From 172ca74f7099a0743a9a756a44f046ce9e188713 Mon Sep 17 00:00:00 2001
From: Kearwood Gilbert <kearwood@kearwood.com>
Date: Tue, 23 Jun 2020 15:08:39 -0700
Subject: [PATCH] Now using Volk rather than statically linking the Vulkan
 loader

---
 .gitmodules              |  6 ++++++
 3rdparty/volk            |  1 +
 3rdparty/vulkan          |  1 +
 CMakeLists.txt           | 44 +++++++++++++++++++++++++++++++++++++---
 kraken/KRContext.cpp     | 10 ++++++++-
 kraken/KREngine-common.h |  1 +
 6 files changed, 59 insertions(+), 4 deletions(-)
 create mode 160000 3rdparty/volk
 create mode 160000 3rdparty/vulkan

diff --git a/.gitmodules b/.gitmodules
index db4ce41..acb441e 100644
--- a/.gitmodules
+++ b/.gitmodules
@@ -10,3 +10,9 @@
 [submodule "3rdparty/glslang"]
 	path = 3rdparty/glslang
 	url = git@github.com:KhronosGroup/glslang.git
+[submodule "3rdparty/vulkan"]
+	path = 3rdparty/vulkan
+	url = https://github.com/KhronosGroup/Vulkan-Headers
+[submodule "3rdparty/volk"]
+	path = 3rdparty/volk
+	url = https://github.com/zeux/volk
diff --git a/3rdparty/volk b/3rdparty/volk
new file mode 160000
index 0000000..5d2e2cf
--- /dev/null
+++ b/3rdparty/volk
@@ -0,0 +1 @@
+Subproject commit 5d2e2cf91f8a1fe4156d4c6b5c814d45d733684a
diff --git a/3rdparty/vulkan b/3rdparty/vulkan
new file mode 160000
index 0000000..8188e3f
--- /dev/null
+++ b/3rdparty/vulkan
@@ -0,0 +1 @@
+Subproject commit 8188e3fbbc105591064093440f88081fb957d4f0
diff --git a/CMakeLists.txt b/CMakeLists.txt
index f559ef3..1484573 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -109,11 +109,49 @@ include_directories(hydra/include)
 list (APPEND EXTRA_LIBS hydra)
 
 # ---- Vulkan ----
-if(NOT ANDROID)
-find_package(Vulkan REQUIRED)
-list (APPEND EXTRA_LIBS Vulkan::Vulkan)
+add_library(vulkan INTERFACE)
+set(VULKAN_INCLUDE_DIR ${CMAKE_CURRENT_SOURCE_DIR}/3rdparty/vulkan/include)
+target_sources(vulkan INTERFACE ${VULKAN_INCLUDE_DIR}/vulkan/vulkan.h)
+target_include_directories(vulkan INTERFACE ${VULKAN_INCLUDE_DIR})
+
+target_compile_definitions(vulkan INTERFACE VK_NO_PROTOTYPES)
+
+if(ANDROID)
+    target_compile_definitions(vulkan INTERFACE VK_USE_PLATFORM_ANDROID_KHR)
+elseif(WIN32)
+    target_compile_definitions(vulkan INTERFACE VK_USE_PLATFORM_WIN32_KHR)
+elseif(APPLE)
+    target_compile_definitions(vulkan INTERFACE VK_USE_PLATFORM_MACOS_MVK)
+elseif(UNIX)
+    # See whether X11 is available. If not, fall back to direct-to-display mode.
+    find_package(X11 QUIET)
+    if (X11_FOUND)
+        target_compile_definitions(vulkan INTERFACE VK_USE_PLATFORM_XCB_KHR)
+    else()
+        set(DIRECT_TO_DISPLAY TRUE)
+        set(DIRECT_TO_DISPLAY TRUE PARENT_SCOPE)
+        target_compile_definitions(vulkan INTERFACE VK_USE_PLATFORM_DISPLAY_KHR)
+    endif()
 endif()
 
+list (APPEND EXTRA_LIBS vulkan)
+
+# ---- Volk ----
+# volk
+set(VOLK_DIR "${CMAKE_CURRENT_SOURCE_DIR}/3rdparty/volk")
+set(VOLK_FILES
+    "${VOLK_DIR}/volk.c"
+    "${VOLK_DIR}/volk.h")
+
+add_library(volk STATIC ${VOLK_FILES})
+
+target_link_libraries(volk PUBLIC vulkan)
+
+target_include_directories(volk PUBLIC ${VOLK_DIR})
+
+set_property(TARGET volk PROPERTY FOLDER "3rdparty")
+
+list (APPEND EXTRA_LIBS volk)
 
 # ---- GLSlang ----
 if(NOT ANDROID)
diff --git a/kraken/KRContext.cpp b/kraken/KRContext.cpp
index cb0a0f6..1bde534 100755
--- a/kraken/KRContext.cpp
+++ b/kraken/KRContext.cpp
@@ -640,6 +640,12 @@ void KRContext::receivedMemoryWarning()
 void
 KRContext::createDeviceContexts()
 {
+  VkResult res = volkInitialize();
+  if (res != VK_SUCCESS) {
+    destroyDeviceContexts();
+    return;
+  }
+
   // initialize the VkApplicationInfo structure
   VkApplicationInfo app_info = {};
   app_info.sType = VK_STRUCTURE_TYPE_APPLICATION_INFO;
@@ -662,10 +668,12 @@ KRContext::createDeviceContexts()
   inst_info.enabledLayerCount = 0;
   inst_info.ppEnabledLayerNames = NULL;
 
-  VkResult res = vkCreateInstance(&inst_info, NULL, &m_vulkanInstance);
+  res = vkCreateInstance(&inst_info, NULL, &m_vulkanInstance);
   if (res != VK_SUCCESS) {
     destroyDeviceContexts();
   }
+
+  volkLoadInstance(m_vulkanInstance);
 }
 
 void
diff --git a/kraken/KREngine-common.h b/kraken/KREngine-common.h
index a811e8b..c9ce754 100755
--- a/kraken/KREngine-common.h
+++ b/kraken/KREngine-common.h
@@ -100,6 +100,7 @@ using std::unordered_multimap;
 using std::hash;
 
 #include <vulkan/vulkan.h>
+#include <volk.h>
 #if defined(ANDROID)
 #include <GLES3/gl3.h>
 #include <GLES3/gl3ext.h>