Monday, December 18, 2017

Revit® Materials - Appearance Images

Here is an older tip I posted on LinkedIn a year and a half ago, and thought I would copy it over to my blog...

When a design team is developing a Revit model and materials are being applied, everyone needs to make sure they understand a few things about the process to ensure success! I want to share a problem that comes up occasionally and discuss the solution.

The Problem
When someone starts a rendering, either locally or in the cloud, Revit will...
display the following warning if any of the Appearance Images (e.g. the jpg image of the brick) are not found.


There are a couple reasons you might see this warning. One reason is that you simply don't have the image file; someone downloaded a family (e.g. a chair from Steelcase) which uses an image file which was not downloaded. The second reason is you don't have access to the file; someone saved the image file to their local drive or you don't have access to a specific network drive.

FYI: Students will also see this problem if they are working on multiple computers; maybe a laptop at home and a desktop in the school computer lab.

The Solution
Solving this problem can be a little tricky--this involves finding the image file, if you even have it, and then figuring out which Revit material uses it.

The image file name does not really help you figure out what Revit material uses it. Note the material could have several image files associated with it, so the material name and appearance image name are not the same.

In the image below we see a material called "Masonry - Brick" uses one of the missing Appearance Images listed in the previous image. Notice the preview swatch is bright red with an exclamation mark symbol indicating the image file cannot be found. Hover your cursor over this area and Revit presents a tool tip showing where it is looking for the file.

FYI: This missing image file will create issues for other programs as well; such as Autodesk Daylighting Analysis, Revizto, Enscape, Showcase, etc.

In this case, someone may have edited an out-of-the-box material and then hit Save-As, not realizing they were saving the file to their local hard drive. This means when anyone other than the person who created the material tries to render or use realistic-mode they will have a problem. Revit does not save a copy of the appearance image file within the family or project file.

In the case of an image file being saved to a local computer, just move it to a shared location on the firm's network. And then...

To select the correct image file in another location, or select something you do have, click the file name listed below the preview area as shown in the image below.

TIP: When searching for materials through Revit's Select File dialog, you can use filters as shown in the image below; the dialog is currently only showing materials containing the word "white".

The image below shows the correct appearance image file selected. We now see the proper preview of the image.

In the case of downloaded content, it would take too much time to repath all the appearance images within materials. In this case we can place all the image files in a shared location and tell Revit to "look here" anytime you cannot find an appearance image file. In the example below we have a few folders containing furniture manufacturer's appearance image files. Each of these folders can contain hundreds of image file files.

TIP: The appearance image files typically need to be downloaded separately from the family file.

When trying to figure out which material uses a missing appearance image file, it may be helpful to Purge unused materials to shorten the list. However, this command should be used with caution to ensure required items are not removed form the project file. The purge command may need to be run up to three times to fully purge all unused materials and assets.


Preventative Medicine
Make sure everyone working with materials knows they should not save image files to their local hard drive and that downloaded content may also have images files that need to be downloaded separately.

These image files can be saved in the project folder, or in a shared network location. I recommend the latter if the material can be used in other projects.