From 4512b6368169b184e3b000facd959a0ab7d863de Mon Sep 17 00:00:00 2001
From: hut <hut@hut.pm>
Date: Fri, 5 Apr 2024 19:34:01 +0200
Subject: [PATCH] generalize with generics

---
 src/camera.rs | 46 ++++++++++++++++++++++------------------------
 src/hud.rs    |  9 ++++++---
 2 files changed, 28 insertions(+), 27 deletions(-)

diff --git a/src/camera.rs b/src/camera.rs
index 31da49f..414833e 100644
--- a/src/camera.rs
+++ b/src/camera.rs
@@ -336,33 +336,31 @@ fn apply_input_to_player(
 }
 
 // Find the closest world object that the player is looking at
-pub fn find_closest_target(
-    q_objects: Query<(Entity, &Transform), (With<hud::IsClickable>, Without<hud::IsTargeted>)>,
-    q_camera: Query<&Transform, With<Camera>>,
-) -> (Option<Entity>, f32)
+pub fn find_closest_target<TargetSpecifier>(
+    objects: Vec<(TargetSpecifier, &Transform)>,
+    camera_transform: &Transform,
+) -> (Option<TargetSpecifier>, f32)
 {
-    let mut closest_entity: Option<Entity> = None;
+    let mut closest_entity: Option<TargetSpecifier> = None;
     let mut closest_distance: f32 = f32::MAX;
-    if let Ok(camtrans) = q_camera.get_single() {
-        let target_vector = (camtrans.rotation * Vec3::new(0.0, 0.0, -1.0))
+    let target_vector = (camera_transform.rotation * Vec3::new(0.0, 0.0, -1.0))
+        .normalize_or_zero();
+    let field_of_view = 20.0f32.to_radians();
+    let max_angle = field_of_view / 2.0;
+    for (entity, trans) in objects {
+        // Use Transform instead of Position because we're basing this
+        // not on the player mesh but on the camera, which doesn't have a position.
+        let pos_vector = (trans.translation - camera_transform.translation)
             .normalize_or_zero();
-        let field_of_view = 20.0f32.to_radians();
-        let max_angle = field_of_view / 2.0;
-        for (entity, trans) in &q_objects {
-            // Use Transform instead of Position because we're basing this
-            // not on the player mesh but on the camera, which doesn't have a position.
-            let pos_vector = (trans.translation - camtrans.translation)
-                .normalize_or_zero();
-            let cosine_of_angle = target_vector.dot(pos_vector);
-            let angle = cosine_of_angle.acos();
-            if angle <= max_angle {
-                // It's in the field of view!
-                //commands.entity(entity).insert(IsTargeted);
-                let distance = trans.translation.distance(camtrans.translation);
-                if distance < closest_distance {
-                    closest_distance = distance;
-                    closest_entity = Some(entity);
-                }
+        let cosine_of_angle = target_vector.dot(pos_vector);
+        let angle = cosine_of_angle.acos();
+        if angle <= max_angle {
+            // It's in the field of view!
+            //commands.entity(entity).insert(IsTargeted);
+            let distance = trans.translation.distance(camera_transform.translation);
+            if distance < closest_distance {
+                closest_distance = distance;
+                closest_entity = Some(entity);
             }
         }
     }
diff --git a/src/hud.rs b/src/hud.rs
index e25b36a..299c179 100644
--- a/src/hud.rs
+++ b/src/hud.rs
@@ -489,7 +489,7 @@ fn update(
 
                 // Target display
                 let target: Option<DVec3>;
-                if let Ok((targetpos, actr)) = q_target.get_single() {
+                if let Ok((targetpos, _actr)) = q_target.get_single() {
                     target = Some(targetpos.0);
                 }
                 else if q_target.is_empty() {
@@ -600,8 +600,11 @@ fn handle_input(
     if mouse_input.just_pressed(settings.key_selectobject) {
         //ew_sfx.send(audio::PlaySfxEvent(audio::Sfx::Switch));
         if q_target.is_empty() {
-            if let (Some(entity), _dist) = camera::find_closest_target(q_objects, q_camera) {
-                commands.entity(entity).insert(IsTargeted);
+            if let Ok(camtrans) = q_camera.get_single() {
+                let objects: Vec<(Entity, &Transform)> = q_objects.iter().collect();
+                if let (Some(entity), _dist) = camera::find_closest_target::<Entity>(objects, camtrans) {
+                    commands.entity(entity).insert(IsTargeted);
+                }
             }
         }
         else {