From 7adeb40ae1234ef8ff7224a839a0ad823ba21ed3 Mon Sep 17 00:00:00 2001
From: Brandon DeRosier <bdero@google.com>
Date: Wed, 22 Feb 2023 00:54:41 -0800
Subject: [PATCH] [Impeller] Add root dockspace to playgrounds

---
 impeller/playground/playground.cc | 8 +++++++-
 1 file changed, 7 insertions(+), 1 deletion(-)

diff --git a/impeller/playground/playground.cc b/impeller/playground/playground.cc
index 08800d55bb1b0..b0c76922c3154 100644
--- a/impeller/playground/playground.cc
+++ b/impeller/playground/playground.cc
@@ -195,7 +195,11 @@ bool Playground::OpenPlaygroundHere(
   fml::ScopedCleanupClosure destroy_imgui_context(
       []() { ImGui::DestroyContext(); });
   ImGui::StyleColorsDark();
-  ImGui::GetIO().IniFilename = nullptr;
+
+  auto& io = ImGui::GetIO();
+  io.IniFilename = nullptr;
+  io.ConfigFlags |= ImGuiConfigFlags_DockingEnable;
+  io.ConfigWindowsResizeFromEdges = true;
 
   auto window = reinterpret_cast<GLFWwindow*>(impl_->GetWindowHandle());
   if (!window) {
@@ -246,6 +250,8 @@ bool Playground::OpenPlaygroundHere(
         [render_callback,
          &renderer = renderer_](RenderTarget& render_target) -> bool {
       ImGui::NewFrame();
+      ImGui::DockSpaceOverViewport(ImGui::GetMainViewport(),
+                                   ImGuiDockNodeFlags_PassthruCentralNode);
       bool result = render_callback(render_target);
       ImGui::Render();