From d71eb2bf365d520cfa95d392c21bfa2411dd0f2b Mon Sep 17 00:00:00 2001
From: Stephen Saunders <srsaunders@rogers.com>
Date: Thu, 29 Jul 2021 00:10:13 -0400
Subject: [PATCH] Disable X11_XCB dependencies for Linux and macOS

---
 neo/CMakeLists.txt                       | 24 ++++++++++++------------
 neo/renderer/Vulkan/RenderBackend_VK.cpp |  6 +++---
 neo/sys/posix/posix_public.h             |  7 ++++---
 3 files changed, 19 insertions(+), 18 deletions(-)

diff --git a/neo/CMakeLists.txt b/neo/CMakeLists.txt
index 4d23fee6..117a765d 100644
--- a/neo/CMakeLists.txt
+++ b/neo/CMakeLists.txt
@@ -424,18 +424,18 @@ if(USE_VULKAN)
 	
 	# Eric: For use with SDL2/Vulkan
 	if(UNIX)
-		find_package(X11_XCB)
-		if(X11_XCB_FOUND)
-			add_definitions(-DHAVE_X11_XCB)
-			list(APPEND SUBSYSTEMS [X11])
-			# SRS - Added PKG_ preface to X11_XCB_INCLUDE_DIRS for OSX, not sure about UNIX
-			if(${CMAKE_SYSTEM_NAME} MATCHES "Darwin")
-				include_directories(${PKG_X11_XCB_INCLUDE_DIRS})
-			else()
-				include_directories(${X11_XCB_INCLUDE_DIRS})
-			endif()
-		endif()
-		add_definitions(-DVK_USE_PLATFORM_XLIB_KHR)
+        if (${CMAKE_SYSTEM_NAME} MATCHES "Linux" OR ${CMAKE_SYSTEM_NAME} MATCHES "Darwin")
+            # SRS - Do nothing here for Linux and OSX since SDL2 is used in place of platform-specific Vulkan
+        else()
+            find_package(X11_XCB)
+            if(X11_XCB_FOUND)
+                list(APPEND SUBSYSTEMS [X11])
+                include_directories(${X11_XCB_INCLUDE_DIR})
+                add_definitions(-DVK_USE_PLATFORM_XCB_KHR)
+            else()
+                message(FATAL_ERROR "Could not find XCB library!")
+            endif()
+        endif()
 	elseif(WIN32)
 		add_definitions(-DVK_USE_PLATFORM_WIN32_KHR)
 	endif()
diff --git a/neo/renderer/Vulkan/RenderBackend_VK.cpp b/neo/renderer/Vulkan/RenderBackend_VK.cpp
index a95c710f..c377b6d4 100644
--- a/neo/renderer/Vulkan/RenderBackend_VK.cpp
+++ b/neo/renderer/Vulkan/RenderBackend_VK.cpp
@@ -435,7 +435,7 @@ CreateSurface
 
 static void CreateSurface()
 {
-#ifdef _WIN32
+#if defined(VK_USE_PLATFORM_WIN32_KHR) // _WIN32
 	VkWin32SurfaceCreateInfoKHR createInfo = {};
 	createInfo.sType = VK_STRUCTURE_TYPE_WIN32_SURFACE_CREATE_INFO_KHR;
 	createInfo.hinstance = win32.hInstance;
@@ -459,7 +459,7 @@ static void CreateSurface()
 	{
 		idLib::FatalError( "Error while creating Vulkan surface: %s", SDL_GetError() );
 	}
-#else
+#else // defined(VK_USE_PLATFORM_XCB_KHR)
 	VkXcbSurfaceCreateInfoKHR createInfo = {};
 	createInfo.sType = VK_STRUCTURE_TYPE_XCB_SURFACE_CREATE_INFO_KHR;
 	createInfo.pNext = NULL;
@@ -468,7 +468,7 @@ static void CreateSurface()
 	createInfo.window = info.window;
 
 	ID_VK_CHECK( vkCreateXcbSurfaceKHR( vkcontext.instance, &createInfo, NULL, &vkcontext.surface ) );
-#endif // __linux__
+#endif  // UNIX-style platforms
 
 #endif  // _WIN32
 
diff --git a/neo/sys/posix/posix_public.h b/neo/sys/posix/posix_public.h
index 7c7ba169..ce90c3a2 100644
--- a/neo/sys/posix/posix_public.h
+++ b/neo/sys/posix/posix_public.h
@@ -31,7 +31,8 @@ If you have questions concerning this license or the applicable additional terms
 
 #include <signal.h>
 
-#ifdef USE_VULKAN
+// SRS - Not used on Linux/macOS since using SDL2
+#if defined(USE_VULKAN) && defined(VK_USE_PLATFORM_XCB_KHR)
 	#include <xcb/xcb.h>
 #endif
 
@@ -74,8 +75,8 @@ enum /*clk_id_t*/ clockid_t { CLOCK_REALTIME, CLOCK_MONOTONIC, CLOCK_MONOTONIC_R
 int clock_gettime( /*clk_id_t*/ clockid_t clock, struct timespec* tp );     // SRS - use APPLE clockid_t
 #endif
 
-// Eric: Not used on Linux since using SDL2
-#if 0 //defined(USE_VULKAN)
+// Eric: Not used on Linux/macOS since using SDL2
+#if defined(USE_VULKAN) && defined(VK_USE_PLATFORM_XCB_KHR)
 /* Struct that holds global xcb state for vulkan */
 typedef struct _posixInfo
 {