mth

// Code is a modification of code from
// http://www.flashandmath.com/flashcs4/cs4simple3d/index.html

// http://stackoverflow.com/questions/1317992/how-to-rotate-gradient-along-with-sides-of-3d-cube-un-flash-actionscropt-3-0

import fl.events.SliderEvent;
var numVertices:int = 8;
var numFaces:int = 6;
var objRad:Number = 70;
var vertsVec:Vector.<Vector3D> = new Vector.<Vector3D>();
var facesVec:Vector.<Array> = new Vector.<Array>();
//'fLen' is reponsible for perspective distortion: the larger fLen the less distortion.
var fLen:Number = 500;
//We adjust the initial position of the slider that changes perspective.
perspSlider.value = fLen;

var spBoard:Sprite = new Sprite();
this.addChild(spBoard);
spBoard.x = 180;
spBoard.y = 205;
spBoard.filters = [ new DropShadowFilter() ];
//shBack is the black background drawn by the function 'drawBack'.
var shBack:Shape = new Shape();
spBoard.addChild(shBack);
drawBack();

var spObject:Sprite = new Sprite();
var spObjImage:Sprite = new Sprite();
spBoard.addChild(spObjImage);

spObject.rotationX = 0;
spObject.rotationY = 0;
spObject.rotationZ = 0;

var doRotate:Boolean = false;
var prevX:Number;
var prevY:Number;

var facesColors:Array = [0xFFFFCC,
                        0x00FF66,
                        0x0066FF,
                        0x33FFFF,
                        0x9A7DDF,
                        0xFFCCFF];

//Type of Gradient we will be using
var fType:String = GradientType.LINEAR;
//Colors of our gradient in the form of an array
//var colors:Array = [ 0xB4E1E7, 0xEABBCB ];
var colors:Array = [[0x00FF00, 0x004400],
                    [0xFFFF00, 0xFF4400],
                    [0xAAFFAA, 0xFF44AA],
                    [0xCCFF00, 0xDD44AA],
                    [0x00FFCC, 0x0044dd],
                    [0xFF0000, 0xFF0000]];

//Store the Alpha Values in the form of an array
var alphas:Array = [ 1, 1 ];
//Array of color distribution ratios.
//The value defines percentage of the width where the color is sampled at 100%
var ratios:Array = [ 0, 155 ];
//Create a Matrix instance and assign the Gradient Box
var matr:Matrix = new Matrix();
    matr.createGradientBox(205,155,1.57079632);
//SpreadMethod will define how the gradient is spread. Note!!! Flash uses CONSTANTS to represent String literals
var sprMethod:String = SpreadMethod.PAD;


function drawBack():void
{
    shBack.graphics.beginFill(0x000000);
    shBack.graphics.drawRect(-160,-160,320,320);
    shBack.graphics.endFill();
}

setVertices();
setFaces();
rotateObj(0,0,0);

function setVertices():void
{
    vertsVec[0] = new Vector3D(-objRad,-objRad,-objRad);
    vertsVec[1] = new Vector3D(objRad,-objRad,-objRad);
    vertsVec[2] = new Vector3D(objRad,-objRad,objRad);
    vertsVec[3] = new Vector3D(-objRad,-objRad,objRad);
    vertsVec[4] = new Vector3D(-objRad,objRad,-objRad);
    vertsVec[5] = new Vector3D(objRad,objRad,-objRad);
    vertsVec[6] = new Vector3D(objRad,objRad,objRad);
    vertsVec[7] = new Vector3D(-objRad,objRad,objRad);
}

function setFaces():void
{
    facesVec[0] = [0,4,5,1];
    facesVec[1] = [1,5,6,2];
    facesVec[2] = [2,6,7,3];
    facesVec[3] = [3,7,4,0];
    facesVec[4] = [4,5,6,7];
    facesVec[5] = [0,1,2,3];
}

function rotateObj(rotx:Number,roty:Number,rotz:Number):void
{
    var i:int;
    var j:int;
    //distArray will be used for sorting faces.
    var distArray:Array = [];
    //dispVec will store vertices of the cube (or other object) projected onto xy-plane.
    var dispVec:Vector.<Point> = new Vector.<Point>();
    //Vertices in 3D, after rotx, roty, rotz rotations are applied,
    //will be stored in the next variable.
    var newVertsVec:Vector.<Vector3D> = new Vector.<Vector3D>();
    //z coordinates of midpoints of faces, zAverage, will be used for sorting faces.
    var zAverage:Number;
    var dist:Number;
    var curFace:int;
    var curFaceLen:int;
    var curObjMat:Matrix3D;

    spObject.transform.matrix3D.appendRotation(rotx,Vector3D.X_AXIS);
    spObject.transform.matrix3D.appendRotation(roty,Vector3D.Y_AXIS);
    spObject.transform.matrix3D.appendRotation(rotz,Vector3D.Z_AXIS);

    curObjMat = spObject.transform.matrix3D.clone();
    spObjImage.graphics.clear();

    for(i = 0;i<numVertices;i++)
    {
        newVertsVec[i] = curObjMat.deltaTransformVector(vertsVec[i]);
    }


    for(i = 0;i<numVertices;i++)
    {
        newVertsVec[i].w = (fLen+newVertsVec[i].z)/fLen;
        newVertsVec[i].project();
    }


    for(i = 0;i<numFaces;i++)
    {
        //In our case of a cube, the length of each face is 4
        //but for other objects it may be different.
        curFaceLen = facesVec[i].length;
        zAverage = 0;
        for(j = 0;j<curFaceLen;j++)
        {
            zAverage += newVertsVec[facesVec[i][j]].z;
        }
        zAverage /= curFaceLen;
        dist = zAverage;
        distArray[i] = [dist,i];
    }

    distArray.sort(byDist);

    for(i = 0;i<numVertices;i++)
    {
        dispVec[i] = new Point();
        dispVec[i].x = newVertsVec[i].x;
        dispVec[i].y = newVertsVec[i].y;
    }

    for(i = 0;i<numFaces;i++)
    {
        spObjImage.graphics.lineStyle(1,0xCC0000);
        curFace = distArray[i][1];
        curFaceLen = facesVec[curFace].length;

        //spObjImage.graphics.beginGradientFill( fType, colors[curFace], alphas, ratios, matr, sprMethod );

        //!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
        //comment line below and uncoment one above to get each
        //side of cube with different colors of gradient
        spObjImage.graphics.beginGradientFill( fType, colors[4], alphas, ratios, matr, sprMethod );



        spObjImage.graphics.moveTo(dispVec[facesVec[curFace][0]].x,dispVec[facesVec[curFace][0]].y);
        for(j = 1;j<curFaceLen;j++)
        {
            spObjImage.graphics.lineTo(dispVec[facesVec[curFace][j]].x,dispVec[facesVec[curFace][j]].y);
        }
        spObjImage.graphics.lineTo(dispVec[facesVec[curFace][0]].x,dispVec[facesVec[curFace][0]].y);
        spObjImage.graphics.endFill();
    }
}


function byDist(v:Array,w:Array):Number
{
    if (v[0]>w[0])
    {
        return -1;
    }
    else if (v[0]<w[0])
    {
        return 1;
    }
    else
    {
        return 0;
    }
}


function resetObj():void
{
    spObject.transform.matrix3D = new Matrix3D();
    rotateObj(0,0,0);
}

//Listeners attached to spBoard are resposible for rotating with the mouse.

spBoard.addEventListener(MouseEvent.ROLL_OUT,boardOut);
spBoard.addEventListener(MouseEvent.MOUSE_MOVE,boardMove);
spBoard.addEventListener(MouseEvent.MOUSE_DOWN,boardDown);
spBoard.addEventListener(MouseEvent.MOUSE_UP,boardUp);

function boardOut(e:MouseEvent):void
{
    doRotate = false;
}
function boardDown(e:MouseEvent):void
{
    prevX = spBoard.mouseX;

    prevY = spBoard.mouseY;
    doRotate = true;
}

function boardUp(e:MouseEvent):void
{
    doRotate = false;
}


function boardMove(e:MouseEvent):void
{
    var locX:Number = prevX;
    var locY:Number = prevY;
    if(doRotate)
    {
        prevX = spBoard.mouseX;
        prevY = spBoard.mouseY;
        rotateObj(prevY-locY,-(prevX-locX),0);
        e.updateAfterEvent();
    }
}



//The code below is responsible for sliders' functionality.
var prevXVal:Number = 0;
var prevYVal:Number = 0;
var prevZVal:Number = 0;

xSlider.addEventListener(SliderEvent.CHANGE,xSliderChange);
function xSliderChange(e:SliderEvent):void
{
    var curXVal:Number = e.target.value;
    rotateObj(curXVal-prevXVal,0,0);
    prevXVal = curXVal;
}

ySlider.addEventListener(SliderEvent.CHANGE,ySliderChange);
function ySliderChange(e:SliderEvent):void
{
    var curYVal:Number = e.target.value;
    rotateObj(0,curYVal-prevYVal,0);
    prevYVal = curYVal;
}

zSlider.addEventListener(SliderEvent.CHANGE,zSliderChange);
function zSliderChange(e:SliderEvent):void
{
    var curZVal:Number = e.target.value;
    rotateObj(0,0,curZVal-prevZVal);
    prevZVal = curZVal;
}

perspSlider.addEventListener(SliderEvent.CHANGE,perspSliderChange);
function perspSliderChange(e:SliderEvent):void
{
    fLen = e.target.value;
    rotateObj(0,0,0);
}

//RESET button resets the cube, the sliders and all the variables to their intial values.
btnReset.addEventListener(MouseEvent.CLICK, resetAll);
function resetAll(e:MouseEvent):void
{
    fLen = 500;
    resetObj();
    prevXVal = 0;
    prevYVal = 0;
    prevZVal = 0;
    xSlider.value = 0;
    ySlider.value = 0;
    zSlider.value = 0;
    perspSlider.value = fLen;
}