From 3a1c4ebff8c25162c6b076d07b47997db7fc313b Mon Sep 17 00:00:00 2001
From: Joe Ardent <code@ardent.nebcorp.com>
Date: Wed, 26 Jan 2022 16:53:37 -0800
Subject: [PATCH] Handle pitching the camera with controller.

---
 src/camera.rs | 14 +++++++++++++-
 src/input.rs  |  6 ++++--
 2 files changed, 17 insertions(+), 3 deletions(-)

diff --git a/src/camera.rs b/src/camera.rs
index 35b7303..c084d87 100644
--- a/src/camera.rs
+++ b/src/camera.rs
@@ -1,9 +1,15 @@
 use bevy::prelude::*;
 
-use crate::geometry::{CyberBike, SPAWN_ALTITUDE};
+use crate::{
+    geometry::{CyberBike, SPAWN_ALTITUDE},
+    input::InputState,
+};
 
 pub(crate) const CAM_DIST: f32 = 15.0;
 
+// 85 degrees in radians
+const MAX_PITCH: f32 = 1.48353;
+
 #[derive(Component, Debug)]
 pub struct CyberCam;
 
@@ -20,6 +26,7 @@ fn setup_cybercam(mut commands: Commands) {
 fn follow_cyberbike(
     bike_query: Query<&Transform, (Without<CyberCam>, With<CyberBike>)>,
     mut cam_query: Query<&mut Transform, (With<CyberCam>, Without<CyberBike>)>,
+    input: Res<InputState>,
 ) {
     let bike_xform = bike_query.single();
     let up = bike_xform.translation.normalize();
@@ -30,6 +37,11 @@ fn follow_cyberbike(
     let mut cam_xform = cam_query.single_mut();
     cam_xform.translation = cam_pos;
     cam_xform.look_at(look_at, up);
+
+    // handle input pitch
+    let angle = input.pitch.powi(3) * MAX_PITCH;
+    let axis = cam_xform.right();
+    cam_xform.rotate(Quat::from_axis_angle(axis, angle));
 }
 
 pub struct CyberCamPlugin;
diff --git a/src/input.rs b/src/input.rs
index 4010952..3d4ad18 100644
--- a/src/input.rs
+++ b/src/input.rs
@@ -9,7 +9,7 @@ pub(crate) struct InputState {
     pub yaw: f32,
     pub throttle: f32,
     pub brake: bool,
-    pub _pitch: f32,
+    pub pitch: f32,
 }
 
 fn update_input(events: Res<Events<GamepadEvent>>, mut istate: ResMut<InputState>) {
@@ -32,7 +32,9 @@ fn update_input(events: Res<Events<GamepadEvent>>, mut istate: ResMut<InputState
                 istate.yaw = -val;
             }
             // ignore spurious vertical movement for now
-            GamepadEventType::AxisChanged(GamepadAxisType::LeftStickY, _) => {}
+            GamepadEventType::AxisChanged(GamepadAxisType::LeftStickY, val) => {
+                istate.pitch = val;
+            }
             _ => {
                 info!("unhandled gamepad event: {:?}", ev);
             }