mirror of
https://bitbucket.org/s_l_teichmann/mtsatellite
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43 lines
767 B
Go
43 lines
767 B
Go
// Copyright 2016 by Sascha L. Teichmann
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// Use of this source code is governed by the MIT license
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// that can be found in the LICENSE file.
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package common
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import (
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"bytes"
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"image"
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"sync"
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)
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type btPos struct {
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x int
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y int
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}
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type BaseTileHash struct {
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// XXX: Maybe use some kind of LRU cache instead?
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hashes map[btPos][]byte
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sync.Mutex
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}
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func NewBaseTileHash() *BaseTileHash {
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return &BaseTileHash{hashes: map[btPos][]byte{}}
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}
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func (bth *BaseTileHash) Update(x, y int, img image.Image) bool {
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hash := SHA1Image(img)
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key := btPos{x, y}
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bth.Lock()
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defer bth.Unlock()
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if old, found := bth.hashes[key]; found {
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equals := bytes.Equal(old, hash)
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if !equals {
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bth.hashes[key] = hash
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}
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return !equals
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}
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bth.hashes[key] = hash
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return true
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}
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