|
111
|
1 // Copyright 2010 The Go Authors. All rights reserved.
|
|
|
2 // Use of this source code is governed by a BSD-style
|
|
|
3 // license that can be found in the LICENSE file.
|
|
|
4
|
|
|
5 package image
|
|
|
6
|
|
|
7 import (
|
|
|
8 "image/color"
|
|
|
9 )
|
|
|
10
|
|
|
11 var (
|
|
|
12 // Black is an opaque black uniform image.
|
|
|
13 Black = NewUniform(color.Black)
|
|
|
14 // White is an opaque white uniform image.
|
|
|
15 White = NewUniform(color.White)
|
|
|
16 // Transparent is a fully transparent uniform image.
|
|
|
17 Transparent = NewUniform(color.Transparent)
|
|
|
18 // Opaque is a fully opaque uniform image.
|
|
|
19 Opaque = NewUniform(color.Opaque)
|
|
|
20 )
|
|
|
21
|
|
|
22 // Uniform is an infinite-sized Image of uniform color.
|
|
|
23 // It implements the color.Color, color.Model, and Image interfaces.
|
|
|
24 type Uniform struct {
|
|
|
25 C color.Color
|
|
|
26 }
|
|
|
27
|
|
|
28 func (c *Uniform) RGBA() (r, g, b, a uint32) {
|
|
|
29 return c.C.RGBA()
|
|
|
30 }
|
|
|
31
|
|
|
32 func (c *Uniform) ColorModel() color.Model {
|
|
|
33 return c
|
|
|
34 }
|
|
|
35
|
|
|
36 func (c *Uniform) Convert(color.Color) color.Color {
|
|
|
37 return c.C
|
|
|
38 }
|
|
|
39
|
|
|
40 func (c *Uniform) Bounds() Rectangle { return Rectangle{Point{-1e9, -1e9}, Point{1e9, 1e9}} }
|
|
|
41
|
|
|
42 func (c *Uniform) At(x, y int) color.Color { return c.C }
|
|
|
43
|
|
|
44 // Opaque scans the entire image and reports whether it is fully opaque.
|
|
|
45 func (c *Uniform) Opaque() bool {
|
|
|
46 _, _, _, a := c.C.RGBA()
|
|
|
47 return a == 0xffff
|
|
|
48 }
|
|
|
49
|
|
|
50 func NewUniform(c color.Color) *Uniform {
|
|
|
51 return &Uniform{c}
|
|
|
52 }
|
