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Manual - Blender 2.4x

[edit] World Background

[edit] Description

The world buttons let you set up the shading of your scene in general. It can provide ambient colour, and special effects such as mist, but a very common use of a World is to shade a background colour.

[edit] Options

Background colors

HoR, HoG, HoB

The RGB color at the horizon

ZeR, ZeG, ZeB

The RGB color at the zenith (overhead)

These colors are interpreted differently, according to the Buttons in the Preview Panel (Background colors):

Blend

The background color is blended from horizon to zenith. If only this button is pressed, the gradient runs from the bottom to the top of the rendered image regardless of the camera orientation.

Real

If this option is added, the gradient produced has two transitions, from nadir (same color as zenith) to horizon to zenith; the blending is also dependent on the camera orientation, witch makes it more realistic. The horizon color is exactly at the horizon (on the x-y plane), and the zenith color is used for points vertically above and below the camera.

Paper

If this option is added, the gradient keeps its characteristics, but it is clipped in the image (it stays on a horizontal plane (parallel to x-y plane): what ever the angle of the camera may be, the horizon is always at the middle of the image).

[edit] Textures

Instead of a color, or blend of two colors, Blender can use an 2D image which it maps to a very large Box or sphere which encompasses the entire scene, or which it maps to a virtual space around the scene.

Texture buttons

The World Buttons also provide a stack of texture channels. They are used much like the Materials textures, except for a couple of differences (Texture buttons). The textures can be mapped according to:

View

The default orientation, aligned with the co-ordinates of the final render

AngMap

Used to wrap a standard hemisphere angular map around the scene in a dome. This can be used for image based lighting with Ambient Occlusion set to sky color. You'll generally need a high dynamic range image (HDRI) angular map (the look like a weird spherical image).

Sphere

Sphere mapping, similar to that of materials

Tube

Wrap the rectangular texture around in a cylinder, similar to that of materials

Object

Position the texture relative to a specified object's local texture space

The texture affects color only, but in four different ways:

Blend

Makes the Horizon color appear where the texture is non-zero

Hori

Affect the color of the horizon

ZenUp

Affect the zenith color overhead

ZenDo

Affect the zenith color underneath

Manual