Shop Solver

For instructions on how to use the Define Commands, please click here.

Define Plane

A plane is a flat 2-dimensional surface that extends infinitely far in all directions parallel with the plane.  A plane may be defined by any of the following:

By Coefficients

Through 3 Non-collinear Points
Through a Point and Parallel to a Plane
Parallel to a Plane at a Distance
Through a Point and Perpendicular to a Vector
Through 2 Points and Perpendicular to a Plane
Through a Point and Perpendicular to 2 Intersecting Planes
Through a Point and Tangent to a Cylinder


By Coefficients

PLANE/a,b,c,d
The parameters are the coefficients of the plane equation ax + by + cz = d  where a, b and c define the head of a vector that is normal to the plane and whose foot is at the origin.  "d" is the perpendicular distance from the origin to the plane multiplied by the length of the vector.  When the vector is a unit vector (i.e. a vector of length 1.0) the value of d is simply the perpendicular distance from the origin to the plane.  Otherwise d must be scaled to attain the desired distance from the origin.

In figure Plane.1 below, PL1 is a plane parallel to the XY plane at Z=4.0.  Setting a, b and c to define the unit vector 0,0,1 requires that d be 4.0 in order to scale the vector to a length of 4.0.

PL2 is a plane tilted on a 45 degree angle to the ZX plane and has a perpendicular distance of 5.0 from the origin.  Setting a, b and c to 0,3,3 (which is NOT a unit vector) requires that d be the desired perpendicular distance of 5.0 scaled by the length of the vector (4.24264).  The math follows:

Length of the vector normal to PL2 = SQRT(0² + 3² + 3²) = 4.24264
The desired perpendicular distance from the origin to PL2 is 5.0 so d = 5 * 4.24264 = 21.2132.

PL1=PLANE/0,0,1.0,4.0
PL2=PLANE/0,3.0,3.0,21.2132


Through 3 Non-collinear Points

PLANE/point1,point2,point3
The plane is defined as passing through 3 non-collinear (not all on the same line) points.


PL1=PLANE/P1,P2,P3


Through a Point and Parallel to a Plane

PLANE/point,PARLEL,plane
The plane is defined as passing through point and parallel to plane.


PL2=PLANE/P1,PARLEL,PL1


Parallel to a Plane at a Distance

PLANE/PARLEL,plane,modifier,distance
modifier: XLARGE | XSMALL | YLARGE | YSMALL | ZLARGE | ZSMALL
The plane is defined as parallel to plane.  The 2 planes are offset from each other by the given perpendicular distance.


PL2=PLANE/PARLEL,PL1,ZLARGE,5.0

The directional modifiers are defined here.


Through a Point and Perpendicular to a Vector

PLANE/point,PERPTO,vector
The plane is defined as passing through point and is positioned such that it is perpendicular to the given vector.


PL1=PLANE/P1,PERPTO,V1


Through 2 Points and Perpendicular to a Plane

PLANE/point1,point2,PERPTO,plane
The plane is defined as passing through point1 and point2 and is perpendicular to the given plane.  A line passing through the 2 points must not be perpendicular to the given plane.

PL1=PLANE/P1,P2,PERPTO,PL2


Through a Point and Perpendicular to 2 Intersecting Planes

PLANE/point,PERPTO,plane1,plane2
The plane is defined as passing through point and is perpendicular to both plane1 and plane2.


PL1=PLANE/P1,PERPTO,PL2,PL3


Through a Point and Tangent to a Cylinder

PLANE/point,modifier,TANTO,cylinder
modifier: XLARGE | XSMALL | YLARGE | YSMALL | ZLARGE | ZSMALL
The plane is defined as passing through point and tangent to cylinder.  The modifier defines which of 2 possible planes is desired by comparing their points of tangency with cylinder.



PL1=PLANE/P1,ZLARGE,TANTO,CYL1
PL2=PLANE/P1,ZSMALL,TANTO,CYL1

The directional modifiers are defined here.