From edb38589b1fe8b806d28264393ee172d03b6c75c Mon Sep 17 00:00:00 2001
From: Steven Le Rouzic <steven.lerouzic@gmail.com>
Date: Tue, 21 Jan 2025 21:49:20 +0100
Subject: Add vulkan_loader

---
 game/BUILD.bazel               |  2 +-
 game/main.cpp                  | 19 +++++++++++++++----
 hk21/vulkan_loader/BUILD.bazel | 15 +++++++++++++++
 hk21/vulkan_loader/api.hpp     | 23 +++++++++++++++++++++++
 hk21/vulkan_loader/fns.hpp     |  3 +++
 hk21/vulkan_loader/loader.cpp  | 25 +++++++++++++++++++++++++
 6 files changed, 82 insertions(+), 5 deletions(-)
 create mode 100644 hk21/vulkan_loader/BUILD.bazel
 create mode 100644 hk21/vulkan_loader/api.hpp
 create mode 100644 hk21/vulkan_loader/fns.hpp
 create mode 100644 hk21/vulkan_loader/loader.cpp

diff --git a/game/BUILD.bazel b/game/BUILD.bazel
index 1f59b90..6a5cdfd 100644
--- a/game/BUILD.bazel
+++ b/game/BUILD.bazel
@@ -6,6 +6,6 @@ cc_binary(
     deps = [
         "@asl//asl",
         "@sdl3_windows//:sdl3",
-        "//vendor/vulkan",
+        "//hk21/vulkan_loader",
     ],
 )
diff --git a/game/main.cpp b/game/main.cpp
index c78c41e..7bbbd71 100644
--- a/game/main.cpp
+++ b/game/main.cpp
@@ -5,10 +5,7 @@
 #include <SDL3/SDL_main.h>
 #include <SDL3/SDL_vulkan.h>
 
-#define VK_NO_STDDEF_H
-#define VK_NO_STDINT_H
-#define VK_NO_PROTOTYPES
-#include <vulkan.h>
+#include "hk21/vulkan_loader/api.hpp"
 
 int SDL_main(int /* argc */, char* /* argv */[])
 {
@@ -36,6 +33,20 @@ int SDL_main(int /* argc */, char* /* argv */[])
     instance_extensions.push(VK_EXT_DEBUG_UTILS_EXTENSION_NAME);
 
     device_extensions.push(VK_KHR_SWAPCHAIN_EXTENSION_NAME);
+    
+    auto vkGetInstanceProcAddr = asl::bit_cast<PFN_vkGetInstanceProcAddr>(SDL_Vulkan_GetVkGetInstanceProcAddr());
+    auto status = vulkan_loader::load_global(vkGetInstanceProcAddr);
+    if (!status.ok())
+    {
+        asl::eprint("Couldn't load global Vulkan functions: {}\n", status);
+    }
+
+    uint32_t version{};
+    vkEnumerateInstanceVersion(&version);
+
+    asl::print("Vulkan version: {}.{}\n",
+        VK_API_VERSION_MAJOR(version), // NOLINT
+        VK_API_VERSION_MINOR(version)); // NOLINT
    
     bool running = true;
     while (running)
diff --git a/hk21/vulkan_loader/BUILD.bazel b/hk21/vulkan_loader/BUILD.bazel
new file mode 100644
index 0000000..8aa55a1
--- /dev/null
+++ b/hk21/vulkan_loader/BUILD.bazel
@@ -0,0 +1,15 @@
+cc_library(
+    name = "vulkan_loader",
+    hdrs = [
+        "api.hpp",
+    ],
+    srcs = [
+        "loader.cpp",
+        "fns.hpp",
+    ],
+    deps = [
+        "//vendor/vulkan",
+        "@asl//asl",
+    ],
+    visibility = ["//:__subpackages__"],
+)
diff --git a/hk21/vulkan_loader/api.hpp b/hk21/vulkan_loader/api.hpp
new file mode 100644
index 0000000..08003e5
--- /dev/null
+++ b/hk21/vulkan_loader/api.hpp
@@ -0,0 +1,23 @@
+#pragma once
+
+#include <asl/integers.hpp>
+#include <asl/status.hpp>
+
+#define VK_NO_STDDEF_H
+#define VK_NO_STDINT_H
+#define VK_NO_PROTOTYPES
+#include <vulkan.h>
+
+#include "hk21/vulkan_loader/fns.hpp"
+
+#define FN(NAME) extern PFN_##NAME NAME;
+VULKAN_GLOBAL_FNS
+#undef FN
+
+namespace vulkan_loader
+{
+
+asl::status load_global(PFN_vkGetInstanceProcAddr load_fn);
+
+} // namespace vulkan_loader
+
diff --git a/hk21/vulkan_loader/fns.hpp b/hk21/vulkan_loader/fns.hpp
new file mode 100644
index 0000000..5e35b39
--- /dev/null
+++ b/hk21/vulkan_loader/fns.hpp
@@ -0,0 +1,3 @@
+#define VULKAN_GLOBAL_FNS \
+    FN(vkEnumerateInstanceVersion) \
+    FN(vkCreateInstance)
diff --git a/hk21/vulkan_loader/loader.cpp b/hk21/vulkan_loader/loader.cpp
new file mode 100644
index 0000000..4437282
--- /dev/null
+++ b/hk21/vulkan_loader/loader.cpp
@@ -0,0 +1,25 @@
+#include "hk21/vulkan_loader/api.hpp"
+
+#define FN(NAME) PFN_##NAME NAME;
+VULKAN_GLOBAL_FNS
+#undef FN
+
+asl::status vulkan_loader::load_global(PFN_vkGetInstanceProcAddr load_fn)
+{
+    (void)load_fn;
+    
+    bool has_errors = false;
+    
+#define FN(NAME) \
+    NAME = asl::bit_cast<PFN_##NAME>(load_fn(VK_NULL_HANDLE, #NAME)); \
+    if (NAME == nullptr) \
+    { \
+        ASL_ASSERT(NAME != nullptr); \
+        has_errors = true; \
+    }
+VULKAN_GLOBAL_FNS
+#undef FN
+
+    return has_errors ? asl::runtime_error() : asl::ok();
+}
+
-- 
cgit