt

that you defined in the attributes. For the tree, the size is the only TAG that

you will be asked to provide an answer.

Command: I INSERT

Specify insertion point or [Scale/X/Y/Z/Rotate/PScale/PX/PY/PZ/

PRotate]: (click)

Enter attribute values

What size is this tree?

<4”>: 3.5”

After inserting the block and answering the prompt, your

block should look like this:

DISPLAYING ATTRIBUTES:

Sometimes you don’t want to

see the attribute values displays (say for plotting). You can

turn them off. This can be done by typing in the command

ATTDISP and then OFF. To turn them back on again, type

ATTDISP and ON. It can’t get much easier.

EXTRACTING ATTRIBUTES

So what can you do with all of this information? A CAD drawing can be used to count how many trees, benches, lamp posts

or other objects a designer is using and export that data to another file for others to use to generate a cost estimate. In our case,

we’re going to use the plants blocks to set up a plant list for our planting plan.

Exporting the data became MUCH

easier in recent versions of AutoCAD

with the EATTEXT (Enhanced Attribute

Extraction) command box appear. Accept

all the defaults in the wizard dialog, hitting

the Next button until you get to this step

(right).

Note that all the attributes are checked

- including ones you don’t want. Hit the

Uncheck All button, then select the ones

you want as shown to the right.

Continue to the next step (right) and click on Alternate View so that

you see a count of how many times each block appears.

Continue until the wizard asks you for a filename and save the data

as a Microsoft Excel (*.xls) file and finish. Click on the box next to

filename to select the directory where the file will go.

OPENING IN EXCEL & INSERTING IN AUTOCAD

Now comes the exciting part. When you finish saving the excel file you can open it up and format the data…. change

the width of the columns so that all text can be read; add bold to the headings; rearrange the columns so that they are

in the proper order

like the example plant

list; select the font you

want; add borders

around the cells; and

any other changes you

wish to make. After

you have finished

formatting the file, save

it in your folder.

In AutoCAD set up your LAYOUT. Making

certain that you are in PAPER space, go to the

Insert

pull-down menu and select

OLE object…

When you see the dialog box to the right, make

certain that you’ve selected Create from File and

then click on Browse to pick your file. After hitting

OK, the plant list will appear in the drawing. Use

the grips to resize it on your drawing.

You now have a drawing with the data revealed!

Assignment

You must create at least five (5) plant symbols (or other objects) that will be used in your Mid-semester project. If you

are in the sophomore studio, coordinate with other students in your class so that you don’t duplicate too many symbols

and can share others so that you can have a wide range of plants to use in your planting plan. All symbols should be

saved in the common Plants folder on the M: drive. Check out the plants in the folder before you create a new symbol to

make certain that the plant hasn’t been made already.

The final components of the project are:

1.

the 5 plant symbols

2.

the excel file

3.

a planting plan drawing with a plant list

4.

a rendered master plan using photoshop

The project:

For those taking a design studio, you must work on your current project and create a planting plan with plant list. For those who

are not in a design studio, you will use the plan handed out on Wednesday in class.