8

Home Grid: Views Based on the World Coordinate Axes 23
Home Grid: Views B ased on the
World Coordinate A xes
The grid you see in each viewport represents
one of three planes that intersect at r ight angles
to one another at a common point called the
origin. Intersection o ccurs along three lines (the
world coordinate axes: X, Y, and Z) familiar from
geometry as the basis of the Car tesian coordinate
system.
Home Grid
Using the home grid to position houses
The three planes based on the world coordinate
axes are ca lled the home g rid; this is the basic
reference system of the 3D world.
To simplify the positioning of objects, only one
plane of the home grid is visible in each viewport.
Thefigureshowsallthreeplanesastheywould
appear if you could see them in a single perspective
viewport.
Axes, Planes, and V iews
Home grid axes and planes
Twoaxesdefineeachplaneofthehomegrid.In
thedefaultPerspectiveviewport,youarelooking
across the XY plane (ground plane), with the X
axis running lef t-to-right, and the Y axis r unning
front-to-back. The third axis, Z, runs vertically
through this plane at the origin.