Position Class

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The position class holds a single 3 component position. A position is a single point in space, and it's important to use a position or vector as appropriate for the data that is being calculated, since matrix operations on them will end in different results. When being multiplied by a Matrix, this class will implicitly have a 4th component (W component) of 1. If the Matrix is a projection matrix that will cause the W component to become something other than 1, all 4 components will be divided by W to make the position homogeneous again. A new position can be created without any arguments, with 3 arguments for the x,y,z values, or with a single argument which is a variable that has 3 entries such as a list of length 3, or another position or vector.


Examples of creating a position:

p = tdu.Position() # starts as (0, 0, 0)
p2 = tdu.Position(1, 5, 0)
values = [0, 1, 0]
p3 = tdu.Position(values)


Members[edit]

xfloat :

Gets or sets the X component of the position.

yfloat :

Gets or sets the Y component of the position.

zfloat :

Gets or sets the Z component of the position.

Methods[edit]

translate(x, y, z)None:

Translates the position by the specified values.

  • x, y, z - The values to translate by.
p.translate(5, 2, 0)

scale(x, y, z)None:

Scales each component of the position by the specified values.

  • x, y, z - The values to scale each component of the position by.
p.scale(1, 2, 1)

copy()tdu.Position:

Returns a new position that is a copy of the position.

newV = v.copy()

Special Functions[edit]

tdu.Position[i]float:

Gets or sets the component of the position specified by i, where i can be 0, 1, or 2.

y = p[1]
p[1] = y + 2.0

tdu.Position * floattdu.Position:

Scales the position by the give float scalar and returns a new Position as the result.

p = p * 0.1
p = 0.1 * p

tdu.Position + floattdu.Position:

Adds the given scalar to all 3 components of the position and returns a new position as the result.

p = p + 1.2
p = 1.2 + p

tdu.Position - floattdu.Position:

Subtracts the given scalar from all 3 components of the position and returns a new position as the result.

p = p - 1.2
p = 1.2 - p

tdu.Vector + tdu.Positiontdu.Position:

Adds the vector to the position. ie. it displaces the given position by the vector. Returns a new position as the result.

p2 = v + p1
p2 = p1 + v

tdu.Position - tdu.Vectortdu.Position:

Subtracts the vector from the position. Notice that the reverse is not a legal operation: subtracting a position from a vector does not have any meaning. Returns a new position with the results.

p2 = p1 - v

tdu.Position - tdu.Positiontdu.Vector:

Subtracts the two positions to create a vector that is pointing from the 2nd one to the 1st one, with length equal to the distance between the positions.

v = p1 - p2

tdu.Position += floatNone:

Adds the given scalar to all 3 components of the position, the position will contain the result of the operation.

p += 0.1

tdu.Position += tdu.VectorNone:

Displaces the position by the given vector, the position will contain the result of the operation.

p += v

tdu.Position -= floatNone:

Subtracts the given scalar from all 3 components of the position, the position will contain the result of the operation.

p -= 0.4

tdu.Position -= tdu.VectorNone:

Displaces the position by the given vector, the position will contain the result of the operation.

p -= v

tdu.Matrix * tdu.Positiontdu.Position:

Multiplies the Position by the matrix and returns the a new position as the result.

p2 = m * p1

tdu.Position / floattdu.Position:

Divides each component of the position by the scalar and returns the a new position as the result.

p2 = p1 / 2.0

tdu.Position *= tdu.MatrixNone:

Multiplies the position by the matrix, the position will contain the result. The is position multiplied on the right of the matrix. It is the equivalent of doing Position = Matrix * Position.

p *= m

tdu.Position *= floatNone:

Scales all 3 components of the position by the given scalar. The position will contain the result.

p *= 1.3

tdu.Position *= tdu.PositionNone:

Component-wise multiplies the 3 components of the first position by the 3 components of the 2nd position.

p1 *= p2

abs(tdu.Position)tdu.Position:

Returns a new position with all 3 components being the absolute value of the given position's components.

p2 = abs(p1)

-tdu.Positiontdu.Position:

Returns a new position with all 3 component's being negated.

p2 = -p1


An Operator Family that contains its own Network inside. There are twelve 3D Object Component and eight 2D Panel Component types. See also Network Path.