From 24b6a9d3edaf2a5ddb7a1399cd286716d1a1db13 Mon Sep 17 00:00:00 2001
From: Collin Smith <collinsmith70@gmail.com>
Date: Wed, 20 Nov 2019 00:16:10 -0800
Subject: [PATCH] Fixed Box2D world generation

Fixed Box2D world generation by subtracting tile offset
Added Box2D debug renderer
Disabled RenderSystem debug subtile flag
---
 .../com/riiablo/camera/IsometricCamera.java   |  4 ++
 .../system/debug/Box2DDebugRenderSystem.java  | 45 +++++++++++++++++++
 .../com/riiablo/map/Box2DPhysicsSystem.java   | 10 +++--
 core/src/com/riiablo/map/RenderSystem.java    |  2 +-
 4 files changed, 56 insertions(+), 5 deletions(-)
 create mode 100644 core/src/com/riiablo/engine/system/debug/Box2DDebugRenderSystem.java

diff --git a/core/src/com/riiablo/camera/IsometricCamera.java b/core/src/com/riiablo/camera/IsometricCamera.java
index a4994039..fca7b311 100644
--- a/core/src/com/riiablo/camera/IsometricCamera.java
+++ b/core/src/com/riiablo/camera/IsometricCamera.java
@@ -22,6 +22,10 @@ public class IsometricCamera extends OrthographicCamera {
     toWorld(pixOffset.x, pixOffset.y, tileOffset.setZero());
   }
 
+  public Vector2 getTileOffset(Vector2 dst) {
+    return dst.set(tileOffset);
+  }
+
   @Override
   public void translate(Vector2 vec) {
     translate(vec.x, vec.y);
diff --git a/core/src/com/riiablo/engine/system/debug/Box2DDebugRenderSystem.java b/core/src/com/riiablo/engine/system/debug/Box2DDebugRenderSystem.java
new file mode 100644
index 00000000..f90bc8ba
--- /dev/null
+++ b/core/src/com/riiablo/engine/system/debug/Box2DDebugRenderSystem.java
@@ -0,0 +1,45 @@
+package com.riiablo.engine.system.debug;
+
+import com.badlogic.ashley.core.Engine;
+import com.badlogic.ashley.core.EntitySystem;
+import com.badlogic.gdx.graphics.OrthographicCamera;
+import com.badlogic.gdx.math.Vector3;
+import com.badlogic.gdx.physics.box2d.Box2DDebugRenderer;
+import com.riiablo.map.Box2DPhysicsSystem;
+import com.riiablo.map.RenderSystem;
+
+public class Box2DDebugRenderSystem extends EntitySystem {
+  private static final float BOX2D_ZOOM_FACTOR = 0.04419419f;
+
+  RenderSystem renderSystem;
+  Box2DPhysicsSystem physicsSystem;
+  OrthographicCamera camera;
+  Box2DDebugRenderer renderer;
+
+  public Box2DDebugRenderSystem(RenderSystem renderSystem) {
+    setProcessing(false);
+    this.renderSystem = renderSystem;
+    renderer = new Box2DDebugRenderer();
+    camera = new OrthographicCamera();
+    camera.setToOrtho(true);
+    camera.near = -1024;
+    camera.far  =  1024;
+    camera.rotate(Vector3.X, -60);
+    camera.rotate(Vector3.Z, -45);
+  }
+
+  @Override
+  public void addedToEngine(Engine engine) {
+    assert physicsSystem == null;
+    physicsSystem = engine.getSystem(Box2DPhysicsSystem.class);
+    assert physicsSystem != null;
+  }
+
+  @Override
+  public void update(float delta) {
+    camera.position.set(renderSystem.iso().position, 0);
+    camera.zoom = BOX2D_ZOOM_FACTOR * renderSystem.zoom();
+    camera.update();
+    renderer.render(physicsSystem.world, camera.combined);
+  }
+}
diff --git a/core/src/com/riiablo/map/Box2DPhysicsSystem.java b/core/src/com/riiablo/map/Box2DPhysicsSystem.java
index b3d8828c..fb2459ed 100644
--- a/core/src/com/riiablo/map/Box2DPhysicsSystem.java
+++ b/core/src/com/riiablo/map/Box2DPhysicsSystem.java
@@ -19,6 +19,7 @@ import com.badlogic.gdx.utils.Array;
 import com.badlogic.gdx.utils.Disposable;
 import com.badlogic.gdx.utils.IntMap;
 import com.badlogic.gdx.utils.ObjectMap;
+import com.riiablo.camera.IsometricCamera;
 import com.riiablo.engine.component.Box2DComponent;
 import com.riiablo.engine.component.PositionComponent;
 import com.riiablo.engine.component.VelocityComponent;
@@ -76,15 +77,16 @@ public class Box2DPhysicsSystem extends IntervalIteratingSystem implements Entit
     world.destroyBody(body);
   }
 
-  public void setMap(Map map) {
+  public void setMap(Map map, IsometricCamera iso) {
     if (this.map != map) {
       this.map = map;
-      createBodies();
+      Vector2 tileOffset = iso.getTileOffset(new Vector2()).scl(-1); // offset inverse of tile offset
+      createBodies(tileOffset);
       if (DEBUG) Gdx.app.debug(TAG, "bodies=" + world.getBodyCount());
     }
   }
 
-  private void createBodies() {
+  private void createBodies(Vector2 offset) {
     IntMap<Filter> filters = new IntMap<>();
 
     BodyDef def = new BodyDef();
@@ -116,7 +118,7 @@ public class Box2DPhysicsSystem extends IntervalIteratingSystem implements Entit
             }
 
             int lenY = endY - ty;
-            def.position.set((endX + tx) / 2f, (endY + ty) / 2f);
+            def.position.set((endX + tx) / 2f, (endY + ty) / 2f).add(offset);
 
             PolygonShape shape = new PolygonShape();
             shape.setAsBox(lenX / 2f, lenY / 2f);
diff --git a/core/src/com/riiablo/map/RenderSystem.java b/core/src/com/riiablo/map/RenderSystem.java
index 49e423d3..d90fe323 100644
--- a/core/src/com/riiablo/map/RenderSystem.java
+++ b/core/src/com/riiablo/map/RenderSystem.java
@@ -50,7 +50,7 @@ public class RenderSystem extends EntitySystem {
   private static final boolean DEBUG          = true;
   private static final boolean DEBUG_MATH     = DEBUG && !true;
   private static final boolean DEBUG_BUFFER   = DEBUG && true;
-  private static final boolean DEBUG_SUBTILE  = DEBUG && true;
+  private static final boolean DEBUG_SUBTILE  = DEBUG && !true;
   private static final boolean DEBUG_TILE     = DEBUG && !true;
   private static final boolean DEBUG_CAMERA   = DEBUG && true;
   private static final boolean DEBUG_OVERSCAN = DEBUG && true;