93 lines
2.4 KiB
Go
93 lines
2.4 KiB
Go
// Copyright 2019 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 buffered
|
|
|
|
import (
|
|
"sync"
|
|
"sync/atomic"
|
|
)
|
|
|
|
var (
|
|
// delayedCommands represents a queue for image operations that are ordered before the game starts
|
|
// (BeginFrame). Before the game starts, the package shareable doesn't determine the minimum/maximum texture
|
|
// sizes (#879).
|
|
delayedCommands = []func() error{}
|
|
|
|
delayedCommandsM sync.Mutex
|
|
delayedCommandsFlushed uint32
|
|
)
|
|
|
|
func flushDelayedCommands() error {
|
|
fs := getDelayedFuncsAndClear()
|
|
for _, f := range fs {
|
|
if err := f(); err != nil {
|
|
return err
|
|
}
|
|
}
|
|
return nil
|
|
|
|
}
|
|
|
|
func getDelayedFuncsAndClear() []func() error {
|
|
if atomic.LoadUint32(&delayedCommandsFlushed) == 0 {
|
|
// Outline the slow-path to expect the fast-path is inlined.
|
|
return getDelayedFuncsAndClearSlow()
|
|
}
|
|
return nil
|
|
}
|
|
|
|
func getDelayedFuncsAndClearSlow() []func() error {
|
|
delayedCommandsM.Lock()
|
|
defer delayedCommandsM.Unlock()
|
|
|
|
if delayedCommandsFlushed == 0 {
|
|
defer atomic.StoreUint32(&delayedCommandsFlushed, 1)
|
|
|
|
fs := make([]func() error, len(delayedCommands))
|
|
copy(fs, delayedCommands)
|
|
delayedCommands = nil
|
|
return fs
|
|
}
|
|
|
|
return nil
|
|
}
|
|
|
|
// maybeCanAddDelayedCommand returns false if the delayed commands cannot be added.
|
|
// Otherwise, maybeCanAddDelayedCommand's returning value is not determined.
|
|
// For example, maybeCanAddDelayedCommand can return true even when flusing is being processed.
|
|
func maybeCanAddDelayedCommand() bool {
|
|
return atomic.LoadUint32(&delayedCommandsFlushed) == 0
|
|
}
|
|
|
|
func tryAddDelayedCommand(f func() error) bool {
|
|
delayedCommandsM.Lock()
|
|
defer delayedCommandsM.Unlock()
|
|
|
|
if delayedCommandsFlushed == 0 {
|
|
delayedCommands = append(delayedCommands, func() error {
|
|
return f()
|
|
})
|
|
return true
|
|
}
|
|
|
|
return false
|
|
}
|
|
|
|
func checkDelayedCommandsFlushed(fname string) {
|
|
if atomic.LoadUint32(&delayedCommandsFlushed) == 0 {
|
|
panic("buffered: the command queue is not available yet at " + fname)
|
|
}
|
|
}
|