Merge pull request #1204 from hannobraun/zoom

Invert default zoom direction; add config to override that

crates/fj-app/src/config.rs

@@ -11,6 +11,7 @@ use serde::Deserialize;
 pub struct Config {
     pub default_path: Option<PathBuf>,
     pub default_model: Option<PathBuf>,
+    pub invert_zoom: Option<bool>,
 }
 
 impl Config {

crates/fj-app/src/main.rs

@@ -80,11 +80,13 @@ fn main() -> anyhow::Result<()> {
         return Ok(());
     }
 
+    let invert_zoom = config.invert_zoom.unwrap_or(false);
+
     if let Some(model) = model {
         let watcher = model.load_and_watch(parameters)?;
-        run(Some(watcher), shape_processor, status)?;
+        run(Some(watcher), shape_processor, status, invert_zoom)?;
     } else {
-        run(None, shape_processor, status)?;
+        run(None, shape_processor, status, invert_zoom)?;
     }
 
     Ok(())

crates/fj-viewer/src/input/zoom.rs

@@ -14,6 +14,6 @@ impl Zoom {
         let distance = (focus_point.0 - camera.position()).magnitude();
         let displacement = zoom_delta * distance.into_f64();
         camera.translation = camera.translation
-            * Transform::translation(Vector::from([0.0, 0.0, -displacement]));
+            * Transform::translation(Vector::from([0.0, 0.0, displacement]));
     }
 }

crates/fj-window/src/run.rs

@@ -32,6 +32,7 @@ pub fn run(
     watcher: Option<Watcher>,
     shape_processor: ShapeProcessor,
     mut status: StatusReport,
+    invert_zoom: bool,
 ) -> Result<(), Error> {
     let event_loop = EventLoop::new();
     let window = Window::new(&event_loop)?;
@@ -214,6 +215,7 @@ pub fn run(
             &window,
             &held_mouse_button,
             &mut previous_cursor,
+            invert_zoom,
         );
         if let (Some(input_event), Some(fp)) = (input_event, focus_point) {
             input_handler.handle_event(input_event, fp, &mut camera);
@@ -226,6 +228,7 @@ fn input_event(
     window: &Window,
     held_mouse_button: &Option<MouseButton>,
     previous_cursor: &mut Option<NormalizedPosition>,
+    invert_zoom: bool,
 ) -> Option<input::Event> {
     match event {
         Event::WindowEvent {
@@ -264,12 +267,20 @@ fn input_event(
         Event::WindowEvent {
             event: WindowEvent::MouseWheel { delta, .. },
             ..
-        } => Some(input::Event::Zoom(match delta {
-            MouseScrollDelta::LineDelta(_, y) => (*y as f64) * ZOOM_FACTOR_LINE,
-            MouseScrollDelta::PixelDelta(PhysicalPosition { y, .. }) => {
-                y * ZOOM_FACTOR_PIXEL
-            }
-        })),
+        } => {
+            let delta = match delta {
+                MouseScrollDelta::LineDelta(_, y) => {
+                    (*y as f64) * ZOOM_FACTOR_LINE
+                }
+                MouseScrollDelta::PixelDelta(PhysicalPosition {
+                    y, ..
+                }) => y * ZOOM_FACTOR_PIXEL,
+            };
+
+            let delta = if invert_zoom { -delta } else { delta };
+
+            Some(input::Event::Zoom(delta))
+        }
         _ => None,
     }
 }

fj.toml

@@ -5,3 +5,7 @@ default_path = "models"
 # The default models that is loaded, if none is specified. If this is a relative
 # path, it should be relative to `default_path`.
 default_model = "test"
+
+# Indicate whether to invert the zoom direction. Can be used to override the
+# OS-level setting.
+invert_zoom = false