From 077aad9afd515a18422fdb77a724e90b2add6c7e Mon Sep 17 00:00:00 2001
From: Will S <willstott101@gmail.com>
Date: Mon, 13 Dec 2021 14:57:53 +0000
Subject: [PATCH] Remove MEDIAPIPE_OMIT_EGL_WINDOW_BIT flag, and autodetect

---
 mediapipe/gpu/gl_context_egl.cc | 58 +++++++++++++++++++--------------
 1 file changed, 33 insertions(+), 25 deletions(-)

diff --git a/mediapipe/gpu/gl_context_egl.cc b/mediapipe/gpu/gl_context_egl.cc
index 952469270..37d0ed310 100644
--- a/mediapipe/gpu/gl_context_egl.cc
+++ b/mediapipe/gpu/gl_context_egl.cc
@@ -67,6 +67,23 @@ static void EnsureEglThreadRelease() {
                       reinterpret_cast<void*>(0xDEADBEEF));
 }
 
+static std::array<EGLint, 16> MakeEglConfig(EGLint gl_version, EGLint buffer_type) {
+  return {
+      // clang-format off
+      EGL_RENDERABLE_TYPE, gl_version,
+      // Allow rendering to pixel buffers or directly to windows.
+      EGL_SURFACE_TYPE,
+      buffer_type,
+      EGL_RED_SIZE, 8,
+      EGL_GREEN_SIZE, 8,
+      EGL_BLUE_SIZE, 8,
+      EGL_ALPHA_SIZE, 8,  // if you need the alpha channel
+      EGL_DEPTH_SIZE, 16,  // if you need the depth buffer
+      EGL_NONE
+      // clang-format on
+  };
+}
+
 GlContext::StatusOrGlContext GlContext::Create(std::nullptr_t nullp,
                                                bool create_thread) {
   return Create(EGL_NO_CONTEXT, create_thread);
@@ -89,35 +106,26 @@ absl::Status GlContext::CreateContextInternal(EGLContext share_context,
                                               int gl_version) {
   CHECK(gl_version == 2 || gl_version == 3);
 
-  const EGLint config_attr[] = {
-      // clang-format off
-      EGL_RENDERABLE_TYPE, gl_version == 3 ? EGL_OPENGL_ES3_BIT_KHR
-                                           : EGL_OPENGL_ES2_BIT,
-      // Allow rendering to pixel buffers or directly to windows.
-      EGL_SURFACE_TYPE,
-#ifdef MEDIAPIPE_OMIT_EGL_WINDOW_BIT
-      EGL_PBUFFER_BIT,
-#else
-      EGL_WINDOW_BIT,
-#endif
-      EGL_RED_SIZE, 8,
-      EGL_GREEN_SIZE, 8,
-      EGL_BLUE_SIZE, 8,
-      EGL_ALPHA_SIZE, 8,  // if you need the alpha channel
-      EGL_DEPTH_SIZE, 16,  // if you need the depth buffer
-      EGL_NONE
-      // clang-format on
+  EGLint gl_version_flag = gl_version == 3 ? EGL_OPENGL_ES3_BIT_KHR : EGL_OPENGL_ES2_BIT;
+
+  std::vector<std::array<EGLint, 16>> configs{
+    MakeEglConfig(gl_version_flag, EGL_PBUFFER_BIT),
+    MakeEglConfig(gl_version_flag, EGL_WINDOW_BIT)
   };
 
-  // TODO: improve config selection.
   EGLint num_configs;
-  EGLBoolean success =
-      eglChooseConfig(display_, config_attr, &config_, 1, &num_configs);
-  if (!success) {
-    return ::mediapipe::UnknownErrorBuilder(MEDIAPIPE_LOC)
-           << "eglChooseConfig() returned error " << std::showbase << std::hex
-           << eglGetError();
+
+  for (auto cfg : configs) {
+    EGLBoolean success =
+        eglChooseConfig(display_, &cfg[0], &config_, 1, &num_configs);
+    if (!success) {
+      return ::mediapipe::UnknownErrorBuilder(MEDIAPIPE_LOC)
+             << "eglChooseConfig() returned error " << std::showbase << std::hex
+             << eglGetError();
+    }
+    if (num_configs) break;
   }
+
   if (!num_configs) {
     return mediapipe::UnknownErrorBuilder(MEDIAPIPE_LOC)
            << "eglChooseConfig() returned no matching EGL configuration for "