Add SbWindowGetDisplayHandle to Starboard Windowing interface

cobalt/renderer/backend/egl/graphics_system.cc

@@ -139,9 +139,18 @@ GraphicsSystemEGL::GraphicsSystemEGL(
   glimp::SetTraceEventImplementation(&s_glimp_to_base_trace_event_bridge);
 #endif  // #if defined(ENABLE_GLIMP_TRACING)
 
+#if STARBOARD >= 16
+  display _ = SbWindowGetDisplayHandle(window_);
+  // Fall back to SB_EGL_DEFAULT_DISPLAY
+  if (SB_EGL_NO_DISPLAY != display_) {
+    display_ = EGL_CALL_SIMPLE(eglGetDisplay(SB_EGL_DEFAULT_DISPLAY));
+    SB_CHECK(SB_EGL_SUCCESS == EGL_CALL_SIMPLE(eglGetError()));
+  }
+#else
   display_ = EGL_CALL_SIMPLE(eglGetDisplay(EGL_DEFAULT_DISPLAY));
-  CHECK_NE(EGL_NO_DISPLAY, display_);
   CHECK_EQ(EGL_SUCCESS, EGL_CALL_SIMPLE(eglGetError()));
+#endif
+  CHECK_NE(EGL_NO_DISPLAY, display_);
 
   {
     // Despite eglTerminate() being used in the destructor, the current

starboard/CHANGELOG.md

@@ -9,6 +9,14 @@ since the version previous to it.
 
 ## Version 16
 
+
+### Added SbWindowGetDisplayHandle
+
+The function retrieves native EGL display handle, simplifying correct EGL
+context initialization on some platforms. This complements
+SbWindowGetPlatformHandle, which retrieves the native window handle.
+
+
 ### Added standard POSIX socket getaddrinfo/freeaddrinfo APIs.
 The standard API `getaddrinfo` and `freeaddrinfo`, can be used from
 <netdb.h>.

starboard/android/shared/BUILD.gn

@@ -257,6 +257,7 @@ static_library("starboard_platform") {
     "//starboard/shared/stub/thread_sampler_is_supported.cc",
     "//starboard/shared/stub/thread_sampler_thaw.cc",
     "//starboard/shared/stub/ui_nav_get_interface.cc",
+    "//starboard/shared/stub/window_get_display_handle.cc",
     "accessibility_get_caption_settings.cc",
     "accessibility_get_display_settings.cc",
     "accessibility_get_text_to_speech_settings.cc",

starboard/examples/glclear/main.cc

@@ -104,8 +104,17 @@ Application::Application() {
   window_ = SbWindowCreate(&options);
   SB_CHECK(SbWindowIsValid(window_));
 
+#if STARBOARD >= 16
+  display _ = SbWindowGetDisplayHandle(window_);
+  // Fall back to SB_EGL_DEFAULT_DISPLAY
+  if (SB_EGL_NO_DISPLAY != display_) {
+    display_ = EGL_CALL_SIMPLE(eglGetDisplay(SB_EGL_DEFAULT_DISPLAY));
+    SB_CHECK(SB_EGL_SUCCESS == EGL_CALL_SIMPLE(eglGetError()));
+  }
+#else
   display_ = EGL_CALL_SIMPLE(eglGetDisplay(SB_EGL_DEFAULT_DISPLAY));
   SB_CHECK(SB_EGL_SUCCESS == EGL_CALL_SIMPLE(eglGetError()));
+#endif
   SB_CHECK(SB_EGL_NO_DISPLAY != display_);
 
   EGL_CALL(eglInitialize(display_, NULL, NULL));

starboard/linux/x64x11/shared/BUILD.gn

@@ -41,6 +41,7 @@ static_library("starboard_platform_sources") {
     "//starboard/shared/x11/player_set_bounds.cc",
     "//starboard/shared/x11/window_create.cc",
     "//starboard/shared/x11/window_destroy.cc",
+    "//starboard/shared/x11/window_get_display_handle.cc",
     "//starboard/shared/x11/window_get_platform_handle.cc",
     "//starboard/shared/x11/window_get_size.cc",
     "//starboard/shared/x11/window_internal.cc",

starboard/nplb/BUILD.gn

@@ -264,6 +264,7 @@ target(gtest_target_type, "nplb") {
     "window_create_test.cc",
     "window_destroy_test.cc",
     "window_get_diagonal_size_in_inches_test.cc",
+    "window_get_display_handle_test.cc",
     "window_get_platform_handle_test.cc",
     "window_get_size_test.cc",
   ]

starboard/nplb/window_get_display_handle_test.cc

@@ -0,0 +1,44 @@
+// Copyright 2024 The Cobalt Authors. All Rights Reserved.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+#include <EGL/egl.h>
+#include "starboard/configuration.h"
+#include "starboard/window.h"
+#include "testing/gtest/include/gtest/gtest.h"
+
+#if SB_API_VERSION >= 16
+namespace starboard {
+namespace nplb {
+namespace {
+
+TEST(SbWindowGetDisplayHandleTest, SunnyDay) {
+  SbWindow window = SbWindowCreate(NULL);
+  ASSERT_TRUE(SbWindowIsValid(window));
+  void* handle = SbWindowGetDisplayHandle(window);
+  // 0 could actually be a valid value here, because we don't know what the
+  // platform uses as its native window handle type, so we can't do any
+  // verification here.
+  ASSERT_TRUE(SbWindowDestroy(window));
+}
+
+TEST(SbWindowGetDisplayHandleTest, RainyDay) {
+  void* handle = SbWindowGetDisplayHandle(kSbWindowInvalid);
+  ASSERT_EQ(handle, EGL_NO_DISPLAY);
+}
+
+}  // namespace
+}  // namespace nplb
+}  // namespace starboard
+
+#endif  // SB_API_VERSION >= 16

starboard/raspi/shared/BUILD.gn

@@ -324,6 +324,7 @@ static_library("starboard_platform_sources") {
     "//starboard/shared/stub/window_blur_on_screen_keyboard.cc",
     "//starboard/shared/stub/window_focus_on_screen_keyboard.cc",
     "//starboard/shared/stub/window_get_diagonal_size_in_inches.cc",
+    "//starboard/shared/stub/window_get_display_handle.cc",
     "//starboard/shared/stub/window_get_on_screen_keyboard_bounding_rect.cc",
     "//starboard/shared/stub/window_hide_on_screen_keyboard.cc",
     "//starboard/shared/stub/window_is_on_screen_keyboard_shown.cc",

starboard/shared/stub/window_get_display_handle.cc

@@ -0,0 +1,20 @@
+// Copyright 2024 The Cobalt Authors. All Rights Reserved.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+#include "starboard/window.h"
+
+void* SbWindowGetDisplayHandle(SbWindow window) {
+  // Resolves to EGL_NO_DISPLAY
+  return nullptr;
+}

starboard/shared/x11/window_get_display_handle.cc

@@ -0,0 +1,31 @@
+// Copyright 2024 The Cobalt Authors. All Rights Reserved.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+#include <EGL/egl.h>
+#include "starboard/window.h"
+
+#include "starboard/player.h"
+#include "starboard/shared/x11/window_internal.h"
+
+#if SB_API_VERSION >= 16
+
+void* SbWindowGetDisplayHandle(SbWindow window) {
+  if (!SbWindowIsValid(window)) {
+    return EGL_NO_DISPLAY;
+  }
+
+  return reinterpret_cast<void*>(window->display);
+}
+
+#endif  // SB_API_VERSION >= 16

starboard/stub/BUILD.gn

@@ -271,6 +271,7 @@ static_library("stub_sources") {
     "//starboard/shared/stub/window_destroy.cc",
     "//starboard/shared/stub/window_focus_on_screen_keyboard.cc",
     "//starboard/shared/stub/window_get_diagonal_size_in_inches.cc",
+    "//starboard/shared/stub/window_get_display_handle.cc",
     "//starboard/shared/stub/window_get_on_screen_keyboard_bounding_rect.cc",
     "//starboard/shared/stub/window_get_platform_handle.cc",
     "//starboard/shared/stub/window_get_size.cc",

starboard/win/shared/BUILD.gn

@@ -138,6 +138,7 @@ static_library("starboard_platform") {
     "//starboard/shared/stub/window_blur_on_screen_keyboard.cc",
     "//starboard/shared/stub/window_focus_on_screen_keyboard.cc",
     "//starboard/shared/stub/window_get_diagonal_size_in_inches.cc",
+    "//starboard/shared/stub/window_get_display_handle.cc",
     "//starboard/shared/stub/window_get_on_screen_keyboard_bounding_rect.cc",
     "//starboard/shared/stub/window_hide_on_screen_keyboard.cc",
     "//starboard/shared/stub/window_is_on_screen_keyboard_shown.cc",

starboard/window.h

@@ -137,6 +137,16 @@ SB_EXPORT bool SbWindowGetSize(SbWindow window, SbWindowSize* size);
 // |window|: The SbWindow to retrieve the platform handle for.
 SB_EXPORT void* SbWindowGetPlatformHandle(SbWindow window);
 
+#if SB_API_VERSION >= 16
+// Gets the platform-specific handle for |display|, which can be passed as an
+// EGLNativeDisplayType to initialize EGL/GLES. This return value is entirely
+// platform-specific.
+// A return value of EGL_NO_DISPLAY means failure.
+//
+// |window|: The SbWindow to retrieve the platform display handle for.
+SB_EXPORT void* SbWindowGetDisplayHandle(SbWindow window);
+#endif
+
 // System-triggered OnScreenKeyboard events have ticket value
 // kSbEventOnScreenKeyboardInvalidTicket.
 #define kSbEventOnScreenKeyboardInvalidTicket (-1)