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Horizon 953
Horizon
Horizoninthedistanceofascene
Thehorizonofasceneistheedgeofvisionat
the heig ht of the camera, paral lel with the world
coordinate plane. You c an view the horizon in
camera viewports.
A camera is level when it and its target are the
same height from the world coordinate plane. In
other words, the camera’s local Z axis is parallel
to the world plane. When the camera is level, the
horizonlineiscenteredintheviewport. Asthe
camera ti lts up, the horizon line lowers; as it ti lts
down, the horizon line raises.
The horizon line can help you match the
perspective of your scene to the p erspective of
a still image. In general, matching perspective
involves the following steps:
• Display the horizon line. Use it to help you
adjust the cam era and target so they are level.
• Display the image in the camera viewport. Use
Views menu > Background Image.
• Orbitthecamerauntiltheperspectiveofthe
scene roughly matches that of the still im age.
• Adjust the camera’s perspective to fine-tune the
perspective match.
• Mov e the camera or target to position the scene
against the background.
If you raise or lower the camera, raise or lower the
target by an equal amount, in order to keep them
level and maintain the horizon.
Hot
A hot mater ial is one that is instanced in both the
sceneandtheMaterialEditor.Whenyougeta
material from an object, that material is hot. Any
changes you make to the hot material are reflected
in the scene wherever that material is applied.
To edit a material without changing the scene, you
can get the hot material from an object, then make
acopyofit. Thetermforthecopiedmaterialis
cool (page 3–924).
White tr iangu lar tabs in each corner of the
Material Editor sample slots (page 2–1420) show
that the materials in those slots are hot.
In the Material Editor, the only time you need to
select an object is when you’re assigning a material
to an object. When you’re adjusting a material,
object selection doesn’t matter.