This page provides a step-by-step introduction to Exterior Lighting in V-Ray for Revit.


Page Contents

 

Introduction


In this tutorial we’ll go over lighting techniques for exteriors, following up on the previous tutorial on lighting interiors. Take a look through at least that previous video on lighting if you haven’t already, to get you primed on general lighting workflow.

To follow this tutorial, you will need to have the V-Ray for Revit plugin installed. This tutorial page is a companion that goes with the QuickStart video posted on our YouTube channel and is available here:

 

 

 

 

Tutorial Assets


To download the files used in this tutorial, please click on the button below. This Revit scene is provided by Karam Baki.


Tutorial Steps


Open the Example Scene

Go ahead and launch your version of Revit, here we are using 2017. Open the “exterior_lighting.rvt” project which you can download above. This project was created with Revit 2016, and will upgrade automatically if you open it with Revit 2017. Please note that Revit 2015 and earlier versions of Revit may have difficulty loading this project.

 

 

 

Lets get the scene ready for a quick V-Ray RT render to see how this looks.

Open the V-Ray Tab and click on Current View and select the Render view. Leave Quality on Draft. Click on Resolution in the V-Ray tab and select Crop Region. Select Printer with a DPI of 150 and close the window.

 

 

 

Setting up the Dome Light

Change from the V-Ray Sun to the Dome Light

 

 

 

Go to the Render With V-Ray drop down and select Render V-Ray RT.

 

 

 

The render shows a plain Dome color that gives an evenly-lit overcast look. This is due to a flat color being defined as the Dome light that surrounds the model. To fix this, use an HDR image for more detail in the environment light.

To add one, enable the Use HDR Image in the V-Ray Dome Light Settings window for more dynamic lighting.

 

 

 

 

 

Experiment with the Rotation value in the Dome Light Settings dialog to see how the lighting updates. This turns the orientation of the HDR image to essentially change the direction of the lighting.

 

 

 


Setting up the V-Ray Sun System

Now let’s switch back over to the Sun Light mode.

 

 

 

 

Using Azimuth and Altitude to change the angle of the Sun

Lets change the angle of the sun. Select the Render view. In the Project Browser and under the Camera section, click Edit to change the Render Settings.

 

Click on the Sun Settings ... button to access the sun angle parameters.

 

 

Experiment with some of these settings to get different looks from the sun lighting. When you are finished experimenting, proceed to the next steps.

 

In the Lighting Solar Study, Change the Azimuth to 180 and click Apply. The RT render will update and show a new lighting scheme. 

If you receive a Revit error when attempting to modify these parameters, open and close the Dynamo plugin from the Manage tab.

 

 

 

 

 To get the Sun higher in the sky, Set the Altitude to 54 degrees and click Apply

 

 

 

 

Using date and location to change the angle of the Sun

Now click the Still Solar Study to change the sun controls to be based on purely location, time & date parameters, instead of angle and azimuth. Change the month to 6 for June and the time to 10:00 AM and click Apply.

 

 

 

Feel free to try different settings to get a feel for how this works, but come back to these settings for date and time to follow along the rest of the tutorial.

 

Adding Artificial Lighting

Let’s get to work on adding artificial lighting to the render.

Click Stop in the VFB window to stop the RT render.

 

 


Turn on Artificial Lights and turn off the Sun environment light.

 

 

One trick to use when evaluating and testing your artificial lighting is to override the materials in the project, Having a uniform material on everything in the project will give you the best chance to really see how your lighting is operating.
To do this, Open the Material Browser. Open the Global Materials tab. Enable Opaque Material Override and the Transparent Material Override.

This will override the materials with a simple grey material with basic settings.

 

 

Start a new RT render.

 

 

It's quite dark, so the Camera can be adjusted to allow in more light,

Click on the Camera icon and set your Exposure to 5.

 

 

 

Disabling Lights

There are a lot of artificial lights that are turned on, so turn off a couple of lights to add more interest to the render. There are several different ways to turn off lights, but this time use Revit’s built-in Light Groups in the following steps:

Stop the RT render. Double click on the Render view in the Project Browser.

 

 

 

Zoom into some of these lights and click on them to see that they’re already set up in Light Groups. For more on Light Groups in Revit, Autodesk has great help sections in their documentation to show you how to set them up, so check that out as needed. This scene has Light Groups all set up in the project. 

 

 

To control the light groups, click down on the Show Rendering Dialog icon at the bottom left side of the Revit window.

 

 

 

Set the Lighting Scheme to a setting that includes "artificial lighting." I’ll select Sun and Artificial light. This will enable the Artificial Lights button. Press it.

 

 

 

This open window that gives you access to all the Lighting Groups in the project, grouped into floors and sections. You can see the light groups and the lights in them by collapse all the lists.

We can easily enable or disable groups to turn off lights in the render by clicking the checkboxes to clear them.

Turn off a few random spots of lights, including some lights that you can’t see in this view anyway. This will also help improve render times. Here, we'll turn off the following:

 

0-N, 2-SE, 2-SC, 2-NE, 2-NC, 2-NE, 3-SW, 3-SC, 4-NE, 4-SE

 

 


Once you’re happy with this, click OK and close out of this window. Switch over to the exterior lighting 3D view and restart the RT render. The some of the lights are now off.

 

 

 

 

Combining Artificial Light with Environment Lighting

Let's introduce some environment lighting back into the scene.

Click on the No Light pulldown and select the V-Ray Sun. We want to give this image a night time sky,

 

 

 

The render is incredibly bright, which is from when the Exposure value on the Camera was set to 5 earlier in the tutorial. Instead of adjusting the camera exposure, set the Sun Intensity to .0001. That gives a nice gradient night sky in the background. Of course, you can use an HDR instead of the Sun and that will look more realistic, especially with a good nighttime HDR image.

 

 

 

 

Production Render

The test RT rendering is coming out well, Stop the RT so we can start the final rendering. Change Quality to Medium, but leave the resolution as-is.

 

 

 

Now to turn off the material overrides, go to the Material Browser, and check these two overrides off and close the window.

 

 


Select Render with V-Ray to kick it off. After the first few pre-passes, The progressive render will resolve the image cleaner and cleaner over time. You can stop the render at any time once you achieve the quality level you like. Looks Neat!