Exercise 1: Getting to Know AutoCAD Map 3D and Data Formats
Thu, 03/24/2011 - 03:37 pm
Parts of the Exercise
Part 1: Hands-On Exercise - work with the software and answer some questions
Goal: (1) Learn a bit about AutoCAD Map 3D (We'll work with this program this week and next week.)
Goal: (2) Explore how the software deals with data formats
Part 2: Exploring Web Formats - prepare and record a briefing on a Web mapping format for your classmates
Goal: (3) Learn about Web mapping formats
Part 3: Peer Learning - interact with your peers by viewing a classmate's briefing and discussing it
Goal: (3) Learn about Web mapping formats
Because you are experienced GIS users, I will not be providing a “cookbook” to guide you in working with this or any of the software we use. Instead, we’ll use the materials provided with the product. Our “Guidebook” for the first part will be the AutoCAD Tutorial, User Guide and Help. We won't follow the tutorial to the letter, nor complete the entire thing. I'll note which parts to do and what to skip. You are welcome to do more of the tutorial than we do in the exercises, but it's not required.
I suggest you think of the tutorial, User Guide, Help, as references to guide you in figuring out the program. Have one or both open as you work through the hands on part of this exercise.
Finally, a word about the AutoCAD Map 3D. AutoCAD Map 3D is built on AutoCAD, so there are many sets of tools and menus. If you’ve not worked with CAD, it may seem somewhat complex, but I’m confident that between the documentation, tutorial, your classmates' input and the Q&A on the Autodesk Student website [students.autodesk.com/], we can all find our way.
Note: The questions highlighted below for Part 1 are listed separately on the next page of this lesson so that they can be easily copied and pasted into a word processing document.
Get Your Bearings
- Start up the software. When given the choice, choose the “Task-based Ribbon” workspace. That provides menus more suited to our work. Dismiss the "New features workshop" dialog.
- Open up the Tutorial from the Help menu. The help is in the top right of the screen (see graphic). Click on the down arrow to open the menu, then select Learning Resources. That will open a dialog box with many resources, including the Tutorial. Alternatively, you can find the tutorial as a PDF in the folder where you installed AutoCAD Map 3d, on my machine it's here: C:\installs\autodesk\2010\en-US\SetupRes\Docs\map_tutorials.pdf
- In first section, Introducing AutoCAD Map 3D , read through and do the first three lessons.
- In the Get Ready section follow the directions about copying the tutorial data to the “My Documents” area of your hard drive and create a folder for your drawings.
- Follow the Taking a Quick Tour of AutoCAD Map 3D and open up SAMPLEMAP.DWG Be sure to set up the alias (see graphic) – that just tells the software where to look for data.
- In Get Started: Create a new map. Set coordinate system. Connect to Roads.shp. Style the roads. Save the drawing with yourname.dwg in the folder you created to hold your drawings.
Question 1: You used the OSGeo FDO Provider for SHP to connect to the shape file data. Explain what FDO is in your own words. What are its strengths/limitations for accessing data formats? (You might want to use the Help/User Guide/etc. to explore this question.)
- Jump to the next section of the Tutorial: Building a Map. Start with Lesson 1: Use Multiple Sources. We’ll be doing each of the first five exercises, but first, just worry about Ex 1: Drag and drop a source file.
- Ex 1.Open the drawing you created, the one you named after yourself (or use it if it's still open). Go to WINDOWS EXPLORER and find CITYBOUNDARY.SDF. Drag and drop CITYBOUNDARY.SDF on to the task pane, on the display layer area. Once you see it on the map, return to WINDOWS EXPLORER and try to open CITYBOUNDARY.SDF in a text editor (WordPad or NotePad will work). If it's in use by another application, try to remove it from use and try again to open it in an editor. (Hint: If you have trouble removing the file from use, remember that you did two things to add the shapefile above, first you created a connection, then you added the data to the map. BOTH must be "undone" to free up the file.) Look at the SDF file in the editor.
Question 2: What can you say about the format SDF from opening the file and exploring Help/Docs/Etc? Into which of the categories noted in the course materials does it fit? What are its strengths? Weaknesses?
- Ex 2. Attach a drawing file, COUNTIES.DWG (careful, this is different than connecting to a data source!) to your drawing.
- Ex 3. query back the boundary of Shasta County. Once you see it onscreen, convince yourself using the software's interface that the DWG file is attached.
Question 3: How did you convince yourself that the DWG is attached? (Use a graphic if need.) Explain the differences between how AutoCAD Map 3D accesses feature data formats (such as shapefiles and SDF files) and drawing data (DWGs). In particular, what do you have to do to draw the graphics on the screen?
- Ex 4. Add in PARCELS.SDF.
- Ex 5. Add imagery. Even a set of images this small is tiled to speed things up.
- Ex 6. Re-order the drawing order.
Question 4: Search the Web to identify a Web mapping app that uses tiling. Include a screen shot showing tiling in action, that is, catch the app in the act of rendering its tiles!
- Skip up to Lesson 6: Edit Objects in the Use Multiple Sources Tutorial (the same one you were just in).
Don't worry about finding a particular parcel to edit - just use any one you like. Read up on check in/out in the help and be sure to check in your edit after it's complete. Note that some formats, including SDF, which we just edited, do not support locking in multi-user environments.
Question 5: The ability to edit in a multi-user environment with full support for locking of features would be one reason to select one data format over another for data storage. What other factors would you consider in selecting a data format? Based on the type of work you do (or hope to do) prioritize the list (including multi-user editing) from most important feature to least. Explain why #1 is at the top of the list.
That ends our work with the tutorial, so this is a good place to take a break, if needed.
Creating New Data Sources, Schemas and Actual Data
Now it's time to create some new data and write it out to different data formats. This will give you a sense of how AutoCAD Map 3D manages the internal structure of data it creates in different data formats. We will be working with three data formats: shapefiles, SDF files, and AutoCAD DWG files. We will be creating feature data and drawing data.
- Open up the the User Guide from the help menu. Alternatively, it's in the folder where you installed AutoCAD Map 3D, on my machine: C:\installs\autodesk\2010\en-US\SetupRes\Docs\map_ug.pdf I find the PDF far easier to use since I can tell you what pages are relevant.
- Read Managing Data in the User Guide (pp 509-510, 546-551) to learn about Creating Schemas (the structure of the data in your data store) . Feel free to read the parts about connecting to databases if you like, though we'll not be working with those.
- Read Creating a Datastore on page 537, then jump to To create an SDF or SHP Data Store on page 540. Details on are on pages 509-510. From reading this material you should get the idea that the process for creating SDF and shape files includes (1) creating the physical file(s) on your hard drive and creating a corresponding schema.
- Our goal is to create data with points, lines and polygons in shapefiles and and SDF file, and later to do the same in a DWG file. Take a moment to think up feature types for each (hydrants, streets, ponds would work, for example, but think up your own). You'll include two user generated properties (attributes) for each feature type. For hydrants, those might be date of installation and ID number. Think those up, too.
- Create a folder in the Tutorial folder for all your shapefiles. Call it "shapefiles" if you like. Start up AutoCAD Map 3D with a new drawing. Set the coordinate system - pick your local one if you like, or choose the one from the tutorial (CA-I); just be sure to use the same one throughout! (Remember how to set the coordinate system for a drawing? Use Map Explorer and right click on the current drawing to pull up the coordinate system dialog.) Create three shapefile stores, all in the same coordinate system - one for point, line and polygon features and store their files in the folder you just created. Create a schema for each. (User Guide page 540 and/or this video will guide you.) Be sure to assign a geometry type since shapefiles can have only one. To do so: Highlight the geometry property in the schema editor and examine the Data Attributes. The one called "Geometric types" provides the three options - just with names that might be different from those you may commonly use. Once the Geometry is set, add two user generated properties and set their data attributes (should they be text? integer? etc. - and of what length?).
- Find your feature types in Display Manager (they are automatically added when you create them) and right click on the one set up for point features (it'd be hydrants, in my example). Choose Create... and click on a location for a new point. Update its properties. Add two more point features. Do not forget to "check in" your new features by selecting them and right clicking for a shortcut menu, then choosing "Check in Features." If you don't do that, the features will not be added to the new shapefile.
- Create, add properties and check in features for the line and polygon layers, creating three of each type.
Question 6: Besides the features being added to the data source, one other thing changes when you "Check in" the new features. What's that? Hint: check the data table.
Creating an SDF File
- Create one SDF file with a schema that includes three feature types: one each for point, line and polygon. Save it in a location where you can find it, perhaps in a folder called SDF File. By default, the first feature type will be assigned a geometry and FeatID property. The former details what geometry is possible for that feature type and the latter acts as a unique identifier. You'll need to modify the geometry for that first one to reflect whether it's point, line or polygon, then add the two properties just as we did above. For the other two feature types, you'll need to create geometry properties and unique id properties, as well as the other two properties you made up. Set the geometry attribute to be point, curve, or surface. Set the property you create for the unique ID to be INT32 and be autogenerated. Be sure to select in the feature type's main window which property will be the user id otherwise one won't be assigned and no features can be added! (see graphic) Create three point, three line and three polygon features in the SDF file. Again, don't forget to "check in" the new features.
- No need to save this drawing since all we did was use it to create the new data stores. All the data we created is now safe and sound (we hope!) in the shapefiles and SDF file.
Creating DWG Files
- When we created the features for the shape and SDF files, we used special AutoCAD Map 3D "Create" commands to do it. That allowed AutoCAD Map 3D, among other things, to know what type of feature we intended to create (a hydrant, road, or pond). We didn't use basic AutoCAD commands to put in points or draw lines. That's because creating spatial features is different from creating AutoCAD entities. Now we are going to create some AutoCAD entities to use in conjunction with the two feature data stores we created.
- Create a new drawing called drawing_data.dwg. ("New" is in the "M" menu, top left.) Store it in the tutorial directory. Give it the same coordinate system as your other data stores. (Use Map Explorer tab and right click on the current drawing to pull up the coordinate system dialog.) Use AutoCAD's layer properties command (see graphic) to pop up a dialog box to create three layers in the drawing. You'll need to right click in the right-hand empty white window to pull up a shortcut menu with an option for "new layer."
- Call the layers "flagpole," "railroad" and "boundary" and give each a different color. (Yes, those are for points, line and polygons.) Make flagpole the current layer by double clicking it. The current layer is marked with a green check mark – it's the layer on which any new drawing entities will be placed (see graphic).
- Connect to the SDF data store you created above - the one with points, lines and polygons in it. Choose View, and Zoom Extents (see graphic) to see all the features. Use the AutoCAD "point" command (from the top Create menu, see graphic) to populate three flagpoles across the drawing. You should see some tiny dots in the color of the flagpole layer. Use the layer command to set the current layer to railroad. Use the polyline command (also from the top Create menu) to draw a railroad across your area. A polyline is a line with many straight or curved segments in AutoCAD lingo. Change the current layer to boundary. Use a polygon command (see graphic) to draw the boundary around your area so that all the SDF- and DWG-sourced features fit inside. You can use View/Zoom Out to see them all, if needed, before you begin to draw the boundary.
- Once you've drawn the boundary, it will hide all the features below it. Use the Layer command one more time to set the current layer to railroad and turn the boundary layer off (by clicking on the "light bulb" associated with that layer in the dialog box). Save the drawing. Close the drawing.
Bringing Back the Data We Created
- Now, let's query back all of those data types and see what can be done with them. Open a new drawing; set its coordinate system to match that of the data sources you created. Have a look at the Layers dialog to see what layers are available. (Should be just one - layer 0, the default). Connect to the shapefile data sources you created (use the folder option to get them all at once!) and add them to the map. Do the same for the SDF data set. Attach and then query in, using the DRAW, not the PREVIEW option, all the data from dwg_data.dwg. (A location query with "all" option will do the trick (see graphic).
- Now, let's explore what happened while these features/drawing entities were added. First, revisit the Layer dialog. Anything new? Now, let's look at the differences between the feature data and drawing data. Click on one of the feature data elements in the drawing (from the shapefile or SDF sources). Right click for a shortcut menu. Note the "Check out Feature" and "Show Data Table" options are there. Choose "Show Table Data" and you'll see the feature's attributes. Now, click on a drawing entity, such as a railroad polyline.
Question 7: Are the same options there? What different options are available for the drawing entity that are not there for the feature? Choose the properties pick from the shortcut menu. What information that you set up in the drawing is available, say for querying, or for turning the drawing data into feature data? What are the potential benefits and challenges of working with both feature data and drawing data in the AutoCAD Map 3D environment?
You have been randomly assigned in an e-mail one of the following (growing list!) of Web mapping formats/environments to explore.
- Scalable Vector Graphics (SVG) format
Presentation Assignment: You'll each present a briefing of five minutes or less on a Web mapping format. You'll use Jing to capture the audio and video. The first part of the presentation will answer the questions below. The second part will include a demo of the format in use in a Web mapping application. Some of these formats are commonly used in other types of applications, but only mapping one are appropriate here! You can use PowerPoint or another display mechanism for the discussion of the questions, if you like, then add a video of the demo.
- Do your research to learn about the format. Find a complete (not beta, not sample) Web Mapping application that uses the format. It may take some effort to find the format in use on a website; if you need help, let me know.
- Rehearse the presentation. Review the Course Orientation "Using Jing Project" page for reminders on how to use Jing. Record the presentation.
- Post the link to your video in a new thread below.
Questions to be answered about the format in your briefing:
- Open or proprietary? (not sure what these mean? - review the lesson!)
- Who created the format and why?
- Give examples of GIS products that read and write the format.
- Is it a standard? Whose?
- Humanly readable or coded?
- Show and explain some sample code (if humanly readable)
- Does the format have any special qualities/capabilities/uses?
Things to highlight in the demo portion of your briefing:
- Does it require a browser plug-in? Is that an issue?
- What particular features of the format does the application use/reveal/take advantage of?
- Why do you think this format was selected for this application?
- Is there something in this application the format allows that you've not seen before?
This is your chance to learn from and interact with your peers. Select one of the presentations to watch and on which to comment. Watch it (as many times as you like!) and then offer a comment in the thread below. Let's aim to have everyone review a different video, so if you see a video already has a review, choose another one!
Comment Assignment: Visit the demoed site and view the video. Then, in no more than 500 words tackle these questions comment:
- Based on what you've learned, what types of applications should use it?
- Have you seen it in use before? Where?
- How does it compare to the format you explored?
I encourage you to do this part of exercise just after the assignment is due, however, I will not grade these comments until the end of week five.
Submitting the Exercise (all parts)
- Part 1: Answers to Questions
- Go to the Lesson 1 folder in ANGEL.
- Click on the Lesson 1: Exercise 1 Drop Box and follow the directions from there to submit your answers in the format of a Word document. Please use the naming convention ex1_yourlastname.doc
- Part 2: Record your presentation, and post the name and URL of the demoed site, along with a link to your Jing video in a new thread below.
- Part 3: Post your Peer Learning comment in the thread where the presentation link was posted below.
All submission dates are listed on the Course Calendar in ANGEL.
Here is how the assignment will be graded.
7 questions x 3 points each
Part 3: Couch Critic Comment
|Total for Exercise 1
Part 1: 7 Questions x 3 points each = Total of 21 points
|For each question
|| Points to be earned
|No answer, incorrect||0|
|Partial response in acceptable form||1, 2,|
|All of question(s) answered in well articulated form within length guidelines||3|
|Total for each question||3
Part 2: 1 Presentation = 15
Points to be earned
7 questions answered
demo highlighting format
Presentation organization, smoothness, effective graphics/demo
7 questions answered
demo highlighting format
Presentation organization, smoothness, effective graphics/demo
Part 3: Peer Learning Comment
Please post all questions regarding the Exercise below in the comments field. You may be able to help your peers out, or you may see the same question already asked. If need be, don't hesitate to get in touch with me via phone or email ASAP if you have any additional questions about this exercise. I would not recommend waiting until the last minute to contact me, as I cannot guarantee a response before the exercise deadline.