feat: define hold and intensity behaviours for shake cursor

Author: SergioRibera

docs/wiki/Configuration:-Miscellaneous.md

@@ -207,6 +207,10 @@ cursor {
     shake {
         off
         max-multiplier 2.5
+        behavior "hold"
+        cooldown-ms 400
+        stopped-threshold-ms 50
+        shake-relax-ms 150
         post-expand-delay-ms 250
         expand-duration-ms 200
         decay-duration-ms 300
@@ -227,6 +231,48 @@ shake {
 }
 ```
 
+#### `behavior`
+
+Selects the shake behaviour.
+  - `"hold"` (default): keep the cursor enlarged while the pointer is moving; when the pointer stops the shrink animation is scheduled.
+  - `"intensity"`: keep the cursor enlarged while shake intensity is high; start shrinking when intensity drops below `sensitivity`.
+
+```kdl
+shake {
+    behavior "hold"
+}
+```
+
+#### `cooldown-ms`
+
+After a shrink (decay) completes, ignore new shake-triggered expansions until this many milliseconds have passed. Prevents immediate re-expansions when the pointer is noisy.
+
+```kdl
+shake {
+    cooldown-ms 400
+}
+```
+
+#### `stopped-threshold-ms`
+
+Only for `behavior "hold"`. The pointer is considered "stopped" if no motion has been observed for this many milliseconds; when stopped the shrink is scheduled after `post-expand-delay-ms`.
+
+```kdl
+shake {
+    stopped-threshold-ms 50
+}
+```
+
+#### `shake-relax-ms`
+
+Only for `behavior "intensity"`. How long the shake factor must remain below `sensitivity` before decay is scheduled. Prevents transient dips from triggering shrink.
+
+```kdl
+shake {
+    shake-relax-ms 150
+}
+```
+
 #### `post-expand-delay-ms`
 
 When the cursor is enlarged, this is the additional delay (ms) after the expansion animation finishes before the shrink animation (decay) is started. Once decay begins it will not be interrupted by further pointer movement.

niri-config/src/misc.rs

@@ -24,6 +24,10 @@ pub struct ShakeConfig {
     pub shake_interval_ms: u64,
     pub min_diagonal: f64,
     pub sensitivity: f64,
+    pub cooldown_ms: Option<u64>,
+    pub behavior: Option<String>,
+    pub stopped_threshold_ms: Option<u64>,
+    pub shake_relax_ms: Option<u64>,
 }
 
 impl Default for ShakeConfig {
@@ -37,6 +41,10 @@ impl Default for ShakeConfig {
             shake_interval_ms: 400,
             min_diagonal: 100.0,
             sensitivity: 2.0,
+            cooldown_ms: Some(400),
+            behavior: Some(String::from("hold")),
+            stopped_threshold_ms: Some(50),
+            shake_relax_ms: Some(150),
         }
     }
 }
@@ -61,6 +69,14 @@ pub struct ShakeConfigPart {
     pub min_diagonal: Option<f64>,
     #[knuffel(child, unwrap(argument))]
     pub sensitivity: Option<f64>,
+    #[knuffel(child, unwrap(argument))]
+    pub cooldown_ms: Option<u64>,
+    #[knuffel(child, unwrap(argument, str))]
+    pub behavior: Option<String>,
+    #[knuffel(child, unwrap(argument))]
+    pub stopped_threshold_ms: Option<u64>,
+    #[knuffel(child, unwrap(argument))]
+    pub shake_relax_ms: Option<u64>,
 }
 
 impl MergeWith<ShakeConfigPart> for ShakeConfig {
@@ -76,6 +92,10 @@ impl MergeWith<ShakeConfigPart> for ShakeConfig {
         merge_clone!((self, part), decay_duration_ms);
         merge_clone!((self, part), shake_interval_ms);
         merge_clone!((self, part), min_diagonal);
+        merge_clone_opt!((self, part), cooldown_ms);
+        merge_clone_opt!((self, part), behavior);
+        merge_clone_opt!((self, part), stopped_threshold_ms);
+        merge_clone_opt!((self, part), shake_relax_ms);
     }
 }