Reworked renderer for Directives

Added OwnedTextArea & reworked textarea creation
Added ScrollBox

crates/render/src/gpustate.rs

@@ -1,13 +1,13 @@
 use anyhow::Result;
 use bytemuck;
 use galactica_content::Content;
-use galactica_system::data::ShipState;
+use galactica_system::{data::ShipState, phys::PhysSimShipHandle, PlayerDirective};
 use galactica_util::to_radians;
 use glyphon::{FontSystem, Resolution, SwashCache, TextAtlas, TextRenderer};
-use nalgebra::{Point2, Point3};
+use nalgebra::{Point2, Point3, Vector2};
 use std::{cell::RefCell, iter, rc::Rc, sync::Arc};
 use wgpu;
-use winit;
+use winit::{self};
 
 use crate::{
 	globaluniform::{GlobalDataContent, GlobalUniform, ObjectData},
@@ -17,7 +17,7 @@ use crate::{
 	texturearray::TextureArray,
 	ui::UiScriptExecutor,
 	vertexbuffer::{consts::SPRITE_INDICES, types::ObjectInstance},
-	RenderInput, RenderState, VertexBuffers,
+	InputEvent, RenderInput, RenderState, VertexBuffers,
 };
 
 /// A high-level GPU wrapper. Reads game state (via RenderInput), produces pretty pictures.
@@ -259,6 +259,8 @@ impl GPUState {
 			self.config.height = new_size.height;
 			self.surface.configure(&self.device, &self.config);
 		}
+
+		// TODO: this takes a long time. fix!
 		self.starfield.update_buffer(ct, &mut self.state);
 	}
 
@@ -274,18 +276,54 @@ impl GPUState {
 		self.starfield.update_buffer(ct, &mut self.state);
 	}
 
+	/// Handle user input
+	pub fn process_input(
+		&mut self,
+		input: RenderInput,
+		event: InputEvent,
+	) -> Result<PlayerDirective> {
+		let input = Arc::new(input);
+		self.ui.process_input(&mut self.state, input, event)
+	}
+
 	/// Main render function. Draws sprites on a window.
 	pub fn render(&mut self, input: RenderInput) -> Result<(), wgpu::SurfaceError> {
 		let input = Arc::new(input);
 
+		if let Some(ship) = input.player.ship {
+			let o = input.phys_img.get_ship(&PhysSimShipHandle(ship));
+			if let Some(o) = o {
+				match o.ship.get_data().get_state() {
+					ShipState::Landing { .. }
+					| ShipState::UnLanding { .. }
+					| ShipState::Collapsing { .. }
+					| ShipState::Flying { .. } => self
+						.ui
+						.state
+						.borrow_mut()
+						.camera
+						.set_pos(*o.rigidbody.translation()),
+
+					ShipState::Landed { target } => self
+						.ui
+						.state
+						.borrow_mut()
+						.camera
+						.set_pos(Vector2::new(target.pos.x, target.pos.y)),
+
+					ShipState::Dead => {}
+				}
+			}
+		}
+
 		// Update global values
 		self.state.queue.write_buffer(
 			&self.state.global_uniform.data_buffer,
 			0,
 			bytemuck::cast_slice(&[GlobalDataContent {
-				camera_position_x: input.camera_pos.x,
-				camera_position_y: input.camera_pos.y,
-				camera_zoom: input.camera_zoom,
+				camera_position_x: self.ui.state.borrow().camera.get_pos().x,
+				camera_position_y: self.ui.state.borrow().camera.get_pos().y,
+				camera_zoom: self.ui.state.borrow().camera.get_zoom(),
 				camera_zoom_min: input.ct.config.zoom_min,
 				camera_zoom_max: input.ct.config.zoom_max,
 				window_size_w: self.state.window_size.width as f32,
@@ -338,8 +376,10 @@ impl GPUState {
 
 			// Game coordinates (relative to camera) of ne and sw corners of screen.
 			// Used to skip off-screen sprites.
-			let clip_ne = Point2::new(-self.state.window_aspect, 1.0) * input.camera_zoom;
-			let clip_sw = Point2::new(self.state.window_aspect, -1.0) * input.camera_zoom;
+			let clip_ne = Point2::new(-self.state.window_aspect, 1.0)
+				* self.ui.state.borrow().camera.get_zoom();
+			let clip_sw = Point2::new(self.state.window_aspect, -1.0)
+				* self.ui.state.borrow().camera.get_zoom();
 
 			// Order matters, it determines what is drawn on top.
 			// The order inside ships and projectiles doesn't matter,
@@ -424,7 +464,9 @@ impl GPUState {
 					},
 					(*self.ui.state)
 						.borrow_mut()
-						.get_textareas(&input, &self.state.window),
+						.get_textareas(&input, &self.state.window)
+						.iter()
+						.map(|x| x.get_textarea()),
 					&mut self.state.text_cache,
 				)
 				.unwrap();
@@ -483,8 +525,9 @@ impl GPUState {
 			// Position adjusted for parallax
 			// TODO: adjust parallax for zoom?
 			// 1.0 is z-coordinate, which is constant for ships
-			let pos: Point2<f32> =
-				(Point2::new(ship_pos.x, ship_pos.y) - input.camera_pos) / ship_pos.z;
+			let pos: Point2<f32> = (Point2::new(ship_pos.x, ship_pos.y)
+				- self.ui.state.borrow().camera.get_pos())
+				/ ship_pos.z;
 
 			// Game dimensions of this sprite post-scale.
 			// Post-scale width or height, whichever is larger.
@@ -588,7 +631,7 @@ impl GPUState {
 			// Position adjusted for parallax
 			// TODO: adjust parallax for zoom?
 			// 1.0 is z-coordinate, which is constant for projectiles
-			let pos = (proj_pos - input.camera_pos) / 1.0;
+			let pos = (proj_pos - self.ui.state.borrow().camera.get_pos()) / 1.0;
 
 			// Game dimensions of this sprite post-scale.
 			// Post-scale width or height, whichever is larger.
@@ -649,7 +692,8 @@ impl GPUState {
 
 		for o in v {
 			// Position adjusted for parallax
-			let pos: Point2<f32> = (Point2::new(o.pos.x, o.pos.y) - input.camera_pos) / o.pos.z;
+			let pos: Point2<f32> =
+				(Point2::new(o.pos.x, o.pos.y) - self.ui.state.borrow().camera.get_pos()) / o.pos.z;
 
 			// Game dimensions of this sprite post-scale.
 			// Post-scale width or height, whichever is larger.
@@ -711,7 +755,7 @@ impl GPUState {
 			// Position adjusted for parallax
 			// TODO: adjust parallax for zoom?
 			// 1.0 is z-coordinate, which is constant for projectiles
-			let adjusted_pos = (pos - input.camera_pos) / 1.0;
+			let adjusted_pos = (pos - self.ui.state.borrow().camera.get_pos()) / 1.0;
 
 			// Game dimensions of this sprite post-scale.
 			// Post-scale width or height, whichever is larger.

crates/render/src/inputevent.rs

@@ -0,0 +1,29 @@
+use winit::{dpi::PhysicalPosition, event::VirtualKeyCode};
+
+/// Input received from the user
+#[derive(Debug)]
+pub enum InputEvent {
+	/// Mouse was moved
+	MouseMove(PhysicalPosition<f32>),
+
+	/// Mouse left button was clicked.
+	/// True if pressed, false if released.
+	MouseLeftClick(bool),
+
+	/// Mouse left button was clicked.
+	/// True if pressed, false if released.
+	MouseRightClick(bool),
+
+	/// Mouse was scrolled.
+	/// Value is number of lines, positive or negative.
+	Scroll(f32),
+
+	/// A key was pressed or released
+	Keyboard {
+		/// True if pressed, false if released
+		down: bool,
+
+		/// The key that was pressed
+		key: VirtualKeyCode,
+	},
+}

crates/render/src/lib.rs

@@ -9,6 +9,7 @@
 
 mod globaluniform;
 mod gpustate;
+mod inputevent;
 mod pipeline;
 mod renderinput;
 mod renderstate;
@@ -18,7 +19,8 @@ mod texturearray;
 mod ui;
 mod vertexbuffer;
 
-pub use gpustate::GPUState;
+pub use gpustate::*;
+pub use inputevent::*;
 pub use renderinput::RenderInput;
 use renderstate::*;
 

crates/render/src/renderinput.rs

@@ -4,23 +4,16 @@ use galactica_content::{Content, System};
 use galactica_playeragent::PlayerAgent;
 use galactica_system::phys::PhysImage;
 use galactica_util::timing::Timing;
-use nalgebra::Vector2;
 
 /// Bundles parameters passed to a single call to GPUState::render
 #[derive(Debug)]
 pub struct RenderInput {
-	/// Camera position, in world units
-	pub camera_pos: Vector2<f32>,
-
 	/// Player ship data
 	pub player: Arc<PlayerAgent>,
 
 	/// The system we're currently in
 	pub current_system: Arc<System>,
 
-	/// Height of screen, in world units
-	pub camera_zoom: f32,
-
 	/// The world state to render
 	pub phys_img: Arc<PhysImage>,
 
@@ -28,9 +21,6 @@ pub struct RenderInput {
 	/// The current time, in seconds
 	pub current_time: f32,
 
-	/// The amount of time that has passed since the last frame was drawn
-	pub time_since_last_run: f32,
-
 	/// Game content
 	pub ct: Arc<Content>,
 

crates/render/src/ui/api/directive.rs

@@ -0,0 +1,28 @@
+use rhai::{plugin::*, Dynamic, Module};
+
+#[export_module]
+#[allow(non_snake_case)]
+#[allow(non_upper_case_globals)]
+pub mod player_directive_module {
+	use galactica_system::PlayerDirective;
+
+	pub const None: PlayerDirective = PlayerDirective::None;
+	pub const Land: PlayerDirective = PlayerDirective::Land;
+	pub const UnLand: PlayerDirective = PlayerDirective::UnLand;
+
+	pub fn Engine(state: bool) -> PlayerDirective {
+		PlayerDirective::Engine(state)
+	}
+
+	pub fn TurnLeft(state: bool) -> PlayerDirective {
+		PlayerDirective::TurnLeft(state)
+	}
+
+	pub fn TurnRight(state: bool) -> PlayerDirective {
+		PlayerDirective::TurnRight(state)
+	}
+
+	pub fn Guns(state: bool) -> PlayerDirective {
+		PlayerDirective::Guns(state)
+	}
+}

crates/render/src/ui/api/event.rs

@@ -38,3 +38,31 @@ impl CustomType for PlayerShipStateEvent {
 		builder.with_name("PlayerShipStateEvent");
 	}
 }
+
+#[derive(Debug, Clone)]
+pub struct KeyboardEvent {
+	pub down: bool,
+	pub key: ImmutableString,
+}
+
+impl CustomType for KeyboardEvent {
+	fn build(mut builder: TypeBuilder<Self>) {
+		builder
+			.with_name("KeyboardEvent")
+			.with_fn("is_down", |s: &mut Self| s.down)
+			.with_fn("key", |s: &mut Self| s.key.clone());
+	}
+}
+
+#[derive(Debug, Clone)]
+pub struct ScrollEvent {
+	pub val: f32,
+}
+
+impl CustomType for ScrollEvent {
+	fn build(mut builder: TypeBuilder<Self>) {
+		builder
+			.with_name("ScrollEvent")
+			.with_fn("val", |s: &mut Self| s.val);
+	}
+}

crates/render/src/ui/api/functions/mod.rs

@@ -1,11 +1,13 @@
 mod conf;
 mod radialbar;
+mod scrollbox;
 mod sprite;
 mod textbox;
 mod ui;
 
 pub use conf::build_conf_module;
 pub use radialbar::build_radialbar_module;
+pub use scrollbox::build_scrollbox_module;
 pub use sprite::build_sprite_module;
 pub use textbox::build_textbox_module;
 pub use ui::build_ui_module;

crates/render/src/ui/api/functions/radialbar.rs

@@ -3,7 +3,7 @@ use rhai::{FnNamespace, FuncRegistration, ImmutableString, Module};
 use std::{cell::RefCell, rc::Rc};
 
 use super::super::{Color, Rect};
-use crate::ui::{elements::RadialBar, UiElement, UiState};
+use crate::ui::{elements::UiRadialBar, UiElement, UiState};
 
 pub fn build_radialbar_module(state_src: Rc<RefCell<UiState>>) -> Module {
 	let mut module = Module::new();
@@ -23,11 +23,13 @@ pub fn build_radialbar_module(state_src: Rc<RefCell<UiState>>) -> Module {
 					return;
 				}
 
-				ui_state.names.push(name.clone());
-				ui_state.elements.insert(
+				ui_state.add_element(UiElement::RadialBar(UiRadialBar::new(
 					name.clone(),
-					UiElement::RadialBar(RadialBar::new(name.clone(), stroke, color, rect, 1.0)),
-				);
+					stroke,
+					color,
+					rect,
+					1.0,
+				)));
 			},
 		);
 

crates/render/src/ui/api/functions/scrollbox.rs

@@ -0,0 +1,77 @@
+use log::error;
+use rhai::{FnNamespace, FuncRegistration, ImmutableString, Module};
+use std::{cell::RefCell, rc::Rc};
+
+use super::super::Rect;
+use crate::ui::{elements::UiScrollbox, UiElement, UiState};
+
+pub fn build_scrollbox_module(state_src: Rc<RefCell<UiState>>) -> Module {
+	let mut module = Module::new();
+	module.set_id("GalacticaScrollboxModule");
+
+	let state = state_src.clone();
+	let _ = FuncRegistration::new("add")
+		.with_namespace(FnNamespace::Internal)
+		.set_into_module(&mut module, move |name: ImmutableString, rect: Rect| {
+			let mut ui_state = state.borrow_mut();
+
+			if ui_state.elements.contains_key(&name) {
+				error!("tried to make a scrollbox using an existing name `{name}`");
+				return;
+			}
+
+			ui_state.add_element(UiElement::Scrollbox(UiScrollbox::new(name.clone(), rect)));
+		});
+
+	let state = state_src.clone();
+	let _ = FuncRegistration::new("add_element")
+		.with_namespace(FnNamespace::Internal)
+		.set_into_module(
+			&mut module,
+			move |name: ImmutableString, target: ImmutableString| {
+				let mut ui_state = state.borrow_mut();
+				match ui_state.get_mut_by_name(&name) {
+					Some(UiElement::Scrollbox(_)) => {
+						match ui_state.get_mut_by_name(&target) {
+							Some(UiElement::Text(_)) | Some(UiElement::Sprite(_)) => {
+								let e = match ui_state.remove_element_incomplete(&target) {
+									Some(UiElement::Sprite(s)) => {
+										Rc::new(RefCell::new(UiElement::Sprite(s)))
+									}
+									Some(UiElement::Text(t)) => {
+										Rc::new(RefCell::new(UiElement::Text(t)))
+									}
+									_ => unreachable!(),
+								};
+
+								// Add a subelement pointing to this sprite
+								ui_state.add_element(UiElement::SubElement {
+									parent: name.clone(),
+									element: e.clone(),
+								});
+
+								// Add this sprite to a scrollbox
+								match ui_state.get_mut_by_name(&name) {
+									Some(UiElement::Scrollbox(s)) => {
+										s.add_element(e);
+									}
+									_ => unreachable!(),
+								};
+							}
+							Some(_) => {
+								error!("cannot add `{name}` to scrollbox `{name}`, invalid type.")
+							}
+							None => {
+								error!("called `scrollbox::add_element` with a non-existing target `{target}`")
+							}
+						}
+					}
+					_ => {
+						error!("called `scrollbox::add_element` on an invalid name `{name}`")
+					}
+				}
+			},
+		);
+
+	return module;
+}

crates/render/src/ui/api/functions/sprite.rs

@@ -17,12 +17,12 @@ pub fn build_sprite_module(ct_src: Arc<Content>, state_src: Rc<RefCell<UiState>>
 		.with_namespace(FnNamespace::Internal)
 		.set_into_module(
 			&mut module,
-			move |name: ImmutableString, sprite: ImmutableString, rect: Rect| {
+			move |name: ImmutableString, sprite_name: ImmutableString, rect: Rect| {
 				let mut ui_state = state.borrow_mut();
 
-				let sprite_handle = ct.sprites.get(&sprite.clone().into());
-				if sprite_handle.is_none() {
-					error!("made a sprite using an invalid source `{sprite}`");
+				let sprite = ct.sprites.get(&sprite_name.clone().into());
+				if sprite.is_none() {
+					error!("made a sprite using an invalid source `{sprite_name}`");
 					return;
 				}
 
@@ -31,15 +31,11 @@ pub fn build_sprite_module(ct_src: Arc<Content>, state_src: Rc<RefCell<UiState>>
 					return;
 				}
 
-				ui_state.names.push(name.clone());
-				ui_state.elements.insert(
+				ui_state.add_element(UiElement::Sprite(UiSprite::new(
 					name.clone(),
-					UiElement::Sprite(UiSprite::new(
-						name.clone(),
-						sprite_handle.unwrap().clone(),
+					sprite.unwrap().clone(),
 					rect,
-					)),
-				);
+				)));
 			},
 		);
 
@@ -60,8 +56,7 @@ pub fn build_sprite_module(ct_src: Arc<Content>, state_src: Rc<RefCell<UiState>>
 		.set_into_module(&mut module, move |name: ImmutableString| {
 			let mut ui_state = state.borrow_mut();
 			if ui_state.elements.contains_key(&name) {
-				ui_state.elements.remove(&name).unwrap();
-				ui_state.names.retain(|x| *x != name);
+				ui_state.remove_element(&name);
 			} else {
 				error!("called `sprite::remove` on an invalid name `{name}`")
 			}
@@ -94,7 +89,7 @@ pub fn build_sprite_module(ct_src: Arc<Content>, state_src: Rc<RefCell<UiState>>
 		);
 
 	let state = state_src.clone();
-	let _ = FuncRegistration::new("take_edge")
+	let _ = FuncRegistration::new("jump_to")
 		.with_namespace(FnNamespace::Internal)
 		.set_into_module(
 			&mut module,
@@ -110,7 +105,7 @@ pub fn build_sprite_module(ct_src: Arc<Content>, state_src: Rc<RefCell<UiState>>
 						let edge = match edge {
 							Err(_) => {
 								error!(
-								"called `sprite::take_edge` on an invalid edge `{}` on sprite `{}`",
+								"called `sprite::jump_to` on an invalid edge `{}` on sprite `{}`",
 								edge_name, sprite.index
 							);
 								return;
@@ -121,7 +116,7 @@ pub fn build_sprite_module(ct_src: Arc<Content>, state_src: Rc<RefCell<UiState>>
 						x.anim.jump_to(&edge);
 					}
 					_ => {
-						error!("called `sprite::take_edge` on an invalid name `{name}`")
+						error!("called `sprite::jump_to` on an invalid name `{name}`")
 					}
 				}
 			},

crates/render/src/ui/api/functions/textbox.rs

@@ -4,7 +4,7 @@ use rhai::{FnNamespace, FuncRegistration, ImmutableString, Module};
 use std::{cell::RefCell, rc::Rc};
 
 use super::super::{Color, Rect};
-use crate::ui::{elements::TextBox, UiElement, UiState};
+use crate::ui::{elements::UiTextBox, UiElement, UiState};
 
 pub fn build_textbox_module(
 	font_src: Rc<RefCell<FontSystem>>,
@@ -32,18 +32,14 @@ pub fn build_textbox_module(
 					return;
 				}
 
-				ui_state.names.push(name.clone());
-				ui_state.elements.insert(
-					name.clone(),
-					UiElement::Text(TextBox::new(
+				ui_state.add_element(UiElement::Text(UiTextBox::new(
 					&mut font.borrow_mut(),
 					name.clone(),
 					font_size,
 					line_height,
 					rect,
 					color,
-					)),
-				);
+				)));
 			},
 		);
 

crates/render/src/ui/api/functions/ui.rs

@@ -15,5 +15,17 @@ pub fn build_ui_module(state_src: Rc<RefCell<UiState>>) -> Module {
 			ui_state.set_scene(scene);
 		});
 
+	let state = state_src.clone();
+	let _ = FuncRegistration::new("get_camera_zoom")
+		.with_namespace(FnNamespace::Internal)
+		.set_into_module(&mut module, move || state.borrow().camera.get_zoom());
+
+	let state = state_src.clone();
+	let _ = FuncRegistration::new("set_camera_zoom")
+		.with_namespace(FnNamespace::Internal)
+		.set_into_module(&mut module, move |z: f32| {
+			state.borrow_mut().camera.set_zoom(z)
+		});
+
 	return module;
 }

crates/render/src/ui/api/helpers/rect.rs

@@ -1,9 +1,12 @@
 use nalgebra::{Point2, Vector2};
 use rhai::{CustomType, TypeBuilder};
-use winit::{dpi::LogicalSize, window::Window};
+use winit::{
+	dpi::{LogicalSize, PhysicalPosition},
+	window::Window,
+};
 
-use super::anchor::Anchor;
-use crate::{RenderInput, RenderState};
+use super::{anchor::Anchor, vector::UiVector};
+use crate::RenderState;
 
 #[derive(Debug, Clone)]
 pub struct Rect {
@@ -78,7 +81,11 @@ impl Rect {
 
 impl CustomType for Rect {
 	fn build(mut builder: TypeBuilder<Self>) {
-		builder.with_name("Rect").with_fn("Rect", Self::new);
+		builder
+			.with_name("Rect")
+			.with_fn("Rect", Self::new)
+			.with_fn("pos", |s: &mut Self| UiVector::new(s.pos.x, s.pos.y))
+			.with_fn("dim", |s: &mut Self| UiVector::new(s.dim.x, s.dim.y));
 	}
 }
 
@@ -100,17 +107,16 @@ impl CenteredRect {
 		return (pt.y < ne.y && pt.y > sw.y) && (pt.x > ne.x && pt.x < sw.x);
 	}
 
-	pub fn contains_mouse(&self, input: &RenderInput, state: &RenderState) -> bool {
+	pub fn contains_mouse(&self, state: &RenderState, mouse_pos: &PhysicalPosition<f32>) -> bool {
 		let fac = state.window.scale_factor() as f32;
 		let window_size = Vector2::new(
 			state.window_size.width as f32 / fac,
 			state.window_size.height as f32 / fac,
 		);
 
-		let pos = input.player.input.get_mouse_pos();
 		let mouse_pos = Point2::new(
-			pos.x / fac - window_size.x / 2.0,
-			window_size.y / 2.0 - pos.y / fac,
+			mouse_pos.x / fac - window_size.x / 2.0,
+			window_size.y / 2.0 - mouse_pos.y / fac,
 		);
 
 		return self.contains_point(mouse_pos);

crates/render/src/ui/api/mod.rs

@@ -1,17 +1,19 @@
+mod directive;
 mod event;
 mod functions;
 mod helpers;
 mod state;
 
+pub use directive::*;
 pub use event::*;
-use glyphon::FontSystem;
 pub use helpers::{anchor::*, color::*, rect::*, vector::*};
-use log::debug;
 pub use state::*;
 
 use super::UiState;
 use galactica_content::Content;
-use rhai::{exported_module, Dynamic, Engine};
+use galactica_system::PlayerDirective;
+use glyphon::FontSystem;
+use rhai::{exported_module, Engine};
 use std::{cell::RefCell, rc::Rc, sync::Arc};
 
 pub fn register_into_engine(
@@ -29,21 +31,27 @@ pub fn register_into_engine(
 		.build_type::<State>()
 		.build_type::<ShipState>()
 		.build_type::<SystemObjectState>()
+		.build_type::<OutfitState>()
 		// Events
 		.build_type::<MouseClickEvent>()
 		.build_type::<MouseHoverEvent>()
 		.build_type::<PlayerShipStateEvent>()
+		.build_type::<KeyboardEvent>()
+		.build_type::<ScrollEvent>()
 		// Bigger modules
 		.register_type_with_name::<Anchor>("Anchor")
-		.register_static_module("Anchor", exported_module!(anchor_mod).into());
+		.register_static_module("Anchor", exported_module!(anchor_mod).into())
+		.register_type_with_name::<PlayerDirective>("PlayerDirective")
+		.register_static_module(
+			"PlayerDirective",
+			exported_module!(player_directive_module).into(),
+		);
 
 	// Extra functions
-	engine.register_fn("print", move |d: Dynamic| {
-		debug!("{:?}", d);
-	});
-	engine.register_fn("clamp", move |x: f32, l: f32, h: f32| x.clamp(l, h));
+	engine.register_fn("clamp", |x: f32, l: f32, h: f32| x.clamp(l, h));
 
 	// Modules
+	engine.register_static_module("ui", functions::build_ui_module(state_src.clone()).into());
 	engine.register_static_module(
 		"sprite",
 		functions::build_sprite_module(ct_src.clone(), state_src.clone()).into(),
@@ -56,7 +64,10 @@ pub fn register_into_engine(
 		"radialbar",
 		functions::build_radialbar_module(state_src.clone()).into(),
 	);
-	engine.register_static_module("ui", functions::build_ui_module(state_src.clone()).into());
+	engine.register_static_module(
+		"scrollbox",
+		functions::build_scrollbox_module(state_src.clone()).into(),
+	);
 	engine.register_static_module(
 		"conf",
 		functions::build_conf_module(state_src.clone()).into(),

crates/render/src/ui/api/state.rs

@@ -1,4 +1,4 @@
-use galactica_content::{Ship, SystemObject};
+use galactica_content::{Outfit, Ship, SystemObject};
 use galactica_system::{
 	data::{self},
 	phys::{objects::PhysShip, PhysSimShipHandle},
@@ -19,14 +19,15 @@ pub struct ShipState {
 }
 
 impl ShipState {
+	// All functions passed to rhai MUST be mut,
+	// even getters.
 	fn get_content(&mut self) -> &Ship {
 		let ship = self
 			.input
 			.phys_img
 			.get_ship(self.ship.as_ref().unwrap())
 			.unwrap();
-		let handle = ship.ship.get_data().get_content();
-		handle
+		ship.ship.get_data().get_content()
 	}
 
 	fn get_ship(&mut self) -> &PhysShip {
@@ -116,28 +117,64 @@ impl CustomType for ShipState {
 	}
 }
 
+#[derive(Debug, Clone)]
+pub struct OutfitState {
+	outfit: Arc<Outfit>,
+}
+
+impl OutfitState {}
+
+impl CustomType for OutfitState {
+	fn build(mut builder: TypeBuilder<Self>) {
+		builder
+			.with_name("OutfitState")
+			.with_fn("display_name", |s: &mut Self| s.outfit.display_name.clone())
+			.with_fn("index", |s: &mut Self| s.outfit.index.to_string())
+			.with_fn("thumbnail", |s: &mut Self| {
+				s.outfit.thumbnail.index.to_string()
+			});
+	}
+}
+
 #[derive(Debug, Clone)]
 pub struct SystemObjectState {
 	object: Option<Arc<SystemObject>>,
 }
 
-impl SystemObjectState {}
+impl SystemObjectState {
+	fn outfitter(&mut self) -> Array {
+		let mut a = Array::new();
+		for o in &self
+			.object
+			.as_ref()
+			.unwrap()
+			.landable
+			.as_ref()
+			.unwrap()
+			.outfitter
+		{
+			a.push(Dynamic::from(OutfitState { outfit: o.clone() }));
+		}
+		return a;
+	}
+}
 
 impl CustomType for SystemObjectState {
 	fn build(mut builder: TypeBuilder<Self>) {
 		builder
 			.with_name("SystemObjectState")
+			.with_fn("outfitter", Self::outfitter)
 			//
 			// Get landable name
 			.with_fn("display_name", |s: &mut Self| {
 				s.object
 					.as_ref()
 					.unwrap()
-					.display_name
+					.landable
 					.as_ref()
-					.map(|x| x.to_string())
+					.map(|x| x.display_name.clone())
 					.unwrap_or_else(|| {
-						error!("UI called `name()` on a system object which doesn't provide one");
+						error!("UI called `name()` on a system object which isn't landable");
 						"".to_string()
 					})
 			})
@@ -147,25 +184,32 @@ impl CustomType for SystemObjectState {
 				s.object
 					.as_ref()
 					.unwrap()
-					.desc
+					.landable
 					.as_ref()
-					.map(|x| x.to_string())
+					.map(|x| x.desc.clone())
 					.unwrap_or_else(|| {
-						error!("UI called `name()` on a system object which doesn't provide one");
+						error!("UI called `desc()` on a system object which isn't landable");
 						"".to_string()
 					})
 			})
 			//
 			// Get landable landscape image
 			.with_fn("image", |s: &mut Self| {
-				if let Some(sprite) = &s.object.as_ref().unwrap().image {
-					sprite.index.to_string()
-				} else {
-					error!("UI called `image()` on a system object which doesn't provide one");
+				s.object
+					.as_ref()
+					.unwrap()
+					.landable
+					.as_ref()
+					.map(|x| x.image.index.to_string())
+					.unwrap_or_else(|| {
+						error!("UI called `image()` on a system object which isn't landable");
 						"".to_string()
-				}
+					})
 			})
 			.with_fn("is_some", |s: &mut Self| s.object.is_some())
+			.with_fn("is_landable", |s: &mut Self| {
+				s.object.as_ref().unwrap().landable.is_some()
+			})
 			.with_fn("==", |a: &mut Self, b: Self| match (&a.object, &b.object) {
 				(None, _) => false,
 				(_, None) => false,
@@ -240,7 +284,6 @@ impl CustomType for State {
 			.with_fn("player_ship", Self::player_ship)
 			.with_fn("ships", Self::ships)
 			.with_fn("objects", Self::objects)
-			.with_fn("window_aspect", |s: &mut Self| s.window_aspect)
-			.with_fn("camera_zoom", |s: &mut Self| s.input.camera_zoom);
+			.with_fn("window_aspect", |s: &mut Self| s.window_aspect);
 	}
 }

crates/render/src/ui/camera.rs

@@ -0,0 +1,35 @@
+use nalgebra::Vector2;
+
+#[derive(Debug, Clone)]
+pub(crate) struct Camera {
+	/// The position of the camera, in game units
+	pos: Vector2<f32>,
+
+	/// The height of the viewport, in game units.
+	zoom: f32,
+}
+
+impl Camera {
+	pub fn new() -> Self {
+		Self {
+			pos: Vector2::new(0.0, 0.0),
+			zoom: 500.0,
+		}
+	}
+
+	pub fn set_pos(&mut self, pos: Vector2<f32>) {
+		self.pos = pos
+	}
+
+	pub fn get_pos(&self) -> Vector2<f32> {
+		self.pos
+	}
+
+	pub fn set_zoom(&mut self, zoom: f32) {
+		self.zoom = zoom
+	}
+
+	pub fn get_zoom(&self) -> f32 {
+		self.zoom
+	}
+}

crates/render/src/ui/elements/fpsindicator.rs

@@ -1,10 +1,13 @@
-use glyphon::{Attrs, Buffer, Color, Family, FontSystem, Metrics, Shaping, TextArea, TextBounds};
+use glyphon::{Attrs, Buffer, Color, Family, FontSystem, Metrics, Shaping, TextBounds};
+use std::rc::Rc;
 use winit::window::Window;
 
 use crate::{RenderInput, RenderState};
 
+use super::OwnedTextArea;
+
 pub(crate) struct FpsIndicator {
-	buffer: Buffer,
+	buffer: Rc<Buffer>,
 	update_counter: u32,
 }
 
@@ -21,7 +24,7 @@ impl FpsIndicator {
 		);
 
 		Self {
-			buffer,
+			buffer: Rc::new(buffer),
 			update_counter: 0,
 		}
 	}
@@ -29,26 +32,28 @@ impl FpsIndicator {
 
 impl FpsIndicator {
 	pub fn step(&mut self, input: &RenderInput, font: &mut FontSystem) {
+		let buffer = Rc::get_mut(&mut self.buffer).unwrap();
+
 		if self.update_counter > 0 {
 			self.update_counter -= 1;
 			return;
 		}
 		self.update_counter = 100;
 
-		self.buffer.set_text(
+		buffer.set_text(
 			font,
 			&input.timing.get_string(),
 			Attrs::new().family(Family::Monospace),
 			Shaping::Basic,
 		);
-		self.buffer.shape_until_scroll(font);
+		buffer.shape_until_scroll(font);
 	}
 }
 
 impl<'a, 'b: 'a> FpsIndicator {
-	pub fn get_textarea(&'b self, input: &RenderInput, _window: &Window) -> TextArea<'a> {
-		TextArea {
-			buffer: &self.buffer,
+	pub fn get_textarea(&'b self, input: &RenderInput, _window: &Window) -> OwnedTextArea {
+		OwnedTextArea {
+			buffer: self.buffer.clone(),
 			left: 10.0,
 			top: 400.0,
 			scale: input.ct.config.ui_scale,

crates/render/src/ui/elements/mod.rs

@@ -1,9 +1,38 @@
 mod fpsindicator;
 mod radialbar;
+mod scrollbox;
 mod sprite;
 mod textbox;
 
 pub(super) use fpsindicator::*;
 pub(super) use radialbar::*;
+pub(super) use scrollbox::*;
 pub(super) use sprite::*;
 pub(super) use textbox::*;
+
+use glyphon::{Buffer, Color, TextArea, TextBounds};
+use std::rc::Rc;
+
+/// A hack that lets us easily construct TextAreas
+/// for [`UiTextBox`]es wrapped in Rcs.
+pub struct OwnedTextArea {
+	pub buffer: Rc<Buffer>,
+	pub left: f32,
+	pub top: f32,
+	pub scale: f32,
+	pub bounds: TextBounds,
+	pub default_color: Color,
+}
+
+impl OwnedTextArea {
+	pub fn get_textarea(&self) -> TextArea {
+		TextArea {
+			buffer: &self.buffer,
+			top: self.top,
+			left: self.left,
+			scale: self.scale,
+			bounds: self.bounds,
+			default_color: self.default_color,
+		}
+	}
+}

crates/render/src/ui/elements/radialbar.rs

@@ -6,7 +6,7 @@ use super::super::api::Rect;
 use crate::{ui::api::Color, vertexbuffer::types::RadialBarInstance, RenderInput, RenderState};
 
 #[derive(Debug, Clone)]
-pub struct RadialBar {
+pub struct UiRadialBar {
 	pub name: ImmutableString,
 	rect: Rect,
 	stroke: f32,
@@ -14,7 +14,7 @@ pub struct RadialBar {
 	progress: f32,
 }
 
-impl RadialBar {
+impl UiRadialBar {
 	pub fn new(
 		name: ImmutableString,
 		stroke: f32,
@@ -48,6 +48,4 @@ impl RadialBar {
 			angle: self.progress * TAU,
 		});
 	}
-
-	pub fn step(&mut self, _input: &RenderInput, _state: &mut RenderState) {}
 }

crates/render/src/ui/elements/scrollbox.rs

@@ -0,0 +1,136 @@
+use nalgebra::Vector2;
+use rhai::{Dynamic, ImmutableString};
+use std::{cell::RefCell, collections::HashMap, rc::Rc};
+use winit::window::Window;
+
+use super::{super::api::Rect, OwnedTextArea};
+use crate::{ui::UiElement, InputEvent, RenderInput, RenderState};
+
+#[derive(Debug)]
+pub struct UiScrollbox {
+	pub name: ImmutableString,
+	pub rect: Rect,
+	pub offset: Vector2<f32>,
+	pub elements: HashMap<ImmutableString, Rc<RefCell<UiElement>>>,
+
+	has_mouse: bool,
+}
+
+impl UiScrollbox {
+	pub fn new(name: ImmutableString, rect: Rect) -> Self {
+		Self {
+			name,
+			rect,
+			elements: HashMap::new(),
+			offset: Vector2::new(0.0, 0.0),
+			has_mouse: false,
+		}
+	}
+
+	pub fn add_element(&mut self, e: Rc<RefCell<UiElement>>) {
+		let name = e.borrow().get_name().clone();
+		self.elements.insert(name, e);
+	}
+
+	pub fn remove_element(&mut self, sprite: &ImmutableString) {
+		self.elements.remove(sprite);
+	}
+
+	pub fn step(&mut self, t: f32) {
+		for (_name, e) in &self.elements {
+			match &mut *e.clone().borrow_mut() {
+				UiElement::Sprite(sprite) => sprite.step(t),
+				UiElement::RadialBar(_) => {}
+				UiElement::Text(..) => {}
+				UiElement::Scrollbox(..) => {}
+				UiElement::SubElement { .. } => {}
+			}
+		}
+	}
+
+	pub fn handle_event(
+		&mut self,
+		input: &RenderInput,
+		state: &mut RenderState,
+		event: &InputEvent,
+	) -> Option<Dynamic> {
+		let r = self
+			.rect
+			.to_centered(&state.window, input.ct.config.ui_scale);
+
+		// TODO: handle only if used in event()
+		// i.e, scrollable sprites shouldn't break scrollboxes
+		// First, check if this event is captured by any sub-elements
+		for (_, e) in &mut self.elements {
+			let arg = match &mut *e.borrow_mut() {
+				UiElement::Sprite(sprite) => sprite.handle_event(&input, state, &event),
+				UiElement::Scrollbox(sbox) => sbox.handle_event(&input, state, &event),
+
+				UiElement::RadialBar(_) | UiElement::Text(..) => None,
+
+				// Subelements are intentionally skipped,
+				// they should be handled by their parent's `handle_event` method.
+				UiElement::SubElement { .. } => None,
+			};
+
+			if arg.is_some() {
+				return arg;
+			}
+		}
+
+		// If no inner events were captured, handle self events.
+		match event {
+			InputEvent::MouseMove(pos) => {
+				if r.contains_mouse(state, pos) && !self.has_mouse {
+					self.has_mouse = true;
+				}
+
+				if !r.contains_mouse(state, pos) && self.has_mouse {
+					self.has_mouse = false;
+				}
+			}
+
+			InputEvent::Scroll(x) => {
+				if self.has_mouse {
+					self.offset.y -= x;
+				}
+			}
+
+			_ => return None,
+		}
+
+		return None;
+	}
+}
+
+impl UiScrollbox {
+	pub fn push_to_buffer(&self, input: &RenderInput, state: &mut RenderState) {
+		for (_name, e) in &self.elements {
+			match &*e.clone().borrow() {
+				UiElement::Sprite(sprite) => {
+					sprite.push_to_buffer_with_offset(input, state, self.offset)
+				}
+				UiElement::RadialBar(..) => {}
+				UiElement::Text(..) => {}
+				UiElement::Scrollbox(..) => {}
+				UiElement::SubElement { .. } => {}
+			}
+		}
+	}
+}
+
+// TODO: don't allocate here
+impl<'a> UiScrollbox {
+	pub fn get_textareas(&'a self, input: &RenderInput, window: &Window) -> Vec<OwnedTextArea> {
+		let mut v = Vec::with_capacity(32);
+		for e in self.elements.values() {
+			match &*e.clone().borrow() {
+				UiElement::Text(x) => {
+					v.push(x.get_textarea_with_offset(input, window, self.offset))
+				}
+				_ => {}
+			}
+		}
+		return v;
+	}
+}

crates/render/src/ui/elements/sprite.rs

@@ -2,13 +2,14 @@ use std::sync::Arc;
 
 use super::super::api::Rect;
 use crate::{
-	ui::{api::Color, event::Event},
+	ui::api::{Color, MouseClickEvent, MouseHoverEvent},
 	vertexbuffer::types::UiInstance,
-	RenderInput, RenderState,
+	InputEvent, RenderInput, RenderState,
 };
 use galactica_content::{Sprite, SpriteAutomaton};
 use galactica_util::to_radians;
-use rhai::ImmutableString;
+use nalgebra::Vector2;
+use rhai::{Dynamic, ImmutableString};
 
 #[derive(Debug, Clone)]
 pub struct UiSprite {
@@ -26,8 +27,6 @@ pub struct UiSprite {
 	mask: Option<Arc<Sprite>>,
 	color: Color,
 
-	/// If true, ignore mouse events until click is released
-	waiting_for_release: bool,
 	has_mouse: bool,
 	has_click: bool,
 }
@@ -43,7 +42,6 @@ impl UiSprite {
 			mask: None,
 			has_mouse: false,
 			has_click: false,
-			waiting_for_release: false,
 			preserve_aspect: false,
 		}
 	}
@@ -67,11 +65,23 @@ impl UiSprite {
 	pub fn set_preserve_aspect(&mut self, preserve_aspect: bool) {
 		self.preserve_aspect = preserve_aspect;
 	}
+}
 
+impl UiSprite {
 	pub fn push_to_buffer(&self, input: &RenderInput, state: &mut RenderState) {
+		self.push_to_buffer_with_offset(input, state, Vector2::new(0.0, 0.0))
+	}
+
+	pub fn push_to_buffer_with_offset(
+		&self,
+		input: &RenderInput,
+		state: &mut RenderState,
+		offset: Vector2<f32>,
+	) {
 		let mut rect = self
 			.rect
 			.to_centered(&state.window, input.ct.config.ui_scale);
+		rect.pos += offset;
 
 		if self.preserve_aspect {
 			let rect_aspect = rect.dim.x / rect.dim.y;
@@ -108,55 +118,65 @@ impl UiSprite {
 		});
 	}
 
-	pub fn check_events(&mut self, input: &RenderInput, state: &mut RenderState) -> Event {
+	pub fn handle_event(
+		&mut self,
+		input: &RenderInput,
+		state: &mut RenderState,
+		event: &InputEvent,
+	) -> Option<Dynamic> {
 		let r = self
 			.rect
 			.to_centered(&state.window, input.ct.config.ui_scale);
 
-		if self.waiting_for_release && self.has_mouse && !input.player.input.pressed_leftclick() {
-			self.waiting_for_release = false;
-		}
-
-		if !self.waiting_for_release
-			&& self.has_mouse
-			&& !self.has_click
-			&& input.player.input.pressed_leftclick()
-		{
-			self.has_click = true;
-			return Event::MouseClick;
-		}
-
-		if self.has_mouse && self.has_click && !input.player.input.pressed_leftclick() {
-			self.has_click = false;
-			return Event::MouseRelease;
-		}
-
 		// Release mouse when cursor leaves box
 		if self.has_click && !self.has_mouse {
 			self.has_click = false;
-			return Event::MouseRelease;
 		}
 
-		if r.contains_mouse(input, state) && !self.has_mouse {
-			if input.player.input.pressed_leftclick() {
-				// If we're holding click when the cursor enters,
-				// don't trigger the `Click` event.
-				self.waiting_for_release = true;
-			}
+		match event {
+			InputEvent::MouseMove(pos) => {
+				if r.contains_mouse(state, pos) && !self.has_mouse {
 					self.has_mouse = true;
-			return Event::MouseHover;
+					return Some(Dynamic::from(MouseHoverEvent {
+						enter: true,
+						element: self.name.clone(),
+					}));
 				}
 
-		if !r.contains_mouse(input, state) && self.has_mouse {
-			self.waiting_for_release = false;
+				if !r.contains_mouse(state, pos) && self.has_mouse {
 					self.has_mouse = false;
-			return Event::MouseUnhover;
+					return Some(Dynamic::from(MouseHoverEvent {
+						enter: false,
+						element: self.name.clone(),
+					}));
+				}
 			}
 
-		return Event::None;
+			InputEvent::MouseLeftClick(pressed) => {
+				if self.has_mouse && !self.has_click && *pressed {
+					self.has_click = true;
+					return Some(Dynamic::from(MouseClickEvent {
+						down: true,
+						element: self.name.clone(),
+					}));
 				}
 
-	pub fn step(&mut self, input: &RenderInput, _state: &mut RenderState) {
-		self.anim.step(input.time_since_last_run);
+				if self.has_mouse && self.has_click && !*pressed {
+					self.has_click = false;
+					return Some(Dynamic::from(MouseClickEvent {
+						down: false,
+						element: self.name.clone(),
+					}));
+				}
+			}
+
+			_ => return None,
+		}
+
+		return None;
+	}
+
+	pub fn step(&mut self, t: f32) {
+		self.anim.step(t);
 	}
 }

crates/render/src/ui/elements/textbox.rs

@@ -1,27 +1,28 @@
 use glyphon::{
 	cosmic_text::Align, Attrs, AttrsOwned, Buffer, Color, FamilyOwned, FontSystem, Metrics,
-	Shaping, Style, TextArea, TextBounds, Weight,
+	Shaping, Style, TextBounds, Weight,
 };
 use nalgebra::Vector2;
 use rhai::ImmutableString;
+use std::rc::Rc;
 use winit::window::Window;
 
-use super::super::api::Rect;
+use super::{super::api::Rect, OwnedTextArea};
 use crate::{ui::api, RenderInput};
 
 #[derive(Debug)]
-pub struct TextBox {
+pub struct UiTextBox {
 	pub name: ImmutableString,
 
 	text: String,
 	justify: Align,
 	rect: Rect,
-	buffer: Buffer,
+	buffer: Rc<Buffer>,
 	color: api::Color,
 	attrs: AttrsOwned,
 }
 
-impl TextBox {
+impl UiTextBox {
 	pub fn new(
 		font: &mut FontSystem,
 		name: ImmutableString,
@@ -38,7 +39,7 @@ impl TextBox {
 		Self {
 			name,
 			rect,
-			buffer,
+			buffer: Rc::new(buffer),
 			color,
 			justify: Align::Left,
 			attrs: AttrsOwned::new(Attrs::new()),
@@ -47,14 +48,14 @@ impl TextBox {
 	}
 
 	fn reflow(&mut self, font: &mut FontSystem) {
-		self.buffer
-			.set_text(font, &self.text, self.attrs.as_attrs(), Shaping::Advanced);
+		let buffer = Rc::get_mut(&mut self.buffer).unwrap();
+		buffer.set_text(font, &self.text, self.attrs.as_attrs(), Shaping::Advanced);
 
-		for l in &mut self.buffer.lines {
+		for l in &mut buffer.lines {
 			l.set_align(Some(self.justify));
 		}
 
-		self.buffer.shape_until_scroll(font);
+		buffer.shape_until_scroll(font);
 	}
 
 	pub fn set_text(&mut self, font: &mut FontSystem, text: &str) {
@@ -84,9 +85,19 @@ impl TextBox {
 	}
 }
 
-impl<'a, 'b: 'a> TextBox {
-	pub fn get_textarea(&'b self, input: &RenderInput, window: &Window) -> TextArea<'a> {
-		let rect = self.rect.to_centered(window, input.ct.config.ui_scale);
+impl<'a, 'b: 'a> UiTextBox {
+	pub fn get_textarea(&'b self, input: &RenderInput, window: &Window) -> OwnedTextArea {
+		self.get_textarea_with_offset(input, window, Vector2::new(0.0, 0.0))
+	}
+
+	pub fn get_textarea_with_offset(
+		&'b self,
+		input: &RenderInput,
+		window: &Window,
+		offset: Vector2<f32>,
+	) -> OwnedTextArea {
+		let mut rect = self.rect.to_centered(window, input.ct.config.ui_scale);
+		rect.pos += offset;
 
 		// Glypon works with physical pixels, so we must do some conversion
 		let fac = window.scale_factor() as f32;
@@ -97,8 +108,8 @@ impl<'a, 'b: 'a> TextBox {
 		let corner_sw = corner_ne + rect.dim * fac;
 		let c = self.color.as_array_u8();
 
-		TextArea {
-			buffer: &self.buffer,
+		OwnedTextArea {
+			buffer: self.buffer.clone(),
 			top: corner_ne.y,
 			left: corner_ne.x,
 			scale: input.ct.config.ui_scale,

crates/render/src/ui/event.rs

@@ -1,8 +0,0 @@
-#[derive(Debug, Copy, Clone)]
-pub enum Event {
-	None,
-	MouseClick,
-	MouseRelease,
-	MouseHover,
-	MouseUnhover,
-}

crates/render/src/ui/executor.rs

@@ -1,20 +1,17 @@
 use anyhow::{Context, Result};
 use galactica_content::Content;
-use galactica_system::phys::PhysSimShipHandle;
+use galactica_system::{phys::PhysSimShipHandle, PlayerDirective};
 use galactica_util::rhai_error_to_anyhow;
-use log::debug;
-use rhai::{
-	packages::{BasicArrayPackage, BasicStringPackage, LogicPackage, MoreStringPackage, Package},
-	Dynamic, Engine, ImmutableString, Scope,
-};
+use log::{debug, error};
+use rhai::{Dynamic, Engine, ImmutableString, Scope};
 use std::{cell::RefCell, num::NonZeroU32, rc::Rc, sync::Arc};
+use winit::event::VirtualKeyCode;
 
 use super::{
-	api::{self, MouseClickEvent, MouseHoverEvent, PlayerShipStateEvent},
-	event::Event,
+	api::{self, KeyboardEvent, PlayerShipStateEvent, ScrollEvent},
 	UiConfig, UiElement, UiState,
 };
-use crate::{ui::api::State, RenderInput, RenderState};
+use crate::{ui::api::State, InputEvent, RenderInput, RenderState};
 
 pub(crate) struct UiScriptExecutor {
 	engine: Engine,
@@ -31,14 +28,8 @@ impl UiScriptExecutor {
 		let scope = Scope::new();
 		let elements = Rc::new(RefCell::new(UiState::new(ct.clone(), state)));
 
-		let mut engine = Engine::new_raw();
-
-		// Required for array iteration
-		// We may need to add more packages here later.
-		engine.register_global_module(BasicArrayPackage::new().as_shared_module());
-		engine.register_global_module(LogicPackage::new().as_shared_module());
-		engine.register_global_module(BasicStringPackage::new().as_shared_module());
-		engine.register_global_module(MoreStringPackage::new().as_shared_module());
+		// TODO: document all functions rhai provides
+		let mut engine = Engine::new();
 
 		engine.set_max_expr_depths(0, 0);
 		// Enables custom operators
@@ -64,6 +55,129 @@ impl UiScriptExecutor {
 		(*self.state).borrow().config.clone()
 	}
 
+	pub fn process_input(
+		&mut self,
+		state: &mut RenderState,
+		input: Arc<RenderInput>,
+		event: InputEvent,
+	) -> Result<PlayerDirective> {
+		let current_scene = (*self.state).borrow().get_scene().clone();
+		if current_scene.is_none() {
+			return Ok(PlayerDirective::None);
+		}
+		let mut arg: Option<Dynamic> = None;
+
+		// First, check if this event is captured by any ui elements.
+		for (_, e) in &mut self.state.borrow_mut().elements {
+			arg = match e {
+				UiElement::Sprite(sprite) => sprite.handle_event(&input, state, &event),
+				UiElement::Scrollbox(sbox) => sbox.handle_event(&input, state, &event),
+
+				UiElement::RadialBar(_) | UiElement::Text(..) => None,
+
+				// Subelements are intentionally skipped,
+				// they should be handled by their parent's `handle_event` method.
+				UiElement::SubElement { .. } => None,
+			};
+
+			if arg.is_some() {
+				break;
+			}
+		}
+
+		// If nothing was caught, check global events
+		if arg.is_none() {
+			arg = match event {
+				InputEvent::Scroll(val) => Some(Dynamic::from(ScrollEvent { val })),
+				InputEvent::Keyboard { down, key } => {
+					let str = match key {
+						VirtualKeyCode::A => Some("A"),
+						VirtualKeyCode::B => Some("B"),
+						VirtualKeyCode::C => Some("C"),
+						VirtualKeyCode::D => Some("D"),
+						VirtualKeyCode::E => Some("E"),
+						VirtualKeyCode::F => Some("F"),
+						VirtualKeyCode::G => Some("G"),
+						VirtualKeyCode::H => Some("H"),
+						VirtualKeyCode::I => Some("I"),
+						VirtualKeyCode::J => Some("J"),
+						VirtualKeyCode::K => Some("K"),
+						VirtualKeyCode::L => Some("L"),
+						VirtualKeyCode::M => Some("M"),
+						VirtualKeyCode::N => Some("N"),
+						VirtualKeyCode::O => Some("O"),
+						VirtualKeyCode::P => Some("P"),
+						VirtualKeyCode::Q => Some("Q"),
+						VirtualKeyCode::R => Some("R"),
+						VirtualKeyCode::S => Some("S"),
+						VirtualKeyCode::T => Some("T"),
+						VirtualKeyCode::U => Some("U"),
+						VirtualKeyCode::V => Some("V"),
+						VirtualKeyCode::W => Some("W"),
+						VirtualKeyCode::X => Some("X"),
+						VirtualKeyCode::Y => Some("Y"),
+						VirtualKeyCode::Z => Some("Z"),
+						VirtualKeyCode::Up => Some("up"),
+						VirtualKeyCode::Down => Some("down"),
+						VirtualKeyCode::Left => Some("left"),
+						VirtualKeyCode::Right => Some("right"),
+						VirtualKeyCode::Space => Some("space"),
+						_ => None,
+					};
+					if let Some(str) = str {
+						Some(Dynamic::from(KeyboardEvent {
+							down,
+							key: ImmutableString::from(str),
+						}))
+					} else {
+						None
+					}
+				}
+				_ => None,
+			};
+		}
+
+		if let Some(arg) = arg {
+			self.run_event_callback(state, input, arg)
+		} else {
+			return Ok(PlayerDirective::None);
+		}
+	}
+
+	fn run_event_callback(
+		&mut self,
+		state: &mut RenderState,
+		input: Arc<RenderInput>,
+		arg: Dynamic,
+	) -> Result<PlayerDirective> {
+		let current_scene = (*self.state).borrow().get_scene().clone();
+		if current_scene.is_none() {
+			return Ok(PlayerDirective::None);
+		}
+		let current_scene = current_scene.unwrap();
+		let ct = (*self.state).borrow().ct.clone();
+
+		let d: Dynamic = rhai_error_to_anyhow(self.engine.call_fn(
+			&mut self.scope,
+			ct.config.ui_scenes.get(current_scene.as_str()).unwrap(),
+			"event",
+			(State::new(state, input.clone()), arg.clone()),
+		))
+		.with_context(|| format!("while handling event `{:?}`", arg))
+		.with_context(|| format!("in ui scene `{}`", current_scene))?;
+
+		if d.is::<PlayerDirective>() {
+			return Ok(d.cast());
+		} else if !(d.is_unit()) {
+			error!(
+				"`event()` in UI scene `{current_scene}` returned invalid type `{}`",
+				d
+			)
+		}
+
+		return Ok(PlayerDirective::None);
+	}
+
 	/// Change the current scene
 	pub fn set_scene(&mut self, state: &RenderState, input: Arc<RenderInput>) -> Result<()> {
 		let current_scene = (*self.state).borrow().get_scene().clone();
@@ -87,8 +201,8 @@ impl UiScriptExecutor {
 		let mut elm = self.state.borrow_mut();
 		elm.clear();
 		drop(elm);
-		let ct = (*self.state).borrow().ct.clone();
 
+		let ct = (*self.state).borrow().ct.clone();
 		rhai_error_to_anyhow(
 			self.engine.call_fn(
 				&mut self.scope,
@@ -122,7 +236,6 @@ impl UiScriptExecutor {
 		(*self.state).borrow_mut().step(state, input.clone());
 
 		// Run step() (if it is defined)
-
 		let ast = ct
 			.config
 			.ui_scenes
@@ -158,79 +271,25 @@ impl UiScriptExecutor {
 				true
 			}
 		} {
-			rhai_error_to_anyhow(
-				self.engine.call_fn(
-					&mut self.scope,
-					ct.config
-						.ui_scenes
-						.get(current_scene.as_ref().unwrap().as_str())
-						.unwrap(),
-					"event",
-					(State::new(state, input.clone()), PlayerShipStateEvent {}),
-				),
-			)
-			.with_context(|| format!("while handling player state change event"))
-			.with_context(|| format!("in ui scene `{}`", current_scene.as_ref().unwrap()))?;
+			self.run_event_callback(state, input.clone(), Dynamic::from(PlayerShipStateEvent {}))?;
 		}
 
 		let len = (*self.state).borrow().len();
 		for i in 0..len {
-			let event_arg = match (*self.state).borrow_mut().get_mut_by_idx(i).unwrap() {
+			match (*self.state).borrow_mut().get_mut_by_idx(i).unwrap() {
 				UiElement::Sprite(sprite) => {
-					// Draw and update sprites
-					sprite.step(&input, state);
 					sprite.push_to_buffer(&input, state);
-					let event = sprite.check_events(&input, state);
-
-					match event {
-						Event::None => None,
-
-						Event::MouseClick => Some(Dynamic::from(MouseClickEvent {
-							down: true,
-							element: sprite.name.clone(),
-						})),
-
-						Event::MouseRelease => Some(Dynamic::from(MouseClickEvent {
-							down: false,
-							element: sprite.name.clone(),
-						})),
-
-						Event::MouseHover => Some(Dynamic::from(MouseHoverEvent {
-							enter: true,
-							element: sprite.name.clone(),
-						})),
-
-						Event::MouseUnhover => Some(Dynamic::from(MouseHoverEvent {
-							enter: false,
-							element: sprite.name.clone(),
-						})),
-					}
 				}
 
 				UiElement::RadialBar(x) => {
-					// Draw and update radialbar
-					x.step(&input, state);
 					x.push_to_buffer(&input, state);
-					None
 				}
 
-				UiElement::Text(..) => None,
-			};
+				UiElement::Scrollbox(x) => {
+					x.push_to_buffer(&input, state);
+				}
 
-			if let Some(event_arg) = event_arg {
-				rhai_error_to_anyhow(
-					self.engine.call_fn(
-						&mut self.scope,
-						ct.config
-							.ui_scenes
-							.get(current_scene.as_ref().unwrap().as_str())
-							.unwrap(),
-						"event",
-						(State::new(state, input.clone()), event_arg.clone()),
-					),
-				)
-				.with_context(|| format!("while handling event `{:?}`", event_arg))
-				.with_context(|| format!("in ui scene `{}`", current_scene.as_ref().unwrap()))?;
+				UiElement::SubElement { .. } | UiElement::Text(..) => {}
 			}
 		}
 

crates/render/src/ui/mod.rs

@@ -1,9 +1,9 @@
 mod api;
-mod event;
+mod camera;
+mod elements;
 mod executor;
 mod state;
 
-mod elements;
-
+pub(crate) use camera::*;
 pub(crate) use executor::UiScriptExecutor;
 pub(crate) use state::*;

crates/render/src/ui/state.rs

@@ -1,19 +1,39 @@
 use galactica_content::Content;
-use glyphon::TextArea;
 use log::{debug, error};
 use rhai::ImmutableString;
-use std::collections::HashMap;
-use std::sync::Arc;
+use std::{cell::RefCell, collections::HashMap, rc::Rc, sync::Arc, time::Instant};
 use winit::window::Window;
 
-use super::elements::{FpsIndicator, RadialBar, TextBox, UiSprite};
+use super::{
+	elements::{FpsIndicator, OwnedTextArea, UiRadialBar, UiScrollbox, UiSprite, UiTextBox},
+	Camera,
+};
 use crate::{RenderInput, RenderState};
 
 #[derive(Debug)]
 pub enum UiElement {
 	Sprite(UiSprite),
-	RadialBar(RadialBar),
-	Text(TextBox),
+	RadialBar(UiRadialBar),
+	Text(UiTextBox),
+	Scrollbox(UiScrollbox),
+
+	/// This is a sub-element managed by another element
+	SubElement {
+		parent: ImmutableString,
+		element: Rc<RefCell<UiElement>>,
+	},
+}
+
+impl UiElement {
+	pub fn get_name(&self) -> ImmutableString {
+		match self {
+			Self::Sprite(x) => x.name.clone(),
+			Self::RadialBar(x) => x.name.clone(),
+			Self::Text(x) => x.name.clone(),
+			Self::Scrollbox(x) => x.name.clone(),
+			Self::SubElement { element, .. } => element.borrow().get_name(),
+		}
+	}
 }
 
 #[derive(Clone, Debug)]
@@ -31,8 +51,13 @@ pub(crate) struct UiState {
 
 	show_timings: bool,
 	fps_indicator: FpsIndicator,
+	last_step: Instant,
 
 	pub config: UiConfig,
+
+	/// The player's camera.
+	/// Only used when drawing physics.
+	pub camera: Camera,
 }
 // TODO: remove this
 unsafe impl Send for UiState {}
@@ -52,6 +77,8 @@ impl UiState {
 				show_phys: false,
 				show_starfield: false,
 			},
+			last_step: Instant::now(),
+			camera: Camera::new(),
 		}
 	}
 
@@ -105,15 +132,57 @@ impl UiState {
 	}
 
 	pub fn step(&mut self, state: &mut RenderState, input: Arc<RenderInput>) {
+		let t = self.last_step.elapsed().as_secs_f32();
+		for (_, e) in &mut self.elements {
+			match e {
+				UiElement::Sprite(sprite) => sprite.step(t),
+				UiElement::Scrollbox(sbox) => sbox.step(t),
+				_ => {}
+			}
+		}
+
 		if self.show_timings {
 			self.fps_indicator
 				.step(&input, &mut state.text_font_system.borrow_mut());
 		}
+		self.last_step = Instant::now();
+	}
+
+	pub fn add_element(&mut self, e: UiElement) {
+		self.names.push(e.get_name().clone());
+		self.elements.insert(e.get_name().clone(), e);
+	}
+
+	// Remove an element from this sprite.
+	// This does NOT remove subelements from their parent sprites.
+	pub fn remove_element_incomplete(&mut self, name: &ImmutableString) -> Option<UiElement> {
+		let e = self.elements.remove(name);
+		self.names.retain(|x| *x != name);
+		return e;
+	}
+
+	// Remove an element from this sprite and from all subsprites.
+	pub fn remove_element(&mut self, name: &ImmutableString) {
+		let e = self.elements.remove(name);
+		self.names.retain(|x| *x != name);
+
+		match e {
+			Some(UiElement::SubElement { parent, element }) => {
+				let x = Rc::into_inner(element).unwrap().into_inner();
+				let parent = self.elements.get_mut(&parent).unwrap();
+				match parent {
+					UiElement::Scrollbox(s) => s.remove_element(&x.get_name()),
+					_ => unreachable!("invalid subelement parent"),
+				}
+			}
+			_ => {}
+		}
 	}
 }
 
+// TODO: don't allocate here, return an iterator
 impl<'a> UiState {
-	pub fn get_textareas(&'a mut self, input: &RenderInput, window: &Window) -> Vec<TextArea<'a>> {
+	pub fn get_textareas(&'a self, input: &RenderInput, window: &Window) -> Vec<OwnedTextArea> {
 		let mut v = Vec::with_capacity(32);
 
 		if self.current_scene.is_none() {
@@ -124,9 +193,10 @@ impl<'a> UiState {
 			v.push(self.fps_indicator.get_textarea(input, window))
 		}
 
-		for t in self.elements.values() {
-			match &t {
-				UiElement::Text(x) => v.push(x.get_textarea(input, window)),
+		for e in self.elements.values() {
+			match &e {
+				UiElement::Text(t) => v.push(t.get_textarea(input, window)),
+				UiElement::Scrollbox(b) => v.extend(b.get_textareas(input, window)),
 				_ => {}
 			}
 		}