Design. Click. Build.

Working With Materials in SketchUp

Fri, 27 Jun 2008 00:15:16 GMT

So you've drawn your woodworking project in SketchUp and you'd like to make a somewhat realistic picture of it to show your client. That's a good idea but how do you go about making it look right? You've found the wood grain materials library but you're not quite sure what to do with it. Before we take a look at the Materials browser I want to talk a little about components. (There he goes again.)

A component or a group is essentially a collection of geometry inside a wrapper. You can think of it as cellophane wrap around a sandwich. To change the component or group you first need to open that wrapper. When you're finished editing, you close it again by clicking off in space or on some other component or group. When it comes to applying materials, y remember to open the component for editing first. You can apply a material without opening the component/group but it is like spreading mustard on the outside of the cellophane on your sandwich. It might look alright but the mustard insn't on the sandwich.

Now, with that out of the way, lets look at the Materials Browser. I'm working with a PC and although things are similar, they look a bit different on the Mac.

This is the Browser. There's a drop down menu above the material thumbnails. That's where you choose the type of material you're after. You then choose the material by clicking on it. When you move the cursor over the model, it turns into a paint bucket. Clicking on a surface with them apply the material you've chosen to the face. If you want to apply the material to more than one face at a time, preselect those faces before getting the material.

Sometimes you'll find that the grain direction is correct when you apply it to a face. You can edit the direction very quickly. Just right click on the face, choose Texture>Position from the Context Menu.

You'll see the following.

The colored handles give you options for editing the position and shape of the texture swatch. The Creen handle allows you to rotate the material. When you click on it, you get a protractor. the broken line arc around the outside shows the direction you are rotating and it also helps guide your cursor so that you dono't rescale the material at the same time.

There's another option for rotating the material. For that you simply right click again and choose Rotate from the menu. You then choose from 90, 180 or 270 degrees.

You can also make your own wood grain materials if you wish. You'll need an image to import and the better the image, the more realistic the appearance will be. To do this go to File>Import. In the dialog box, choose the image type at the bottom and on the right side choose Use as Texture. Choose the image file and apply it to a face. When you apply it, click on a corner and drag toward the opposite corner. The second click will set the material. At this point you can go into the Materials browser and click on the Edit tab. This is where you can edit the size of the swatch as well as the name and color of it. At the top of the browser, type a name for the material. It'll be applied to the material automatically.

Once you've got the material in your model, you can use on other faces in the model. You can edit the grain direction as needed and so on. If you want that material to be available for other models you need to save it to a library. Click on the little white plus sign on the blcak field in the upper right corner of the dialog box. This opens the secondary Materials window. Set the upper window's drop down menu to In Model and set the lower one to the library in which you wish to save the material. Then click and drag the material in the In Model window and drag it to the lower window.

Do a Google image search to find wood grain images that you can download to use. Keep in mind that the more figured woods won't work as well as the straighter grained stuff. this is especially true when you have larger surfaces to cover. The image file will be of limited coverage so the image will be repeated in a sort of grid on the model. This works fine for wallpaper and those wood grain laminates but as you know, wood grain doesn't repeat in nature. You may need to decide whether to use a woodgrain that matches the wood you plan to use or to pick something a little less exciting.

You can also use images you shoot with your own camera if you like. Work hard to make sure lighting is even and that you have the camera placed square to the board.

There is software available that will help you make a seamless or nearly seamless material from your image. I have had good luck with a freeware program called Texture Viewer but you can also use Photo Shop and other image editing applications.

Now we've got all of that, let's look at a couple of advanced techniques. I've combined them in the following images.

Materials are made up of images. the more materials you apply, the larger the file size. Note that any materials you "try on" will be held in the In Model library and contribute to file size even though you aren't actually using them. You should purge the unused materials from your model.

This turned segmented vessel uses two materials for most of it. the rim at the mouth is a third material. Since the vessel is made up of a large number of faces, I decided to reduce the file size by turning the two major materials into a single file. If I'd just applied the two materials to the vessel I would have had to draw additional lines (creating additional faces) to delineate the different colors. The method I used took was easier than drawing the separate on the vessel, too.

The vessel is a simple Follow Me exercise. I drew it so that it is 12" high at the outside edge of the rim.

To begin, I drew a flat surface. In this case it was 2x12 inches. I drew it laying on the ground plane but it doesn't matter as long as the edges of the face are parallel to two axes. I drew the triangle and diamond pattern and painted it with the two wood grain materials. I selected all of it and then copied (Ctrl+Move) it 14 times to make a 12 x 30 surface with the pattern on it. I set the Camera to Parallel Projection and the view to Top. Then I used Zoom Extents to fill the drawing window.

I exported a JPG of this view and then in Google Picasa, I cropped the image tight around the edges of the pattern. The cropped image was saved and imported into the SketchUp model of the turned vessel. Before importing it I drew a vertical face that was 12 inches high and 30 inches long; the same as the original pattern. I used 30 inches because I made the vessel 10 inches in diameter. It's circumference then is roughly 30". (31.4159" to be a little more accurate.)

Next, right click on the material and, from the Context menu, choose Texture>Projected.

Then in the Materials Browser, click on the eye dropper.

Then click on the textured face.

The cursor will turn into the Paint Bucket tool. Click on the vessel.

Obviously the texture needs a little help. This is where a handy plugin written by a fellow whose pseudonym is Whaat come into play. I've posted it at the top of this blog entry. Install the file in your Plugins folder. Make sure it has the extension rb. Then open SketchUp.

Right click on the face of the vessel and from the Context menu choose UV Tools>Cylindrical Map. the material will look like this:

At this point you can delete the flat face. You might notice that I saved the pattern in my Wood library. It is done as I described above. I added a walnut colored material to the rim and since the mouth of the vessel is open, I painted the inside of it black. As you can see I have used only three materials in this model and I've avoided a bunch of extra geometric entities. Since I kept file size lower using these techniques, I could have gotten away with using more line segments for the curves resulting in a smoother shape. I didn't for this example but the option was there.

As always, if you have any questions, please feel free to ask via a comment or by e-mail.

Dave

Extending SketchUp's Abilities

Sun, 30 Dec 2007 21:48:34 GMT

As SketchUp comes "out of the box", it has an amazing range of capabilities. You can draw just about anything you'd like through the use of the exisiting tools. The functionality of SketchUp can be extended though through the addition of plugins. Plugins are files written in a programming language called Ruby. There are all sorts of plugins available. Some are free while others are commercially available. I have collected a large number of them but there are really only a few that I use on a regular basis. I thought I'd write about those. They are listed in alphabetical order.

Plugin files, or ruby scripts as they are sometimes referred to, come with either .rb or .rbs as the file extension. SketchUp comes with some .rb files and these should be left where they are. If you download plugins to use in SketchUp, always save them in the Plugins directory. Some plugins require other .rb files to be functional. Usually the sources for these files will list the additional required plugins. If there are a number of required files for a plugin, the collection of files will be put together into a ZIP file. In those cases you would normally unzip the files into the Plugins folder.

Before bothering with the Plugins, open SketchUp and got to Preferences>Extensions. This is under window in the PC version and under SketchUp in the Mac version. Check the check boxes. Close SketchUp. The plugins will automatically load when SketchUp is opened. Don't go overboard adding plugins. Each one has to load when you start SketchUp. With a large number of plugins in the folder, start up can become a pretty lengthy process.

Applyto.rb This script by Rick Wilson makes it easy to get a component definition from one component and then apply it to other components. This can be a useful way to make component instances be related. It's especially useful when you've forgtten to make like parts related components. Note that only components have definitions. This script does not work on groups or other geometry. You'll find this in the Plugins folder.

Arcs.rb is Didier Bur's tool which adds versatility to the way arcs can be drawn. The standard method involves choosing the end points and the bulge distance. With Arcs.rb you can choose three points through which the arc needs to pass or you can choose the center point and the end points. This one will be found under the Draw menu.

Bezier.rb and BezierSplines make it easy to draw curves that aren't circular. BezierSplines adds several methods for drawing these curves and includes a toolbar to make accessing it easy. Bezier.rb puts its menu entry in the Draw menu.

DeleteCoplanarEdges.rb erases the coplanar edges in a selection. Often when drawing complex geometry it is easy to end up with lines that divide faces where you don't want them divided. This script makes quick work of getting rid of those lines. This will appear in the Context menu

PipeAlongPath.rb and its cousin TubeAlongPath.rb both of which were written by a fellow who goes by TIG,are handy for drawing things such as your dust collector piping layout. They operate somewhat like Follow Me although you don't get to drawn the profile. PipeAlongPath takes inputs for both outside and inside diameters while TubeAlongPath only draws the outside. In both cases you can select the number of segments used for the profile. A word of caution with this one. You can quickly bloat your file size and thus reduce performance by running these scripts. Think about the number of segments used in the path as well as the number of segments used for the pipe or tube. Also consider which script you really need for the application. You probably don't need the inside wall of the piping for your dust collection system but using PipeAlongPath will essentially double the entity count for it. these are found in Plugins

PurgeAll.rb also by TIG is probably the most used plugin on my computers. It quickly purges the SKP file of unused components, materials, styles, layers and scenes. Each of the dialog boxes for these have a Purge Unused function. This plugin does what that function does in just a couple of key strokes. Keep in mind unless you purge nused components, materials, styles, etc. all those things that you tried are still part of the file and add to bloat. Found in Plugins

Weld.rb is another handy script from Rick Wilson. This script will weld together a selected line segments assuming they are contiguous. Use this script on profiles for complex moldings before running Follow Me or Push/Pull to avoid having a lot of edge softening work afterwards. Found in Plugins. Here's an example showing the results of Push/Pull on an extrusion profile that was imported from a CAD file. On the left you can see the results of Push/Pull without welding the segments beforehand. On the right you can see the difference due to running Weld on the profile first. I could have softened all those lines after extruding the profile. It wouldn't have taken that long but suppose that profile had been run around a long, complex path with Folow Me. It would have taken considerably longer than to soften all those edges. Weld is a great work saver.

ZoomSelection.rb by Jim Foltz does exactly what it says. Select an entity in your drawing and choose Zoom Selection from the Camera menu, The view will be zoomed in so your selected entity fills the drawing window. This is different from the Zoom Extents button on the Camera Toolbar.

There are quite a few others but these are the ones I use frequently. You may find others that you'll find useful but be selective. There's no need to add a bunch of files for SketchUp to open if you won't be using them anyway.

Once you've loaded the Plugins, you can assign keyboard shortcuts to them if you wish. You'll find them listed in the Shortcuts dialog box under the menu in which they appear.

Enjoy getting plugged in and Happy New Year!

Dave Richards