add a build.rs that calls glslang

Force-Push: yes
Change-Id: I5a565f3ad343a36ffe17436b337f524805d072f7

1 files changed, 43 insertions, 0 deletions

diff --git a/build.rs b/build.rs
new file mode 100644
index 0000000..593ef3f
--- /dev/null
+++ b/build.rs
@@ -0,0 +1,43 @@
+use std::env;
+use std::fs;
+use std::path::Path;
+use std::process::Command;
+
+fn main() {
+  match process_all() {
+    Err(error) => println!("cargo-error={}", error),
+    _ => { },
+  }
+}
+
+fn process_all () -> std::io::Result<()> {
+  let out_dir = env::var_os("OUT_DIR").unwrap();
+
+  for input in fs::read_dir("shaders")? {
+    let input_path = input?.path();
+    if !input_path.is_file() {
+      continue;
+    }
+
+    let output_path
+            = Path::new(&out_dir)
+                  .join(format!("{}.spv",
+                        input_path.file_name().unwrap().to_str().unwrap()));
+
+    if !Command::new("glslang")
+           .arg("-V")
+           .arg(&input_path)
+           .arg("-o")
+           .arg(output_path)
+           .status()?.success()
+    {
+      println!("cargo::error=Failed to compile shader {}",
+               input_path.display());
+    }
+
+    println!("cargo::rerun-if-changed={}", input_path.display());
+  }
+
+  Ok(())
+}
+