From e3cfe9f009ff9a92f1cd02aa2017e94a5b8ee686 Mon Sep 17 00:00:00 2001
From: Wojtek Figat <wojtek@figat.pl>
Date: Tue, 17 Jan 2023 15:34:45 +0100
Subject: [PATCH] Add support for using system-installed Vulkan SDK on Linux

---
 .../Vulkan/GraphicsDeviceVulkan.Build.cs      | 36 +++++++++++++------
 1 file changed, 26 insertions(+), 10 deletions(-)

diff --git a/Source/Engine/GraphicsDevice/Vulkan/GraphicsDeviceVulkan.Build.cs b/Source/Engine/GraphicsDevice/Vulkan/GraphicsDeviceVulkan.Build.cs
index c56619a0f..b2780f7ca 100644
--- a/Source/Engine/GraphicsDevice/Vulkan/GraphicsDeviceVulkan.Build.cs
+++ b/Source/Engine/GraphicsDevice/Vulkan/GraphicsDeviceVulkan.Build.cs
@@ -40,20 +40,29 @@ public sealed class VulkanSdk : Sdk
             return;
 
         var vulkanSdk = Environment.GetEnvironmentVariable("VULKAN_SDK");
-        if (platform == TargetPlatform.Mac && (vulkanSdk == null || !Directory.Exists(vulkanSdk)))
+        if (vulkanSdk == null || !Directory.Exists(vulkanSdk))
         {
-            // Try to guess install location for the current user
-            var path = Path.Combine(Environment.GetFolderPath(Environment.SpecialFolder.UserProfile), "VulkanSDK");
-            if (Directory.Exists(path))
+            if (platform == TargetPlatform.Mac)
             {
-                var subDirs = Directory.GetDirectories(path);
-                if (subDirs.Length != 0)
+                // Try to guess install location for the current user
+                var path = Path.Combine(Environment.GetFolderPath(Environment.SpecialFolder.UserProfile), "VulkanSDK");
+                if (Directory.Exists(path))
                 {
-                    path = Path.Combine(subDirs[0], "macOS");
-                    if (Directory.Exists(path))
-                        vulkanSdk = path;
+                    var subDirs = Directory.GetDirectories(path);
+                    if (subDirs.Length != 0)
+                    {
+                        path = Path.Combine(subDirs[0], "macOS");
+                        if (Directory.Exists(path))
+                            vulkanSdk = path;
+                    }
                 }
             }
+            else if (platform == TargetPlatform.Linux)
+            {
+                // Try to use system-installed Vulkan SDK
+                if (File.Exists("/usr/include/vulkan/vulkan.h"))
+                    vulkanSdk = "/usr/include";
+            }
         }
         if (vulkanSdk != null)
         {
@@ -87,13 +96,20 @@ public sealed class VulkanSdk : Sdk
         {
             var vulkanSdk = RootPath;
 
+            // Use system-installed headers
+            if (vulkanSdk.EndsWith("/include") && Directory.Exists(vulkanSdk))
+            {
+                includesFolderPath = vulkanSdk;
+                return true;
+            }
+
+            // Check potential location with headers
             var includes = new[]
             {
                 Path.Combine(vulkanSdk, "include"),
                 Path.Combine(vulkanSdk, "Include"),
                 Path.Combine(vulkanSdk, "x86_64", "include"),
             };
-
             foreach (var include in includes)
             {
                 if (Directory.Exists(include))