ebiten/shared.go
2018-03-03 20:50:26 +09:00

95 lines
2.2 KiB
Go

// Copyright 2018 The Ebiten 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 ebiten
import (
"github.com/hajimehoshi/ebiten/internal/bsp"
"github.com/hajimehoshi/ebiten/internal/restorable"
"github.com/hajimehoshi/ebiten/internal/sync"
)
type sharedImage struct {
restorable *restorable.Image
page bsp.Page
}
var (
theSharedImages = []*sharedImage{}
)
type sharedImagePart struct {
sharedImage *sharedImage
node *bsp.Node
}
func (s *sharedImagePart) image() *restorable.Image {
return s.sharedImage.restorable
}
func (s *sharedImagePart) region() (x, y, width, height int) {
return s.node.Region()
}
func (s *sharedImagePart) Dispose() {
s.sharedImage.page.Free(s.node)
if s.sharedImage.page.IsEmpty() {
s.sharedImage.restorable.Dispose()
s.sharedImage.restorable = nil
index := -1
for i, sh := range theSharedImages {
if sh == s.sharedImage {
index = i
break
}
}
if index == -1 {
panic("not reached")
}
theSharedImages = append(theSharedImages[:index], theSharedImages[index+1:]...)
}
}
var sharedImageLock sync.Mutex
func newSharedImagePart(width, height int) *sharedImagePart {
sharedImageLock.Lock()
sharedImageLock.Unlock()
if width > bsp.MaxSize || height > bsp.MaxSize {
return nil
}
for _, s := range theSharedImages {
if n := s.page.Alloc(width, height); n != nil {
return &sharedImagePart{
sharedImage: s,
node: n,
}
}
}
s := &sharedImage{
restorable: restorable.NewImage(bsp.MaxSize, bsp.MaxSize, false),
}
theSharedImages = append(theSharedImages, s)
n := s.page.Alloc(width, height)
if n == nil {
panic("not reached")
}
return &sharedImagePart{
sharedImage: s,
node: n,
}
}