feat(contrib): add mouse input to flycam controls

1 files changed, 39 insertions, 0 deletions

diff --git a/stockton-types/src/components/mod.rs b/stockton-types/src/components/mod.rs
index 6f127c1..f5d12e7 100644
--- a/stockton-types/src/components/mod.rs
+++ b/stockton-types/src/components/mod.rs
@@ -15,8 +15,17 @@
  * with this program.  If not, see <http://www.gnu.org/licenses/>.
  */
 
+use na::{Mat4, Vec4};
+use std::f32::consts::PI;
+
 use crate::Vector3;
 
+/// 90 degrees in radians
+const R89: f32 = (PI / 180.0) * 89.0;
+
+/// 180 degrees in radians
+const R180: f32 = PI;
+
 #[derive(Clone, Copy, Debug, PartialEq)]
 pub struct Transform {
     /// Position of the object
@@ -26,6 +35,36 @@ pub struct Transform {
     pub rotation: Vector3,
 }
 
+impl Transform {
+    pub fn rotate(&mut self, vec: Vector3) {
+        self.rotation += vec;
+
+        // Clamp -pi/2 < pitch < pi/2
+        if self.rotation.x > R89 {
+            self.rotation.x = R89;
+        } else if self.rotation.x <= -R89 {
+            self.rotation.x = -R89;
+        }
+
+        // -pi < yaw <= pi
+        if self.rotation.y <= -R180 {
+            self.rotation.y = R180 - self.rotation.y % -R180;
+        } else if self.rotation.y > 180.0 {
+            self.rotation.y = -R180 + self.rotation.y % R180;
+        }
+    }
+
+    pub fn translate(&mut self, delta: Vector3) {
+        let rot_matrix =
+            Mat4::from_euler_angles(-self.rotation.x, self.rotation.y, self.rotation.z);
+
+        let new = rot_matrix * Vec4::new(delta.x, delta.y, delta.z, 1.0);
+        self.position.x += new.x;
+        self.position.y += new.y;
+        self.position.z += new.z;
+    }
+}
+
 #[derive(Clone, Copy, Debug, PartialEq)]
 pub struct CameraSettings {
     /// FOV (radians)