commit b91b989d922ef4262e58bb23c04a07b92dd26480
author Courtney Goeltzenleuchter <courtneygo@google.com> Tue Oct 23 16:28:00 2018 -0600
committer Courtney Goeltzenleuchter <courtneygo@google.com> Tue Oct 30 08:18:13 2018 -0600
tree 434148e6b832865853a2e1840ef328b31a2556a5
parent 734a485ff4579ba520802672f4f864ded03b0ff1

Only load native EGL library if using GL back-end

In line with recently adjusted goals, remove application support
for specifying the ANGLE backend. That allows us to move the
backend property check into the Loader and only load the native
EGL library if the backend property indicates so.
Bug: 80239516
Test: manual, verify log only shows native library loaded when
ANGLE GL backend is selected.
    Select application to use ANGLE via Developer options
    adb shell setprop debug.angle.backend 0
    Start app.
    Review logs for "libEGL Loaded: libEGL_<native_library>.so

Change-Id: Ifae9b62ecf6723583bd461305f5a7e95910cfa43

opengl/libs/EGL/Loader.cpp

diff --git a/opengl/libs/EGL/Loader.cpp b/opengl/libs/EGL/Loader.cpp
index 9f39438..6624976 100644
--- a/opengl/libs/EGL/Loader.cpp
+++ b/opengl/libs/EGL/Loader.cpp
@@ -36,6 +36,7 @@
 #include "egl_platform_entries.h"
 #include "egl_trace.h"
 #include "egldefs.h"
+#include <EGL/eglext_angle.h>
 
 extern "C" {
   android_namespace_t* android_get_exported_namespace(const char*);
@@ -621,13 +622,30 @@
     if (so) {
         ALOGV("Loaded ANGLE %s library for %s (instead of native)",
               kind, app_name ? app_name : "nullptr");
-        property_get("debug.angle.backend", prop, "UNSET");
-        ALOGV("ANGLE's backend set to %s", prop);
         property_get("debug.hwui.renderer", prop, "UNSET");
         ALOGV("Skia's renderer set to %s", prop);
         cnx->useAngle = true;
-        // Find and load vendor libEGL for ANGLE
-        if (!cnx->vendorEGL) {
+
+        EGLint angleBackendDefault = EGL_PLATFORM_ANGLE_TYPE_VULKAN_ANGLE;
+
+        char prop[PROPERTY_VALUE_MAX];
+        property_get("debug.angle.backend", prop, "0");
+        switch (atoi(prop)) {
+            case 1:
+                ALOGV("%s: Requesting OpenGLES back-end", __FUNCTION__);
+                angleBackendDefault = EGL_PLATFORM_ANGLE_TYPE_OPENGLES_ANGLE;
+                break;
+            case 2:
+                ALOGV("%s: Requesting Vulkan back-end", __FUNCTION__);
+                angleBackendDefault = EGL_PLATFORM_ANGLE_TYPE_VULKAN_ANGLE;
+                break;
+            default:
+                break;
+        }
+
+        cnx->angleBackend = angleBackendDefault;
+        if (!cnx->vendorEGL && (cnx->angleBackend == EGL_PLATFORM_ANGLE_TYPE_OPENGLES_ANGLE)) {
+            // Find and load vendor libEGL for ANGLE's GL back-end to use.
             cnx->vendorEGL = load_system_driver("EGL");
         }
         return so;