🎉 Add experimental fixed-stroke-length mode

docs/changelog.md

@@ -27,6 +27,7 @@ This changelog follows the rules of [Keep a Changelog](http://keepachangelog.com
 - **Support for base64 icons:** This allows you to directly embed base64 encoded images. This will be especially helpful for menus which are dynamically generated via some sort of API in the future. Use `"base64"` as the icon theme and provide the base64 encoded image as the `"icon"`. This will be a string starting with something like `"data:image/svg+xml;base64, ..."`. This even supports animated gifs!
 - **Version information in the sidebar:** The sidebar now shows some version information in the development tab. This includes the version of Kando, the version of Electron, and the currently used backend.
 - An option to the menu editor which **allows warping the mouse pointer to the center of the menu** when the menu is opened in centered mode. This allows to directly engage in turbo mode even if the menu is shown at the center of the screen.
+- **An experimental Fixed-Stroke-Length Mode:** If you set `"menuOptions": {"fixedStrokeLength": <number of pixels>}` to a value greater than 0, Marking Mode and Turbo will be disabled. Instead, submenus will be opened when the mouse is moved the given distance from the center of the menu. 
 - **Adjustable fade-in and fade-out duration of the menu:** For now, it is only possible to change this via the `"menuOptions": {"fadeInDuration": 150}` and `"menuOptions": {"fadeOutDuration": 250}` properties in the `config.json` file. In the future, this will be exposed in the settings UI.
 - **Possibility to hide sidebar and editor buttons:** You can now add
   ```json

docs/config-files.md

@@ -54,6 +54,7 @@ Property | Default Value | Description
 `gestureMinStrokeAngle` | `20` | Smaller turns will not lead to selections (in degrees).
 `gestureJitterThreshold` | `10` | Smaller pointer movements will not be considered at all during gesture recognition (in pixels).
 `gesturePauseTimeout` | `100` | If the pointer is stationary for this many milliseconds, the current item will be selected during gesture recognition.
+`fixedStrokeLength` | `0` | If set to a value greater than 0, items will be instantly selected if the mouse travelled more than `centerDeadZone` + `fixedStrokeLength` pixels in marking or turbo mode. Any other gesture detection based on angles or motion speed will be disabled in this case.
 `rmbSelectsParent` | `false` | If enabled, the parent of a selected item will be selected on a right mouse button click. Else the menu will be closed directly.
 
 ### The `editorOptions` Property

src/main/app.ts

@@ -134,6 +134,7 @@ export class KandoApp {
           gestureMinStrokeAngle: 20,
           gestureJitterThreshold: 10,
           gesturePauseTimeout: 100,
+          fixedStrokeLength: 0,
           rmbSelectsParent: false,
         },
         editorOptions: {

src/renderer/menu/input-methods/gesture-detector.ts

@@ -52,6 +52,20 @@ export class GestureDetector extends EventEmitter {
    */
   public pauseTimeout = 100;
 
+  /**
+   * This is used if fixedStrokeLength is greater than zero to allow for distance-based
+   * selections.
+   */
+  public centerDeadZone = 50;
+
+  /**
+   * If set to a value greater than 0, items will be instantly selected if the mouse
+   * travelled more than centerDeadZone + fixedStrokeLength pixels in marking or turbo
+   * mode. Any other gesture detection based on angles or motion speed will be disabled in
+   * this case.
+   */
+  public fixedStrokeLength = 0;
+
   /**
    * This method detects the gestures. It should be called if the mouse pointer was moved
    * while the left mouse button is held down. Consider the diagram below:
@@ -85,6 +99,22 @@ export class GestureDetector extends EventEmitter {
 
       const strokeLength = math.getLength(strokeDir);
 
+      // If fixedStrokeLength is set, we only need to check if the stroke is long enough.
+      if (this.fixedStrokeLength > 0) {
+        const minStrokeLength = this.fixedStrokeLength + this.centerDeadZone;
+        if (strokeLength > minStrokeLength) {
+          const idealCoords = {
+            x: this.strokeStart.x + (strokeDir.x / strokeLength) * minStrokeLength,
+            y: this.strokeStart.y + (strokeDir.y / strokeLength) * minStrokeLength,
+          };
+
+          this.reset(idealCoords);
+          this.emit('selection', idealCoords);
+        }
+        this.strokeEnd = coords;
+        return;
+      }
+
       if (strokeLength > this.minStrokeLength) {
         // Calculate the vector E->M in the diagram above.
         const tipDir = { x: coords.x - this.strokeEnd.x, y: coords.y - this.strokeEnd.y };

src/renderer/menu/menu.ts

@@ -68,6 +68,14 @@ export class MenuOptions {
    */
   gesturePauseTimeout = 100;
 
+  /**
+   * If set to a value greater than 0, items will be instantly selected if the mouse
+   * travelled more than centerDeadZone + fixedStrokeLength pixels in marking or turbo
+   * mode. Any other gesture detection based on angles or motion speed will be disabled in
+   * this case.
+   */
+  fixedStrokeLength = 0;
+
   /**
    * If enabled, the parent of a selected item will be selected on a right mouse button
    * click. Else the menu will be closed directly.
@@ -392,6 +400,8 @@ export class Menu extends EventEmitter {
     this.pointerInput.gestureDetector.jitterThreshold =
       this.options.gestureJitterThreshold;
     this.pointerInput.gestureDetector.pauseTimeout = this.options.gesturePauseTimeout;
+    this.pointerInput.gestureDetector.fixedStrokeLength = this.options.fixedStrokeLength;
+    this.pointerInput.gestureDetector.centerDeadZone = this.options.centerDeadZone;
   }
 
   // --------------------------------------------------------------------- private methods