Relevant to Blender v2.31

Adds a background image (environment map), colour or sky to your render.

Pathlight and Hemilight can sample the background colour and intensity to simulate real world lighting.

Normal Image Background

<background type="image" name="envnorm" power="1.000000">
  <filename value="C:\directory\image.jpg"/>

HDRI Background

<background type = "HDRI" name = "envhdri" exposure_adjust = "0">
  <filename value = "C:\directory\image.hdr" />

Constant Background

<background type="constant" name = "constbackg">
  <color r="1.000000" g="1.000000" b="1.000000"/>

Sun/Sky Background

<background type="sunsky" name ="Sun1" turbidity ="4.000000" add_sun="on" sun_power="1.000000"
  a_var="1.000000" b_var="1.000000" c_var="1.000000" d_var="1.000000" e_var="1.000000" >
  <from x="-0.007401" y="8.589217" z="3.737965"/>