Improve false colors

If falsecolor images aren’t mapped good, there could be several reasons and most of them can be solved easily:

Case 1

Material is not mapped good near surface edges or holes edges (color is changed towards green/blue) – start Show sensors and values tool  to see how they are positioned and if there are sensors near edges. If needed recalculate sun exposure for that surface with lower distance between sensors.
This kind of problem shouldn’t appear very often.

Case 2

If material is pasted completely wrong and sensors seem to be positioned well over plane surface, check if the face have collinear corner points (like some edge is composed of more than one line). This can cause wrong interpretation of plane corner points when false color material is pasted.
2 possible solutions – automatic and manual one:

  • Automatic model cleaning – If number of problematic surfaces is rather big, Sketchup model should be cleaned before SunExposure extension is used. To clean model use one of next tools:
  • Manual model cleaning – For problematic surface(s), find edges that are composed of more than one part. Delete edge lines and draw a single line instead (put line Layer to be the same as face layer).

After you clean the model recalculate SunExposure and import results again.
Note that for some surfaces this automatic cleaning may not solve the problem so manual cleaning is required.

Case 3

False color material pasting is obviously wrong, and surface(s) have very irregular shape or aspect ratio is too big/small.
Solution is to try to replace problematic surface(s) with one or multiple simpler surfaces, with more balanced aspect ratio and also put lower sensor distance for the surface.
Then repeat calculation and results analysis and import.

Case 4

If none of previous cases solve the problem, please inform extension authors on

Strange images

In order to color the whole surfaces from a set of discrete points, SunExposure uses several  interpolation techniques.  Depending on the shape of the faces, interpolation algorithms perform may leads to better or poorer results.

SunExposure automatically selects the interpolation algotithm that should give the best results.

In certain cases Automatic image interpolation algorithm selection, doesn’t give satisfying false color results on surfaces with constant values in sensors (over complete surface area or some part of surface area). If results aren’t as expected, try some of tips listed below:

  • Increase Level of details for sensors generation in  “SunExposure dialog”, and Run calculation for problematic surface’s with “Run selected“.
  • Change scale type to “Automatic linear scale” and “Rerun images“.
  • Change color limits in SunExposure dialog, to be further from exact sensors values for the problematic surface and then “Rerun images.”
  • Decrease number of colors in the palette – to avoid very narrow range of values for a single color.
  • Change image interpolation algorithm in ‘Preferences dialog’. Read Interpolation algorithms

Have in mind, that no interpolation algorithm is perfect :)

Sensors are not visible

If after calculation sensor points aren’t visible when toggled on, check menu option View->Guides. SketchUp treats construction points objects the same way as guides and if this option is not checked, sensors points won’t be visible.

Manage calculation time

In SunExposure calcultion time directly depends on the size of the model, on the number of surfaces to calculate and the density of sensors defined.

To use SunExposure more efficiently, we suggest:

  • to hide useless layers whose objects would not change SunExposure results (interior walls for instance)
  • to avoid selecting unimportant surfaces. Select all would work but would lead to the calculation of a large number of uninteresting surfaces
  • to use first a “simple” level of details to avoid launching longer calculation before the complete validation of the model
  • to avoid launching “Very detailled” calculation on all surfaces
  • to adapt the level of details to the size of the surface to calculate. A “Very detailled” level may be well adapted to Windows for example whereas it has little interest for a large outside area or a whole street

Message “Dispatcher not launched”

During a first calculation, an error message may appear to inform that the calculation was not started.

This message appears generally on Windows during a first calculation for a project or when the output directory has been changed.

When Windows works in a directory for a first time, it operates a series a verification that may take a long time. The surveillance mechanism inside SunExposure may then consider than some process is not working properly. We chose in that case the stop the calculation (even though waiting longer for Windows to finish would work).

It is sufficient to relaunch the calculation to solve the problem in most cases.

You’ll find in the Help pages other methods to solve the problem if it remains.


Some surfaces seem not calculated

A face in Sketchup has an orientation. Normal to the face may be oriented towards the outside (towards the sun in our case) or towards the inside (of the building in particular).

During SunExposure calculation, if the normal is oriented towards the interior, the calculated face is inside the building and never “sees” the sun. The face visible from the outside then appears not calculated.

To calculated that face correctly, you need to “invert the face” so that it “sees” the sun and relaunch the calculation for that face.


How to block False Colour palette ?

When I am satisfied by a false colour palette calculated by SunExposure, how can I block it so it is not recalculated during next calculation?

SunExposure systematically recalculates the false colour palette so that it is best adapted to the calculated surfaces in the model.

When you are satisfied with a palette, just go to the False Colour tab, change “Automatic Palette” into “Manual Palette“. The current palette will then be blocked and will be used during further calculations without modifications.

Sketchup 2014 [Windows] : If I double-click on a model on the network, SunExposure does not load correctly

In Sketchup 2014, the double-click on a skp model on a network (not on local disks) leads to an error in environmental variables for Sketchup.

Because of that, extensions cannot initialize properly. For example, with SunExposure, Sketchup console will display a long error message indicating that many SunExposure files could not be loaded.

As this bug is independent of Sketchup we cannot correct it.

However there is a version a Sketchup 2014 called MA (Maintenance 1) that corrects the problem.

For more information, have a look at the technical site for Sketchup versions and look for the paragraph “What’s new in SketchUp 2014 M1