2D Geometry Test
/**
* Copyright k0rin ( http://wonderfl.net/user/k0rin )
* MIT License ( http://www.opensource.org/licenses/mit-license.php )
* Downloaded from: http://wonderfl.net/c/mEpx
*/
package
{
import flash.display.*;
import flash.events.*;
import flash.filters.GlowFilter;
import flash.geom.*;
import flash.text.*;
public class Main extends Sprite
{
private var frameBuffer:BitmapData = new BitmapData(stage.stageWidth, stage.stageHeight, false);
private var p0:ControlPoint;
private var p1:ControlPoint;
private var p2:ControlPoint;
private var status:TextField;
private var shape:Shape = new Shape();
private var g:Graphics = shape.graphics;
private var caption:TextField = new TextField();
public function Main():void
{
addChild(new Bitmap(frameBuffer));
var shape:Shape = new Shape();
shape.graphics.beginFill(0xAAFFAA, 0.2);
shape.graphics.drawRect(0, 0, 140, 160);
shape.graphics.endFill();
addChild(shape);
status = new TextField();
status.defaultTextFormat = new TextFormat("_sana", 9, 0x000000);
status.autoSize = TextFieldAutoSize.LEFT;
status.selectable = false;
status.x = 5;
status.y = 5;
addChild(status);
p0 = new ControlPoint(this, 60, 340, 0xFF4444);
p1 = new ControlPoint(this, 210, 140, 0x44FF44);
p2 = new ControlPoint(this, 300, 280, 0x4444FF);
caption.defaultTextFormat = new TextFormat("_sans", 14, 0x000000);
caption.width = 0;
caption.autoSize = TextFieldAutoSize.CENTER;
caption.filters = [ new GlowFilter(0xFFFFFF, 1, 6, 6, 30) ];
repaint();
}
public function repaint():void
{
var v1:Point = sub(p1, p0);
var v2:Point = sub(p2, p0);
var p3:Point = add(p1, v2);
var v1Length:Number = norm(v1);
var v2Length:Number = norm(v2);
var dotProduct:Number = dot(v1, v2);
var crossProduct:Number = cross(v1, v2);
var v1cost:Number = dotProduct / v2Length;
var v1sint:Number = crossProduct / v2Length;
var angle:Number = Math.acos(dotProduct / (v1Length * v2Length));
var angle2:Number = Math.asin(crossProduct / (v1Length * v2Length));
var vproj:Point = cut(v2, v1cost);
var vperp:Point = sub(v1, vproj);
function format(value:Number, digits:Number):Number
{
var n:Number = Math.pow(10, digits);
return Math.round(value * n) / n;
}
status.text =
"v1 = [ " + v1.x + ", " + v1.y + " ]\n" +
"v2 = [ " + v2.x + ", " + v2.y + " ]\n" +
"|v1| = " + format(v1Length, 1) + "\n" +
"|v2| = " + format(v2Length, 1) + "\n" +
"v1 / |v1| = ( " + format(v1.x / v1Length, 2) + ", " + format(v1.y / v1Length, 2) + " )\n" +
"v2 / |v2| = ( " + format(v2.x / v2Length, 2) + ", " + format(v2.y / v2Length, 2) + " )\n" +
"v1.v2 = |v1||v2|cosθ = " + dotProduct + "\n" +
"v1xv2 = |v1||v2|sinθ = " + crossProduct + "\n" +
"|v1|cosθ = v1.v2 / |v2| = " + format(v1cost, 1) + "\n" +
"|v1|sinθ = v1xv2 / |v2| = " + format(v1sint, 1) + "\n" +
"θ = cos-1(v1.v2 / |v1||v2|) = " + format(toDegree(angle), 0) + "°\n" +
"θ = sin-1(v1xv2 / |v1||v2|) = " + format(toDegree(angle2), 0) + "°\n";
// rendering
frameBuffer.fillRect(frameBuffer.rect, 0xFFFFFF);
g.clear();
{
g.beginFill(0x000044, 0.05);
moveTo(p0);
lineTo(p1);
lineTo(p3);
lineTo(p2);
lineTo(p0);
g.endFill();
}
frameBuffer.draw(shape);
if (v1Length > 0 && v2Length > 0) {
g.clear();
var n1:Point = minus(mul(normalize(vperp), 60));
g.lineStyle(0, 0xAAAAAA);
drawLine(p1, add(add(p0, vproj), n1));
drawLine(p0, add(p0, vproj));
drawLine(p0, add(p0, n1));
const RECT_SIZE:Number = 10;
if (Math.abs(v1cost) > RECT_SIZE && Math.abs(v1sint) > RECT_SIZE) {
var t:Point = add(p0, vproj); moveTo(t);
addto(t, cut(vperp, RECT_SIZE)); lineTo(t);
addto(t, cut(vproj, -RECT_SIZE)); lineTo(t);
addto(t, cut(vperp, -RECT_SIZE)); lineTo(t);
}
var a0:Point = lerp(p0, add(p0, n1), 0.8);
var a1:Point = add(a0, vproj);
g.lineStyle(0, 0xDDDDDD);
drawLine(a0, a1);
frameBuffer.draw(shape);
drawCaption("|v1|cosθ", midpoint(a0, a1));
}
drawArrow(p0, p1, 0x333333);
drawArrow(p0, p2, 0x333333);
drawCaption("v1xv2", lerp(p0, p3, 0.55));
var sign:Number = (crossProduct > 0) ? 1 : -1;
const OFFSET:Number = 16;
drawCaption("v1", add(midpoint(p0, p1), cut(normal(sub(p1, p0)), sign * OFFSET)));
drawCaption("v2", add(midpoint(p0, p2), cut(normal(sub(p2, p0)), sign * -OFFSET)));
var radius:Number = Math.min(80, Math.min(v1Length, v2Length)) / 4;
var startAngle:Number = getAngle(v1);
var endAngle:Number = getAngle(v2);
if (endAngle - startAngle > Math.PI) {
startAngle += Math.PI * 2;
}
if (startAngle - endAngle > Math.PI) {
endAngle += Math.PI * 2;
}
drawArc(p0, radius, 0x333333, startAngle, endAngle);
drawArc(p0, radius * 0.8, 0x333333, startAngle, endAngle);
drawCaption("|v1|sinθ", midpoint(add(p0, vproj), p1));
}
private function moveTo(p:Point):void
{
g.moveTo(p.x, p.y);
}
private function lineTo(p:Point):void
{
g.lineTo(p.x, p.y);
}
private function drawLine(start:Point, end:Point):void
{
moveTo(start);
lineTo(end);
}
private function drawArrow(start:Point, end:Point, color:uint):void
{
g.clear();
{
g.lineStyle(2, color, 1, false, "normal", null, JointStyle.MITER);
g.moveTo(start.x, start.y);
g.lineTo(end.x, end.y);
var len:Number = distance(start, end);
var arrowLen:Number = Math.min(len, 30) / 3;
var arrowWidth:Number = arrowLen / 3;
if (arrowLen > 0) {
var v:Point = sub(end, start);
var c:Point = sub(end, cut(v, arrowLen));
var l:Point = add(c, cut(normal(v), arrowWidth));
var r:Point = add(c, cut(normal(v), -arrowWidth));
g.beginFill(color);
moveTo(end);
lineTo(l);
lineTo(r);
lineTo(end);
g.endFill();
}
}
frameBuffer.draw(shape);
}
private function drawCaption(text:String, pos:Point):void
{
caption.text = text;
var m:Matrix = new Matrix();
m.translate(pos.x, pos.y - 12);
frameBuffer.draw(caption, m);
}
private function drawArc(center:Point, radius:Number, color:uint, start:Number, end:Number):void
{
g.clear();
{
const SEGMENT:int = 32;
g.lineStyle(2, color);
for (var i:int = 0; i <= SEGMENT; i++) {
var angle:Number = start + (end - start) * (i / SEGMENT);
var x:Number = center.x + Math.cos(angle) * radius;
var y:Number = center.y + Math.sin(angle) * radius;
if (i == 0) {
g.moveTo(x, y);
} else {
g.lineTo(x, y);
}
}
}
frameBuffer.draw(shape);
}
}
}
import flash.geom.Point;
import flash.display.*;
import flash.events.MouseEvent;
class ControlPoint extends Point
{
private var main:Main;
private var sprite:Sprite = new Sprite();
private var g:Graphics = sprite.graphics;
function ControlPoint(main:Main, x:Number, y:Number, color:uint)
{
this.main = main;
this.x = x;
this.y = y;
g.beginFill(color, 0.5);
g.drawCircle(0, 0, 16);
g.endFill();
sprite.x = x;
sprite.y = y;
sprite.buttonMode = true;
sprite.addEventListener(MouseEvent.MOUSE_DOWN, mouseDownHandler);
sprite.addEventListener(MouseEvent.MOUSE_UP, mouseUpHandler);
main.addChild(sprite);
}
private function mouseDownHandler(e:MouseEvent):void
{
sprite.startDrag();
main.stage.addEventListener(MouseEvent.MOUSE_MOVE, mouseMoveHandler);
}
private function mouseUpHandler(e:MouseEvent):void
{
sprite.stopDrag();
main.stage.removeEventListener(MouseEvent.MOUSE_MOVE, mouseMoveHandler);
}
private function mouseMoveHandler(e:MouseEvent):void
{
x = sprite.x;
y = sprite.y;
main.repaint();
e.updateAfterEvent();
}
}
function toDegree(radian:Number):Number
{
return radian * 180 / Math.PI;
}
function toRadian(degree:Number):Number
{
return degree * Math.PI / 180;
}
function minus(v:Point):Point
{
return new Point( -v.x, -v.y);
}
function normal(v:Point):Point
{
return new Point(v.y, -v.x);
}
function norm(v:Point):Number
{
return Math.sqrt(v.x * v.x + v.y * v.y);
}
function normalize(v:Point):Point
{
return div(v, norm(v));
}
function add(n:Point, m:Point):Point
{
return new Point(n.x + m.x, n.y + m.y);
}
function addto(n:Point, m:Point):void
{
n.x += m.x;
n.y += m.y;
}
function sub(n:Point, m:Point):Point
{
return new Point(n.x - m.x, n.y - m.y);
}
function mul(v:Point, f:Number):Point
{
return new Point(v.x * f, v.y * f);
}
function div(v:Point, f:Number):Point
{
return new Point(v.x / f, v.y / f);
}
function dot(a:Point, b:Point):Number
{
return a.x * b.x + a.y * b.y;
}
function cross(a:Point, b:Point):Number
{
return a.x * b.y - a.y * b.x;
}
function distanceSquared(a:Point, b:Point):Number
{
var dx:Number = b.x - a.x;
var dy:Number = b.y - a.y;
return dx * dx + dy * dy;
}
function distance(a:Point, b:Point):Number
{
return Math.sqrt(distanceSquared(a, b));
}
function lerp(n:Point, m:Point, p:Number):Point
{
return add(mul(n, 1 - p), mul(m, p));
}
function midpoint(n:Point, m:Point):Point
{
return new Point((n.x + m.x) * 0.5, (n.y + m.y) * 0.5);
}
function cut(v:Point, len:Number):Point
{
// create a vector of the specified length
return mul(normalize(v), len);
}
function getAngle(v:Point):Number
{
return Math.atan2(v.y, v.x);
}