Revit Fill Patterns - Part 2

In my previous post on Fill Patterns, I mentioned the Revit Idea about "Double Patterns" being accepted bu Autodesk. Pieter Schiettecatte commented on that post about being surprised Revit could not do this when he first started using Revit. His comment inspired this post (thanks Peter!).

Although we cannot currently use two patterns at the moment, this is a trick to doing it when really needed. Simply combine the two patterns in the text file, creating a new pattern!

Notice, in the sample text file (Test.pat) below I copied the "Concrete" pattern from the Revit.Pat file (comes with Revit) and the "ANSI31" pattern from the Acad.Pat (comes with AutoCAD). I then created a new pattern by simply combining those two patterns to make a third option.

Here is the result in Revit for the sample pattern file and the three options...

To use the custom file in Revit, I clicked the Import button shown in the dialog above and browsed to the test file. There are lots of PAT files for AutoCAD (and Revit, they are just often called Acad patterns online) available via a web search.

• Revit's Revit.pat file is located here: C:\Program Files\Autodesk\Revit 2018\Data
  
• AutoCAD's Acad.pat file is located here: C:\Users\User\AppData\Roaming\Autodesk\AutoCAD 201?\R22.0\enu\Support

One more quick note about the dialog above, when a custom pattern is imported the scale can be set via Import Scale. This is a one-time opportunity, and if you get it wrong you have to delete the pattern and recreate it.

The Import Scale option can be used to create a new pattern without the need to edit the text file. For example, the Revit.pat file comes with a Block 8x8 pattern. If you need a 6.25" x 6.25" running bond tile pattern, just import the block pattern at the scale factor of 0.78125.

It would be nice if the Import Scale option offered and X and Y scale, rather than a just proportional. That would allow almost any tile size to be created quickly. Even better, a built-in feature to graphically edit and create fill patterns within Revit would be wonderful! I am not a big fan of editing text and xml files.

Revit Fill Patterns

In Autodesk Revit, Fill Patterns help define materials on an element's surface and when it is cut; in elevations, 3D views and sections. This post will cover a few thoughts related to this functionality within the software. Specifically, I want to talk about model versus drafting patterns, custom patterns and then a related and "accepted" Revit Idea.

Definition from the Revit.PAT file

• Model vs. Drafting patternsThere are two types of fill patterns in Revit: model and drafting. Model patterns are used to depict real-world elements, such as bricks, shingles, tiles, etc. They are defined and display in model units. An 8x16 inch brick pattern will show exactly 12 courses on an 8-foot-tall wall. A 2-meter-tall wall with a 200x400 mm brick pattern will have 10 courses. Model patterns appear denser at coarser view scales and sparser at finer ones.
  
  Drafting patterns are defined in paper units. If you import the pattern at scale 1 and print at 100% zoom, the pattern's dimensions on paper will be exactly as specified in the file, regardless of view scale. Drafting patterns are used to symbolically denote materials such as steel, concrete, sand, etc.
  
  Drafting patterns are typically defined with smaller numbers than model patterns. Drafting patterns usually contain sizes from 0.04 to 1 inch (1 - 25 mm); model patterns usually contain sizes from 2 to 20 inches (50 - 500 mm). These are guidelines only, not enforced by Revit. Revit's existing restrictions limit the maximum size and density of the patterns, and a review of these restrictions is planned for a future release.

Fill patterns are used to represent materials on a surface. Any AutoCAD hatch pattern can be used by Revit. If you want an AutoCAD pattern to be used as a Model filled region (versus Drafting which changes scale with the View Scale) you have to add ;%TYPE=MODEL to the PAT file as shown below. The “;” symbol at the front rem’s out the line so even AutoCAD could still use the file… however it might be best to copy the ACAD.PAT file to another location specifically for Revit use.

Text used to define a model pattern

You may also see some patterns with ;%TYPE=DRAFTING as shown below, but Revit will assume “drafting: if nothing is specified.

Text used to define a drafting pattern

When creating a “model” pattern, if you try to use the AutoCAD ACAD.PAT file without making any changes, you will get this error.

Error when PAT file contains no model patterns

There are tons of hatch patterns for AutoCAD one can find via the web. If you need something custom you can either edit the PAT text file, or use a Revit add-in like Hatch22 or HatchKit to create it. Or Hatch Manager by GlobalCAD, which requires AutoCAD, but it makes the process very easy. You just draw the hatch pattern you want (see carpet squares example below) and then use this add-in to automatically generate the PAT file. This file can then be imported into Revit.

Update: Dmitry Chubrik, from the Russian BIM2B site, provided another option in the comments: Pattern Maker. Thanks Dmitry! If anyone knows of others, please share.

Custom pattern drawn in AutoCAD

Over in Revit Ideas, there is an idea about fill patterns that received a lot of votes (353 so far); Double patterns. This is a great idea which I voted for and added to the discussion. Even better, this post highlights the value of this mechanism to find out what we, as users, want. Notice Harlan Brumm, Revit Product Manager, replied, indicating this idea was under review. Later Sasha Crotty, Revit Core Product Manager, posted that the idea was accepted, meaning it will be added to the software in a future release (see image below)! I was even contacted by Autodesk to answer a few questions on this topic. Power to the people, go Autodesk!