Documentation

Overview

    Package f32 is a float32 implementation of package image's Point and Rectangle.

    The coordinate space has the origin in the top left corner with the axes extending right and down.

    Index

    Constants

    This section is empty.

    Variables

    This section is empty.

    Functions

    This section is empty.

    Types

    type Affine2D

    type Affine2D struct {
    	// contains filtered or unexported fields
    }

      Affine2D represents an affine 2D transformation. The zero value if Affine2D represents the identity transform.

      func NewAffine2D

      func NewAffine2D(sx, hx, ox, hy, sy, oy float32) Affine2D

        NewAffine2D creates a new Affine2D transform from the matrix elements in row major order. The rows are: [sx, hx, ox], [hy, sy, oy], [0, 0, 1].

        func (Affine2D) Elems

        func (a Affine2D) Elems() (sx, hx, ox, hy, sy, oy float32)

          Elems returns the matrix elements of the transform in row-major order. The rows are: [sx, hx, ox], [hy, sy, oy], [0, 0, 1].

          func (Affine2D) Invert

          func (a Affine2D) Invert() Affine2D

            Invert the transformation. Note that if the matrix is close to singular numerical errors may become large or infinity.

            func (Affine2D) Mul

            func (A Affine2D) Mul(B Affine2D) (r Affine2D)

              Mul returns A*B.

              func (Affine2D) Offset

              func (a Affine2D) Offset(offset Point) Affine2D

                Offset the transformation.

                func (Affine2D) Rotate

                func (a Affine2D) Rotate(origin Point, radians float32) Affine2D

                  Rotate the transformation by the given angle (in radians) counter clockwise around the given origin.

                  func (Affine2D) Scale

                  func (a Affine2D) Scale(origin, factor Point) Affine2D

                    Scale the transformation around the given origin.

                    func (Affine2D) Shear

                    func (a Affine2D) Shear(origin Point, radiansX, radiansY float32) Affine2D

                      Shear the transformation by the given angle (in radians) around the given origin.

                      func (Affine2D) String

                      func (a Affine2D) String() string

                      func (Affine2D) Transform

                      func (a Affine2D) Transform(p Point) Point

                        Transform p by returning a*p.

                        type Point

                        type Point struct {
                        	X, Y float32
                        }

                          A Point is a two dimensional point.

                          func Pt

                          func Pt(x, y float32) Point

                            Pt is shorthand for Point{X: x, Y: y}.

                            func (Point) Add

                            func (p Point) Add(p2 Point) Point

                              Add return the point p+p2.

                              func (Point) In

                              func (p Point) In(r Rectangle) bool

                                In reports whether p is in r.

                                func (Point) Mul

                                func (p Point) Mul(s float32) Point

                                  Mul returns p scaled by s.

                                  func (Point) String

                                  func (p Point) String() string

                                    String return a string representation of p.

                                    func (Point) Sub

                                    func (p Point) Sub(p2 Point) Point

                                      Sub returns the vector p-p2.

                                      type Rectangle

                                      type Rectangle struct {
                                      	Min, Max Point
                                      }

                                        A Rectangle contains the points (X, Y) where Min.X <= X < Max.X, Min.Y <= Y < Max.Y.

                                        func Rect

                                        func Rect(x0, y0, x1, y1 float32) Rectangle

                                          Rect is a shorthand for Rectangle{Point{x0, y0}, Point{x1, y1}}. The returned Rectangle has x0 and y0 swapped if necessary so that it's correctly formed.

                                          func (Rectangle) Add

                                          func (r Rectangle) Add(p Point) Rectangle

                                            Add offsets r with the vector p.

                                            func (Rectangle) Canon

                                            func (r Rectangle) Canon() Rectangle

                                              Canon returns the canonical version of r, where Min is to the upper left of Max.

                                              func (Rectangle) Dx

                                              func (r Rectangle) Dx() float32

                                                Dx returns r's width.

                                                func (Rectangle) Dy

                                                func (r Rectangle) Dy() float32

                                                  Dy returns r's Height.

                                                  func (Rectangle) Empty

                                                  func (r Rectangle) Empty() bool

                                                    Empty reports whether r represents the empty area.

                                                    func (Rectangle) Intersect

                                                    func (r Rectangle) Intersect(s Rectangle) Rectangle

                                                      Intersect returns the intersection of r and s.

                                                      func (Rectangle) Size

                                                      func (r Rectangle) Size() Point

                                                        Size returns r's width and height.

                                                        func (Rectangle) String

                                                        func (r Rectangle) String() string

                                                          String return a string representation of r.

                                                          func (Rectangle) Sub

                                                          func (r Rectangle) Sub(p Point) Rectangle

                                                            Sub offsets r with the vector -p.

                                                            func (Rectangle) Union

                                                            func (r Rectangle) Union(s Rectangle) Rectangle

                                                              Union returns the union of r and s.

                                                              Source Files