Display Priorities of Solid Fill in Revit Materials

Back in Revit 2012 Autodesk changed the way materials work - so that they had separate graphics and appearance properties.  This was the start of much confusion for many users - and still to this day it catches people out.  You know the drill:  duplicate a material;  change its appearance properties and suddenly a hundred other materials change too . . . .

Well, I am not going to address that issue directly.  Instead I want to look at a more subtle confusion that some users encounter:  Exactly how do the different material properties display in each 'Visual Style' - it will not always be what you might expect or consider to be logical

Material Properties

In order to analyse this issue we start with two very simple material definition examples, applied to two elements in a Revit project:

Material 1 - Demo Generic

• Light grey shading 
• Light Blue appearance (different colour to shading)
• no surface patterns
  

Material 2 - Demo Green

• Light green shading and appearance;  
• no surface patterns
  

Visual Styles

These materials display as expected in the various 'Visual Styles' in Revit - because we know that the graphic 'Shading' colour property matches the 'Appearance' colour property in material #2 but not in #1 

Material #1 on left,              Material #2 on right

Hidden Line Visual Style

Shaded Visual Style

Consistent Colours Visual Style

The colour displayed for material #1 (left) in Realistic and Ray Trace visual styles is different to shaded and consistent colours because the material properties do not match - this is to be expected.

Realistic Visual Style

Ray trace Visual Style

Material #1 on left,              Material #2 on right

Lighting

These views are lit with default sun and lighting settings (ie. light source over the right shoulder of the viewer)

 

Use Render Appearance

One thing that users often forget to address is consistency between the 'Graphics' and 'Appearance' colours.  If the colours are dramatically different, then materials look completely wrong, particularly in 'Shaded' views.

There is a quick and easy way to deal with this - it is the 'Use Render Appearance' checkbox to make sure the shaded colour matches the appearance colour.

 

This property can be used as a one-off operation - ie, tick the box to change the colour, then untick it.

Or you can just leave it ticked if you want the shading to update when the appearance property might change in the future.

• NB.  Make sure that the appearance colour is correct first - as there is no 'Undo' so you might lose a shading colour definition.

• Do not use this method if the shading colour is correct but appearance wrong
  

Surface Patterns in Materials

When you add surface patterns to materials is where things get more complicated . . .

We will make two more materials, based on the light green shaded material - these will use the same light green 'Appearance' (unchanged).

Material 3 - Demo Green Line Hatching

• Light green shading 
• Light green appearance;  
• Line Cross-Hatching foreground surface pattern

Material 4 - Demo Green Solid Hatching

• Light green shading 
• Light green appearance;  
• Line Solid Fill foreground surface pattern

Visual Styles

Hidden Line

• Cross-hatch pattern is displayed as you might expect
• Solid fill displays with solid colour - but without any lighting effects

Material #3 on left,              Material #4 on right

Hidden Line Visual Style

Shaded

• Cross-hatch pattern is displayed on top of the shading colour
  
• Solid fill displays replaces the shading colour - it is completely obscured -  this can be confusing if the user has not studied the material properties carefully
  

Shaded Visual Style

Consistent Colours Visual Style

Realistic (and Ray Trace)

• Cross-hatch pattern are not displayed at all - unless a hatching pattern is defined within the material appearance (not a simple thing to achieve)
  
• Appearance Colour replaces the Solid fill colour -  this is the reverse of what happens in a Shaded visual style - so it can be confusing
  

Realistic Visual Style

Background Hatching

Just for the record, here is what happens with background hatching - it follows the same rules as Foreground hatching.  [NB. This capability was added in Revit v2019]

Material 5 - Demo Green Line Background Hatching

• Light green shading 
• Light green appearance;  
• No foreground hatching surface pattern
• Line Cross-Hatching background surface pattern

Material 6 - Demo Green Line Foreground & Solid Background Hatching

• Light green shading 
• Light green appearance;  
• Line Cross-Hatching foreground hatching surface pattern
• Solid Fill background surface pattern

Visual Styles Materials 5 & 6

Material #5 on left,              Material #6 on right

Hidden Line

Shaded

Consistent Colours

Realistic

Conclusion

Solid Fill surface patterns are the one part of this Visual Style issue that cause display inconsistencies.

You may have good reasons for using Solid Fill surface patterns as part of a material definition - in which case go for it.  Otherwise, they are to be used with caution in normal Revit use.

Another approach to avoid the inconsistencies would be to make sure the appearance, shading and solid fill colours all match up.

Don't forget to check how many materials are sharing the Appearance asset before you change it - it is the number above the hand on the Appearance tab.

Stair Section Detail Level in Revit

Here is yet another problem with Revit Stairs that really needs to be fixed by Autodesk:  

The view 'Detail Level' display in section is not consistent between walls, floors and stairs (not to mention ramps!):

View Detail Level

When a view is set to Medium or Fine detail level, sections of most categories display the correct materials:

When the View detail level is set to 'Coarse', the cut hatching display of some elements is overridden by the Type properties 'Coarse Scale Fill Pattern'

This capability is available only for certain categories - meaning that the display of stairs is pretty hopeless at Coarse scale

 

Workarounds

What to do about this?  There are several possible ways to resolve this lack in Revit, but none is very good!

Visibility Graphics

You can over-ride the cut pattern of stairs - but this requires several steps (excuse the pun) on top of just changing one View Detail Level setting:

Due to the fiddly nature of changing this in the view (similar settings may need to be applied to other categories), you would certainly need to include this as part of a View Template - so it could be applied or removed at the flick of a switch.

Filters

You could also try using a View Filter, as it could potentially be applied to multiple categories

This has an advantage in that it is more "discoverable" than searching through all the category overrides - unless you have a gazillion filters applied!

Another advantage in Revit 2021 is the ability to "Enable" or "Disable" the filter without losing the override settings - a very useful new enhancement for Filters.

Downsides

The View Detail Level is very easy to switch on/off - and it affects all categories that have the built-in Coarse Scale override capability.  If you set the view back to Medium, the 'by category' cut pattern overrides get left behind - so you would need another operation to remove those (hence the need to use View Templates).

Another problem with the Visibility Graphics workarounds is what happens when you choose anything other than black solid fill as your hatching override:

If you make it grey . . .

 

The Stairs will show the joint lines between different materials - you may or may not want this, but it is clearly different behaviour to the Coarse Detail Level control that hides the material join lines and treats it as one material, for a nice clean look.

Of course, this is not helped by the inability to join walls/floors to Stairs !!  You still get the joint lines between those.  Refer to Stair Joint Lines

The Worst Workaround

Filled Regions are extremely useful for patching up Revit's inadequacies, but they are not popular with BIM & Model Managers because they cause so many other problems as soon as a model changes.

Filled Regions allow you to make the hatching look exactly how you want, because they allow some of their edges to be "Invisible Lines" - thus they can appear to join with adjacent "real' cut hatching.

Filled regions are placed per view, so if you have multiple sections cutting through the same or similar parts of the model you may end up with many filled regions.

One possible method to manage that problem is to include them in 'Detail Groups' - but they are also problematic to manage, not to mention a major shortcoming of really slowing down your Revit model if you have too many of them.

Conclusion

Whichever workaround you use the most important thing to do is to follow company standard procedures - and be consistent.  Agree with your workmates on which dodgy workaround to use, and stick to it.  This will make it so much easier to come back to make changes when the model is updated.

Architectural Ceiling Plan Hidden Categories in Revit

A while back, someone asked me why some model elements remained visible when they turned off ALL Model categories in Visibility Graphics.

The list of categories that show on the Visibility/Graphic dialog box varies depending on the Discipline filters applied to the dialog box. If you are preparing a set of architectural reflected ceiling plans, you may want to show lights, sprinklers, security etc. However, not all relevant categories are shown if you only have ‘architecture’ ticked.

Watch out for hidden categories in this situation. Each user may have different discipline filters applied on their computer (it is per user in Revit, not per view).

This means that some MEP categories may not be shown in the Visibility/Graphic list – therefore the user will not be able to show/hide or override those categories.

If the user has only the Architecture discipline showing, then clicks on ‘All’, it does not include the hidden MEP categories, including:

• Data devices
• Fire Alarm devices
• Nurse Call Devices
• Security Devices
• Sprinklers
• Telephone Devices

I have encountered situations where frustrated users have turned off all categories, and wondered why the sprinklers remain on.  For this reason I recommend that architects should consider using only  the following categories for Ceiling and Electrical fixtures in their libraries - for architectural Revit models:

• Electrical fixtures
• Lighting Fixtures
• Mechanical Equipment
• Specialty Equipment 

Architecture Discipline Only

However, for multi-disciplinary Revit models you probably need to stick with the correct categories - obviously MEP engineers should use the correct categories for their models, because they have specific behaviour that is important to them.  In the case of separate, linked MEP models, the services engineers may be modelling their own fixtures, and using the architectral model just for coordinating ceiling fixture locations.

All Disciplines

For architects working in multi-disciplinary models, where you do need to use the correct categories for all fixtures, then you need to educate your staff about changing the filter list to show all relevant disciplines. 

What a pity that we don't have all the categories that we need - Signage for example (amongst many others missing).  However we do have at least one redundant category: Roads - we'd like to be able to use it but we have no tools to model roads with.