SketchDiffusionLimitedAggregation.java

package de.hfkbremen.algorithmiccliches.examples;

import de.hfkbremen.algorithmiccliches.octree.Octree;
import de.hfkbremen.algorithmiccliches.octree.OctreeEntity;
import processing.core.PApplet;
import processing.core.PVector;
import teilchen.BasicParticle;
import teilchen.util.Overlap;

import java.util.ArrayList;

public class SketchDiffusionLimitedAggregation extends PApplet {

    private static final int NUMBER_OF_PARTICLES_UNATTACHED = 200;
    private static final int NUMBER_OF_MAX_PARTICLES = 1000;
    private final float mOctreeSize = 150;
    private Octree mOctree;
    private float mRotationZ = 0.1f;
    private int mSphereDetail = 8;

    public void settings() {
        size(1024, 768, P3D);
    }

    public void setup() {
        textFont(createFont("Courier", 11));
        strokeWeight(0.25f);

        mOctree = new Octree(new PVector(-mOctreeSize / 2, -mOctreeSize / 2, -mOctreeSize / 2), mOctreeSize);

        for (int i = 0; i < 270; i += 16) {
            float x = sin(radians(i)) * 50;
            float y = cos(radians(i)) * 50;
            float r = 2.5f + sin(radians(i));
            addInitialParticle(r, x, y, 0);
        }
    }

    public void draw() {
        /* move particles */
        for (OctreeEntity oe : mOctree.entities()) {
            BrownianParticle bp = (BrownianParticle) oe;
            bp.move();
        }

        /* teleport */
        float mBoxSize = mOctreeSize / 2;
        for (OctreeEntity oe : mOctree.entities()) {
            BrownianParticle bp = (BrownianParticle) oe;
            if (bp.position().x > mBoxSize) {
                bp.position().x = -mBoxSize;
            }
            if (bp.position().y > mBoxSize) {
                bp.position().y = -mBoxSize;
            }
            if (bp.position().z > mBoxSize) {
                bp.position().z = -mBoxSize;
            }
            if (bp.position().x < -mBoxSize) {
                bp.position().x = mBoxSize;
            }
            if (bp.position().y < -mBoxSize) {
                bp.position().y = mBoxSize;
            }
            if (bp.position().z < -mBoxSize) {
                bp.position().z = mBoxSize;
            }
        }

        /* maintain particle number */
        final ArrayList<BrownianParticle> mAttachedParticles = new ArrayList<>();
        for (OctreeEntity oe : mOctree.entities()) {
            BrownianParticle bp = (BrownianParticle) oe;
            if (bp.attached()) {
                mAttachedParticles.add(bp);
            }
        }

        int mNumberOfUnattachedParticles = mOctree.entities().size() - mAttachedParticles.size();
        if (mNumberOfUnattachedParticles < NUMBER_OF_PARTICLES_UNATTACHED && mOctree.entities()
                                                                                    .size() < NUMBER_OF_MAX_PARTICLES) {
            addBrownianParticle();
        }

        /* resolve overlap */
        Overlap.resolveOverlap(mAttachedParticles);


        /* --- */
        background(255);
        lights();
        pushMatrix();

        translate(width / 2.0f, height / 2.0f, 0);

        /* rotate */
        mRotationZ += 1.0f / frameRate * 0.1f;
        rotateX(THIRD_PI);
        rotateZ(mRotationZ);
        scale(4);

        /* draw unattached */
        noFill();
        stroke(0);
        for (OctreeEntity oe : mOctree.entities()) {
            BrownianParticle bp = (BrownianParticle) oe;
            if (!bp.attached()) {
                drawCross(bp.position(), bp.radius());
            }
        }

        /* draw attached */
        noStroke();
        sphereDetail(mSphereDetail);
        for (BrownianParticle bp : mAttachedParticles) {
            fill(bp.entity_color);
            pushMatrix();
            translate(bp.position().x, bp.position().y, bp.position().z);
            sphere(bp.radius() * 1.1f);
            popMatrix();
        }

        popMatrix();

        /* draw info */
        fill(0);
        noStroke();
        text("TOTAL    : " + mOctree.entities().size(), 10, 12);
        text("ATTACHED : " + mAttachedParticles.size(), 10, 24);
        text("FPS      : " + frameRate, 10, 36);
    }

    public void keyPressed() {
        switch (key) {
            case '+':
                mSphereDetail++;
                break;
            case '-':
                mSphereDetail--;
                mSphereDetail = max(mSphereDetail, 3);
                break;
            default:
                break;
        }
    }

    private void addInitialParticle(float r, float x, float y, float z) {
        BrownianParticle p = new BrownianParticle(r);
        p.position().set(x, y, z);
        p.attach(true);
        mOctree.add(p);
    }

    private void drawCross(PVector v, float pRadius) {
        line(v.x - pRadius, v.y, v.z, v.x + pRadius, v.y, v.z);
        line(v.x, v.y - pRadius, v.z, v.x, v.y + pRadius, v.z);
        line(v.x, v.y, v.z - pRadius, v.x, v.y, v.z + pRadius);
    }

    private void addBrownianParticle() {
        BrownianParticle mEntity = new BrownianParticle(random(0.5f, 2.5f));
        mEntity.position().x = random(-mOctreeSize / 2, mOctreeSize / 2);
        mEntity.position().y = random(-mOctreeSize / 2, mOctreeSize / 2);
        mEntity.position().z = random(-mOctreeSize / 2, mOctreeSize / 2);
        mOctree.add(mEntity);
    }

    private class BrownianParticle extends BasicParticle implements OctreeEntity {

        private static final float SPEED = 4;
        private static final float SELECT_RADIUS = 20;
        int entity_color = color(191);
        private boolean mAttached = false;

        BrownianParticle(float pRadius) {
            radius(pRadius);
        }

        void move() {
            if (!mAttached) {
                position().x += random(-SPEED, SPEED);
                position().y += random(-SPEED, SPEED);
                position().z += random(-SPEED, SPEED);
                attach();
            }
        }

        void attach(boolean pAttachState) {
            mAttached = pAttachState;
        }

        boolean attach() {
            ArrayList<OctreeEntity> mEntities = mOctree.getEntitesWithinSphere(position(), SELECT_RADIUS);
            if (mEntities != null) {
                for (OctreeEntity mEntity : mEntities) {
                    BrownianParticle m = (BrownianParticle) mEntity;
                    if (m != this & m.attached()) { // only attach to still particles?
                        float mDistance = PVector.dist(position(), m.position());
                        if (mDistance < (radius() + m.radius())) {
                            mAttached = true;
                            return true;
                        }
                    }
                }
            }
            return false;
        }

        boolean attached() {
            return mAttached;
        }
    }

    public static void main(String[] args) {
        PApplet.main(new String[]{SketchDiffusionLimitedAggregation.class.getName()});
    }
}