From d9f8f6a2d0e703b346b72694bc0437ad911feee0 Mon Sep 17 00:00:00 2001
From: Andreas Kling <kling@serenityos.org>
Date: Fri, 26 Mar 2021 19:53:49 +0100
Subject: [PATCH] WindowServer: Add an IPC call for taking a screenshot

This patch adds Messages::WindowServer::GetScreenBitmap. It returns the
currently displayed on-screen bitmap as-is, as a Gfx::ShareableBitmap.
---
 Userland/Services/WindowServer/ClientConnection.cpp | 6 ++++++
 Userland/Services/WindowServer/ClientConnection.h   | 1 +
 Userland/Services/WindowServer/Compositor.h         | 2 ++
 Userland/Services/WindowServer/WindowServer.ipc     | 2 ++
 4 files changed, 11 insertions(+)

diff --git a/Userland/Services/WindowServer/ClientConnection.cpp b/Userland/Services/WindowServer/ClientConnection.cpp
index aa1c756fa3..8975e76ccc 100644
--- a/Userland/Services/WindowServer/ClientConnection.cpp
+++ b/Userland/Services/WindowServer/ClientConnection.cpp
@@ -987,4 +987,10 @@ void ClientConnection::did_become_responsive()
     set_unresponsive(false);
 }
 
+OwnPtr<Messages::WindowServer::GetScreenBitmapResponse> ClientConnection::handle(const Messages::WindowServer::GetScreenBitmap&)
+{
+    auto& bitmap = Compositor::the().front_bitmap_for_screenshot({});
+    return make<Messages::WindowServer::GetScreenBitmapResponse>(bitmap.to_shareable_bitmap());
+}
+
 }
diff --git a/Userland/Services/WindowServer/ClientConnection.h b/Userland/Services/WindowServer/ClientConnection.h
index 6ee7fe7456..51b84e7b82 100644
--- a/Userland/Services/WindowServer/ClientConnection.h
+++ b/Userland/Services/WindowServer/ClientConnection.h
@@ -167,6 +167,7 @@ private:
     virtual OwnPtr<Messages::WindowServer::GetMouseAccelerationResponse> handle(const Messages::WindowServer::GetMouseAcceleration&) override;
     virtual OwnPtr<Messages::WindowServer::SetScrollStepSizeResponse> handle(const Messages::WindowServer::SetScrollStepSize&) override;
     virtual OwnPtr<Messages::WindowServer::GetScrollStepSizeResponse> handle(const Messages::WindowServer::GetScrollStepSize&) override;
+    virtual OwnPtr<Messages::WindowServer::GetScreenBitmapResponse> handle(const Messages::WindowServer::GetScreenBitmap&) override;
 
     Window* window_from_id(i32 window_id);
 
diff --git a/Userland/Services/WindowServer/Compositor.h b/Userland/Services/WindowServer/Compositor.h
index 01fb0e7b8e..01a1ac2612 100644
--- a/Userland/Services/WindowServer/Compositor.h
+++ b/Userland/Services/WindowServer/Compositor.h
@@ -76,6 +76,8 @@ public:
 
     void did_construct_window_manager(Badge<WindowManager>);
 
+    const Gfx::Bitmap& front_bitmap_for_screenshot(Badge<ClientConnection>) const { return *m_front_bitmap; }
+
 private:
     Compositor();
     void init_bitmaps();
diff --git a/Userland/Services/WindowServer/WindowServer.ipc b/Userland/Services/WindowServer/WindowServer.ipc
index 0e1b1cb89d..c621cd5488 100644
--- a/Userland/Services/WindowServer/WindowServer.ipc
+++ b/Userland/Services/WindowServer/WindowServer.ipc
@@ -123,5 +123,7 @@ endpoint WindowServer = 2
     SetScrollStepSize(u32 step_size) => ()
     GetScrollStepSize() => (u32 step_size)
 
+    GetScreenBitmap() => (Gfx::ShareableBitmap bitmap)
+
     Pong() =|
 }