public static void ZeroNormals(VertexPositionNormalColor[] vertices)
{
for (var i = 0; i < vertices.Length; i++)
{
vertices[i].Normal = Vector3.Zero;
}
}
public SimpleSurface(VertexPositionNormalColor[] vertices, int xDimension, int yDimension)
{
_xDimension = xDimension;
_yDimension = yDimension;
_vertices = vertices;
if (GraphicsDeviceManager.Current.RenderMode != RenderMode.Hardware) return;
_vertexBuffer = new VertexBuffer(GraphicsDeviceManager.Current.GraphicsDevice,
typeof (VertexPositionNormalColor), vertices.Length, BufferUsage.WriteOnly);
_vertexBuffer.SetData(_vertices);
DrawStyle = DrawStyle.Surface;
}
/// <summary>
/// Calculate lighing normals for specified vertex array.
/// </summary>
/// <param name="vertices"></param>
/// <param name="indices"></param>
public static void CalculateTriangleNormals(VertexPositionNormalColor[] vertices, short[] indices)
{
ZeroNormals(vertices);
for (var i = 0; i < indices.Length/3; i++)
{
var idx0 = indices[i*3];
var idx1 = indices[i*3 + 1];
var idx2 = indices[i*3 + 2];
var side0 = vertices[idx0].Position - vertices[idx2].Position;
var side1 = vertices[idx0].Position - vertices[idx1].Position;
var normal = Vector3.Cross(side0, side1);
vertices[idx0].Normal -= normal;
vertices[idx1].Normal -= normal;
vertices[idx2].Normal -= normal;
}
}
private ISurface CreateSegment(int uIdx, int vIdx,
MathFunction function)
{
var meshDensity = Properties.MeshDensity;
var uSize = Math.Abs(UDimension.Max - UDimension.Min)
/(UDimension.KnotCount - 1);
var vSize = Math.Abs(VDimension.Max - VDimension.Min)
/(VDimension.KnotCount - 1);
var u0 = UDimension.Min + uSize*uIdx; //afv[uIdx][vIdx].X;
var u1 = UDimension.Min + uSize*(uIdx + 1);
var v0 = VDimension.Min + vSize*vIdx;
var v1 = VDimension.Min + vSize*(vIdx + 1);
var uKnotsDistance = Math.Abs(u1 - u0);
var xCount = Math.Ceiling(uKnotsDistance/meshDensity);
var yKnotDistance = Math.Abs(v1 - v0);
var yCount = Math.Ceiling(yKnotDistance/meshDensity);
var verticesCount = (int) ((++xCount)*(++yCount));
var segmentMeshVertices =
new VertexPositionNormalColor[verticesCount];
var k = 0;
var x = (float) u0;
for (var i = 0; i < xCount; i++, x += meshDensity)
{
x = x < u1 ? x : (float) u1;
var y = (float) v0;
for (var j = 0; j < yCount; j++, y += meshDensity)
{
y = y < v1 ? y : (float) v1;
var z = (float) function.SafeCall(x, y);
segmentMeshVertices[k++] =
new VertexPositionNormalColor(new Vector3(x, y, z),
DefaultNormal,
DefaultColor);
}
}
return new SimpleSurface(segmentMeshVertices, (int) xCount,
(int) yCount);
}
using System;
using System.Collections.Generic;
using HermiteInterpolation.MathFunctions;
using HermiteInterpolation.Numerics;
using HermiteInterpolation.Primitives;
using HermiteInterpolation.SplineKnots;
using MathNet.Numerics.LinearAlgebra;
using Microsoft.Xna.Framework;
namespace HermiteInterpolation.Shapes.SplineInterpolation
{
public class BicubicHermiteSurface :Spline
{
public BicubicHermiteSurface(SurfaceDimension uDimension, SurfaceDimension vDimension, MathExpression mathExpression, Derivation derivation = Derivation.Zero) : base(uDimension, vDimension, mathExpression, derivation)
{
}
public BicubicHermiteSurface(SurfaceDimension uDimension, SurfaceDimension vDimension, InterpolativeMathFunction interpolativeMathFunction, Derivation derivation = Derivation.Zero) : base(uDimension, vDimension, interpolativeMathFunction, derivation)
{
}
public BicubicHermiteSurface(SurfaceDimension uDimension, SurfaceDimension vDimension, KnotsGenerator knotsGenerator, Derivation derivation = Derivation.Zero) : base(uDimension, vDimension, knotsGenerator, derivation)
{
}
protected delegate Vector<double> BasisVector(double t, double t0, double t1);
/// <summary>
///
/// </summary>
/// <param name="uIdx"></param>
/// <param name="vIdx"></param>
/// <param name="knots"></param>
/// <returns></returns>
protected override ISurface CreateSegment(int uIdx, int vIdx, KnotMatrix knots)
{
var u0 = knots[uIdx,vIdx].X;
var u1 = knots[uIdx+1,vIdx].X;
var v0 = knots[uIdx,vIdx].Y;
var v1 = knots[uIdx,vIdx+1].Y;
var meshDensity = Constants.MeshDensity;
var uKnotsDistance = Math.Abs(u1-u0);
var xCount = Math.Ceiling(uKnotsDistance/meshDensity);
var yKnotDistance = Math.Abs(v1 - v0);
var yCount = Math.Ceiling(yKnotDistance / meshDensity);
var verticesCount = (int)((++xCount) * (++yCount));
var segmentMeshVertices = new VertexPositionNormalColor[verticesCount];
var basisCalculator = new BicubicBasis(knots,Derivation);//BasisFactory.CreateBasis(Surface.Type);
var phi = basisCalculator.Matrix(uIdx, vIdx);
var k = 0;
var x = (float) u0 ;
for (var i = 0; i < xCount; i++,x += meshDensity)
{
x = x < u1 ? x : (float)u1;
var lambda1 = basisCalculator.Vector(x, u0, u1);
var basis = phi.LeftMultiply(lambda1);
var y = (float) v0;
for (var j = 0; j < yCount; j++,y += meshDensity)
{
y = y < v1 ? y : (float)v1;
var lambda2 = basisCalculator.Vector(y, v0, v1);
var zv = basis.PointwiseMultiply(lambda2);
var z = (float) zv.Sum();
z = MathHelper.Clamp(z, -Constants.MaxSceneZDifference, Constants.MaxSceneZDifference);
segmentMeshVertices[k++] = new VertexPositionNormalColor(new Vector3(x, y, z), DefaultNormal,
DefaultColor);
}
}
return new SimpleSurface(segmentMeshVertices, (int)xCount, (int)yCount);
}
}
}
