// UpDownRoad.as // Display a 3d updown road with 3d particles. package { import flash.display.Sprite; import flash.display.BitmapData; import flash.display.Bitmap; import flash.geom.Rectangle; import flash.events.Event; [SWF(width="465", height="465", backgroundColor="0x000000", frameRate="30")] public class UpDownRoad extends Sprite { private const SCREEN_WIDTH:int = 465; private const SCREEN_HEIGHT:int = 465; private const DRAWN_PARTICLES_MAX_COUNT:int = 2000; private const PROJECTION_RATIO:Number = 128; private const LOD_DISTANCE:Number = 200; private const MAX_DEPTH:Number = 500; private const ROAD_SPACING:Number = 5; private const ROAD_WIDTH:Number = 64; private const ROAD_HEIGHT:Number = 6; private const SIGHT_HEIGHT:Number = 30; private const BACKGROUND_BOX_SIZE:int = 16; private const BACKGROUND_R:int = 0x88; private const BACKGROUND_G:int = 0xcc; private const BACKGROUND_B:int = 0xff; private var buffer:BitmapData = new BitmapData(SCREEN_WIDTH, SCREEN_HEIGHT, false, 0); private var rect:Rectangle = new Rectangle; private var roads:Vector.<Road> = new Vector.<Road>; private var particles:Vector.<Particle> = new Vector.<Particle>; private var drawnParticles:Vector.<DrawnParticle> = new Vector.<DrawnParticle>; private var dpIndex:int; private var viewpoint:Vector3 = new Vector3; private var yaw:Number, pitch:Number, roll:Number; private var offset:Vector3 = new Vector3; private var carPosIndex:Number; private var roadIndex:int; public function UpDownRoad() { addChild(new Bitmap(buffer)); yaw = pitch = roll = 0; createRoad(); for (var i:int = 0; i < DRAWN_PARTICLES_MAX_COUNT; i++) drawnParticles.push(new DrawnParticle); carPosIndex = roads.length - 10; addEventListener(Event.ENTER_FRAME, onEnterFrame); } private function onEnterFrame(evt:Event):void { buffer.fillRect(buffer.rect, 0x99ffdd); carPosIndex += 1.7; if (carPosIndex >= roads.length) carPosIndex -= roads.length; var cpi:int = carPosIndex; var ncpi:int = carPosIndex + 1; if (ncpi >= roads.length) ncpi -= roads.length; var co:Number = carPosIndex - cpi; var rp:Vector3 = roads[cpi].pos; var nrp:Vector3 = roads[ncpi].pos; viewpoint.x += (rp.x * (1 - co) + nrp.x * co - viewpoint.x) * 0.2; viewpoint.y += (rp.y * (1 - co) + nrp.y * co - viewpoint.y - SIGHT_HEIGHT) * 0.2; viewpoint.z += (rp.z * (1 - co) + nrp.z * co - viewpoint.z) * 0.2; var oa:Number = roads[ncpi].angle - roads[cpi].angle; oa = normalizeAngle(oa); oa = roads[cpi].angle + oa * co - yaw; oa = normalizeAngle(oa); yaw += oa * 0.1; yaw = normalizeAngle(yaw); pitch += ((roads[cpi].upDown * (1 - co) + roads[ncpi].upDown * co) * 0.5 - pitch) * 0.2; roll += (-oa * 0.7 - roll) * 0.1; drawBackground(); dpIndex = 0; for each (var p:Particle in particles) drawParticle(p); drawnParticles.sort(sortOnZ); function sortOnZ(v1:DrawnParticle, v2:DrawnParticle):Number { if (v1.pos.z < v2.pos.z) return 1; else if (v1.pos.z > v2.pos.z) return -1; else return 0; } for (var i:int = 0; i < dpIndex; i++) { var dp:DrawnParticle = drawnParticles[i]; rect.x = dp.pos.x - dp.width; rect.y = dp.pos.y - dp.height; rect.width = dp.width * 2; rect.height = dp.height * 2; buffer.fillRect(rect, dp.color); } } private function drawParticle(p:Particle):void { offset.x = p.pos.x - viewpoint.x; offset.y = p.pos.y - viewpoint.y; offset.z = p.pos.z - viewpoint.z; offset.rotationYaw(yaw); offset.rotationPitch(pitch); offset.rotationRoll(roll); if (offset.z < -10 || offset.z > MAX_DEPTH) return; if (p.detail != null && offset.length < LOD_DISTANCE) { for each (var pp:Particle in p.detail) drawParticle(pp); return; } if (offset.z < 1 || p.width <= 0) return; var ar:Number = 1.0 - offset.z / MAX_DEPTH; if (ar < 0) return; var dp:DrawnParticle = drawnParticles[dpIndex]; var zr:Number = 1.0 / offset.z * PROJECTION_RATIO; dp.pos.x = offset.x * zr + SCREEN_WIDTH / 2; dp.pos.y = offset.y * zr + SCREEN_HEIGHT / 2; dp.pos.z = offset.z; dp.width = p.width * zr; dp.height = p.height * zr; dp.color = createColor(p.r, p.g, p.b, 250 * ar); dpIndex++; } private function createColor(r:int, g:int, b:int, a:int):int { return int((r * a + BACKGROUND_R * (256 - a)) / 256) * 0x10000 + int((g * a + BACKGROUND_G * (256 - a)) / 256) * 0x100 + int((b * a + BACKGROUND_B * (256 - a)) / 256); } private function drawBackground():void { offset.x = 0; offset.y = 0; offset.z = 99999; offset.rotationPitch(pitch); var zr:Number = 1.0 / offset.z * PROJECTION_RATIO; var bc:int = SCREEN_WIDTH / BACKGROUND_BOX_SIZE + 1; var bx:Number, by:Number; var vby:Number = BACKGROUND_BOX_SIZE * Math.sin(roll); var bh:Number, bby:Number; for (var j:int = 0; j < 3; j++) { switch (j) { case 0: { bh = 8; bby = 0; break; } case 1: { bh = 16; bby = 16; break; } case 2: { bh = SCREEN_HEIGHT / 3; bby = 48; break; } } bx = SCREEN_WIDTH / 2 - BACKGROUND_BOX_SIZE * bc / 2; by = offset.y * zr + SCREEN_HEIGHT / 2 - vby * bc / 2 + bby + bh; rect.width = BACKGROUND_BOX_SIZE; rect.height = bh * 2; for (var i:int = 0; i < bc; i++) { rect.x = bx - BACKGROUND_BOX_SIZE / 2; rect.y = by - bh; buffer.fillRect(rect, createColor(0x88 - j * 0x33, 0x88 - j * 0x33, 0xff, 255)); bx += BACKGROUND_BOX_SIZE; by += vby; } } } private var roadPattern:Array = [20, 0, 0.2, 1, 16, 0, -3, 0, 16, 0, 3, 0, 80, 0.05, 0.05, 1, 90, 0, 0, 0, 80, -0.05, -1.0, 1, 20, 0, 1.75, 1]; private function createRoad():void { var r:Road = new Road; var a:Number = 0; var ud:Number = roadPattern[2]; r.angle = a; r.upDown = ud; var c:int; var ta:Number, tud:Number; var polePattern:int; var i:int; roadIndex = 0; for (i = 0; i < roadPattern.length; i += 4) { c = roadPattern[i]; ta = roadPattern[i + 1]; tud = roadPattern[i + 2]; polePattern = roadPattern[i + 3]; for (var j:int = 0; j < c; j++) { a += (ta - a) * 0.2; ud += (tud - ud) * 0.1; r.angle += a; r.angle = normalizeAngle(r.angle); r.upDown = ud; addRoadAndPole(r, polePattern); r = getNextRoad(r); } } c = Math.sqrt(r.pos.x * r.pos.x + r.pos.z * r.pos.z) / ROAD_SPACING; var vrp:Vector3 = new Vector3; vrp.x = -r.pos.x / c; vrp.y = -r.pos.y / c; vrp.z = -r.pos.z / c; var va:Number = -r.angle / c; var vud:Number = -r.upDown / c; for (i = 0; i < c; i++) { addRoadAndPole(r, polePattern); var nr:Road = new Road; nr.pos.x = r.pos.x + vrp.x; nr.pos.y = r.pos.y + vrp.y; nr.pos.z = r.pos.z + vrp.z; nr.angle = r.angle + va; nr.upDown = r.upDown + vud; r = nr; } } private function addRoadAndPole(r:Road, polePattern:int):void { addRoadParticles(r); roads.push(r); if (polePattern > 0 && roadIndex % 7 == 0) { addPoleParticles(r); } roadIndex++; } private function getNextRoad(r:Road):Road { var nr:Road = new Road; nr.pos.x = r.pos.x + Math.sin(r.angle) * ROAD_SPACING; nr.pos.z = r.pos.z + Math.cos(r.angle) * ROAD_SPACING; nr.pos.y = r.pos.y + Math.sin(r.upDown) * ROAD_SPACING; nr.angle = r.angle; nr.upDown = r.upDown; return nr; } private function addRoadParticles(r:Road):void { for (var j:int = 0; j < 3; j++) { var p:Particle = new Particle; var ox:Number = Math.cos(r.angle) * ROAD_WIDTH / 3 * 2; var oz:Number = -Math.sin(r.angle) * ROAD_WIDTH / 3 * 2; p.pos.x = r.pos.x + ox * (j - 1); p.pos.y = r.pos.y; p.pos.z = r.pos.z + oz * (j - 1); p.width = ROAD_WIDTH / 3 * 1.05; p.height = ROAD_HEIGHT; p.detail = new Vector.<Particle>; var pc:int = p.width / p.height + 2; ox = Math.cos(r.angle) * p.width / pc * 2; oz = -Math.sin(r.angle) * p.width / pc * 2; var c:int = 0; var i:int; var pp:Particle; for (i = 0; i < pc; i++) { pp = new Particle; pp.pos.x = p.pos.x + ox * (i - pc / 2); pp.pos.y = p.pos.y; pp.pos.z = p.pos.z + oz * (i - pc / 2); pp.width = pp.height = p.height; pp.r = pp.g = pp.b = 190 + Math.random() * 30; c += pp.r; pp.detail = null; p.detail.push(pp); } p.r = p.g = p.b = c / pc; particles.push(p); if (roadIndex % 3 == 0 && j != 1) { pp = new Particle; pp.pos.x = p.pos.x + ox * pc / 2 * 1.2 * (j - 1); pp.pos.y = p.pos.y - p.height * 0.5; pp.pos.z = p.pos.z + oz * pc / 2 * 1.2 * (j - 1); pp.width = p.height; pp.height = p.height * 0.6; pp.r = pp.g = pp.b = 32; pp.detail = null; particles.push(pp); } } } private function addPoleParticles(r:Road):void { for (var i:int = 0; i < 2; i++) { var p:Particle = new Particle; p.width = 4; p.height = 36; p.pos.x = r.pos.x - Math.cos(r.angle) * ROAD_WIDTH * (i * 2 - 1) * 1.1; p.pos.y = r.pos.y - p.height / 2; p.pos.z = r.pos.z + Math.sin(r.angle) * ROAD_WIDTH * (i * 2 - 1) * 1.1; p.r = 250; p.g = 60; p.b = 60; p.detail = new Vector.<Particle>; for (var j:int = 0; j < 8; j++) { var pp:Particle = new Particle; pp.pos.x = p.pos.x; pp.pos.y = p.pos.y - j * p.height / 8; pp.pos.z = p.pos.z; pp.width = p.width; pp.height = p.height / 8; pp.r = p.r; pp.g = p.g; pp.b = p.b; pp.detail = null; p.detail.push(pp); } particles.push(p); } } private function normalizeAngle(v:Number):Number { if (v > Math.PI) return v - Math.PI * 2; else if (v < -Math.PI) return v + Math.PI * 2; else return v; } } } class Road { public var pos:Vector3 = new Vector3; public var angle:Number, upDown:Number; } class Particle { public var pos:Vector3 = new Vector3; public var width:Number; public var height:Number; public var r:int, g:int, b:int; public var detail:Vector.<Particle>; } class DrawnParticle { public var pos:Vector3 = new Vector3; public var width:Number; public var height:Number; public var color:int; } class Vector3 { public var x:Number = 0; public var y:Number = 0; public var z:Number = 0; public function rotationYaw(v:Number):void { var sv:Number = Math.sin(v); var cv:Number = Math.cos(v); var rx:Number = cv * x - sv * z; z = sv * x + cv * z; x = rx; } public function rotationPitch(v:Number):void { var sv:Number = Math.sin(v); var cv:Number = Math.cos(v); var ry:Number = cv * y - sv * z; z = sv * y + cv * z; y = ry; } public function rotationRoll(v:Number):void { var sv:Number = Math.sin(v); var cv:Number = Math.cos(v); var rx:Number = cv * x - sv * y; y = sv * x + cv * y; x = rx; } public function get length():Number { return Math.sqrt(x * x + y * y + z * z); } }