範例:透視投影Flash Player 10 以及更新的版本,Adobe AIR 1.5 以及更新的版本 在下列範例中,會示範如何使用透視投影建立 3D 空間。範例中會說明如何透過 projectionCenter 屬性,修改消失點及變更空間的透視投影。這項變更會強迫 focalLength 和 fieldOfView 根據伴隨而來的 3D 空間扭曲執行重新計算。 在本範例中,會執行下列步驟:
當您測試 ProjectionDragger.swf 這個範例時,請將圓圈拖曳至不同的位置。消失點會隨著圓圈移動,並落在您放開圓圈的位置。當您移動投影中心使其遠離舞台中央時,請留意包圍住空間的四個方塊會延伸並開始扭曲。 若要取得此樣本的應用程式檔案,請參閱 www.adobe.com/go/learn_programmingAS3samples_flash_tw。您可以在 Samples/ProjectionDragger 資料夾中找到 ProjectionDragger 應用程式檔案。 package
{
import flash.display.Sprite;
import flash.display.Shape;
import flash.geom.Point;
import flash.events.*;
public class ProjectionDragger extends Sprite
{
private var center : Sprite;
private var boxPanel:Shape;
private var inDrag:Boolean = false;
public function ProjectionDragger():void
{
createBoxes();
createCenter();
}
public function createCenter():void
{
var centerRadius:int = 20;
center = new Sprite();
// circle
center.graphics.lineStyle(1, 0x000099);
center.graphics.beginFill(0xCCCCCC, 0.5);
center.graphics.drawCircle(0, 0, centerRadius);
center.graphics.endFill();
// cross hairs
center.graphics.moveTo(0, centerRadius);
center.graphics.lineTo(0, -centerRadius);
center.graphics.moveTo(centerRadius, 0);
center.graphics.lineTo(-centerRadius, 0);
center.x = 175;
center.y = 175;
center.z = 0;
this.addChild(center);
center.addEventListener(MouseEvent.MOUSE_DOWN, startDragProjectionCenter);
center.addEventListener(MouseEvent.MOUSE_UP, stopDragProjectionCenter);
center.addEventListener( MouseEvent.MOUSE_MOVE, doDragProjectionCenter);
root.transform.perspectiveProjection.projectionCenter = new Point(center.x, center.y);
}
public function createBoxes():void
{
// createBoxPanel();
var boxWidth:int = 50;
var boxHeight:int = 50;
var numLayers:int = 12;
var depthPerLayer:int = 50;
// var boxVec:Vector.<Shape> = new Vector.<Shape>(numLayers);
for (var i:int = 0; i < numLayers; i++)
{
this.addChild(createBox(150, 50, (numLayers - i) * depthPerLayer, boxWidth, boxHeight, 0xCCCCFF));
this.addChild(createBox(50, 150, (numLayers - i) * depthPerLayer, boxWidth, boxHeight, 0xFFCCCC));
this.addChild(createBox(250, 150, (numLayers - i) * depthPerLayer, boxWidth, boxHeight, 0xCCFFCC));
this.addChild(createBox(150, 250, (numLayers - i) * depthPerLayer, boxWidth, boxHeight, 0xDDDDDD));
}
}
public function createBox(xPos:int = 0, yPos:int = 0, zPos:int = 100, w:int = 50, h:int = 50, color:int = 0xDDDDDD):Shape
{
var box:Shape = new Shape();
box.graphics.lineStyle(2, 0x666666);
box.graphics.beginFill(color, 1.0);
box.graphics.drawRect(0, 0, w, h);
box.graphics.endFill();
box.x = xPos;
box.y = yPos;
box.z = zPos;
return box;
}
public function startDragProjectionCenter(e:Event)
{
center.startDrag();
inDrag = true;
}
public function doDragProjectionCenter(e:Event)
{
if (inDrag)
{
root.transform.perspectiveProjection.projectionCenter = new Point(center.x, center.y);
}
}
public function stopDragProjectionCenter(e:Event)
{
center.stopDrag();
root.transform.perspectiveProjection.projectionCenter = new Point(center.x, center.y);
inDrag = false;
}
}
}
若要執行更複雜的透視投影,請使用 Matrix3D 類別。 |
|