From e653d7663581d48c4a2d088196ceb6bf38893e1f Mon Sep 17 00:00:00 2001
From: Richard Ward <johndoe6345789@gmail.com>
Date: Thu, 18 Dec 2025 19:45:45 +0000
Subject: [PATCH] build scripts

---
 .gitignore                           |  1 +
 CMakeLists.txt                       |  6 +++
 README.md                            | 10 ++++
 scripts/setup_vendor_dependencies.py | 72 ++++++++++++++++++++++++++++
 4 files changed, 89 insertions(+)
 create mode 100644 scripts/setup_vendor_dependencies.py

diff --git a/.gitignore b/.gitignore
index a75d751..98586b8 100644
--- a/.gitignore
+++ b/.gitignore
@@ -43,3 +43,4 @@
 .venv/
 venv/
 env/
+vendor/
diff --git a/CMakeLists.txt b/CMakeLists.txt
index 7b21d16..148d750 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -2,6 +2,12 @@ cmake_minimum_required(VERSION 3.24)
 project(SDL3App LANGUAGES CXX)
 option(BUILD_SDL3_APP "Build the SDL3 Vulkan demo" ON)
 
+set(VENDOR_INSTALL_DIR "${CMAKE_SOURCE_DIR}/vendor/install")
+if(EXISTS "${VENDOR_INSTALL_DIR}")
+    list(APPEND CMAKE_PREFIX_PATH "${VENDOR_INSTALL_DIR}")
+    message(STATUS "Using vendored dependencies from ${VENDOR_INSTALL_DIR}")
+endif()
+
 set(CMAKE_CXX_STANDARD 23)
 set(CMAKE_CXX_STANDARD_REQUIRED ON)
 set(CMAKE_CXX_EXTENSIONS OFF)
diff --git a/README.md b/README.md
index edc4b3d..13b074d 100644
--- a/README.md
+++ b/README.md
@@ -18,6 +18,16 @@ A minimal SDL3 + Vulkan spinning cube demo.
    cmake --build build
    ```
 
+### Vendor SDL3/Vulkan from source
+
+If you cannot install the SDL3/Vulkan headers via the distro packages, run the helper to download and build them into `vendor/install`:
+
+```
+python3 scripts/setup_vendor_dependencies.py
+cmake -S . -B build -DBUILD_SDL3_APP=ON -DCMAKE_BUILD_TYPE=Release
+cmake --build build
+```
+
 Shaders are copied into `build/shaders` during configuration, so the demo can load the precompiled `cube.{vert,frag}.spv`.
 
 ## Run
diff --git a/scripts/setup_vendor_dependencies.py b/scripts/setup_vendor_dependencies.py
new file mode 100644
index 0000000..f2f761e
--- /dev/null
+++ b/scripts/setup_vendor_dependencies.py
@@ -0,0 +1,72 @@
+#!/usr/bin/env python3
+import subprocess
+import sys
+from pathlib import Path
+
+ROOT = Path(__file__).resolve().parent.parent
+VENDOR_DIR = ROOT / "vendor"
+INSTALL_DIR = VENDOR_DIR / "install"
+
+
+def run(command, cwd=None):
+    print(f"[vendor-deps] running: {' '.join(command)} (cwd={cwd or ROOT})")
+    subprocess.run(command, cwd=cwd or ROOT, check=True)
+
+
+def fetch_repo(name, url, ref):
+    target = VENDOR_DIR / name
+    if (target / ".git").exists():
+        print(f"[vendor-deps] updating {name}")
+        run(["git", "-C", str(target), "fetch", "--tags", "origin"])
+        run(["git", "-C", str(target), "checkout", ref])
+        run(["git", "-C", str(target), "reset", "--hard", f"origin/{ref}"])
+    else:
+        print(f"[vendor-deps] cloning {name}")
+        run(["git", "clone", "--depth", "1", "--branch", ref, url, str(target)])
+
+
+def build_and_install(source_dir, build_dir, cmake_options=None):
+    cmake_options = cmake_options or []
+    build_dir.mkdir(parents=True, exist_ok=True)
+    run(
+        [
+            "cmake",
+            "-S",
+            str(source_dir),
+            "-B",
+            str(build_dir),
+            "-DCMAKE_BUILD_TYPE=Release",
+            f"-DCMAKE_INSTALL_PREFIX={INSTALL_DIR}",
+            *cmake_options,
+        ]
+    )
+    run(["cmake", "--build", str(build_dir), "--", f"-j{max(1, (subprocess.os.cpu_count() or 1))}"])
+    run(["cmake", "--install", str(build_dir)])
+
+
+def main():
+    VENDOR_DIR.mkdir(exist_ok=True)
+    INSTALL_DIR.mkdir(exist_ok=True)
+
+    fetch_repo("SDL", "https://github.com/libsdl-org/SDL.git", "release-3.0.0")
+    build_and_install(
+        VENDOR_DIR / "SDL",
+        VENDOR_DIR / "build-sdl",
+        ["-DSDL_SHARED=OFF", "-DSDL_STATIC=ON", "-DSDL_TEST=OFF", "-DBUILD_SHARED_LIBS=OFF"],
+    )
+
+    fetch_repo("Vulkan-Loader", "https://github.com/KhronosGroup/Vulkan-Loader.git", "sdk-1.3.275")
+    build_and_install(
+        VENDOR_DIR / "Vulkan-Loader",
+        VENDOR_DIR / "build-vulkan-loader",
+        ["-DBUILD_WSI=OFF", "-DBUILD_SAMPLES=OFF"],
+    )
+
+    print(f"[vendor-deps] vendor dependencies built into {INSTALL_DIR}")
+
+
+if __name__ == "__main__":
+    try:
+        main()
+    except subprocess.CalledProcessError as exc:
+        sys.exit(exc.returncode)