From 856c3740c76feea6a82cc95b5e190b1ccd165621 Mon Sep 17 00:00:00 2001
From: =?utf8?q?Tomas=20Wenstr=C3=B6m?= <tomas.wenstrom@gmail.com>
Date: Sun, 28 Feb 2021 20:58:13 +0100
Subject: [PATCH] Added a jumping trigger and state

---
 src/core/object/character.rs | 111 +++++++++++++++++++++++++++++--------------
 1 file changed, 75 insertions(+), 36 deletions(-)

diff --git a/src/core/object/character.rs b/src/core/object/character.rs
index 18cb0aa..3d789f2 100644
--- a/src/core/object/character.rs
+++ b/src/core/object/character.rs
@@ -11,10 +11,16 @@ use std::cell::RefCell;
 use std::rc::Rc;
 use time::Duration;
 
+////////// TRIGGER /////////////////////////////////////////////////////////////
+
+trait Trigger {
+    fn update(&mut self, body: &Body, ctrl: &Controller, dt: Duration) -> Option<Box<dyn State>>;
+}
+
 ////////// STATE ///////////////////////////////////////////////////////////////
 
 trait State {
-    fn enter(&self) {}
+    fn enter(&mut self, _body: &mut Body, _ctrl: &Controller, _objects: &mut Objects) {}
     fn exit(&self) {}
     fn update(&mut self, body: &mut Body, ctrl: &Controller, objects: &mut Objects, lvl: &Level, dt: Duration) -> Option<Box<dyn State>>;
 }
@@ -22,29 +28,16 @@ trait State {
 ////////// CHARACTER ///////////////////////////////////////////////////////////
 
 struct Body {
-    pub pos: Point<f64>,
-    pub vel: Point<f64>,
-    pub standing_on: Option<Wall>,
-}
-
-struct StateHolder(Box<dyn State>);
-
-impl StateHolder {
-    pub fn get(&mut self) -> &mut Box<dyn State> {
-	&mut self.0
-    }
-
-    pub fn set(&mut self, state: Box<dyn State>) {
-	self.0.exit();
-	self.0 = state;
-	self.0.enter();
-    }
+    pos: Point<f64>,
+    vel: Point<f64>,
+    standing_on: Option<Wall>,
 }
 
 pub struct Character {
     ctrl: Rc<RefCell<Controller>>,
     body: Body,
-    state: StateHolder, // Plays well with the borrow checker
+    triggers: Vec<Box<dyn Trigger>>,
+    state: Box<dyn State>,
 }
 
 impl Character {
@@ -56,7 +49,8 @@ impl Character {
 		vel: point!(0.0, 0.0),
 		standing_on: None,
 	    },
-	    state: StateHolder(Box::new(FallState)),
+	    triggers: vec!(Box::new(JumpTrigger)),
+	    state: Box::new(FallState),
 	}
     }
 }
@@ -65,8 +59,10 @@ impl Object for Character {
     fn update(&mut self, objects: &mut Objects, lvl: &Level, dt: Duration) -> ObjectState {
 	let ctrl = self.ctrl.borrow();
 
-	if let Some(state) = self.state.get().update(&mut self.body, &ctrl, objects, lvl, dt) {
-	    self.state.set(state);
+	if let Some(state) = self.state.update(&mut self.body, &ctrl, objects, lvl, dt) {
+	    self.state.exit();
+	    self.state = state;
+	    self.state.enter(&mut self.body, &ctrl, objects);
 	}
 
 	match &self.body.standing_on {
@@ -77,11 +73,22 @@ impl Object for Character {
 		    self.body.standing_on = Some(wall);
 		    self.body.pos = pos;
 		    self.body.vel = point!(0.0, 0.0);
-		    self.state.set(Box::new(StandState));
+
+		    self.state.exit();
+		    self.state = Box::new(StandState);
+		    self.state.enter(&mut self.body, &ctrl, objects);
 		}
 	    }
 	}
 
+	for trigger in &mut self.triggers {
+	    if let Some(state) = trigger.update(&self.body, &ctrl, dt) {
+		self.state.exit();
+		self.state = state;
+		self.state.enter(&mut self.body, &ctrl, objects);
+	    }
+	}
+
 	if ctrl.shoot.is_pressed {
 	    use rand::distributions::{Distribution, Normal};
 	    let normal = Normal::new(0.0, 0.1);
@@ -150,26 +157,58 @@ impl State for FallState {
     }
 }
 
-////////// STANDING /////////////////////////////////////////////////////////////
+////////// STANDING ////////////////////////////////////////////////////////////
 
 struct StandState;
 
 impl State for StandState {
-    fn update(&mut self, body: &mut Body, ctrl: &Controller, _objects: &mut Objects, _lvl: &Level, _dt: Duration) -> Option<Box<dyn State>> {
+    fn update(&mut self, body: &mut Body, _ctrl: &Controller, _objects: &mut Objects, _lvl: &Level, _dt: Duration) -> Option<Box<dyn State>> {
+	if let Some(_wall) = &body.standing_on {
+	    body.vel *= 0.9;
+	}
+
+	None
+    }
+}
+
+////////// JUMPING /////////////////////////////////////////////////////////////
+
+struct JumpTrigger;
+
+impl Trigger for JumpTrigger {
+    fn update(&mut self, body: &Body, ctrl: &Controller, _dt: Duration) -> Option<Box<dyn State>> {
+	if body.standing_on.is_some() && ctrl.jump.is_pressed && !ctrl.jump.was_pressed { // this is redundant now because JumpState needs a wall to get starting velocity, but that will probably change
+	    Some(Box::new(JumpState))
+	} else {
+	    None
+	}
+    }
+}
+
+struct JumpState;
+
+impl State for JumpState {
+    fn enter(&mut self, body: &mut Body, ctrl: &Controller, _objects: &mut Objects) {
 	if let Some(wall) = &body.standing_on {
-	    if ctrl.jump.is_pressed && !ctrl.jump.was_pressed {
-		if ctrl.mov.to_point().length() < 0.1 {
-		    body.vel = wall.normal().into();
-		} else {
-		    body.vel = ctrl.mov.to_point();
-		}
-		body.vel *= 5.0;
-		body.pos += body.vel * 0.1;
-		body.standing_on = None;
-		return Some(Box::new(FallState))
+	    if ctrl.mov.to_point().length() < 0.1 {
+		body.vel = wall.normal().into();
 	    } else {
-		body.vel *= 0.9;
+		body.vel = ctrl.mov.to_point();
 	    }
+	    body.vel *= 5.0;
+	    body.pos += body.vel * 0.1;
+	    body.standing_on = None;
+	}
+    }
+
+    fn update(&mut self, body: &mut Body, ctrl: &Controller, _objects: &mut Objects, lvl: &Level, _dt: Duration) -> Option<Box<dyn State>> {
+	body.vel += lvl.gravity;
+	body.pos += body.vel;
+
+	match ctrl.mov.x {
+	    v if v < -0.9 && body.vel.x > -5.0 => { body.vel.x -= 0.5 }
+	    v if v > 0.9 && body.vel.x < 5.0 => { body.vel.x += 0.5 }
+	    _ => {}
 	}
 
 	None
-- 
2.11.0