Papervision 3D Controlling Top and Bottom Cylinder Materials at Papervision 3D Tutorials

custom-materials-cylinder
While working on a project this morning I came across the need to have a different material applied to a primitive cylinder. After digging through the Cylinder source code I came across these lines

PLAIN TEXT

Actionscript:

if (fBottomFace) aFace.push( new Triangle3D(this, [aP1, aP3, aP2], matInstance, [aP1uv, aP3uv, aP2uv]) );
//and
if (fTopFace) aFace.push( new Triangle3D(this, [aP1, aP2, aP3], matInstance, [aP1uv, aP2uv, aP3uv]));

Since matInstance is just a material it can easily be replaced. I was in a hurry so I decided to just directly modified the class; not the greatest idea but it worked.

PLAIN TEXT

Actionscript:

if (j == 0) {
if(bottomMat)
{
if (fBottomFace) aFace.push( new Triangle3D(this, [aP1, aP3, aP2], bottomMat, [aP1uv, aP3uv, aP2uv]) );
}
else
{
if (fBottomFace) aFace.push( new Triangle3D(this, [aP1, aP3, aP2], matInstance, [aP1uv, aP3uv, aP2uv]) );
}
}
else
{
if(topMat)
{
if (fTopFace) aFace.push( new Triangle3D(this, [aP1, aP2, aP3], topMat, [aP1uv, aP2uv, aP3uv]));
}
else
{
if (fTopFace) aFace.push( new Triangle3D(this, [aP1, aP2, aP3], matInstance, [aP1uv, aP2uv, aP3uv]));
}
}

Here is the new way to create the Cylinder:

PLAIN TEXT

Actionscript:

var cyl:Cylinder = new Cylinder(new ColorMaterial(0x000000),200,900,5,20,200,true,true,new ColorMaterial(0x8ad51f),new ColorMaterial(0x00FF00));

Here is the full modified Papervision Cylinder.as class:

PLAIN TEXT

Actionscript:

package org.papervision3d.objects.primitives {
import org.papervision3d.Papervision3D;
import org.papervision3d.core.geom.*;
import org.papervision3d.core.geom.renderables.Triangle3D;
import org.papervision3d.core.geom.renderables.Vertex3D;
import org.papervision3d.core.math.NumberUV;
import org.papervision3d.core.proto.*;
/**
* The Cylinder class lets you create and display Cylinders.
*
* The Cylinder is divided in vertical and horizontal segment, the smallest combination is two vertical and three horizontal segments.
*/
public class Cylinder extends TriangleMesh3D
{
/**
* Number of segments horizontally. Defaults to 8.
*/
public var segmentsW :Number;
/**
* Number of segments vertically. Defaults to 6.
*/
public var segmentsH :Number;
/**
* Default radius of Cylinder if not defined.
*/
static public const DEFAULT_RADIUS :Number = 100;
/**
* Default height if not defined.
*/
static public const DEFAULT_HEIGHT :Number = 100;
/**
* Default scale of Cylinder texture if not defined.
*/
static public const DEFAULT_SCALE :Number = 1;
/**
* Default value of gridX if not defined.
*/
static public const DEFAULT_SEGMENTSW :Number = 8;
/**
* Default value of gridY if not defined.
*/
static public const DEFAULT_SEGMENTSH :Number = 6;
/**
* Minimum value of gridX.
*/
static public const MIN_SEGMENTSW :Number = 3;
/**
* Minimum value of gridY.
*/
static public const MIN_SEGMENTSH :Number = 1;
public var topFace
// ___________________________________________________________________________________________________
// N E W
// NN NN EEEEEE WW WW
// NNN NN EE WW WW WW
// NNNNNN EEEE WWWWWWWW
// NN NNN EE WWW WWW
// NN NN EEEEEE WW WW
/**
* Create a new Cylinder object.
*
* @param material A MaterialObject3D object that contains the material properties of the object.
*
* @param radius [optional] - Desired radius.
*
* @param segmentsW [optional] - Number of segments horizontally. Defaults to 8.
*
* @param segmentsH [optional] - Number of segments vertically. Defaults to 6.
*
* @param topRadius [optional] - An optional parameter for con- or diverging cylinders.
*
* @param topFace [optional] - An optional parameter specifying if the top face of the cylinder should be drawn.
*
* @param bottomFace [optional] - An optional parameter specifying if the bottom face of the cylinder should be drawn.
*
*/
public function Cylinder( material:MaterialObject3D=null, radius:Number=100, height:Number=100, segmentsW:int=8, segmentsH:int=6, topRadius:Number=-1, topFace:Boolean=true, bottomFace:Boolean=true,topMat:MaterialObject3D = null ,bottomMat:MaterialObject3D = null)
{
super( material, new Array(), new Array(), null );
this.segmentsW = Math.max( MIN_SEGMENTSW, segmentsW || DEFAULT_SEGMENTSW); // Defaults to 8
this.segmentsH = Math.max( MIN_SEGMENTSH, segmentsH || DEFAULT_SEGMENTSH); // Defaults to 6
if (radius==0) radius = DEFAULT_RADIUS; // Defaults to 100
if (height==0) height = DEFAULT_HEIGHT; // Defaults to 100
if (topRadius==-1) topRadius = radius;
var scale :Number = DEFAULT_SCALE;
buildCylinder( radius, height, topRadius, topFace, bottomFace,topMat,bottomMat );
}
private function buildCylinder( fRadius:Number, fHeight:Number, fTopRadius:Number, fTopFace:Boolean, fBottomFace:Boolean ,topMat:MaterialObject3D,bottomMat:MaterialObject3D):void
{
var matInstance:MaterialObject3D = material;
var i:Number, j:Number, k:Number;
var iHor:Number = Math.max(MIN_SEGMENTSW, this.segmentsW);
var iVer:Number = Math.max(MIN_SEGMENTSH, this.segmentsH);
var aVertice:Array = this.geometry.vertices;
var aFace:Array = this.geometry.faces;
var aVtc:Array = new Array();
for (j=0;j<(iVer+1);j++) { // vertical
var fRad1:Number = Number(j/iVer);
var fZ:Number = fHeight*(j/(iVer+0))-fHeight/2;//-fRadius*Math.cos(fRad1*Math.PI);
var fRds:Number = fTopRadius+(fRadius-fTopRadius)*(1-j/(iVer));//*Math.sin(fRad1*Math.PI);
var aRow:Array = new Array();
var oVtx:Vertex3D;
for (i=0;i<iHor;i++) { // horizontal
var fRad2:Number = Number(2*i/iHor);
var fX:Number = fRds*Math.sin(fRad2*Math.PI);
var fY:Number = fRds*Math.cos(fRad2*Math.PI);
//if (!((j==0||j==iVer)&&i>0)) { // top||bottom = 1 vertex
oVtx = new Vertex3D(fY,fZ,fX);
aVertice.push(oVtx);
//}
aRow.push(oVtx);
}
aVtc.push(aRow);
}
var iVerNum:int = aVtc.length;
var aP4uv:NumberUV, aP1uv:NumberUV, aP2uv:NumberUV, aP3uv:NumberUV;
var aP1:Vertex3D, aP2:Vertex3D, aP3:Vertex3D, aP4:Vertex3D;
for (j=0;j<iVerNum;j++) {
var iHorNum:int = aVtc[j].length;
for (i=0;i<iHorNum;i++) {
if (j>0&&i>=0) {
// select vertices
var bEnd:Boolean = i==(iHorNum-0);
aP1 = aVtc[j][bEnd?0:i];
aP2 = aVtc[j][(i==0?iHorNum:i)-1];
aP3 = aVtc[j-1][(i==0?iHorNum:i)-1];
aP4 = aVtc[j-1][bEnd?0:i];
// uv
var fJ0:Number = j / iVerNum;
var fJ1:Number = (j-1) / iVerNum;
var fI0:Number = (i+1) / iHorNum;
var fI1:Number = i / iHorNum;
aP4uv = new NumberUV(fI0,fJ1);
aP1uv = new NumberUV(fI0,fJ0);
aP2uv = new NumberUV(fI1,fJ0);
aP3uv = new NumberUV(fI1,fJ1);
// 2 faces
aFace.push( new Triangle3D(this, [aP1,aP2,aP3], matInstance, [aP1uv,aP2uv,aP3uv]) );
aFace.push( new Triangle3D(this, [aP1,aP3,aP4], matInstance, [aP1uv,aP3uv,aP4uv]) );
}
}
if (j==0||j==(iVerNum-1)) {
for (i=0;i<(iHorNum-2);i++) {
// uv
var iI:int = Math.floor(i/2);
aP1 = aVtc[j][iI];
aP2 = (i%2==0)? (aVtc[j][iHorNum-2-iI]) : (aVtc[j][iI+1]);
aP3 = (i%2==0)? (aVtc[j][iHorNum-1-iI]) : (aVtc[j][iHorNum-2-iI]);
var bTop:Boolean = j==0;
aP1uv = new NumberUV( (bTop?1:0)+(bTop?-1:1)*(aP1.x/fRadius/2+.5), aP1.z/fRadius/2+.5 );
aP2uv = new NumberUV( (bTop?1:0)+(bTop?-1:1)*(aP2.x/fRadius/2+.5), aP2.z/fRadius/2+.5 );
aP3uv = new NumberUV( (bTop?1:0)+(bTop?-1:1)*(aP3.x/fRadius/2+.5), aP3.z/fRadius/2+.5 );
// face
if (j == 0) {
if(bottomMat)
{
if (fBottomFace) aFace.push( new Triangle3D(this, [aP1, aP3, aP2], bottomMat, [aP1uv, aP3uv, aP2uv]) );
}
else
{
if (fBottomFace) aFace.push( new Triangle3D(this, [aP1, aP3, aP2], matInstance, [aP1uv, aP3uv, aP2uv]) );
}
}
else {
if(topMat)
{
if (fTopFace) aFace.push( new Triangle3D(this, [aP1, aP2, aP3], topMat, [aP1uv, aP2uv, aP3uv]));
}
else
{
if (fTopFace) aFace.push( new Triangle3D(this, [aP1, aP2, aP3], matInstance, [aP1uv, aP2uv, aP3uv]));
}
}
}
}
}
this.geometry.ready = true;
if(Papervision3D.useRIGHTHANDED)
this.geometry.flipFaces();
}
}
}