forked from: forked from: forked from: 流体シミュ高速化/Particle Fluid Optimization
/**
* Copyright Rams4u ( http://wonderfl.net/user/Rams4u )
* MIT License ( http://www.opensource.org/licenses/mit-license.php )
* Downloaded from: http://wonderfl.net/c/dSHu
*/
// forked from hemingway's forked from: forked from: 流体シミュ高速化/Particle Fluid Optimization
// forked from bradsedito's forked from: 流体シミュ高速化/Particle Fluid Optimization
// forked from saharan's 流体シミュ高速化/Particle Fluid Optimization
/*
* 流体シミュ最適化/Particle Fluid Optimization
*
* クリック：水を注ぐ
* Click:Pouring
*/
package {
import flash.utils.*;
import flash.text.*;
import flash.filters.*;
import flash.geom.*;
import flash.events.*;
import flash.display.*;
import net.hires.debug.Stats;
[SWF(frameRate = 60)]
public class SPH extends Sprite {
public static const GRAVITY:Number = 0.02;//重力
public static const RANGE:Number = 12;//影響半径
public static const RANGE2:Number = RANGE * RANGE;//影響半径の二乗
public static const DENSITY:Number = 1;//流体の密度
public static const PRESSURE:Number = 2;//圧力係数
public static const VISCOSITY:Number = 0.1;//粘性係数
public static const NUM_GRIDS:int = 68;//グリッド数(≒ 465 / RANGE)
public static const INV_GRID_SIZE:Number = 1 / (465 / NUM_GRIDS);//グリッドサイズの逆数(≒ 1 / RANGE)
private var img:BitmapData;
private var particles:Vector.<Particle>;
private var numParticles:uint;
private var neighbors:Vector.<Neighbor>;
private var numNeighbors:uint;
private var color:ColorTransform;
private var filter:BlurFilter;
private var count:int;
private var press:Boolean;
private var labP:TextField;
private var grids:Vector.<Vector.<Grid>>;
public function SPH() {
initialize();
}
private function initialize():void {
color = new ColorTransform(0.6, 0.9, 0.95);
filter = new BlurFilter(2, 2, 1);
particles = new Vector.<Particle>();
numParticles = 0;
neighbors = new Vector.<Neighbor>();
numNeighbors = 0;
grids = new Vector.<Vector.<Grid>>(NUM_GRIDS, true);
for(var i:int = 0; i < NUM_GRIDS; i++) {
grids[i] = new Vector.<Grid>(NUM_GRIDS, true);
for(var j:int = 0; j < NUM_GRIDS; j++)
grids[i][j] = new Grid();
}
count = 0;
img = new BitmapData(465, 465, false, 0);
addChild(new Bitmap(img));
addEventListener(Event.ENTER_FRAME, frame);
labP = new TextField();
labP.selectable = false;
var tf:TextFormat = new TextFormat();
tf.color = 0xffffff;
tf.size = 12;
tf.font = "MS UI Gothic";
tf.font = "Tohoma";
labP.defaultTextFormat = tf;
labP.width = 256;
labP.x = 70;
var st:Stats = new Stats();
st.alpha = 0.75;
addChild(st);
addChild(labP);
Wonderfl.capture_delay(10);
stage.addEventListener(MouseEvent.MOUSE_DOWN, function(e:MouseEvent):void {press = true;});
stage.addEventListener(MouseEvent.MOUSE_UP, function(e:MouseEvent):void {press = false;});
}
private function frame(e:Event):void {
if(press) pour();
move();
img.lock();
img.colorTransform(img.rect, color);
img.applyFilter(img, img.rect, new Point(), filter);
draw();
img.unlock();
labP.text = "Particle : " + numParticles;
}
private function draw():void {
var circ:Sprite = new Sprite();
circ.graphics.drawCircle( 0,0,2 );
circ.graphics.beginFill( 0xFFFFFF,1 );
var rect:Rectangle = new Rectangle(0, 0, 2, 2);
for(var i:int = 0; i < numParticles; i++) {
var p:Particle = particles[i];
rect.x = p.x - 1;
rect.y = p.y - 1;
img.fillRect(rect, p.color);
}
}
private function pour():void {
if(count % 2 == 0)
for(var i:int = -4; i <= 4; i++) {
particles[numParticles++] = new Particle(mouseX + i * 8, mouseY);
particles[numParticles - 1].vy = 5;
}
}
private function move():void {
count++;
var i:int;
var j:int;
var dist:Number;
var p:Particle;
updateGrids();
findNeighbors();
calcPressure();
calcForce();
for(i = 0; i < numParticles; i++) {
p = particles[i];
p.move();
}
}
private function updateGrids():void {
var i:int;
var j:int;
for(i = 0; i < NUM_GRIDS; i++)
for(j = 0; j < NUM_GRIDS; j++)
grids[i][j].clear();
for(i = 0; i < numParticles; i++) {
var p:Particle = particles[i];
p.fx = p.fy = p.density = 0;
p.gx = p.x * INV_GRID_SIZE;
p.gy = p.y * INV_GRID_SIZE;
if(p.gx < 0)
p.gx = 0;
if(p.gy < 0)
p.gy = 0;
if(p.gx > NUM_GRIDS - 1)
p.gx = NUM_GRIDS - 1;
if(p.gy > NUM_GRIDS - 1)
p.gy = NUM_GRIDS - 1;
}
}
private function findNeighbors():void {
numNeighbors = 0;
for(var i:int = 0; i < numParticles; i++) {
var p:Particle = particles[i];
var xMin:Boolean = p.gx != 0;
var xMax:Boolean = p.gx != NUM_GRIDS - 1;
var yMin:Boolean = p.gy != 0;
var yMax:Boolean = p.gy != NUM_GRIDS - 1;
findNeighborsInGrid(p, grids[p.gx][p.gy]);
if(xMin) findNeighborsInGrid(p, grids[p.gx - 1][p.gy]);
if(xMax) findNeighborsInGrid(p, grids[p.gx + 1][p.gy]);
if(yMin) findNeighborsInGrid(p, grids[p.gx][p.gy - 1]);
if(yMax) findNeighborsInGrid(p, grids[p.gx][p.gy + 1]);
if(xMin && yMin) findNeighborsInGrid(p, grids[p.gx - 1][p.gy - 1]);
if(xMin && yMax) findNeighborsInGrid(p, grids[p.gx - 1][p.gy + 1]);
if(xMax && yMin) findNeighborsInGrid(p, grids[p.gx + 1][p.gy - 1]);
if(xMax && yMax) findNeighborsInGrid(p, grids[p.gx + 1][p.gy + 1]);
grids[p.gx][p.gy].add(p);
}
}
private function findNeighborsInGrid(pi:Particle, g:Grid):void {
for(var j:int = 0; j < g.numParticles; j++) {
var pj:Particle = g.particles[j];
var distance:Number = (pi.x - pj.x) * (pi.x - pj.x) + (pi.y - pj.y) * (pi.y - pj.y);
if(distance < RANGE2) {
if(neighbors.length == numNeighbors)
neighbors[numNeighbors] = new Neighbor();
neighbors[numNeighbors++].setParticle(pi, pj);
}
}
}
private function calcPressure():void {
for(var i:int = 0; i < numParticles; i++) {
var p:Particle = particles[i];
p.pressure = p.density - DENSITY;
}
}
private function calcForce():void {
var i:int;
for(i = 0; i < numNeighbors; i++) {
var n:Neighbor = neighbors[i];
n.calcForce();
}
}
}
}
class Particle {
public var x:Number;
public var y:Number;
public var gx:int;
public var gy:int;
public var vx:Number;
public var vy:Number;
public var fx:Number;
public var fy:Number;
public var density:Number;
public var pressure:Number;
public var color:int;
public var next:Particle;
public function Particle(x:Number, y:Number) {
this.x = x;
this.y = y;
vx = vy = fx = fy = 0;
color = 0xffffff;
}
public function move():void {
vy += SPH.GRAVITY;
if(density > 0.05) {
vx += fx / density;
vy += fy / density;
}
x += vx;
y += vy;
if(x < 5)
vx += (5 - x) * 0.5 - vx * 0.5;
if(y < 5)
vy += (5 - y) * 0.5 - vy * 0.5;
if(x > 460)
vx += (460 - x) * 0.5 - vx * 0.5;
if(y > 460)
vy += (460 - y) * 0.5 - vy * 0.5;
}
}
class Neighbor {
public var p1:Particle;
public var p2:Particle;
public var distance:Number;
public var nx:Number;
public var ny:Number;
public var weight:Number;
public static const pressure:Number = SPH.PRESSURE;
public static const viscosity:Number = SPH.VISCOSITY;
public function Neighbor() {
}
public function setParticle(p1:Particle, p2:Particle):void {
this.distance = distance;
this.p1 = p1;
this.p2 = p2;
nx = p1.x - p2.x;
ny = p1.y - p2.y;
distance = Math.sqrt(nx * nx + ny * ny);
weight = 1 - distance / SPH.RANGE;
var temp:Number = weight * weight;
temp += temp * weight;
p1.density += temp;
p2.density += temp;
temp = 1 / distance;
nx *= temp;
ny *= temp;
}
public function calcForce():void {
var pressureWeight:Number = weight * (p1.pressure + p2.pressure) * pressure;
if(pressureWeight < 0) pressureWeight = 0;
var viscosityWeight:Number = weight * viscosity;
p1.fx += nx * pressureWeight;
p1.fy += ny * pressureWeight;
p2.fx -= nx * pressureWeight;
p2.fy -= ny * pressureWeight;
var rvx:Number = p2.vx - p1.vx;
var rvy:Number = p2.vy - p1.vy;
p1.fx += rvx * viscosityWeight;
p1.fy += rvy * viscosityWeight;
p2.fx -= rvx * viscosityWeight;
p2.fy -= rvy * viscosityWeight;
}
}
class Grid {
public var particles:Vector.<Particle>;
public var numParticles:int;
public function Grid() {
particles = new Vector.<Particle>;
numParticles = 0;
}
public function clear():void {
numParticles = 0;
}
public function add(p:Particle):void {
particles[numParticles++] = p;
}
}