From f196a877e6ff791ba7dd2e138e538756acd2e189 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Henrik=20Rydg=C3=A5rd?= <hrydgard@gmail.com>
Date: Sat, 3 Mar 2018 00:00:18 +0100
Subject: [PATCH] Android: Fix fallback from Vulkan to GL.

---
 android/jni/AndroidVulkanContext.cpp          |  9 +++++-
 android/jni/AndroidVulkanContext.h            |  4 ++-
 android/jni/app-android.cpp                   | 30 ++++++++++---------
 .../src/org/ppsspp/ppsspp/NativeActivity.java |  2 +-
 4 files changed, 28 insertions(+), 17 deletions(-)

diff --git a/android/jni/AndroidVulkanContext.cpp b/android/jni/AndroidVulkanContext.cpp
index 04481b3377..e5f4987920 100644
--- a/android/jni/AndroidVulkanContext.cpp
+++ b/android/jni/AndroidVulkanContext.cpp
@@ -72,12 +72,15 @@ static VKAPI_ATTR VkBool32 VKAPI_CALL Vulkan_Dbg(VkDebugReportFlagsEXT msgFlags,
 	return false;
 }
 
+AndroidVulkanContext::AndroidVulkanContext() {
+}
+
 AndroidVulkanContext::~AndroidVulkanContext() {
 	delete g_Vulkan;
 	g_Vulkan = nullptr;
 }
 
-bool AndroidVulkanContext::InitFromRenderThread(ANativeWindow *wnd, int desiredBackbufferSizeX, int desiredBackbufferSizeY, int backbufferFormat, int androidVersion) {
+bool AndroidVulkanContext::InitAPI() {
 	ILOG("AndroidVulkanContext::Init");
 	init_glslang();
 
@@ -124,6 +127,10 @@ bool AndroidVulkanContext::InitFromRenderThread(ANativeWindow *wnd, int desiredB
 		g_Vulkan = nullptr;
 		return false;
 	}
+	return true;
+}
+
+bool AndroidVulkanContext::InitFromRenderThread(ANativeWindow *wnd, int desiredBackbufferSizeX, int desiredBackbufferSizeY, int backbufferFormat, int androidVersion) {
 	int width = desiredBackbufferSizeX;
 	int height = desiredBackbufferSizeY;
 	if (!width || !height) {
diff --git a/android/jni/AndroidVulkanContext.h b/android/jni/AndroidVulkanContext.h
index 2c65de11c3..affc330157 100644
--- a/android/jni/AndroidVulkanContext.h
+++ b/android/jni/AndroidVulkanContext.h
@@ -8,9 +8,11 @@ class VulkanContext;
 
 class AndroidVulkanContext : public AndroidGraphicsContext {
 public:
-	AndroidVulkanContext() : draw_(nullptr) {}
+	AndroidVulkanContext();
 	~AndroidVulkanContext();
 
+	bool InitAPI();
+
 	bool InitFromRenderThread(ANativeWindow *wnd, int desiredBackbufferSizeX, int desiredBackbufferSizeY, int backbufferFormat, int androidVersion) override;
 	void Shutdown() override;
 	void SwapInterval(int interval) override;
diff --git a/android/jni/app-android.cpp b/android/jni/app-android.cpp
index 1e54500f0f..ad91edae81 100644
--- a/android/jni/app-android.cpp
+++ b/android/jni/app-android.cpp
@@ -431,25 +431,33 @@ extern "C" void Java_org_ppsspp_ppsspp_NativeApp_init
 		NativeInit(2, argv, user_data_path.c_str(), externalDir.c_str(), cacheDir.c_str());
 	}
 
-	// Now that we've loaded config, set javaGL.
-	javaGL = NativeQueryConfig("androidJavaGL") == "true";
 
 retry:
+	// Now that we've loaded config, set javaGL.
+	javaGL = NativeQueryConfig("androidJavaGL") == "true";
 	switch (g_Config.iGPUBackend) {
 	case (int)GPUBackend::OPENGL:
-		ILOG("NativeApp.init() -- creating OpenGL context");
 		useCPUThread = true;
-		if (javaGL) {
-			graphicsContext = new AndroidJavaEGLGraphicsContext();
-		} else {
-			graphicsContext = new AndroidEGLGraphicsContext();
-		}
+		_assert_(javaGL);
+		ILOG("NativeApp.init() -- creating OpenGL context (JavaGL)");
+		graphicsContext = new AndroidJavaEGLGraphicsContext();
 		break;
 	case (int)GPUBackend::VULKAN:
+	{
 		ILOG("NativeApp.init() -- creating Vulkan context");
 		useCPUThread = false;  // The Vulkan render manager manages its own thread.
 		// We create and destroy the Vulkan graphics context in the "EGL" thread.
+		AndroidVulkanContext *ctx = new AndroidVulkanContext();
+		if (!ctx->InitAPI()) {
+			ILOG("Failed to initialize Vulkan, switching to OpenGL");
+			g_Config.iGPUBackend = (int)GPUBackend::OPENGL;
+			SetGPUBackend(GPUBackend::OPENGL);
+			goto retry;
+		} else {
+			graphicsContext = ctx;
+		}
 		break;
+	}
 	default:
 		ELOG("NativeApp.init(): iGPUBackend %d not supported. Switching to OpenGL.", (int)g_Config.iGPUBackend);
 		g_Config.iGPUBackend = (int)GPUBackend::OPENGL;
@@ -931,12 +939,6 @@ retry:
 
 	int tries = 0;
 
-	_assert_msg_(G3D, !graphicsContext, "Graphics context already exists entering runEGLRenderLoop - this is wrong.");
-
-	if (vulkan) {
-		graphicsContext = new AndroidVulkanContext();
-	}
-
 	if (!graphicsContext->InitFromRenderThread(wnd, desiredBackbufferSizeX, desiredBackbufferSizeY, backbuffer_format, androidVersion)) {
 		ELOG("Failed to initialize graphics context.");
 
diff --git a/android/src/org/ppsspp/ppsspp/NativeActivity.java b/android/src/org/ppsspp/ppsspp/NativeActivity.java
index 01c2a107a1..30b25854a2 100644
--- a/android/src/org/ppsspp/ppsspp/NativeActivity.java
+++ b/android/src/org/ppsspp/ppsspp/NativeActivity.java
@@ -482,7 +482,7 @@ public abstract class NativeActivity extends Activity implements SurfaceHolder.C
 		gainAudioFocus(this.audioManager, this.audioFocusChangeListener);
         NativeApp.audioInit();
 
-	    if (javaGL) {
+        if (javaGL) {
 	        mGLSurfaceView = new NativeGLView(this);
 			nativeRenderer = new NativeRenderer(this);
 			mGLSurfaceView.setEGLContextClientVersion(2);