IRender Background Tab

Background Tab

Background 72.png

The Background Tab is used to define background image and also for Ground Plane materials.

Background Image

  • Click Browse to select an image to use for the background.
  • Click Clear to clear the background image.


  • Visible - image is visible (will override any sky settings)
  • Reflected - image is reflected in windows.


This determines how the image is projected onto the sky of background.
  • Flat
  • Cylindrical
  • Spherical

Create Planar HDRi Image

Converts a normal image to a HDRi background image.
See: Planar HDRi Backgrounds


Clear out Background Image


Select HDRi Image from disk


Offsets and Scales

Use the Image Layer Wizard to size and position the background image and set these values.


for Cylindrical and Spherical Projections.

Maintain Aspect Ratio

if this is not checked, the background image is stretched to fill the screen.

Adjust Center Line to Horizon

If checked then the image will be scaled and offset so that the horizontal center line of the image matches the horizon of the current perspective view.
The image is scaled and positioned so that it still fills the entire background of the rendered image.
See: Horizon


Resets Offsets, Scales and Rotation.


Loads the Background Wizard to easily position and scale the background image.
See: Background Image for examples.

Ground Plane

  • On - turns on the Ground Plane
  • Alpha Channel - makes the ground plane transparent, but shows the shadows on the ground.
    See: Alpha Channel
  • Elevation - set the elevation of the ground plane.
  • See: Ground Plane

Ground Plane Material

  • From the Background Tab you can define and edit materials for the Ground Plane.

This lets you apply a grass texture for land, or a Procedural Bump Map and reflection to emulate water.

  • See: Background Tab

Alpha Transparent Ground Plane

With an Alpha Transparent Ground Plane, you can save the rendering as an Alpha Transparent image, and the ground plane will be transparent. However, shadows on the ground will be visible. This can be used to place the ground plane image on top of a background image and still see where the shadows would appear. (Of course this works best if you are placing he image on a flat surface.)

Other Setup Options