c2047754c3
Compiler changes:
* Change map assignment to use mapassign and assign value directly.
* Change string iteration to use decoderune, faster for ASCII strings.
* Change makeslice to take int, and use makeslice64 for larger values.
* Add new noverflow field to hmap struct used for maps.
Unresolved problems, to be fixed later:
* Commented out test in go/types/sizes_test.go that doesn't compile.
* Commented out reflect.TestStructOf test for padding after zero-sized field.
Reviewed-on: https://go-review.googlesource.com/35231
gotools/:
Updates for Go 1.8rc1.
* Makefile.am (go_cmd_go_files): Add bug.go.
(s-zdefaultcc): Write defaultPkgConfig.
* Makefile.in: Rebuild.
From-SVN: r244456
51 lines
1.1 KiB
Go
51 lines
1.1 KiB
Go
// Copyright 2016 The Go Authors. All rights reserved.
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// Use of this source code is governed by a BSD-style
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// license that can be found in the LICENSE file.
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// +build ignore
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package draw_test
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import (
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"fmt"
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"image"
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"image/color"
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"image/draw"
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"math"
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)
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func ExampleDrawer_floydSteinberg() {
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const width = 130
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const height = 50
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im := image.NewGray(image.Rectangle{Max: image.Point{X: width, Y: height}})
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for x := 0; x < width; x++ {
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for y := 0; y < height; y++ {
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dist := math.Sqrt(math.Pow(float64(x-width/2), 2)/3+math.Pow(float64(y-height/2), 2)) / (height / 1.5) * 255
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var gray uint8
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if dist > 255 {
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gray = 255
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} else {
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gray = uint8(dist)
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}
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im.SetGray(x, y, color.Gray{Y: 255 - gray})
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}
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}
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pi := image.NewPaletted(im.Bounds(), []color.Color{
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color.Gray{Y: 255},
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color.Gray{Y: 160},
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color.Gray{Y: 70},
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color.Gray{Y: 35},
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color.Gray{Y: 0},
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})
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draw.FloydSteinberg.Draw(pi, im.Bounds(), im, image.ZP)
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shade := []string{" ", "░", "▒", "▓", "█"}
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for i, p := range pi.Pix {
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fmt.Print(shade[p])
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if (i+1)%width == 0 {
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fmt.Print("\n")
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}
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}
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}
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