smarter gl config selection

app/src/main/java/com/geode/launcher/GeometryDashActivity.kt

@@ -5,6 +5,7 @@ import android.content.Intent
 import android.content.pm.ActivityInfo
 import android.content.pm.ApplicationInfo
 import android.content.pm.PackageInfo
+import android.opengl.GLSurfaceView
 import android.os.Build
 import android.os.Bundle
 import android.os.Environment
@@ -39,6 +40,9 @@ import java.io.File
 import java.io.FileInputStream
 import java.io.FileOutputStream
 import java.io.IOException
+import javax.microedition.khronos.egl.EGL10
+import javax.microedition.khronos.egl.EGLConfig
+import javax.microedition.khronos.egl.EGLDisplay
 
 enum class DisplayMode {
     DEFAULT, LIMITED, FULLSCREEN;
@@ -61,7 +65,6 @@ fun ratioForPreference(value: String) = when (value) {
 
 class GeometryDashActivity : AppCompatActivity(), Cocos2dxHelper.Cocos2dxHelperListener, GeodeUtils.CapabilityListener {
     private var mGLSurfaceView: Cocos2dxGLSurfaceView? = null
-    private val sTag = GeometryDashActivity::class.simpleName
     private var mIsRunning = false
     private var mIsOnPause = false
     private var mHasWindowFocus = false
@@ -419,11 +422,7 @@ class GeometryDashActivity : AppCompatActivity(), Cocos2dxHelper.Cocos2dxHelperL
         }
 
         glSurfaceView.setEGLContextClientVersion(2)
-        glSurfaceView.setEGLConfigChooser(5, 6, 5, 0, 16, 8)
-
-        if (isAndroidEmulator()) {
-            glSurfaceView.setEGLConfigChooser(8, 8, 8, 8, 16, 0)
-        }
+        glSurfaceView.setEGLConfigChooser(EGLConfigChooser())
 
         glSurfaceView.initView()
 
@@ -567,18 +566,6 @@ class GeometryDashActivity : AppCompatActivity(), Cocos2dxHelper.Cocos2dxHelperL
         TODO("Not yet implemented")
     }
 
-    private fun isAndroidEmulator(): Boolean {
-        Log.d(sTag, "model=" + Build.MODEL)
-        val product = Build.PRODUCT
-        Log.d(sTag, "product=$product")
-        var isEmulator = false
-        if (product != null) {
-            isEmulator = product == "sdk" || product.contains("_sdk") || product.contains("sdk_")
-        }
-        Log.d(sTag, "isEmulator=$isEmulator")
-        return isEmulator
-    }
-
     override fun onCapabilityAdded(capability: String): Boolean {
         return when (capability) {
             GeodeUtils.CAPABILITY_EXTENDED_INPUT -> {
@@ -602,7 +589,7 @@ class GeometryDashActivity : AppCompatActivity(), Cocos2dxHelper.Cocos2dxHelperL
 
         val modListing = try {
             assets.list(internalModBase)
-        } catch (ioe: IOException) {
+        } catch (_: IOException) {
             emptyArray<String>()
         }
 
@@ -624,4 +611,78 @@ class GeometryDashActivity : AppCompatActivity(), Cocos2dxHelper.Cocos2dxHelperL
             }
         }
     }
+
+    class EGLConfigChooser : GLSurfaceView.EGLConfigChooser {
+        // this comes from EGL14, but is unavailable on EGL10
+        // also EGL14 is incompatible with EGL10. so whatever
+        private var EGL_OPENGL_ES2_BIT: Int = 0x04
+
+        private data class ConfigValues(
+            val redSize: Int,
+            val greenSize: Int,
+            val blueSize: Int,
+            val alphaSize: Int,
+            val depthSize: Int,
+            val stencilSize: Int,
+        )
+
+        private fun getAttribValue(egl: EGL10, display: EGLDisplay, config: EGLConfig, attrib: Int): Int {
+            val value = IntArray(1)
+            egl.eglGetConfigAttrib(display, config, attrib, value)
+
+            return value[0]
+        }
+
+        private fun testConfig(egl: EGL10, display: EGLDisplay, attrib: ConfigValues): EGLConfig? {
+            val attribList = intArrayOf(
+                EGL10.EGL_RENDERABLE_TYPE, EGL_OPENGL_ES2_BIT,
+                EGL10.EGL_RED_SIZE, attrib.redSize,
+                EGL10.EGL_GREEN_SIZE, attrib.greenSize,
+                EGL10.EGL_BLUE_SIZE, attrib.blueSize,
+                EGL10.EGL_ALPHA_SIZE, attrib.alphaSize,
+                EGL10.EGL_DEPTH_SIZE, attrib.depthSize,
+                EGL10.EGL_STENCIL_SIZE, attrib.stencilSize,
+                EGL10.EGL_NONE
+            )
+
+            val configs = arrayOfNulls<EGLConfig>(1)
+            val numConfigs = IntArray(1)
+
+            val res = egl.eglChooseConfig(display, attribList, configs, configs.size, numConfigs)
+            if (res && numConfigs[0] > 0 && configs[0] != null) {
+                return configs[0]
+            }
+
+            return null
+        }
+
+        private fun printConfig(egl: EGL10, display: EGLDisplay, config: EGLConfig) {
+            val id = getAttribValue(egl, display, config, EGL10.EGL_CONFIG_ID)
+            val red = getAttribValue(egl, display, config, EGL10.EGL_RED_SIZE)
+            val green = getAttribValue(egl, display, config, EGL10.EGL_GREEN_SIZE)
+            val blue = getAttribValue(egl, display, config, EGL10.EGL_BLUE_SIZE)
+            val alpha = getAttribValue(egl, display, config, EGL10.EGL_ALPHA_SIZE)
+            val depth = getAttribValue(egl, display, config, EGL10.EGL_DEPTH_SIZE)
+            val stencil = getAttribValue(egl, display, config, EGL10.EGL_STENCIL_SIZE)
+            println("EGLConfig $id: (red = $red, green = $green, blue = $blue, alpha = $alpha, depth = $depth, stencil = $stencil)")
+        }
+
+        override fun chooseConfig(egl: EGL10, display: EGLDisplay): EGLConfig {
+            val configs = listOf(
+                ConfigValues(8, 8, 8, 8, 16, 8),
+                ConfigValues(8, 8, 8, 0, 16, 8),
+                ConfigValues(5, 6, 5, 0, 16, 8),
+                ConfigValues(0, 0, 0, 0, 0, 0),
+            )
+
+            return configs.firstNotNullOf {
+                val config = testConfig(egl, display, it)
+                if (config != null) {
+                    printConfig(egl, display, config)
+                }
+
+                config
+            }
+        }
+    }
 }