implement moving with AWSD in map. this allows changing target!

src/camera.rs

@@ -44,6 +44,8 @@ pub struct MapCam {
     pub target_zoom_level: f32,
     pub pitch: f32,
     pub yaw: f32,
+    pub offset_x: f64,
+    pub offset_z: f64,
 }
 impl Default for MapCam {
     fn default() -> Self {
@@ -53,6 +55,8 @@ impl Default for MapCam {
             target_zoom_level: 10.0,
             pitch: PI * 0.3,
             yaw: 0.0,
+            offset_x: 0.0,
+            offset_z: 0.0,
         }
     }
 }
@@ -125,6 +129,7 @@ pub fn update_map_camera(
     mut q_camera: Query<&mut Transform, (With<Camera>, Without<actor::PlayerCamera>)>,
     q_playercam: Query<&Transform, (With<actor::PlayerCamera>, Without<Camera>)>,
     q_target: Query<&Transform, (With<hud::IsTargeted>, Without<Camera>, Without<actor::PlayerCamera>)>,
+    q_target_changed: Query<(), Changed<hud::IsTargeted>>,
     mut mouse_events: EventReader<MouseMotion>,
     mut er_mousewheel: EventReader<MouseWheel>,
     keyboard_input: Res<ButtonInput<KeyCode>>,
@@ -149,9 +154,37 @@ pub fn update_map_camera(
     // direction parameter for the Transform.look_at function is ambiguous
     // at the extreme values and the orientation will flicker back/forth.
     let epsilon = 0.001;
+    let min_zoom = target.scale.x * 2.0;
+    let max_zoom = 17e18; // at this point, camera starts glitching
     mapcam.pitch = (mapcam.pitch + mouse_delta.y / 180.0 * settings.mouse_sensitivity).clamp(-PI / 2.0 + epsilon, PI / 2.0 - epsilon);
     mapcam.yaw += mouse_delta.x / 180.0 * settings.mouse_sensitivity;
 
+    // Reset movement offset if target changes
+    if !q_target_changed.is_empty() {
+        mapcam.offset_x = 0.0;
+        mapcam.offset_z = 0.0;
+    }
+
+    // Get keyboard movement
+    let mut offset_x = 0.0;
+    let mut offset_z = 0.0;
+    if keyboard_input.pressed(settings.key_forward) {
+        offset_x -= 1.0;
+    }
+    if keyboard_input.pressed(settings.key_back) {
+        offset_x += 1.0;
+    }
+    if keyboard_input.pressed(settings.key_right) {
+        offset_z -= 1.0;
+    }
+    if keyboard_input.pressed(settings.key_left) {
+        offset_z += 1.0;
+    }
+
+    // Update movement offset
+    mapcam.offset_x += (0.01 * offset_x * mapcam.zoom_level) as f64;
+    mapcam.offset_z += (0.01 * offset_z * mapcam.zoom_level) as f64;
+
     // Update zoom level
     if !mapcam.initialized {
         let factor = if target == player_transform { 7.0 } else { 1.0 };
@@ -169,17 +202,18 @@ pub fn update_map_camera(
     for wheel_event in er_mousewheel.read() {
         change_zoom -= wheel_event.y * 3.0;
     }
-    mapcam.target_zoom_level = (mapcam.target_zoom_level * 1.1f32.powf(change_zoom)).clamp(target.scale.x, 17e18);
+    mapcam.target_zoom_level = (mapcam.target_zoom_level * 1.1f32.powf(change_zoom)).clamp(min_zoom, max_zoom);
     let zoom_speed = 0.05; // should be between 0.0001 (slow) and 1.0 (instant)
-    mapcam.zoom_level = zoom_speed * mapcam.target_zoom_level + (1.0 - zoom_speed) * mapcam.zoom_level;
+    mapcam.zoom_level = (zoom_speed * mapcam.target_zoom_level + (1.0 - zoom_speed) * mapcam.zoom_level).clamp(min_zoom, max_zoom);
 
     // Update point of view
-    let pov_rotation = Quat::from_euler(EulerRot::XYZ, 0.0, mapcam.yaw, mapcam.pitch);
+    let pov_rotation = DQuat::from_euler(EulerRot::XYZ, 0.0, mapcam.yaw as f64, mapcam.pitch as f64);
-    let point_of_view = pov_rotation * (mapcam.zoom_level * Vec3::new(1.0, 0.0, 0.0));
+    let offset = DVec3::new(mapcam.offset_x, 0.0, mapcam.offset_z);
+    let point_of_view = offset + pov_rotation * (mapcam.zoom_level as f64 * DVec3::new(1.0, 0.0, 0.0));
 
     // Apply updates to camera
-    camera_transform.translation = target.translation + point_of_view;
+    camera_transform.translation = target.translation + point_of_view.as_vec3();
-    camera_transform.look_at(target.translation, Vec3::Y);
+    camera_transform.look_at(target.translation + offset.as_vec3(), Vec3::Y);
 }
 
 pub fn update_fov(