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


Page Contents

 

Introduction


In this tutorial we’ll go over lighting techniques for an architectural exterior scene using both V-Ray’s Sun and Sky System, as well as Image Based Lighting with a High Dynamic Range Image with a Dome light.

To follow this tutorial, you will need to have the V-Ray for Rhino 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 Rhino scene is provided by Matúš Nedecký.


 

Depending on your browser, right-click the download button and choose "Save Link As..." or "Save target as..." to bring up a dialog to save the zip file without having to wait for the Preview mode to load.

 


Tutorial Steps


Open the Example Scene

Begin by launching Rhino. Open the project file QS_03_Start.3dm, which can be downloaded from the Tutorial Assets section above.

 

 

 

The scene is set up to use the default Rhino lighting using an HDRI for the illumination.

Since it's best to first judge the lighting independent of materials, first override all the materials in the scene. Open the Asset Editor as shown below.

 

 

 

In the Settings tab, turn on Material Override to temporarily assign a simple gray material on everything, which gives faster render feedback on the illumination itself.

 

 

 

Now launch an Interactive render. Click and hold the Render icon and choose Render with V-Ray Interactive.

 

 

 

The VFB opens, as the house render resolves with that default Rhino lighting. 

 

 

 

V-Ray Sun and Sky System

Now, to add V-Ray’s Sun and Sky:  In the Rhino UI, click on the Options gear icon shown below.

 

 

 

Now select Sun from the list shown below. 

 

 

 

This allows access to the Sun Options, seen here:

 

 

 

Then, turn On the Sun which adds more Sun options, as shown below. 

 

 

 

The VFB updates, lighting up our little house.

 

 

 

Setting up the Sky

Next, let's add the sky to the equation, and take out the existing HDRI.  In the Asset Editor, expand the Environment section and right-click on the Map icon for Background, and choose Clear to get rid of that existing HDRI environment as shown below.

 

 

 

Now click on the Map icon.

 

 

 

Now select the Sky texture from the list and then, click Back.

 

 

 

And now, as the image resolves you can see that it is over-bright.

 

 

 

This render is over-bright because the scene camera is exposed for the HDR lighting from before. Click to expand the Camera section and set the Exposure Value (or EV), to a higher value to allow less light into the camera. Set the EV to 12.5, that’s a good exposure now.

 

 

 

 

 

Now, experiment with the time of day and time of year a bit to see how the sun makes the house look. A wide range of looks is possible by just changing how the sun lights the house. Adjust the Year and Time sliders to see the how they affect the Interactive Render.  Then set your Year to 5/15/2017 and the Time to 8:44 AM, as shown below.

 

 

 

 

 

Setting up the Sun

Now, on to the sun’s settings.  In the Asset Editor, click the Lighting tab and here is the sun already in the scene by default in Rhino.  Click the arrow to expand the settings for the light.  

 

 

 

Let’s experiment with the Size Multiplier.  In the VFB, click on the Render Region icon and define the area of the image shown below.

 

 

 

Render Region keeps any updates to the render to only this part of the image for faster response. Zoom into the image as shown below, to focus on the sharp shadows. 

 

 

 

Set the Size Multiplier to 10, and the shadows soften quite a bit. 

 

 

 

 

 

Disable Region Render and evaluate how the soft shadows work for the whole scene.

 

 

 

Set the Size Multiplier back to the default of 1, and move on to changing the color of the sun itself. Click on the Filter Color swatch shown below, and try out some different colors. 

 


Once you're done experimenting with color options, set it to a very slight pale blue.  Set the values to those in the image shown below to match our choice of color.

 

 

 

And there we are, the illumination in the scene is pretty good.

 

 

 

Stop the Interactive render with the Stop icon in the V-Ray Frame Buffer.

 

 

 

Setting up the finishing touches

In the Asset Editor, in the Settings tab, disable the Material Override.  

 

 

 

Change to the Geometry tab and notice there is a pre-existing Grass in the scene made with V-Ray Fur.

 

 

 

Click on Grass and expand the Distribution section. Set the Per area value to 0.005, which populates the ground area with grass, and then close the settings. 

 

 

 

Click on the Layers tab and turn on BG_Plate, and it shows up in the scene. This is just a plane geometry with a texture applied to it for a simple background to fill out the scene.

 

 

 

In the Asset Editor, select the Settings tab, and in the Render Output section, set the resolution to 1280 x 720 and set the Quality to High.  Then turn off both Interactive and Progressive, and start a production render.

 

 


 In the V-Ray toolbar, shown below, click the Render with V-Ray icon.

 

 

 

 

 

Once the render is finished, click on the Show Corrections Control icon shown below, and make image adjustments using the control panel on the right in the VFB.

 

 

 

Start with more contrast using the Curve control. Set a curve like the one seen here:

 

 

 

Then move on to Hue/Saturation to boost the color a little bit to add some vibrancy.  Set Hue to -6.11 and Saturation to 0.44.

 

 

 

Then to Color Balance to adjust the midtones to give some added warmth.  Check the Midtones box, set Cyan to 0.15, Magenta to -0.07, and Yellow to 0.03.

 

 

 

Now click on the Open lens effects settings icon shown below, to open its panel on the left of the VFB.

 

 

 

Turn on the Bloom Effect and give it a Weight of 15, a Size of 77, and a Shape of 4, to give the image a more photographic feel.

 

 

 

And there you have it! You can save this image at this point before moving on to using another lighting workflow, next.

 

 

 

Using a V-Ray Dome light to light the exterior scene.

In the VFB, turn off the Bloom Effect and all the Color Corrections, and then close the window. 

 

 

 

In Layers, turn off the BG_Plate, by clicking on the light-bulb icon seen below.

 

 

 

In the Geometry tab, select the Grass and in the settings Distribution section, set Per area to 0, to get rid of the grass.

 

 

 

Turn to the Settings tab, and turn on Material Override to be able to judge just the illumination of the scene.

 

 

 

In the Render Output section, set the resolution down to 960 x 540 for faster render times.

 

 

 

Start an Interactive Render, and the results show that the Sun and Sky system is still in the scene, as seen below.

 

 

 

 

 

In the Asset Editor under the Environment section, disable the Background to disable the Sky, which turns the sky black.

 

 

 

 

 

Then in the Lights section, disable the Rhino Document Sun.

 

 

 

Click over to the V-Ray Lights tab in the V-Ray Toolbar, and click on the Dome light icon shown here:

 

 

 

Click in your scene to place the Dome Light, and a file dialog pops up. Select the HDR image file shown below, which is found in the downloaded assets for this tutorial.

 

 

 

The image is a little dark; it is not as bright as the sky texture from earlier in the tutorial. One option is to increase the Intensity of the Dome light in the Asset Editor.

 

 

 

With the Dome Light selected, click the arrow to expand the settings for the light and adjust the Intensity to 2.

 

 

 

 

 

But when you’re using an HDR image, especially a properly assembled and calibrated HDRI like many that you can download, it is not the preferred workflow to simply boost the Dome light intensity as in the previous step, so set it back down to 1.

Then, go to the Settings tab, and in the Camera section, set the EV to a lower value to let in more light.  Set the EV to 11.5 as it works quite well for the image. 

 

 

 

In the scene, select the Dome light and rotate it to re-orient the HDR image, using the Interactive Render to gauge how you set its orientation for the best look.

 

 

 

When satisfied, stop the Interactive Render using the Stop Button in the V-Ray Frame Buffer shown below. Let’s get to a production render.

 

 

 

 

Click on the Layers tab and turn on BG_Plate, to have it in the scene again.

 

 

 

In the Asset Editor, under the Geometry tab, select the Grass, and under Distribution reset the Per area back to 0.005.

 

 

 

In the Settings, turn off Material Override.


 

 

In the Asset Editor, select the Settings tab, and in the Render Output section, set the resolution to 1280 x 720 and set the Quality to High.  Then turn off the Interactive and Progressive toggles, and start a production render.

 

 

 

 

 

When the render finishes, click Show corrections control (shown below), and enable Hue/Saturation, Color Balance, and Curve to apply the previous color corrections, and then adjust the color more, to suit your own taste.

 

 

 

 

 

Now click on the Open lens effects settings icon to open its panel on the left of the VFB.

 

 

 

Turn on the Bloom Effect again, and you are finished with your render!