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Pose

Package name: jitx/pose

Location in the Kinematic Tree

The Pose type is used to move a component, pad, shape, or other instances within a definition's coordinate frame.

The following definitions have a default coordinate frame:

These definition types have a right-handed coordinate frame centered at (0.0, 0.0) and axis aligned with the X and Y axis.

When creating an instance in these coordinate frames we use the loc helper function to create Pose objects that transforms the instance's X,Y position and rotation.

loc syntax

Typical Syntax:

loc(x, y, [angle, flip-x])
loc(center, [angle, flip-x])
  • x, y or center is a Point defining the translation of the coordinate frame.
  • angle is the right-hand rotation of the coordinate frame in degrees. This parameter is optional and the default is 0.0.
  • flip-x is the mirroring of the coordinate frame across the Y axis. This parameter is optional and the default is false.

These operations are performed in the following order:

  1. Flip
  2. Rotate
  3. Translate

There are several other variants of the loc function defined below.

Translation Example

val p1 = Point(1.0, 5.0)
val tx = loc(1.0, 1.0)

val p2 = tx * p1
println(p2)
; Point(2.0, 6.0)

This transformation is a pure translation of the point p1 by the transform tx

Rotation Example

val p1 = Point(1.0, 5.0)
val tx = loc(1.0, 1.0, 90.0)

val p2 = tx * p1
println(p2)
; Point(-4.0, 2.0)

Notice that in this example - the rotation by 90 degrees is applied first, and then the point is translated by (+1.0, +1.0)

Transform Chaining

Transformations can be chained to form a transformation sequence: 

val p1 = Point(1.0, 5.0)
val tx1 = loc(1.0, 1.0, 90.0)
val tx2 = loc(0.0, 0.0, 180.0)

val p2 = tx2 * tx1 * p1
println(p2)
; Point(4.0, -2.0)

val p3 = tx1 * tx2 * p1
println(p3)
; Point(6.0, 0.0)

Here the final operation flips the coordinate frame about the Y axis.

The order of the applied transformations is important. These transformations are not commutative.

Localization Syntax

The loc function is used in concert with JITX syntax to apply the transform Pose to a particular instance. The general form of this syntax is:

at <Pose> [on <Side>]

In this example &#60;> is denoting an instance of this type of object. The [] denote optional phrases in the localization syntax.

  • The Pose instance following the at operator is required.
  • The Side following the on operator is an optional phrase. can move this instance to either the Top or Bottom side of the PCB. See Side. By default, the Top side is used.

Example Localization Syntax

Example for pad instances in a pcb-landpattern:

pcb-pad example-pad :
  name  = "Example Circle Pad"
  type  = SMD
  shape = Circle(1.0)
  layer(SolderMask(Top)) = Circle(1.2)

pcb-landpattern example-lp :
  description = "Land Pattern Demonstrating use of 'loc' for a Pad"

  pad p[1] : example-pad at loc(2.0, 3.0)
  pad p[2] : example-pad at loc(2.0, 3.0) on Bottom

Example for component instances in a pcb-module:

pcb-module example-mod :
  description = "Simple Module Demonstrating Placement"
  inst R1 : res-strap(10.0e3)
  place(R1) at loc(0.5, 0.5) on Top

Relative-To for Component Instances

For pcb-module, there is a relative-to operator for defining placements relative to other instances. This does not apply to pcb-landpattern for defining pads.

Example:

pcb-module example-mod :
  inst R1 : res-strap(10.0e3)
  place(R1) at loc(0.5, 0.5) on Top

  inst R2 : res-strap(100.0e3)
  place(R2) at loc(2.0, 3.0) on Top (relative-to R1)

In this case, R2 will be placed at the location (2.5, 3.5) in the example-mod coordinate frame.

Summary

Pose

Transformation Type

Functions

Function Description
loc (+ 8)
inverse
Pose Mirroring Operations
sub-angle
side
flip

Definitions

Pose

Transformation Type

public defstruct Pose <: Equalable & Hashable & HasMetaUtils
    angle: Double
    center: Point
    flip-x?: True|False

  • angle: Double - Rotation of the coordinate frame in degrees. This rotation applies at the origin of the coordinate frame defined by the center translate.

  • center: Point - Translation of the coordinate frame in X,Y

  • flip-x?: True|False - Mirror the coordinate frame across the Y axis. This is effectively a scaling operation that applies -1.0 * x to the points under transformation.

Instances of this type define a coordinate transformation Typically the user would not instantiate this directly, but would instead use the loc function.

The transformation consists of 3 operations applied in order:

  1. Flip - Flip across the Y-Axis of the current coordinate frame.
  2. Rotate - Rotate around the origin of the current coordinate frame.
  3. Translate - Move the origin of the current coordinate frame resulting in a new coordinate frame.

Functions

loc

public defn loc (center:Point, angle:Double, flip-x?:True|False) -> Pose

  • Returns Pose

loc

public defn loc (center:Point, angle:Double, flip:Flip) -> Pose

  • Returns Pose

loc

public defn loc (center:Point, angle:Double) -> Pose

  • Returns Pose

loc

public defn loc (center:Point, flip:Flip) -> Pose

  • Returns Pose

loc

public defn loc (center:Point) -> Pose

  • Returns Pose

loc

public defn loc (x:Double, y:Double, angle:Double, flip:Flip) -> Pose

  • Returns Pose

loc

public defn loc (x:Double, y:Double, angle:Double) -> Pose

  • Returns Pose

loc

public defn loc (x:Double, y:Double, flip:Flip) -> Pose

  • Returns Pose

loc

public defn loc (x:Double, y:Double) -> Pose

  • Returns Pose

inverse

public defn inverse (p:Pose) -> Pose

  • Returns Pose

Pose

Mirroring Operations

public defn Pose (center:Point, angle:Double, flip-x?:True|False) -> Pose

  • Returns Pose

This provides a convenient method of applying flip transformations across the X axis, the Y axis, or the XY diagonal axis.

sub-angle

public defn sub-angle (p:Pose, angle:Double) -> Pose

  • Returns Pose

side

public defn side (p:Pose) -> Side

  • Returns Side

flip

public defn flip (p:Pose) -> Flip

  • Returns Flip

Related Packages

Forwarded by package: jitx