Create virtual surfaces

Calculate the daylight indicators directly on model surfaces is not always possible. For instance, indicators such as Daylight Factor and Daylight Autonomy are usually calculated for virtual workplanes in the occupied spaces. Sometimes the complexity of the model makes it difficult to calculate on the actual surface.

The virtual surface creation features respond to these situations.

• Create copy
• Create copy in instances
• Create a copy for the surfaces of a tag (layer)
• Define virtual layers

And also:

• Show / Hide virtual surfaces

The virtual surfaces created with these tools are only used to position the sensors, they have no influence on the geometry of the model and light distribution.

Some cases when these features can be used:

• Model contains multiple instances of a component or a group, and calculation is needed on some surface inside component/group. If the calculation is performed on the original surface then its result will be applied to all instances of the surface, resulting in incorrect results (SketchUp just duplicates several times this area). Copying to instances resolves this problem.
• Some part of the target surface is intersecting with other geometry and results near intersection are not looking nice. Creation of a copy and calculation on it can give better results, since copy surface is created in new independent group.
• Calculation is needed on some virtual surface which is parallel to original surface. For example on a workplane that is offset from floor surface. Created copy surface won't interfere with existing building geometry.
• The surface to be calculated is imaginary, for example a vertical plane in front of a facade ignoring the cutting of the openings.

Create copy

This tool is used to create a single copy of the clicked surface on predefined distance. Distance can be changed in SketchUp bottom right edit box, once surfaces are created. The default distance (70 cm for most extensions) can be set in the preferences.

• For each clicked surface, a single copy surface is created and put in special tag/layer '_dl_[extension]_surface', where [extension] is abbreviation of active extension name.
• All copy surfaces are put in separate group, outside of any other model groups/components. Even if original surface(s) are part of a group/component, created copies are independent.
• If "Create copy" is called for a surface inside an instance of a group/component, it creates only single copy of the surface offseted from the selected surface.

This feature can be called from menu: Extensions-> De Luminae-> [Extension name]-> Create copy

Example:

• Creation of virtual surfaces 70 cm above the floor
  
• Calculation result
  

Create copy in instances

When SketchUp model contains several instances of the same component/group, surfaces within them should be distinct somehow. Due to the nature of SketchUp instances, it is not possible to attach different attributes and materials to surfaces inside each instance. To enable correct DL-Light calculation and results import into SketchUp, it is necessary to run calculation on 'dummy' surfaces, that would represent the real ones, but be outside of instances.

Tool 'Create copy in instances', creates one copy per instance of the clicked surface in a separate group. For example if there are 10 instances of the office component in the model, this tool would create offseted 'copy' surfaces for each office instance, resulting in 10 new 'copied surfaces'.

To use this tool:

• Open an instance of the component on the model containing the surface to copy.
• It may be necessary to successively open several levels of components.
• When the chosen surface is selectable, click on it with tool "copy in instances".
• Virtual surfaces should appear on all instances of the component (copies are made only on visible instances).
• The offset distance of the copy can be entered in SketchUp bottom right edit box. If this value is changed right after the copies are created, the copies are moved to the new distance.

If this tool is called for a surface that is not part of a component/group, it creates a single copy, like "Create copy" tool described above.

For each selected surface single copy surface is created and put in special layer '_dl_[extension]_surface'.
All copy surfaces created when "Create copy in instances" is clicked are put in separate group, outside of any other model groups/components.

This feature can be called from menu: Extensions-> De Luminae-> [Extension name]-> Create copy in instances

Create a copy for the surfaces of a tag (layer)

This tool creates a copy for each surface of the selected tag, at a defined distance. The distance can be entered in the tool window. The distance proposed by default is the offset distance configured for the extension.

• For each surface corresponding to the tag (or layer), a copy surface is created and put in special tag/layer '_dl_[extension]_surface', where [extension] is abbreviation of active extension name.
• It is possible to accumulate copies for several tags by repeating the operation for each tag.
• The "Min face area" field is used to limit the operation to surfaces with minimum area.
• The button Delete virtual surfaces deletes all virtual surfaces for the current extension (removal of the tag '_dl_[extension]_surface').
• All copy surfaces are put in separate group, outside of any other model groups/components. Even if original surface(s) are part of a group/component, created copies are independent.

This feature can be called from menu: Extensions-> De Luminae-> [Extension name]-> Create Virtual Copy for Tag

Example:

• Creation of virtual surfaces 70 cm above the floor for tag "floor 2":
  
• Virtual surfaces generated:
  

Define virtual layers

This advanced feature allows you to freely create virtual surfaces regardless of existing surfaces. It is useful:

• for rapid assessment of modifications of the existing (test location of solar panels for example),
• to make global measurements on the envelope of a structure,
• for any use not covered by the virtual surface system generated via a "copy" of a pre-existing surface.

Operation

• Create one or more surfaces in SketchUp.
• Bring these surfaces together in a dedicated layer.
• Convert this layer to "layer of virtual surfaces".
  • The function is available in the menu of the current extension: De Luminae-> [Extension name]-> Define virtual layers, or the button of the toolbar.
  • It displays a dialog that lists the visible layers, tick the layer to make it virtual.
    
    Remarks:
    • The layer '_dl_[extension]_surface' containing the surfaces created by the surface copy tool is listed, but its status is not alterable.
    • A message requesting confirmation is displayed for any modification. This confirmation request can be disabled in preferences.
    • When a layer takes the status "layer of virtual surfaces":
      • Any results or textures of the surfaces of this layer are erased.
      • Surfaces take on a yellow semitransparent appearance.
    • When a layer loses the status "layer of virtual surfaces":
      • Any results or textures of the surfaces of this layer are erased.
      • The surfaces become opaque again.

Example

• Purpose: evaluation of the light arriving on a facade
  
• Creation of a virtual surface, vertical and parallel to the facade
  
• Calculation result on the surface
  
• It is possible to use both virtual layers and virtual copies of surfaces (above floors)
  
• Interior virtual surfaces are well calculated behind the vertical virtual surface: the virtual surfaces are "Transparent".
  

Calculation with 'copy' surfaces

During calculation created surfaces are used for sensor points generation, and are otherwise "transparent" for calculation (they don't have any geometry, don't cause shadows, or reflect light).

Once results are calculated, they are imported onto copy surfaces, and not on original surface.

When a model surface that has been virtual-copied is modified, it is important to maintain consistency between the results and the geometry of the model. Follow this procedure to recreate the virtual surface:

• Select the virtual surface and remove it,
• Modify original surface geometry,
• Create a new virtual copy of modified surface,
• Perform the calculation on the new copy.

Show / Hide virtual surfaces

The virtual surfaces visibility button makes virtual surfaces invisible if needed. The initial configuration is to show the virtual surfaces, the button is activated.