context_js.go 1.0 KB

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  1. // Copyright 2020 The Ebiten Authors
  2. //
  3. // Licensed under the Apache License, Version 2.0 (the "License");
  4. // you may not use this file except in compliance with the License.
  5. // You may obtain a copy of the License at
  6. //
  7. // http://www.apache.org/licenses/LICENSE-2.0
  8. //
  9. // Unless required by applicable law or agreed to in writing, software
  10. // distributed under the License is distributed on an "AS IS" BASIS,
  11. // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  12. // See the License for the specific language governing permissions and
  13. // limitations under the License.
  14. package main
  15. import (
  16. "fmt"
  17. "syscall/js"
  18. )
  19. func (g *Game) loseAndRestoreContext() {
  20. if g.lost {
  21. return
  22. }
  23. doc := js.Global().Get("document")
  24. canvas := doc.Call("getElementsByTagName", "canvas").Index(0)
  25. context := canvas.Call("getContext", "webgl2")
  26. ext := context.Call("getExtension", "WEBGL_lose_context")
  27. if !ext.Truthy() {
  28. fmt.Println("Fail to force context lost.")
  29. return
  30. }
  31. ext.Call("loseContext")
  32. fmt.Println("Lost the context!")
  33. g.lost = true
  34. }