display: Store and restore the current eglContext

Tone mapper engine setting the current eglContext and never
restored it.  With multiple eglContexts used in same thread
by SurfaceFlinger and GPU Tonemapper, it lead to incorrect
eglContexts being used, hence always store the restore the
eglContext in each GPUTonemapper call.

CRs-Fixed: 2009259
Change-Id: Ic9fe73818ddfe3881e5fa82f7853dce130bba24e

1 files changed, 21 insertions, 0 deletions

diff --git a/gpu_tonemapper/glengine.cpp b/gpu_tonemapper/glengine.cpp
index 7a970c5d..90fe5022 100644
--- a/gpu_tonemapper/glengine.cpp
+++ b/gpu_tonemapper/glengine.cpp
@@ -47,6 +47,27 @@ void engine_bind(void* context)
 }
 
 //-----------------------------------------------------------------------------
+// store the current context(caller)
+void* engine_backup()
+{
+  EngineContext* callerContext = new EngineContext();
+  // store the previous display/context
+  callerContext->eglDisplay = eglGetCurrentDisplay();
+  callerContext->eglContext = eglGetCurrentContext();
+  callerContext->eglSurface = eglGetCurrentSurface(EGL_DRAW);
+
+  return (void*)callerContext;
+}
+//-----------------------------------------------------------------------------
+// frees the backed up caller context
+void engine_free_backup(void* context)
+{
+  EngineContext* callerContext = (EngineContext*)(context);
+
+  delete callerContext;
+}
+
+//-----------------------------------------------------------------------------
 // initialize GL
 //
 void* engine_initialize()