Fixture placement is a feature that allows you to place a large number of fixtures at the same time. You can create a fixture placement either with an obj or a csv file and in this guide we’ll explain the process using obj file. In short, Lightact can analyze the objects included in the obj file and place selected fixtures at the same positions, and in some cases with the same rotations, as the objects in the file.
In this window, you’ll see 3 areas:
- In area 1, you select the obj file that should be used for the Fixture placement.
- In area 2, you select which fixture should be placed according to the selected obj and click on Include button afterwards. You can include several fixtures with different placement obj files.
- Once you’ve included at least one fixture, you’ll be able to apply various filters in area 3.
- Finally, in area 4, you can enter Placement scale.
Selecting the obj and the fixture and adjusting the filters
Select the obj you want to use as the source, then select the fixture you want to place and click on the Include button. You’ll see the selected fixture appear on the right side where you can adjust the filters.
At the top, you see the name of the fixture and the obj that is going to be used for the placement. You’ll also see 3 tabs – one for each type of a filter.
Type filter is enabled by default. If you select Coplanar then only objects with all vertices on the same plane will be considered for the placement (for more info on what coplanar means, check this Wikipedia page). So, for example, if in the obj file you’ve got a cube and a plane, then only the plane will be considered for placing the fixture. If, on the other hand, you select 3D, then only 3D objects (objects that are not coplanar) will be considered.
If you’ve selected Coplanar, then you can also select Automatic orientation.
If you’ve selected Automatic orientation then Lightact will attempt to match the orientation of the inserted light fixtures with the orientation of rectangular planes represented in the obj file. This works for:
- rectangular planes represented as a quad with 4 vertices,
v -2.00000000000000 0.00000000000000 -2.00000000000000 v 2.00000000000000 0.00000000000000 -2.00000000000000 v -2.00000000000000 0.00000000000000 2.00000000000000 v 2.00000000000000 0.00000000000000 2.00000000000000 # 4 vertices o Plane usemtl default f 1 3 4 2
- rectangular plane represented as 2 triangles (triangulated quad) with 4 vertices,
v -43.94887748400507 36.87398274755398 -27.76138896752529 v -43.94887748400507 35.87398470067897 -27.76138896752529 v -43.89887748400507 35.87398470067897 -27.76138896752529 v -43.89887748400507 36.87398274755398 -27.76138896752529 # 4 vertices o Polygon usemtl default f 1 4 3 f 1 2 3
- rectangular plane represented as 2 triangles (triangulated quad) with 6 vertices 2 pairs of which are identical (doubles). This means Lightact conveniently performs the ‘Remove doubles’ operation for you.
v -79.143417 21.104847 71.800194 v -79.143417 20.254868 71.816147 v -79.072319 20.254868 71.816147 v -79.143417 21.104847 71.800194 v -79.072319 21.104847 71.800194 v -79.072319 20.254868 71.816147 s 1 f 12 11 10 f 9 8 7
For example, this file includes 4 planes represented as a quad.
If you use it as the source of an obj fixture placement, you’ll get something similar to the above. The offset between the fixtures and the planes is due to the offset between the location of the placed obj file and the Fixture placement.
Lightact matches the longest dimension of the fixture in the Fixture editor window with the longest dimension of the plane. If you want to do the opposite, which means matching the shortest dimension of the fixture with the longest dimension of the plane, then you should check the Match short to long.
If you enable this filter then Lightact will consider only the objects that have more or equal vertices than Min value and less or equal vertices than Max value. This is useful if you are using an obj that has other objects in them such as a complex 3D model with lots of vertices.
Size filter calculates the surface area of coplanar objects. If you enable this filter Lightact will consider only planes with the surface area larger or equal than Min value and less or equal than Max value. Please note that it works only for planes with 4 vertices (either quads or triangulated quads).
Analyze & Add
Before clicking on Add it is good a practice to click on the Analyze button for each type of fixture you are adding.
This way you’ll see how many fixtures of this type you’ll add based on the filters you enabled.
When you click on add, Lightact will add a separate Fixture placement for every fixture type you’ve included.