Merge pull request #84 from JamesTKhan/frustum-culling

Add frustum culling

commons/src/main/com/mbrlabs/mundus/commons/Scene.java

@@ -58,11 +58,10 @@ public class Scene implements Disposable {
     private long id;
 
     public SceneGraph sceneGraph;
+    public SceneSettings settings;
     public MundusEnvironment environment;
     public Skybox skybox;
     public String skyboxAssetId;
-    public float waterHeight = 0f;
-    public WaterResolution waterResolution = WaterResolution.DEFAULT_WATER_RESOLUTION;
 
     public PerspectiveCamera cam;
     public ModelBatch batch;
@@ -80,10 +79,9 @@ public class Scene implements Disposable {
     protected Vector3 clippingPlaneReflection = new Vector3(0.0f, 1f, 0.0f);
     protected Vector3 clippingPlaneRefraction = new Vector3(0.0f, -1f, 0.0f);
 
-    private final float distortionEdgeCorrection = 1f;
-
     public Scene() {
         environment = new MundusEnvironment();
+        settings = new SceneSettings();
 
         cam = new PerspectiveCamera(CameraSettings.DEFAULT_FOV, Gdx.graphics.getWidth(), Gdx.graphics.getHeight());
         cam.position.set(0, 1, -3);
@@ -131,7 +129,7 @@ public void render() {
 
     public void render(float delta) {
         if (fboWaterReflection == null) {
-            Vector2 res = waterResolution.getResolutionValues();
+            Vector2 res = settings.waterResolution.getResolutionValues();
             initFrameBuffers((int) res.x, (int) res.y);
         }
 
@@ -196,7 +194,7 @@ private void initFrameBuffers(int width, int height) {
 
     private void captureReflectionFBO(float delta) {
         // Calc vertical distance for camera for reflection FBO
-        float camReflectionDistance = 2 * (cam.position.y - waterHeight);
+        float camReflectionDistance = 2 * (cam.position.y - settings.waterHeight);
 
         // Save current cam positions
         Vector3 camPos = cam.position.cpy();
@@ -212,7 +210,7 @@ private void captureReflectionFBO(float delta) {
         Gdx.gl.glClear(GL20.GL_COLOR_BUFFER_BIT | GL20.GL_DEPTH_BUFFER_BIT);
         renderSkybox();
         batch.begin(cam);
-        sceneGraph.render(delta, clippingPlaneReflection, -waterHeight + distortionEdgeCorrection);
+        sceneGraph.render(delta, clippingPlaneReflection, -settings.waterHeight + settings.distortionEdgeCorrection);
         batch.end();
         fboWaterReflection.end();
 
@@ -227,7 +225,7 @@ private void captureDepth(float delta) {
         fboDepthRefraction.begin();
         Gdx.gl.glClear(GL20.GL_COLOR_BUFFER_BIT | GL20.GL_DEPTH_BUFFER_BIT);
         depthBatch.begin(cam);
-        sceneGraph.renderDepth(delta, clippingPlaneRefraction, waterHeight + distortionEdgeCorrection, depthShader);
+        sceneGraph.renderDepth(delta, clippingPlaneRefraction, settings.waterHeight + settings.distortionEdgeCorrection, depthShader);
         depthBatch.end();
         fboDepthRefraction.end();
     }
@@ -246,7 +244,7 @@ private void captureRefractionFBO(float delta) {
         Gdx.gl.glClear(GL20.GL_COLOR_BUFFER_BIT | GL20.GL_DEPTH_BUFFER_BIT);
         renderSkybox();
         batch.begin(cam);
-        sceneGraph.render(delta, clippingPlaneRefraction, waterHeight + distortionEdgeCorrection);
+        sceneGraph.render(delta, clippingPlaneRefraction, settings.waterHeight + settings.distortionEdgeCorrection);
         batch.end();
         fboWaterRefraction.end();
     }
@@ -294,8 +292,8 @@ public void setShadowMapShader(ShadowMapShader shadowMapShader) {
      * @param resolution the resolution to use
      */
     public void setWaterResolution(WaterResolution resolution) {
-        this.waterResolution = resolution;
-        Vector2 res = waterResolution.getResolutionValues();
+        settings.waterResolution = resolution;
+        Vector2 res = settings.waterResolution.getResolutionValues();
         initFrameBuffers((int) res.x, (int) res.y);
     }
 

commons/src/main/com/mbrlabs/mundus/commons/SceneSettings.java

@@ -0,0 +1,19 @@
+package com.mbrlabs.mundus.commons;
+
+import com.mbrlabs.mundus.commons.water.WaterResolution;
+
+/**
+ * Settings specific to a Scene.
+ * @author JamesTKhan
+ * @version July 23, 2022
+ */
+public class SceneSettings {
+
+    // Water
+    public float waterHeight = 0f;
+    public final float distortionEdgeCorrection = 1f;
+    public WaterResolution waterResolution = WaterResolution.DEFAULT_WATER_RESOLUTION;
+
+    // Performance
+    public boolean useFrustumCulling = true;
+}

commons/src/main/com/mbrlabs/mundus/commons/dto/SceneDTO.java

@@ -45,6 +45,7 @@ public class SceneDTO implements Json.Serializable {
     private float camFarPlane;
     private float camFieldOfView;
     private float waterHeight;
+    private boolean useFrustumCulling;
     private WaterResolution waterResolution;
 
     public SceneDTO() {
@@ -187,6 +188,14 @@ public float getWaterHeight() {
         return waterHeight;
     }
 
+    public boolean isUseFrustumCulling() {
+        return useFrustumCulling;
+    }
+
+    public void setUseFrustumCulling(boolean useFrustumCulling) {
+        this.useFrustumCulling = useFrustumCulling;
+    }
+
     public void setSkyboxAssetId(String skyboxAssetId) {
         this.skyboxAssetId = skyboxAssetId;
     }

commons/src/main/com/mbrlabs/mundus/commons/scene3d/GameObject.java

@@ -37,6 +37,7 @@ public class GameObject extends SimpleNode<GameObject> implements Iterable<GameO
 
     public String name;
     public boolean active;
+    public boolean scaleChanged;
     private Array<String> tags;
     private Array<Component> components;
 
@@ -169,6 +170,9 @@ public void update(float delta) {
                 }
             }
         }
+
+        // Reset after each update, after components have updated that might need to know about it
+        scaleChanged = false;
     }
 
     /**
@@ -310,6 +314,25 @@ public void remove() {
         }
     }
 
+    @Override
+    public void setLocalScale(float x, float y, float z) {
+        super.setLocalScale(x, y, z);
+        // We track when the scale has changed, for recalculating bounds for things like frustum culling
+        scaleChanged = true;
+    }
+
+    @Override
+    public void scale(Vector3 v) {
+        super.scale(v);
+        scaleChanged = true;
+    }
+
+    @Override
+    public void scale(float x, float y, float z) {
+        super.scale(x,y,z);
+        scaleChanged = true;
+    }
+
     @Override
     public Iterator<GameObject> iterator() {
         return new DepthFirstIterator(this);

commons/src/main/com/mbrlabs/mundus/commons/scene3d/components/CullableComponent.java

@@ -0,0 +1,109 @@
+/*
+ * Copyright (c) 2022. See AUTHORS file.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package com.mbrlabs.mundus.commons.scene3d.components;
+
+import com.badlogic.gdx.graphics.Camera;
+import com.badlogic.gdx.graphics.g3d.ModelInstance;
+import com.badlogic.gdx.math.Vector3;
+import com.badlogic.gdx.math.collision.BoundingBox;
+import com.mbrlabs.mundus.commons.env.lights.DirectionalLight;
+import com.mbrlabs.mundus.commons.scene3d.GameObject;
+import com.mbrlabs.mundus.commons.shadows.ShadowMapper;
+import com.mbrlabs.mundus.commons.utils.LightUtils;
+
+import static com.mbrlabs.mundus.commons.utils.ModelUtils.isVisible;
+
+/**
+ * Components that can be Culled via Frustum Culling should extend
+ * this class and call setDimensions once they have access to a modelInstance as well as super
+ * for render() and update()
+ *
+ * The isCulled value will be set accordingly and components can check if is isCulled == true
+ * before rendering.
+ *
+ * @author JamesTKhan
+ * @version July 18, 2022
+ */
+public abstract class CullableComponent extends AbstractComponent {
+    private final static BoundingBox tmpBounds = new BoundingBox();
+    private final static Vector3 tmpScale = new Vector3();
+    private static DirectionalLight directionalLight;
+
+    public final Vector3 center = new Vector3();
+    public final Vector3 dimensions = new Vector3();
+    public float radius;
+
+    // Is it offscreen?
+    protected boolean isCulled = false;
+    private ModelInstance modelInstance = null;
+
+    public CullableComponent(GameObject go) {
+        super(go);
+
+        // Update out reference on creation of new component
+        directionalLight = LightUtils.getDirectionalLight(go.sceneGraph.scene.environment);
+    }
+
+    @Override
+    public void render(float delta) {
+        if (modelInstance == null) return;
+
+        if (!gameObject.sceneGraph.scene.settings.useFrustumCulling) {
+            isCulled = false;
+            return;
+        }
+
+        boolean visibleToPerspective;
+        boolean visibleToShadowMap = false;
+
+        Camera sceneCam = gameObject.sceneGraph.scene.cam;
+
+        visibleToPerspective = isVisible(sceneCam, modelInstance, center, radius);
+
+        // If not visible to main cam, check if it's visible to shadow map (to prevent shadows popping out)
+        if (!visibleToPerspective) {
+            if (directionalLight.castsShadows && gameObject.sceneGraph.scene.environment.shadowMap instanceof ShadowMapper) {
+                ShadowMapper shadowMapper = (ShadowMapper) gameObject.sceneGraph.scene.environment.shadowMap;
+                visibleToShadowMap = isVisible(shadowMapper.getCam(), modelInstance, center, radius);
+            }
+        }
+
+        isCulled = !visibleToPerspective && !visibleToShadowMap;
+    }
+
+    @Override
+    public void update(float delta) {
+        if (gameObject.scaleChanged) {
+            setDimensions(modelInstance);
+        }
+    }
+
+    protected void setDimensions(ModelInstance modelInstance) {
+        this.modelInstance = modelInstance;
+        modelInstance.calculateBoundingBox(tmpBounds);
+        tmpBounds.getCenter(center);
+        tmpBounds.getDimensions(dimensions);
+        gameObject.getScale(tmpScale);
+        center.scl(tmpScale);
+        dimensions.scl(tmpScale);
+        radius = dimensions.len() / 2f;
+    }
+
+    public boolean isCulled() {
+        return isCulled;
+    }
+}

commons/src/main/com/mbrlabs/mundus/commons/scene3d/components/ModelComponent.java

@@ -35,7 +35,7 @@
  * @author Marcus Brummer
  * @version 17-01-2016
  */
-public class ModelComponent extends AbstractComponent implements AssetUsage, ClippableComponent {
+public class ModelComponent extends CullableComponent implements AssetUsage, ClippableComponent {
 
     protected ModelAsset modelAsset;
     protected ModelInstance modelInstance;
@@ -76,6 +76,8 @@ public void setModel(ModelAsset model, boolean inheritMaterials) {
             }
         }
         applyMaterials();
+
+        setDimensions(modelInstance);
     }
 
     public ObjectMap<String, MaterialAsset> getMaterials() {
@@ -101,6 +103,9 @@ public ModelInstance getModelInstance() {
 
     @Override
     public void render(float delta) {
+        super.render(delta);
+        if (isCulled) return;
+
         modelInstance.transform.set(gameObject.getTransform());
         if (shader != null) {
             gameObject.sceneGraph.scene.batch.render(modelInstance, gameObject.sceneGraph.scene.environment, shader);
@@ -111,6 +116,8 @@ public void render(float delta) {
 
     @Override
     public void renderDepth(float delta, Vector3 clippingPlane, float clipHeight, Shader depthShader) {
+        if (isCulled) return;
+
         if (depthShader instanceof ClippableShader) {
             ((ClippableShader) depthShader).setClippingPlane(clippingPlane);
             ((ClippableShader) depthShader).setClippingHeight(clipHeight);
@@ -139,11 +146,6 @@ public void render(float delta, Vector3 clippingPlane, float clipHeight) {
         render(delta);
     }
 
-    @Override
-    public void update(float delta) {
-
-    }
-
     @Override
     public Component clone(GameObject go) {
         ModelComponent mc = new ModelComponent(go, shader);

commons/src/main/com/mbrlabs/mundus/commons/scene3d/components/TerrainComponent.java

@@ -30,7 +30,7 @@
  * @author Marcus Brummer
  * @version 18-01-2016
  */
-public class TerrainComponent extends AbstractComponent implements AssetUsage, ClippableComponent {
+public class TerrainComponent extends CullableComponent implements AssetUsage, ClippableComponent {
 
     private static final String TAG = TerrainComponent.class.getSimpleName();
 
@@ -49,6 +49,7 @@ public void updateUVs(Vector2 uvScale) {
 
     public void setTerrain(TerrainAsset terrain) {
         this.terrain = terrain;
+        setDimensions(terrain.getTerrain().modelInstance);
     }
 
     public TerrainAsset getTerrain() {
@@ -65,6 +66,8 @@ public void setShader(Shader shader) {
 
     @Override
     public void render(float delta) {
+        super.render(delta);
+        if (isCulled) return;
         gameObject.sceneGraph.scene.batch.render(terrain.getTerrain(), gameObject.sceneGraph.scene.environment, shader);
     }
 
@@ -79,6 +82,8 @@ public void render(float delta, Vector3 clippingPlane, float clipHeight) {
 
     @Override
     public void renderDepth(float delta, Vector3 clippingPlane, float clipHeight, Shader shader) {
+        if (isCulled) return;
+
         if (shader instanceof ClippableShader) {
             ((ClippableShader) shader).setClippingPlane(clippingPlane);
             ((ClippableShader) shader).setClippingHeight(clipHeight);
@@ -87,11 +92,6 @@ public void renderDepth(float delta, Vector3 clippingPlane, float clipHeight, Sh
         gameObject.sceneGraph.scene.depthBatch.render(terrain.getTerrain(), gameObject.sceneGraph.scene.environment, shader);
     }
 
-    @Override
-    public void update(float delta) {
-
-    }
-
     @Override
     public Component clone(GameObject go) {
         // Cant be cloned right now