ebiten/internal/atlas/set.go

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// Copyright 2023 The Ebitengine Authors
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
package atlas
// smallImageSet is a set for images.
// smallImageSet uses a slice assuming the number of items is not so big (smaller than 100 or so).
// If the number of items is big, a map might be better than a slice.
type smallImageSet struct {
s []*Image
}
func (s *smallImageSet) add(image *Image) {
for _, img := range s.s {
if img == image {
return
}
}
s.s = append(s.s, image)
}
func (s *smallImageSet) remove(image *Image) {
for i, img := range s.s {
if img == image {
copy(s.s[i:], s.s[i+1:])
s.s[len(s.s)-1] = nil
s.s = s.s[:len(s.s)-1]
return
}
}
}
func (s *smallImageSet) forEach(f func(*Image)) {
for _, img := range s.s {
f(img)
}
}
func (s *smallImageSet) clear() {
for i := range s.s {
s.s[i] = nil
}
s.s = s.s[:0]
}