Define here the projection parameters applied by default when creating a new layer.
Perspective, Orthographic
Set the projection that is applied by default when creating a new layer.
GAMGI projects the 3D layer space on the 2D screen using
Perspective
or
Orthographic projections. The
Perspective projection
is better to simulate realistic views, but the
Orthographic
projection preserves object dimensions, as these are not distorted
by perspective.
Near, Far, Top
Set the dimensions of the space volume that by default
is visible to the observer, after being projected into the
window graphic area.
This projection volume has six faces, and the front and back faces
are always perpendicular to the viewing direction.
Near and
Far set the default distances from the observer to these front
and back faces, corresponding to the minimum and maximum distances
that the observer can see.
Near must be smaller than
Far.
In a
Orthographic projection, the projection volume is a rectangular
parallelepiped, so the 4 lateral faces are paralell and perpendicular to
each other. In a
Perspective projection, the projection volume is
a truncated quandrangular pyramid, with the apex at the view point.
Top defines the half-height of the front face of the projection
volume. The width is automatically determined from the ratio height / width
of the window graphic area, so everytime users resize this window, the
projection volume changes accordingly. Increasing
Top increases
the visible volume and decreases the size of the objects.
Each layer has its own projection parameters, so in a window with
multiple visible layers, the image rendered in the graphic area
is the superposition of the various, totally independent, layer
views.