feat: Player's Bow can now shoot Arrows

(physics need adjusting)

core/build.gradle

@@ -1,4 +1,4 @@
-sourceCompatibility = 1.7
+sourceCompatibility = 1.15
 [compileJava, compileTestJava]*.options*.encoding = 'UTF-8'
 
 sourceSets.main.java.srcDirs = [ "src/" ]

core/src/bzh/fainsin/sagittarius/Arrow.java

@@ -0,0 +1,89 @@
+package bzh.fainsin.sagittarius;
+
+import com.badlogic.gdx.graphics.g2d.Batch;
+import com.badlogic.gdx.graphics.g2d.BitmapFont;
+import com.badlogic.gdx.graphics.glutils.ShapeRenderer;
+import com.badlogic.gdx.math.Vector2;
+
+class Arrow extends Entity {
+
+// ---------- ATTRIBUTEs ----------
+
+    private Vector2 velocity = new Vector2();
+    private Vector2 acceleration = new Vector2();
+    private Vector2 force = new Vector2();
+        
+    float TTL = 20;
+    private final float length = 100;
+
+// ---------- CONSTRUCTORs ----------
+
+    Arrow(float angle, float power, Player shooter) {
+        super(shooter.position, 1);
+        this.velocity = new Vector2(power, 0).setAngleDeg(angle);
+        this.acceleration = new Vector2();
+        this.force = computeForce();
+    }
+
+// ---------- METHODs ----------
+ 
+    private Vector2 computeForce() {
+        Vector2 force = new Vector2();
+        for (Planet attractor : SagittariusGame.planetList) {
+            Vector2 diff = attractor.position.cpy().sub(this.position);
+            Vector2 attraction = diff.scl( SagittariusGame.G * attractor.mass / diff.len2()  );
+            force.add(attraction);
+        }
+        return force;
+    }
+
+    private boolean hasLanded() {
+        for (Planet planet : SagittariusGame.planetList) {
+            if (this.distanceTo(planet) < planet.getRadius()) {
+                return true;
+            }
+        }
+        return false;
+    }
+
+    void update(float deltaTime) {
+
+        if (!this.hasLanded()) {
+            integrationVerlet(deltaTime);
+            this.TTL -= deltaTime;
+            this.angle = this.velocity.angleRad();
+        }
+    }
+
+    private void integrationVerlet(float deltaTime) {
+            // Verlet integration
+            // https://gamedev.stackexchange.com/questions/15708/how-can-i-implement-gravity/41917#41917
+
+            // TODO : vectorialiser
+
+            this.acceleration = this.force.cpy();
+
+            this.position.x += deltaTime * ( this.velocity.x + deltaTime * this.acceleration.x / 2 );
+            this.position.y += deltaTime * ( this.velocity.y + deltaTime * this.acceleration.y / 2 );
+
+            this.force = computeForce();
+
+            this.velocity.x += deltaTime * ( this.acceleration.x + this.force.x ) / 2;
+            this.velocity.y += deltaTime * ( this.acceleration.y + this.force.y ) / 2;
+    }
+
+    void render(ShapeRenderer shapeRenderer) {
+        Vector2 tail = new Vector2(-this.length, 0).rotateRad(this.angle).add(this.position);
+        shapeRenderer.line(this.position, tail);
+    }
+
+    void renderDebug(Batch batch, BitmapFont font) {
+        font.draw(batch, "TTL   = " + this.TTL,             this.position.x, this.position.y + font.getCapHeight()*5);
+        font.draw(batch, "pos   = " + this.position,        this.position.x, this.position.y + font.getCapHeight()*4);
+        font.draw(batch, "speed = " + this.velocity,        this.position.x, this.position.y + font.getCapHeight()*3);
+        font.draw(batch, "accel = " + this.acceleration,    this.position.x, this.position.y + font.getCapHeight()*2);
+        font.draw(batch, "force = " + this.force,           this.position.x, this.position.y + font.getCapHeight()*1);
+        font.draw(batch, "angle = " + this.angle,           this.position.x, this.position.y);
+    }
+
+}

core/src/bzh/fainsin/sagittarius/Bow.java

@@ -0,0 +1,63 @@
+package bzh.fainsin.sagittarius;
+
+import com.badlogic.gdx.Gdx;
+import com.badlogic.gdx.Input.Buttons;
+import com.badlogic.gdx.graphics.glutils.ShapeRenderer;
+import com.badlogic.gdx.math.MathUtils;
+import com.badlogic.gdx.math.Vector2;
+
+class Bow {
+
+// ---------- ATTRIBUTEs ----------
+
+	private Player shooter;
+    private boolean aimAssist = false;
+    private boolean pressed = false;
+    private float angle;
+
+    private Vector2 anchor;
+    private Vector2 aim;
+    
+    private float power;
+
+// ---------- CONSTRUCTORs ----------
+
+    Bow(Player shooter, boolean aimAssist) {
+        this.shooter = shooter;
+		this.aimAssist = aimAssist;
+	}
+
+// ---------- METHODs ----------
+
+    void update(double deltaTime) {
+
+        if (Gdx.input.isButtonJustPressed(Buttons.LEFT) && !pressed) {
+            this.anchor = SagittariusGame.worldCursor.cpy();
+            pressed = true;
+        } else if (Gdx.input.isButtonPressed(Buttons.LEFT) && pressed) {
+            computeArrow();
+        } else if (pressed) {
+            SagittariusGame.arrowList.add(getArrow());
+            pressed = false;
+        }
+
+    }
+
+    private Arrow getArrow() {
+        return new Arrow(angle, power, shooter);
+    }
+
+    private void computeArrow() {
+        aim = this.anchor.cpy().sub(SagittariusGame.worldCursor);
+        angle = aim.angleDeg();
+        power = MathUtils.clamp(aim.len(), 0, 1000);
+    }
+
+    public void render(ShapeRenderer shapeRenderer) {
+        if (pressed) {
+            shapeRenderer.line(this.anchor, SagittariusGame.worldCursor);
+			//shapeRenderer.polyline(traj);
+        }
+	}
+
+}

core/src/bzh/fainsin/sagittarius/Entity.java

@@ -16,29 +16,10 @@ abstract class Entity {
 // ---------- CONSTRUCTORs ----------
 
     protected Entity(Vector2 position, float mass) {
-        this.position = position;
+        this.position = position.cpy();
         this.mass = mass;
     }
 
-// ---------- GETs ----------
-
-
-    Vector2 getPosition() {
-        return this.position;
-    }
-    
-    float getMass() {
-        return this.mass;
-    }
-
-    float getAngle() {
-        return this.angle;
-    }
-    
-    Color getColor() {
-        return this.color;
-    }
-
 // ---------- METHODs ----------
 
     /**
@@ -47,7 +28,7 @@ abstract class Entity {
      * @return distance to entity
      */
     float distanceTo(Entity entity) {
-        return this.position.sub(entity.getPosition()).len();
+        return this.position.cpy().sub(entity.position).len();
     }
 
 }

core/src/bzh/fainsin/sagittarius/GameScreen.java

@@ -39,17 +39,17 @@ class GameScreen extends ScreenAdapter {
         Gdx.gl.glClear(GL20.GL_COLOR_BUFFER_BIT);
     }
 
-    private void update(float delta) {
-        SagittariusGame.update(delta);
+    private void update(float deltaTime) {
+        SagittariusGame.update(deltaTime);
         hud.update();
         camera.position.set(WIDTH / 2, HEIGHT / 2, 0);
         camera.update();
     }
 
     @Override
-    public void render(float delta) {
+    public void render(float deltaTime) {
 
-        update(delta);
+        update(deltaTime);
 
         clearScreen();
 
@@ -67,6 +67,11 @@ class GameScreen extends ScreenAdapter {
             player.renderDebug(batch, font);
         }
 
+        // arrows
+        for (Arrow arrow : SagittariusGame.arrowList) {
+            arrow.renderDebug(batch, font);
+        }
+
         batch.end();
 
         // ---------- shapeRenderer ----------
@@ -83,6 +88,11 @@ class GameScreen extends ScreenAdapter {
             player.render(shapeRenderer);
         }
 
+        // arrows
+        for (Arrow arrow : SagittariusGame.arrowList) {
+            arrow.render(shapeRenderer);
+        }
+
         shapeRenderer.end();
 
         // HUD

core/src/bzh/fainsin/sagittarius/HUD.java

@@ -23,7 +23,14 @@ class HUD implements Disposable {
 
     public void render() {
         batch.begin();
+        
+        // framerate
         font.draw(batch, frameRate + " fps", 3, Gdx.graphics.getHeight() - 3);
+        
+        // cursor positions
+        font.draw(batch, "x_r = " + (int) SagittariusGame.screenCursor.x + ", y_r = " + (int) SagittariusGame.screenCursor.y, SagittariusGame.screenCursor.x + 5, Gdx.graphics.getHeight() - SagittariusGame.screenCursor.y + 5);
+        font.draw(batch, "x_g = " + (int) SagittariusGame.worldCursor.x + ", y_g = " + (int) SagittariusGame.worldCursor.y, SagittariusGame.screenCursor.x + 5, Gdx.graphics.getHeight() - SagittariusGame.screenCursor.y + 20);
+        
         batch.end();
     }
 

core/src/bzh/fainsin/sagittarius/Player.java

@@ -6,45 +6,59 @@ import com.badlogic.gdx.graphics.glutils.ShapeRenderer;
 import com.badlogic.gdx.math.MathUtils;
 import com.badlogic.gdx.math.Vector2;
 
-public class Player extends Entity {
+class Player extends Entity {
 
 // ---------- ATTRIBUTEs ----------
 
     private Planet home;
     private final float width = 50;
     private final float height = 100;
+    private Bow bow;
+
+    private Vector2 positionBottom = new Vector2(); // TODO : reorganize, center of mass....
 
 // ---------- CONSTRUCTORs ----------
 
     Player(Planet home) {
-        super(new Vector2(), 1);
+        super(home.position, 1);
         this.home = home;
+        this.bow = new Bow(this, false);
+        this.angle = 45; // TODO : tmp
     }
     
 // ---------- METHODs ----------
 
     void render(ShapeRenderer shapeRenderer) {
         shapeRenderer.setColor(color);
-		shapeRenderer.rect(position.x, position.y, width/2, 0, width, height, 1, 1, angle-90);
+		shapeRenderer.rect(positionBottom.x - width/2, positionBottom.y, width/2, 0, width, height, 1, 1, angle-90);
+        this.bow.render(shapeRenderer);
 	}
 
     void renderDebug(Batch batch, BitmapFont font) {
         font.draw(batch, "x = " + (int) position.x + ", y = " + (int) position.y, position.x, position.y);
     }
 
-    void update(float delta) {
+    void update(float deltaTime) {
 
         computePosition();
 
-        this.angle += 100.0f / home.getRadius();
+        bow.update(deltaTime);
+
+        // this.angle += 100.0f / home.getRadius(); // TODO : debug, remove later
 
     }
 
     void computePosition() {
-        Vector2 homePosition = this.home.getPosition();
+        Vector2 homePosition = this.home.position;
         float homeRadius = this.home.getRadius();
-        this.position.x = homePosition.x + homeRadius*MathUtils.cosDeg(angle) - width/2;
-        this.position.y = homePosition.y + homeRadius*MathUtils.sinDeg(angle);
+        this.position.x = homePosition.x + (homeRadius + height/2)*MathUtils.cosDeg(angle);
+        this.position.y = homePosition.y + (homeRadius + height/2)*MathUtils.sinDeg(angle); // TODO, faire des opérations vectorielles ?
+        this.positionBottom.x = homePosition.x + homeRadius*MathUtils.cosDeg(angle);
+        this.positionBottom.y = homePosition.y + homeRadius*MathUtils.sinDeg(angle);
+    }
+
+    Planet getHome() {
+        return this.home;
     }
 
 }

core/src/bzh/fainsin/sagittarius/SagittariusGame.java

@@ -1,6 +1,7 @@
 package bzh.fainsin.sagittarius;
 
 import java.util.ArrayList;
+import java.util.Iterator;
 
 import com.badlogic.gdx.Game;
 import com.badlogic.gdx.Gdx;
@@ -12,6 +13,9 @@ public class SagittariusGame extends Game {
 
 // ---------- ATTRIBUTEs ----------
 
+	// Constants
+	static final int G = 100;
+
 	// Vectors
 	static Vector2 screenCursor;
 	static Vector2 worldCursor;
@@ -19,6 +23,7 @@ public class SagittariusGame extends Game {
 	// Entities
 	static ArrayList<Planet> planetList;
 	static ArrayList<Player> playerList;
+	static ArrayList<Arrow> arrowList;
 	
 // ---------- METHODs ----------
 
@@ -27,15 +32,17 @@ public class SagittariusGame extends Game {
 		setScreen(new GameScreen());
 		
 		planetList = new ArrayList<Planet>();
-		planetList.add( new Planet(new Vector2(100, 100), 1, 50) );
-		planetList.add( new Planet(new Vector2(400, 400), 1, 100, Color.CYAN) );
+		planetList.add( new Planet(new Vector2(400, 400), 1000, 50) );
+		planetList.add( new Planet(new Vector2(1000, 400), 1000, 100, Color.CYAN) );
 
 		playerList = new ArrayList<Player>();
 		playerList.add( new Player(planetList.get(0)) );
-		playerList.add( new Player(planetList.get(1)) );
+	
+		arrowList = new ArrayList<Arrow>();
+
 	}
 
-	static void update(float delta) {
+	static void update(float deltaTime) {
 
 		// cursors
 		screenCursor = new Vector2(Gdx.input.getX(), Gdx.input.getY());
@@ -44,7 +51,16 @@ public class SagittariusGame extends Game {
 
 		// players
 		for (Player player : playerList) {
-			player.update(delta);
+			player.update(deltaTime);
+		}
+
+		// arrows
+		for (Iterator<Arrow> it = arrowList.iterator(); it.hasNext(); ) {
+			Arrow arrow = it.next();
+			arrow.update(deltaTime);
+			if (arrow.TTL <= 0) {
+				it.remove();
+			}
 		}
 	
 	}

desktop/build.gradle

@@ -1,4 +1,4 @@
-sourceCompatibility = 1.7
+sourceCompatibility = 1.15
 sourceSets.main.java.srcDirs = [ "src/" ]
 sourceSets.main.resources.srcDirs = ["../core/assets"]
 

gradle/wrapper/gradle-wrapper.properties

@@ -1,5 +1,5 @@
 distributionBase=GRADLE_USER_HOME
 distributionPath=wrapper/dists
-distributionUrl=https\://services.gradle.org/distributions/gradle-6.7.1-bin.zip
+distributionUrl=https\://services.gradle.org/distributions/gradle-6.7.1-all.zip
 zipStoreBase=GRADLE_USER_HOME
 zipStorePath=wrapper/dists