Question

我用新的fp10绘图api和drawtriangles搞砸了一下。我创造了一些我觉得有点酷的东西，虽然我似乎无法让uv-mapping按照我想要的方式工作。因为我只是在z / y方向上移动点，所以我没有和z值一起计算uv。虽然位图纹理变形了。我试图用x和y来计算一个“假的”z值，但由于我的数学技能很糟糕，我无法让它真正起作用。

我在下面拼凑了一些小样本（代码显然需要清理，但是当我按照我的意愿工作时，我会担心这一点）。

在这个例子中，z-val将始终为1，并且不会进行透视修复。所以我真的需要你的帮助来弄清楚我如何能够计算出我的x和y点并将它们变成一个“虚假的”z点并使用它来避免地图/纹理中的扭曲。

谢谢！

  package {

  import flash.display.BitmapData;
  import flash.display.Sprite;
  import flash.events.Event;
  import flash.geom.Point;

  public class Debug extends Sprite{

   private var bitmapData:BitmapData;

   private var plane:Plane;
   private var container:Sprite;

   public function Debug(){
    bitmapData = new slask(0, 0);

    container = new Sprite();
    container.x = 200;
    container.y = 200;
    this.addChild(container);

    plane = new Plane(bitmapData);
    container.addChild(plane);

    this.addEventListener(Event.ENTER_FRAME, render);
   }

   function render(e:Event):void{
    var mp:Point = new Point(container.mouseX, container.mouseY);
    plane.render(mp);
   }
  }

 }

 import flash.display.Sprite;
 import flash.geom.Point;
 import flash.geom.Vector3D;
 import flash.display.BitmapData;

 class Plane extends Sprite {

  private var indices:Vector.<int> = new Vector.<int>();  
  private var vertices:Vector.<Number>;
  private var uvtData:Vector.<Number>;

  private var focalLength:Number = 200;
  private var bitmapData:BitmapData;
  private var verts:Array;

  public function Plane(bmp:BitmapData){   
   bitmapData = bmp;

   verts = new Array();
   var sizes:Array = [
         {x: 0, y: 0, z:0},
         {x: 200, y: 0, z:0},
         {x: 0, y: 200, z:0},         
         {x: 200, y: 200, z:0}
        ];

   for(var i:int = 0; i < 4; i++){
    verts[i] = new Vert(sizes[i].x, sizes[i].y, sizes[i].z);
   }

   indices.push(0,1,2, 1,2,3);
  }

  public function render( mousePoint:Point ):void {
   for(var i:int = 0; i < 4; i++){
    verts[i].update(mousePoint);
   }
   drawMe();
  }

  private function drawMe():void {
   vertices = Vector.<Number>([]);
   uvtData = Vector.<Number>([]);

   var t1:Number = focalLength/(focalLength + verts[0].z);
   var t2:Number = focalLength/(focalLength + verts[1].z);
   var t3:Number = focalLength/(focalLength + verts[2].z);
   var t4:Number = focalLength/(focalLength + verts[3].z);

   vertices.push( verts[0].x*t1, verts[0].y*t1,
       verts[1].x*t2, verts[1].y*t2, 
       verts[2].x*t3, verts[2].y*t3, 
       verts[3].x*t4, verts[3].y*t4);

   uvtData.push(0,0,t1, 1,0,t2, 0,1,t3, 1,1,t4);

   this.graphics.clear();
   this.graphics.lineStyle(1, 0xFF0000);
   this.graphics.beginBitmapFill(bitmapData, null, false, true);
   this.graphics.drawTriangles(vertices, indices, uvtData);
  }

 }

 class Vert extends Vector3D {

  private var vx:Number = 0;
  private var vy:Number = 0; 

  private var orgX:Number;
  private var orgY:Number;  

  public function Vert(xx:int, yy:int, zz:int){
   x = orgX = xx;
   y = orgY = yy;
   z = zz;
  }

  public function update( mousePoint:Point ):void {
   var vertPoint:Point = new Point(x, y);
   var distance:Number = Point.distance(mousePoint, vertPoint);

   var dx:Number;
   var dy:Number;

   if (distance < 225) {
    var diff:Number = -distance * (225 - distance) / 225;
    var radian:Number = Math.atan2(mousePoint.y - orgY, mousePoint.x - orgX);
    var diffPoint:Point = Point.polar(diff*2, radian);
    dx = orgX + diffPoint.x;
    dy= orgY + diffPoint.y;
   } else {
    dx = orgX;
    dy = orgY;
   }

   vx += (dx - x) * 0.02;
   vy += (dy - y) * 0.02;
   vx *= 0.9;
   vy *= 0.9;

   x += vx;
   y += vy;
  }

 }

Answer 1

Flash有一个漂亮的实用功能Utils3D.projectVectors（）。您将所有数据传递给它，并计算uvt坐标的缺失值。这是文档说的：

数字向量，其中每三个数字代表u，v和 uvt数据的元素。 u和v是纹理坐标每个预测点。 t值是投影深度值，在视图或眼睛空间中从眼睛到Vector3D对象的距离。您应该预先分配Vector并指定u和v值。的的 projectVectors方法填充每个投影点的t值。

http://help.adobe.com/en_US/FlashPlatform/reference/actionscript/3/flash/geom/Utils3D.html#projectVectors()

AS3 fp10 drawtriangles和uvmapping，当没有z-val时

1 个答案: