Home Tips & Tricks Usage of Soft shadows in SketchUp and how it helps to create realistic lighting

Usage of Soft shadows in SketchUp and how it helps to create realistic lighting

by global

Soft shadow and its scope

Soft Shadow is a special tool in space design to create an image in SketchUp with Softer shadows from the Sun. It falls under the Lighting Technology which automatically lightens up the default settings.

To start select softness and coarseness below:

Use Medium for your first trial – it will merge about 25 images. Remember sketchy Shadows don’t work in ground plane. For softness and width of shadow images the shadow tab provides a set of pre-sets:

Shadow Softness – None, Coarse, Medium, Smooth or Custom – sets number of iterations. 

Shadow Spread – Narrow, Medium, Wide or custom – sets days and time to process.

There are various quick shadow modes like: 

  • Soft shadow 
  • Sketchy shadow

Soft shadow tab

The Soft shadow Tab consists of two properties. Shadow processing and Shadow masking.

Shadow Processing 

Shadow processing helps to surface the shadows in shade. The areas not in direct sun will be treated as shadowed areas.

Shadow Masking 

Shadow masking button will help to recreate the soft shadow image. This will only soften shadows where shadows appear in original image.

There are other buttons as well in the Soft shadow Tab, and each of the tabs have different functionalities, like shadow mode, Darkness opacity which helps to change the darkness of the shadows. The shadow pattern will be partially transparent, allowing the colours below it to bleed through.

SketchUp Water Mark Style

Soft Shadows also works with watermark SketchUp styles. This image was made using the NrpTools Crayon style. The watermark mostly, only appears in the dark, (shadowed) areas of the model.

Using Full Shadows

This button recreates all areas which are not in direct sunlight.


One can specify a Chipboard texture, or can select an image to use as a texture. The texture image will be applied to the shadows directly, and not applied to the surfaces in the model. This means that the texture will not rotate to match surfaces, and will not get smaller in the distance.

The main buttons to craft a Lighting Technology in SketchUp is the application of Soft Sun Shadow.

Soft Sun shadow

The process to make soft shadows from the sun using SketchUp‘s Shadow rendering is very easy. Using SketchUp’s shadow renderings creates several images at different times or dates, so we get different types of shadows and then combining them in to an image with softer shadows.

Soft Artificial Shadow 

One can also use to make soft shadows with a Ray Trace Rendering add on for SketchUp. This button also helps in moving the lights and merge images where are some renderers allows to specify larger surfaces for the lights and automatically sample multiple positions from each surface to create the shadows.

How to apply soft shadow from the Sun

If the drawing is getting sharp shadows under the Sun, in Vray for SketchUp, one can edit the sun settings. The process is explained in a detailed form:

1) Environment > GI (skylight) and click on M 

2) Under “Sun” change the “Size” from 1,0 to 25-30. 

3) This increase will cause the softer shadows, and make the sun larger in the render; one can also disable the sun above in case the appearance of the sun is not needed, or disturbing.

Lighting plays an important component of a successful render, especially when one is revealing indoor spaces. Realistic lighting is crucial to creating not only realistic scenes but also to leaving a lasting impression and conveying a certain feeling. Soft shadow can add a great detail of realism to any rendered scene by simply blurring or fading the edges of the objects. Hence, we can term Soft shadow as an important tool for SketchUp.

Related Articles