Source file src/pkg/image/names.go

// Copyright 2010 The Go Authors. All rights reserved.
// Use of this source code is governed by a BSD-style
// license that can be found in the LICENSE file.

package image

// Colors from the HTML 4.01 specification: http://www.w3.org/TR/REC-html40/types.html#h-6.5
// These names do not necessarily match those from other lists, such as the X11 color names.
var (
    Aqua    = ColorImage{RGBAColor{0x00, 0xff, 0xff, 0xff}}
    Black   = ColorImage{RGBAColor{0x00, 0x00, 0x00, 0xff}}
    Blue    = ColorImage{RGBAColor{0x00, 0x00, 0xff, 0xff}}
    Fuchsia = ColorImage{RGBAColor{0xff, 0x00, 0xff, 0xff}}
    Gray    = ColorImage{RGBAColor{0x80, 0x80, 0x80, 0xff}}
    Green   = ColorImage{RGBAColor{0x00, 0x80, 0x00, 0xff}}
    Lime    = ColorImage{RGBAColor{0x00, 0xff, 0x00, 0xff}}
    Maroon  = ColorImage{RGBAColor{0x80, 0x00, 0x00, 0xff}}
    Navy    = ColorImage{RGBAColor{0x00, 0x00, 0x80, 0xff}}
    Olive   = ColorImage{RGBAColor{0x80, 0x80, 0x00, 0xff}}
    Red     = ColorImage{RGBAColor{0xff, 0x00, 0x00, 0xff}}
    Purple  = ColorImage{RGBAColor{0x80, 0x00, 0x80, 0xff}}
    Silver  = ColorImage{RGBAColor{0xc0, 0xc0, 0xc0, 0xff}}
    Teal    = ColorImage{RGBAColor{0x00, 0x80, 0x80, 0xff}}
    White   = ColorImage{RGBAColor{0xff, 0xff, 0xff, 0xff}}
    Yellow  = ColorImage{RGBAColor{0xff, 0xff, 0x00, 0xff}}

    // These synonyms are not in HTML 4.01.
    Cyan    = Aqua
    Magenta = Fuchsia
)

// A ColorImage is a practically infinite-sized Image of uniform Color.
// It implements both the Color and Image interfaces.
type ColorImage struct {
    C Color
}

func (c ColorImage) RGBA() (r, g, b, a uint32) {
    return c.C.RGBA()
}

func (c ColorImage) ColorModel() ColorModel {
    return ColorModelFunc(func(Color) Color { return c.C })
}

func (c ColorImage) Width() int { return 1e9 }

func (c ColorImage) Height() int { return 1e9 }

func (c ColorImage) At(x, y int) Color { return c.C }

// Opaque scans the entire image and returns whether or not it is fully opaque.
func (c ColorImage) Opaque() bool {
    _, _, _, a := c.C.RGBA()
    return a == 0xffff
}