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src/helpers/camera.rs

@@ -0,0 +1,52 @@
+use bevy::{input::ButtonInput, math::Vec3, prelude::*, render::camera::Camera};
+
+use crate::TileOffset;
+
+// Todo: Middle mouse button should drag the playfield around
+// Zoom with + and -
+#[allow(dead_code)]
+pub fn movement(
+    time: Res<Time>,
+    keyboard_input: Res<ButtonInput<KeyCode>>,
+    mut query: Query<(&mut Transform, &mut TileOffset, &mut OrthographicProjection), With<Camera>>,
+) {
+    for (mut transform, mut offset, mut ortho) in query.iter_mut() {
+        let mut direction = Vec3::ZERO;
+
+        if keyboard_input.pressed(KeyCode::KeyA) {
+            direction -= Vec3::new(1.0, 0.0, 0.0);
+        }
+
+        if keyboard_input.pressed(KeyCode::KeyD) {
+            direction += Vec3::new(1.0, 0.0, 0.0);
+        }
+
+        if keyboard_input.pressed(KeyCode::KeyW) {
+            direction += Vec3::new(0.0, 1.0, 0.0);
+        }
+
+        if keyboard_input.pressed(KeyCode::KeyS) {
+            direction -= Vec3::new(0.0, 1.0, 0.0);
+        }
+
+        if keyboard_input.pressed(KeyCode::KeyZ) {
+            ortho.scale += time.delta_seconds();
+        }
+
+        if keyboard_input.pressed(KeyCode::KeyX) {
+            ortho.scale -= time.delta_seconds();
+        }
+
+        ortho.scale = ortho.scale.clamp(0.5, 1.0);
+
+        let z = transform.translation.z;
+        offset.translation += time.delta_seconds() * direction * (16.0 * 8.0);
+
+        offset.x = (offset.translation.x / 16.0) as isize;
+        offset.y = (offset.translation.y / 16.0) as isize;
+
+        transform.translation = offset.translation % 16.0;
+
+        transform.translation.z = z;
+    }
+}