Added the delta-tooling

crates/resolved-cli/src/main.rs

@@ -75,6 +75,10 @@ struct RenderArgs {
     /// give the same image.
     #[arg(long, default_value_t = 0)]
     frame: u64,
+    /// From camera C1: leave out the detector's noise, dark current and fixed pattern
+    /// (saturation and blooming stay), so renders differ only where their light does.
+    #[arg(long)]
+    noiseless: bool,
     /// From camera C2: how far in pixels the PSF must reach from a point (default 16).
     /// The FFT grid grows to hold it, and the PSF then reaches as far as the grid
     /// allows: 64 px at 1920 x 1080 and 2 x 2 supersampling, up to 1088 px at 1 x 1.
@@ -169,7 +173,10 @@ fn render(args: &RenderArgs) -> Result<(), String> {
     let path = args.scene.as_path();
     let file = SceneFile::read(path)?;
     let dir = path.parent().unwrap_or(Path::new("."));
-    let camera = file.camera(dir)?;
+    let mut camera = file.camera(dir)?;
+    if args.noiseless {
+        camera.detector = camera.detector.noiseless();
+    }
 
     // What the tiers need, gathered before the renderer exists so it can check them.
     let start = Instant::now();

crates/resolved-cli/tests/cli.rs

@@ -120,6 +120,41 @@ fn example_scene_on_gpu_and_cpu() {
     );
 }
 
+#[test]
+fn noiseless_renders_do_not_depend_on_the_seed() {
+    let render = |seed: &str, noiseless: bool| {
+        let out = out_dir().join(format!("noiseless-{seed}-{noiseless}.png"));
+        let mut args = vec![
+            "render",
+            "--scene",
+            "examples/scenes/boxwing.toml",
+            "--adapter",
+            "gpu",
+            "--camera",
+            "C1",
+            "--seed",
+            seed,
+            "--out",
+            out.to_str().unwrap(),
+        ];
+        if noiseless {
+            args.push("--noiseless");
+        }
+        let result = resolved(&args);
+        assert!(
+            result.status.success(),
+            "{}",
+            String::from_utf8_lossy(&result.stderr)
+        );
+        image::open(&out).unwrap().into_rgb16()
+    };
+    assert_ne!(render("1", false), render("2", false));
+    let quiet = render("1", true);
+    assert_eq!(quiet, render("2", true));
+    // Empty space reads exactly the bias, with no dark current or read noise.
+    assert_eq!(quiet.get_pixel(0, 0).0, [64 << 4; 3]);
+}
+
 #[test]
 fn pretty_previews_lift_the_darks_and_leave_space_black() {
     let preview = |pretty: bool| {