Why Can’t I Suppress the Rendering?

Often when using ElumTools, you won’t be interested in a rendering and will only need the point-by-point illuminance values, and perhaps the associated statistics (avg, max, min, ratios, etc.).  A common question we get is if there is a way to suppress the rendering and have ElumTools only return the numerical results when calculating (usually in the interest of faster calculation times).

The answer to this question is no.  But it isn’t because we neglected to add the feature :).  ElumTools, like AGi32, uses a process called radiosity to consider all the interreflected light and its contribution to the point-by-point results.  With radiosity, the math to produce the calculation point values is identical to the math required to produce the rendering.  In other words, the point-by-points are a by product of the rendering.  So, were the option to suppress the renderings given, the calculation time would remain roughly the same.

There are, however, some things you can do to speed things up, particularly if you are daring enough to compromise on calculation accuracy.  This help article contains some handy tips. These can be particularly useful during design iterations when only approximate computations are required.  Then the settings can always be ratcheted up for final deliverables, when greater accuracy is needed.   Layout assistant can also be a useful “quick calc” tool to get a rough idea of fixture quantities, early in the design process.

Layout Assistant as a “Quick Calc” tool

The Layout Assistant is an easy avenue to quickly estimate average illuminance levels and make adjustments to luminaire quantities as needed to meet your criteria.  To start, simply enter the quantity of luminaires you plan to use.  Layout Assistant will immediately display an average illuminance estimate for the quantity entered, as well estimates for plus or minus 1 luminaire.  layout-assistant-quick-calc-1

The estimation algorithm used to produce the estimate is significantly more powerful and accurate than the Zonal Cavity based methodology built into Revit.  Layout assistant employs the same radiosity engine used by the calculate commands , and estimates results quickly by applying a very coarse mesh to the environment.

There are many options in the Layout Assistant dialog to tinker with the luminaire positions.  When you’re happy with your layout, place the luminaires in the Revit model by clicking “ok”. If you want more confidence in the illuminance estimate first, perform a full calculation using the “Calculate” button.

New Commands Available in 2017.3, 2016.7, 2015.10!

The latest ElumTools update includes dramatic new capabilities to use 3D views to sort the portions of the model you wish to compute. You can now compute the Active view, or compute any number of separate 3D views using the Calculate Multiple Views command. These commands allow easy and intuitive control over which elements are calculated. This is particularly handy for phased projects and projects employing multiple Design Options.


The Calculate Views functionality paves the way for another new command, Create Daylighting Views which will allow you to stratify your model into interior and exterior geometry thereby solving the old problem of exterior geometry in daylight calculations.  Now exterior shading devices and adjacent structures can be considered with ease for Daylight Analysis.


In addition to the new calculation functionality, the latest ElumTools update contains many other Enhancements and Bug Fixes, improving both usability and performance of existing ElumTools features.

Calculation Points on Stairs

Stairs present an interesting challenge when placing calculation points in ElumTools.  Adding area based points, such as space points or region points, isn’t a good option because the calculation grid will be flat.  Planar face points also present a challenge as they would necessitate adding a separate calculation grid to each tread of the stair case (flexible but tedious).  These challenges make stairs a good candidate for line based calculation points.  Here’s a sample work flow.

  1. Create a Reference Plane following the profile of the stairs.  This will typically be easiest in a Section View.
  2. Draw a model line on the sloped reference plane.  This is typically easiest in a Plan View.
  3. Add line-based calculation points to the newly created model line, and use offset lines to create the grid.

Typically for stairs, you will want to define a tight point spacing to be used along the run of the calculation line. Offset lines can then be used to place points along the horizontal span of each tread.

Screen Shot 4

When calculating the stairwell, you will see the calculation points follow the profile of the stairs based on the spacing specified in the Add Points dialog.  Some iteration may be required to get points located in the necessary locations, particularly for complex staircases.  But by using line based points you will save the time of having to locate a separate grid on each tread.

Screen Shot 5



Masking Calculation Points

ElumTools now allows calculation points to be associated with both Filled Regions and Areas.  That’s right. It is no longer a requirement that the calculation points be associated with the Room or Space being calculated.  Instead, the calculation points grid can have any shape. This provides an easy mechanism to exclude calculation points from portions of the grid that do not require analysis.

This flexibility can be useful in situations where large equipment or furniture is present.   An easy work flow for this situation is to,

  1. Create a Filled Region or Masking Region, leaving a hole for the equipment.
  2. Add Calculation Points to the Region using the ElumTools command.
  3. Calculate the Room as usual. ElumTools will place points only within the boundary of the Region, while still calculating every element in the Room.  This ensures that all equipment will be properly considered for the Calculation, but calculation statistics will not be skewed due to objects occluding light reaching the calculation work plane.




Calculation Point Family Management

Every time a calculation grid is added to the project, ElumTools places an instance of the ElumTools Calculation Points Family into the Revit model.  This can be a useful visual indicator to determine where calculation points have been placed.  However, it is sometimes convenient to hide the Calculation Points Family.  This can be done using the Toggle Calc Points Family Visibility command as shown below.


The main caveat is the command will not hide the family if the active view has a View Template applied. You are instead greeted with the tool tip below and the Calculation Points Family remains visible.


What to do? Any View Template can be modified to hide the Calculation Points Family. The family is in its own subcategory and can be hidden, just as any other subcategory can be hidden in Revit.


Now suppose you’d like to hide the Generic Models category, but leave the ElumTools Calculation Points subcategory visible.  This can easily be accomplished by a few clicks on the Filters Tab of the Visibility/Graphics dialog.

Step 1. Enable Generic Models in Visibility/Graphics.


Step 2. Create a new Filter.

Create a Filter that hides all Generic Model families whose Family Name does not contain the string “ElumTools”.  This methodology can be applied to either a View Template, or the Visibility Graphics settings of any View in the Project.

Filter Dialog2

Duplicate Linked Models – a cautionary tale

Revit has an interesting feature that allows you to load duplicate linked models with the same name.  This can be useful in some situations but is often a consequence of a simple oversight.  This can sometimes cause problems, and is best understood through a visual example.

Design Tree

This can lead to problems in many parts of Revit and often isn’t a recommended workflow. One such problem you may encounter when using ElumTools is the inability to correctly specify Material Mapping settings. See below.


One solution to this problem is to define all nested linked models as “Overlays” rather than attachments. When nested models are defined as overlays, Revit only locates one instance of each linked model in the host file, which is typically desirable behavior.