core

package
v0.0.7 Latest Latest
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 Go to latest Published: Apr 10, 2019 License: MIT Imports: 30 Imported by: 2

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Index

Constants

This section is empty.

Variables

View Source 
var (
	NearestNeighbor = canvas.NearestNeighbor

	Box = ResampleFilter{
		"box",
		0.5,
		func(x float64) float64 {
			if math.Abs(x) < 0.5 {
				return 1
			}
			return 0
		},
	}

	Linear = canvas.Linear

	Gaussian = ResampleFilter{
		"gaussian",
		1.0,
		func(x float64) float64 {
			x = math.Abs(x)
			if x < 1.0 {
				exp := 2.0
				x *= 2.0
				y := math.Pow(0.5, math.Pow(x, exp))
				base := math.Pow(0.5, math.Pow(2, exp))
				return (y - base) / (1 - base)
			}
			return 0
		},
	}

	MitchellNetravali = ResampleFilter{
		"mitchelnetravali",
		2.0,
		func(x float64) float64 {
			b := 1.0 / 3
			c := 1.0 / 3
			var w [4]float64
			x = math.Abs(x)

			if x < 1.0 {
				w[0] = 0
				w[1] = 6 - 2*b
				w[2] = (-18 + 12*b + 6*c) * x * x
				w[3] = (12 - 9*b - 6*c) * x * x * x
			} else if x <= 2.0 {
				w[0] = 8*b + 24*c
				w[1] = (-12*b - 48*c) * x
				w[2] = (6*b + 30*c) * x * x
				w[3] = (-b - 6*c) * x * x * x
			} else {
				return 0
			}

			return (w[0] + w[1] + w[2] + w[3]) / 6
		},
	}

	CatmullRom = ResampleFilter{
		"catmullrom",
		2.0,
		func(x float64) float64 {
			b := 0.0
			c := 0.5
			var w [4]float64
			x = math.Abs(x)

			if x < 1.0 {
				w[0] = 0
				w[1] = 6 - 2*b
				w[2] = (-18 + 12*b + 6*c) * x * x
				w[3] = (12 - 9*b - 6*c) * x * x * x
			} else if x <= 2.0 {
				w[0] = 8*b + 24*c
				w[1] = (-12*b - 48*c) * x
				w[2] = (6*b + 30*c) * x * x
				w[3] = (-b - 6*c) * x * x * x
			} else {
				return 0
			}

			return (w[0] + w[1] + w[2] + w[3]) / 6
		},
	}

	Lanczos = ResampleFilter{
		"lanczos",
		3.0,
		func(x float64) float64 {
			x = math.Abs(x)
			if x == 0 {
				return 1.0
			} else if x < 3.0 {
				return (3.0 * math.Sin(math.Pi*x) * math.Sin(math.Pi*(x/3.0))) / (math.Pi * math.Pi * x * x)
			}
			return 0.0
		},
	}

	Bartlett = ResampleFilter{
		"bartlett",
		3.0,
		func(x float64) float64 {
			x = math.Abs(x)
			if x < 3.0 {
				return sinc(x) * (3.0 - x) / 3.0
			}
			return 0
		},
	}

	Hermite = ResampleFilter{
		"hermite",
		1.0,
		func(x float64) float64 {
			x = math.Abs(x)
			if x < 1.0 {
				return bcspline(x, 0.0, 0.0)
			}
			return 0
		},
	}

	BSpline = ResampleFilter{
		"bspline",
		2.0,
		func(x float64) float64 {
			x = math.Abs(x)
			if x < 2.0 {
				return bcspline(x, 1.0, 0.0)
			}
			return 0
		},
	}

	Hann = ResampleFilter{
		"hann",
		3.0,
		func(x float64) float64 {
			x = math.Abs(x)
			if x < 3.0 {
				return sinc(x) * (0.5 + 0.5*math.Cos(math.Pi*x/3.0))
			}
			return 0
		},
	}

	Hamming = ResampleFilter{
		"hamming",
		3.0,
		func(x float64) float64 {
			x = math.Abs(x)
			if x < 3.0 {
				return sinc(x) * (0.54 + 0.46*math.Cos(math.Pi*x/3.0))
			}
			return 0
		},
	}

	Blackman = ResampleFilter{
		"blackman",
		3.0,
		func(x float64) float64 {
			x = math.Abs(x)
			if x < 3.0 {
				return sinc(x) * (0.42 - 0.5*math.Cos(math.Pi*x/3.0+math.Pi) + 0.08*math.Cos(2.0*math.Pi*x/3.0))
			}
			return 0
		},
	}

	Welch = ResampleFilter{
		"welch",
		3.0,
		func(x float64) float64 {
			x = math.Abs(x)
			if x < 3.0 {
				return sinc(x) * (1.0 - (x * x / 9.0))
			}
			return 0
		},
	}

	Cosine = ResampleFilter{
		"cosine",
		3.0,
		func(x float64) float64 {
			x = math.Abs(x)
			if x < 3.0 {
				return sinc(x) * math.Cos((math.Pi/2.0)*(x/3.0))
			}
			return 0
		},
	}

	ResampleFilters = []ResampleFilter{
		NearestNeighbor,
		Box,
		Linear,
		Gaussian,
		MitchellNetravali,
		CatmullRom,
		Lanczos,
		Bartlett,
		Hermite,
		BSpline,
		Hann,
		Hamming,
		Blackman,
		Welch,
		Cosine,
	}
)
View Source 
var (
	FontsHome  string
	FontsShare = "/usr/share/fonts"
)
View Source 
var Core cmdMap

A string key map of functions returning a flip.Command.

Functions

func Asset 

func Asset(name string) ([]byte, error)

Asset loads and returns the asset for the given name. It returns an error if the asset could not be found or could not be loaded.

func AssetDir 

func AssetDir(name string) ([]string, error)

AssetDir returns the file names below a certain directory embedded in the file by go-bindata. For example if you run go-bindata on data/... and data contains the following hierarchy: 

data/
  foo.txt
  img/
    a.png
    b.png

then AssetDir("data") would return []string{"foo.txt", "img"} AssetDir("data/img") would return []string{"a.png", "b.png"} AssetDir("foo.txt") and AssetDir("notexist") would return an error AssetDir("") will return []string{"data"}.

func AssetInfo 

func AssetInfo(name string) (os.FileInfo, error)

AssetInfo loads and returns the asset info for the given name. It returns an error if the asset could not be found or could not be loaded.

func AssetNames 

func AssetNames() []string

AssetNames returns the names of the assets.

func FontDirs 

func FontDirs(dirs string) []string

func MustAsset 

func MustAsset(name string) []byte

MustAsset is like Asset but panics when Asset would return an error. It simplifies safe initialization of global variables.

func NewCommand 

func NewCommand(group, tag, instruction string,
	prio int,
	ffn flagSetFunc,
	cfn cmdFunc,
	x ...execution) *command

func RestoreAsset 

func RestoreAsset(dir, name string) error

RestoreAsset restores an asset under the given directory

func RestoreAssets 

func RestoreAssets(dir, name string) error

RestoreAssets restores an asset under the given directory recursively

func ToColor 

func ToColor(model, value string) color.Color

func WriteText 

func WriteText(cv canvas.Canvas, o *Options) string

Given a canvas and instance of Options, will draw text to the canvas.

Types

type AlphaS 

type AlphaS []string

func (AlphaS) Len 

func (a AlphaS) Len() int

func (AlphaS) Less 

func (a AlphaS) Less(i, j int) bool

func (AlphaS) Swap 

func (a AlphaS) Swap(i, j int)

type BlendFunc 

type BlendFunc = canvas.BlendFunc

type ColorRGB 

type ColorRGB struct {
	R, G, B float64
}

func (ColorRGB) RGBA 

func (c ColorRGB) RGBA() (r, g, b, a uint32)

type Fonts 

type Fonts struct {
	// contains filtered or unexported fields
}
var LF *Fonts

local fonts

func NewFonts 

func NewFonts() *Fonts

func (*Fonts) Get 

func (f *Fonts) Get(k string) *truetype.Font

func (*Fonts) List 

func (f *Fonts) List() []string

func (*Fonts) Set 

func (f *Fonts) Set(name string, ft *truetype.Font) bool

func (*Fonts) SetByte 

func (f *Fonts) SetByte(name string, fb []byte) bool

func (*Fonts) SetDir 

func (f *Fonts) SetDir(paths ...string) error

func (*Fonts) SetPath 

func (f *Fonts) SetPath(name, path string) bool

func (*Fonts) TextFont 

func (f *Fonts) TextFont(k string,
	height, lineHeight float64,
	a align,
	c color.Color,
	o float64,
	wrap, anchor bool) *TextFont

type Options 

type Options struct {
	log.Logger
	*data.Vector
}

A package level Options struct consisting of a logger and a data.Vector. 

var CoreOptions *Options

A package level Options instance.

type Position 

type Position = canvas.BlendPosition

type RGBA164 

type RGBA164 = canvas.RGBA164

type ResampleFilter 

type ResampleFilter = canvas.ResampleFilter

type Text 

type Text struct {
	*TextBox
	*TextLocation
	*TextFont
	// contains filtered or unexported fields
}

func NewText 

func NewText(
	msg string,
	bw, bh int,
	lx, ly float64,
	font string,
	fontSize float64,
	fontColor color.Color,
	opacity float64,
	lineHeight float64,
	alignment string,
	wrap, anchor bool) *Text

func OptionsToText 

func OptionsToText(o *Options) *Text

Translates a set of Options to a Text instance.

func (*Text) DrawString 

func (t *Text) DrawString(i draw.Image)

func (*Text) DrawStringAnchored 

func (t *Text) DrawStringAnchored(i draw.Image)

func (*Text) DrawStringWrapped 

func (t *Text) DrawStringWrapped(i draw.Image)

func (*Text) Scrive 

func (t *Text) Scrive(d draw.Image)

func (*Text) String 

func (t *Text) String() string

type TextBox 

type TextBox struct {
	W, H int
}

func NewTextBox 

func NewTextBox(bw, bh int) *TextBox

func (*TextBox) Box 

func (t *TextBox) Box(d draw.Image) draw.Image

type TextFont 

type TextFont struct {
	font.Face
	// contains filtered or unexported fields
}

func (*TextFont) MeasureString 

func (t *TextFont) MeasureString(s string) (w, h float64)

type TextLocation 

type TextLocation struct {
	X, Y float64
}

func NewTextLocation 

func NewTextLocation(x, y float64) *TextLocation

func (*TextLocation) Locate 

func (t *TextLocation) Locate() fixed.Point26_6

func (*TextLocation) Point 

func (t *TextLocation) Point() image.Point

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