Sensors selection

The "detail" menu allows to select the organization and the density of sensors.The list shows the sensors grids provided by default and the custom grids. The default grids are not editable, but it is possible to use them to define custom grids (see below).
All sensors grids automatically seek to position themselves parallel to a longer segment, maximize the number of sensors on the surface, and center on the edges.

DL-Light sketchup daylighting extension sensors grids detail select

Types of sensors grids:

Density sensors grids - these grids use an advanced algorithm that places the sensors on the surface in a density grid, along the edges and finally in the corners (segment ends). This type of grid is particularly suitable for surfaces with complex shapes, the mode "Sensors coverage area" is recommended (see below advanced settings preferences).
The algorithm has 4 parameters:
- Density: number of sensors per square meter. This density is indicative, the final density may be slightly higher.
- Distance to the edges: minimum distance between sensors and edges of surfaces.
- Corner sensors: try to put sensors in the corners of the surface.
- 3x3 sensors: try to have at least 3 sensors in each direction, possibly at the cost of increasing the density.

The provided grids:

Sparse - approximately 1 sensor every 10 square meters, distance to the edges: 10cm, corner sensors: yes, 3x3 sensors: no.
Simple - approximately 1 sensor every 4 square meters (sensors 2 meters apart in each direction), distance to the edges: 10cm, corner sensors: yes, 3x3 sensors: no.
Detailed - approximately 1 sensor per square meter, distance to the edges: 10cm, corner sensors: yes, 3x3 sensors: no.
Very detailed - approximately 4 sensors per square meter (a distance of about 50cm between sensors), distance to the edges: 10cm, corner sensors: yes, 3x3 sensors: no.
SF, HSA, NSL grids: these are very dense grids intended for certain calculations such as the calculation of horizontal sight angle.

EN 12464-1 standard - grid in accordance with EN 12464-1 standard requirements, with approximate distance between sensors p = 0,2 × 5^log10(d) meters, where d is the longest dimension of the calculation area if the length-to-width ratio is between 0.5 and 2.0. For other ratios shorter dimension is used for d.
Nota:
- this grid is used for BREEAM calculations mode,
- for a length d=10m, the size of the mesh is 1.00m.
EN 17037 standard - grid in accordance with EN 17037 standard requirements, with approximate distance between sensors p = 0,5 × 5^log10(d) meters, where d is the longest dimension of the calculation area if the length-to-width ratio is between 0.5 and 2.0. For other ratios shorter dimension is used for d. The surface of the mesh excludes a band of 0.50m along the walls, the grid is calculated on this reduced surface.
Nota:
- grid used by default for Daylight Factor and Horizontal Sight Angle in EN 17037 mode,
- for a length d=10m, the size of the mesh is 2.50m
- the density of the mesh proposed by EN 17037 standard is much lower than for EN 12464-1 (in ratio greater than 6).
Single sensor in the center - the surface receives only one sensor, located in the center (or close to the center for surfaces with holes).
Note: grid used by default for APSH calculation.
Classic sensors grids - regular rectangular grid (the spacing between sensors is fixed), this is the simplest grid.
These grids have 2 parameters:
- Spacing: distance between the sensors. The distance is the same in both directions.
- Distance to the edges: minimum distance between sensors and edges of surfaces.
Provided grid:
- 50cm grid - grid with a sensor every 50cm and a minimum distance to edges of 50cm.

Advanced preferences settings

The following parameters are adjustable in the advanced preferences of each extension and affect the interpretation of the sensors:

DL-Light sketchup daylighting extension sensors grids prefs en

Min face area - Minimal surface area, below which surface is skipped as extremely small. If this limit is zero, a surface can still be discarded if the distance limit at the edges of the sensor grid does not allow a sensor to be positioned.
Area limit for single sensor - Area below which a single sensor is generated for the surface.
Coverage area of sensors - Boolean - If enabled, assign to each sensor a coefficient corresponding to the area covered by the nearest points (Voronoi diagram). The traditional alternative is to consider that each sensor represents the same surface, which can lead to anomalies (sensors in the corners). In general this option is recommended to obtain coherent and precise results, but it is not recommended for the calculations having to respect a standard specifying that each sensor must have the same "weight" (for example BREEAM).

These 2 options have no influence on the sensors and the values returned in the reports, they only concern the rendering of the textures:

Interpolation density - Adjusting the ratio of interpolated points by sensor, improve the graphic rendering (for modes RBF and linear interpolation).
Maximum scale in pixels / meter - Limit the texture dimension to a maximum of pixels per meter. The largest dimension of a texture is defined in the preferences (for example 1024 pixels). This second parameter also makes it possible to enforce a limit based on the dimensions of the surfaces. This makes it possible to maintain a coherent graphic rendering for successive calculations on surfaces of very different sizes.

Custom sensors grids

Two dialogs allow you to define custom sensors grids for both types (density and conventional). These dialogs take the parameters described above. The default grids are presented in these dialogs for information purposes.

Features

Local storage - defined grids are saved in the local instance of SketchUp and can be used on any model (either as the main sensors grid or for exception surfaces).
Model storage - any grid used in a model is also stored in the SketchUp model.
Removing grids - Removing a grid (red cross icon) deletes the grid only locally, but never from the model that uses it. As a result, there is no point attempting to erase a grid used in the current model. To remove a grid from a model, it must be ensured that it is no longer used by any calculation on the model.
Automatic loading vs naming - When loading a model, the grids used by the model are automatically loaded. The name of the sensors grids is therefore indicative, 2 identical grids can exist under 2 different names, 2 grids with the same name but with different parameters can coexist. The management of naming rules is left to the local organization.

Density sensors grids

The dialog is accessible from the SketchUp menu:
Extensions -> De Luminae -> Global Parameters -> Custom Density Sensors Grids

It is also accessible from the Grid Exceptions dialog on surfaces.

DL-Light sketchup daylighting extension sensors grids custom density win en

Classic sensors grids

The dialog is accessible from the SketchUp menu:
Extensions -> De Luminae -> Global Parameters -> Custom Sensors Grids

It is also accessible from the Grid Exceptions dialog on surfaces.

DL-Light sketchup daylighting extension sensors grids classique win en

Exceptions - sensors grid specific to a surface

This dialog allows you to select a specific sensors grid for a model surface. It is accessible through the Exceptions button to the right of the main grid selector.

DL-Light sketchup daylighting extension sensors grids specific win en

Each line of the table corresponds to a surface of the model.

Windows only : click on "loupe" icon displays a mask on the model that locates the surface.
Mac OS only : selecting a row in the table displays a mask on the model that locates the surface.
Clicking on a face of the model loads the face into the table (or selects it). Initially, the table is empty if all the surfaces use the default grid, it is then necessary to click on the faces to be modified.
The Custom grids and Custom density grids buttons provide direct access to grid characteristics via the dialogs described above.

Definition of columns:

Face name - Name of the face (by default its numerical identifier). The name is editable.
Layer - Name of the layer to which the surface is attached.
Grid - The name of the currently assigned grid. If the default grid is used, the name of the grid is preceded by the word "Default:". Click on the cell to select a grid to use from the drop-down list (browse through the list using the mouse wheel or keyboard).
Add layer icon - Apply the grid of this surface to all surfaces listed in the table that are attached to the same layer.
Face comments - Comment associated with the face. The comment is editable.
Delete icon - Remove the face of the table, so the face uses the default grid.