Revert Android API_LEVEL change

glDispatchCompute requires Android API level 21, however bumping our
required minimum from 19 to 21 caused some clients' builds to fail.
Commenting-out that line for now to proceed with the 1.28.0 upgrade.

RELEASE_NOTES.md

@@ -28,6 +28,7 @@ A new header is inserted each time a *tag* is created.
 - Metal: newer devices are no longer limited to 16 samplers per Material.
 - gltfio: fix interpretation of occlusion strength
 - engine: minsdk is now 21 instead of 19. This allows the use of OpenGL ES 3.1
+- Vulkan: fix black screen regression
 
 ## v1.27.2
 

android/build.gradle

@@ -72,7 +72,7 @@ buildscript {
     }
 
     ext.versions = [
-        'minSdk': 21,
+        'minSdk': 19,
         'targetSdk': 33,
         'compileSdk': 33,
         'kotlin': '1.7.10',

android/samples/sample-gltf-viewer/build.gradle

@@ -30,7 +30,7 @@ android {
     compileSdkVersion versions.compileSdk
     defaultConfig {
         applicationId "com.google.android.filament.gltf"
-        minSdkVersion 21
+        minSdkVersion 19
         targetSdkVersion versions.targetSdk
         missingDimensionStrategy 'functionality', 'full'
     }

build/toolchain-arm7-linux-android.cmake

@@ -21,7 +21,7 @@ set(CMAKE_SYSTEM_NAME Linux)
 set(CMAKE_SYSTEM_VERSION 1)
 
 # android
-set(API_LEVEL 21)
+set(API_LEVEL 19)
 
 # architecture
 set(ARCH armv7a-linux-androideabi)

build/toolchain-x86-linux-android.cmake

@@ -21,7 +21,7 @@ set(CMAKE_SYSTEM_NAME Linux)
 set(CMAKE_SYSTEM_VERSION 1)
 
 # android
-set(API_LEVEL 21)
+set(API_LEVEL 19)
 
 # architecture
 set(ARCH i686-linux-android)

filament/backend/src/opengl/OpenGLDriver.cpp

@@ -3185,7 +3185,8 @@ void OpenGLDriver::dispatchCompute(Handle<HwProgram> program, math::uint3 workGr
     useProgram(p);
 
 #if defined(GL_ES_VERSION_3_1) || defined(GL_VERSION_4_3)
-    glDispatchCompute(workGroupCount.x, workGroupCount.y, workGroupCount.z);
+    // FIXME: this line is commented-out for now due to issues switching G3 clients to API 21.
+    // glDispatchCompute(workGroupCount.x, workGroupCount.y, workGroupCount.z);
 #endif
 
 #ifdef FILAMENT_ENABLE_MATDBG

filament/backend/src/opengl/platforms/PlatformEGLAndroid.cpp

@@ -35,9 +35,11 @@
 #include <jni.h>
 
 
-// We require filament to be built with a API 21 toolchain, before that, OpenGLES 3.1 didn't exist
-#if __ANDROID_API__ < 21
-#   error "__ANDROID_API__ must be at least 21"
+// We require filament to be built with a API 19 toolchain, before that, OpenGLES 3.0 didn't exist
+// Actually, OpenGL ES 3.0 was added to API 18, but API 19 is the better target and
+// the minimum for Jetpack at the time of this comment.
+#if __ANDROID_API__ < 19
+#   error "__ANDROID_API__ must be at least 19"
 #endif
 
 using namespace utils;