private static readonly PointD3D _NormalVectorPZX = new PointD3D(0, 1, 0); // 正方体表面的 +ZX 法向量。
//
/// <summary>
/// 绘制一个长方体，并返回表示是否已经实际完成绘图的布尔值。
/// </summary>
/// <param name="bmp">用于绘制的位图。</param>
/// <param name="center">长方体的中心坐标。</param>
/// <param name="size">长方体的大小。</param>
/// <param name="color">长方体的颜色。</param>
/// <param name="edgeWidth">长方体的棱的宽度。</param>
/// <param name="affineMatrices">仿射矩阵（左矩阵）列表。</param>
/// <param name="focalLength">焦距。</param>
/// <param name="illuminationDirection">光照方向。</param>
/// <param name="illuminationDirectionIsAfterAffineTransform">光照方向是否基于仿射变换之后的坐标系。</param>
/// <param name="exposure">曝光，取值范围为 [-100, 100]。</param>
/// <param name="antiAlias">是否使用抗锯齿模式绘图。</param>
/// <returns>布尔值，表示是否已经实际完成绘图。</returns>
public static bool PaintCuboid(Bitmap bmp, PointD3D center, PointD3D size, Color color, float edgeWidth, List <Matrix> affineMatrices, double focalLength, PointD3D illuminationDirection, bool illuminationDirectionIsAfterAffineTransform, double exposure, bool antiAlias)
{
try
{
if (bmp is null || center.IsNaNOrInfinity || (size.IsNaNOrInfinity || size.IsZero) || (color.IsEmpty || color.A == 0) || InternalMethod.IsNaNOrInfinity(edgeWidth) || InternalMethod.IsNullOrEmpty(affineMatrices) || (InternalMethod.IsNaNOrInfinity(focalLength) || focalLength < 0) || illuminationDirection.IsNaNOrInfinity || InternalMethod.IsNaNOrInfinity(exposure))
{
return(false);
}
else
{
PointD3D P3D_000 = _Vertex000;
PointD3D P3D_100 = _Vertex100;
PointD3D P3D_010 = _Vertex010;
PointD3D P3D_110 = _Vertex110;
PointD3D P3D_001 = _Vertex001;
PointD3D P3D_101 = _Vertex101;
PointD3D P3D_011 = _Vertex011;
PointD3D P3D_111 = _Vertex111;
P3D_000.Scale(size);
P3D_100.Scale(size);
P3D_010.Scale(size);
P3D_110.Scale(size);
P3D_001.Scale(size);
P3D_101.Scale(size);
P3D_011.Scale(size);
P3D_111.Scale(size);
P3D_000.Offset(center);
P3D_100.Offset(center);
P3D_010.Offset(center);
P3D_110.Offset(center);
P3D_001.Offset(center);
P3D_101.Offset(center);
P3D_011.Offset(center);
P3D_111.Offset(center);
P3D_000.AffineTransform(affineMatrices);
P3D_100.AffineTransform(affineMatrices);
P3D_010.AffineTransform(affineMatrices);
P3D_110.AffineTransform(affineMatrices);
P3D_001.AffineTransform(affineMatrices);
P3D_101.AffineTransform(affineMatrices);
P3D_011.AffineTransform(affineMatrices);
P3D_111.AffineTransform(affineMatrices);
PointD3D PrjCenter = new PointD3D(bmp.Width / 2, bmp.Height / 2, 0);
PointD P2D_000 = P3D_000.ProjectToXY(PrjCenter, focalLength);
PointD P2D_100 = P3D_100.ProjectToXY(PrjCenter, focalLength);
PointD P2D_010 = P3D_010.ProjectToXY(PrjCenter, focalLength);
PointD P2D_110 = P3D_110.ProjectToXY(PrjCenter, focalLength);
PointD P2D_001 = P3D_001.ProjectToXY(PrjCenter, focalLength);
PointD P2D_101 = P3D_101.ProjectToXY(PrjCenter, focalLength);
PointD P2D_011 = P3D_011.ProjectToXY(PrjCenter, focalLength);
PointD P2D_111 = P3D_111.ProjectToXY(PrjCenter, focalLength);
PointF P_000 = P2D_000.ToPointF();
PointF P_100 = P2D_100.ToPointF();
PointF P_010 = P2D_010.ToPointF();
PointF P_110 = P2D_110.ToPointF();
PointF P_001 = P2D_001.ToPointF();
PointF P_101 = P2D_101.ToPointF();
PointF P_011 = P2D_011.ToPointF();
PointF P_111 = P2D_111.ToPointF();
PointD3D[][] Element3D = new PointD3D[][]
{
// XY 面
new PointD3D[] { P3D_000, P3D_010, P3D_110, P3D_100 },
new PointD3D[] { P3D_001, P3D_011, P3D_111, P3D_101 },
// YZ 面
new PointD3D[] { P3D_000, P3D_001, P3D_011, P3D_010 },
new PointD3D[] { P3D_100, P3D_101, P3D_111, P3D_110 },
// ZX 面
new PointD3D[] { P3D_000, P3D_001, P3D_101, P3D_100 },
new PointD3D[] { P3D_010, P3D_011, P3D_111, P3D_110 },
// X 棱
new PointD3D[] { P3D_000, P3D_100 },
new PointD3D[] { P3D_010, P3D_110 },
new PointD3D[] { P3D_001, P3D_101 },
new PointD3D[] { P3D_011, P3D_111 },
// Y 棱
new PointD3D[] { P3D_000, P3D_010 },
new PointD3D[] { P3D_100, P3D_110 },
new PointD3D[] { P3D_001, P3D_011 },
new PointD3D[] { P3D_101, P3D_111 },
// Z 棱
new PointD3D[] { P3D_000, P3D_001 },
new PointD3D[] { P3D_100, P3D_101 },
new PointD3D[] { P3D_010, P3D_011 },
new PointD3D[] { P3D_110, P3D_111 }
};
PointF[][] Element2D = new PointF[][]
{
// XY 面
new PointF[] { P_000, P_010, P_110, P_100 },
new PointF[] { P_001, P_011, P_111, P_101 },
// YZ 面
new PointF[] { P_000, P_001, P_011, P_010 },
new PointF[] { P_100, P_101, P_111, P_110 },
// ZX 面
new PointF[] { P_000, P_001, P_101, P_100 },
new PointF[] { P_010, P_011, P_111, P_110 },
// X 棱
new PointF[] { P_000, P_100 },
new PointF[] { P_010, P_110 },
new PointF[] { P_001, P_101 },
new PointF[] { P_011, P_111 },
// Y 棱
new PointF[] { P_000, P_010 },
new PointF[] { P_100, P_110 },
new PointF[] { P_001, P_011 },
new PointF[] { P_101, P_111 },
// Z 棱
new PointF[] { P_000, P_001 },
new PointF[] { P_100, P_101 },
new PointF[] { P_010, P_011 },
new PointF[] { P_110, P_111 }
};
//
bool CuboidIsVisible = false;
bool[] ElementVisible = new bool[Element2D.Length];
for (int i = 0; i < Element2D.Length; i++)
{
bool EVisible = false;
foreach (PointF P in Element2D[i])
{
PointD P2D = P;
if (P2D.IsNaNOrInfinity)
{
EVisible = false;
break;
}
else
{
if (Geometry.PointIsVisibleInRectangle(P2D, new RectangleF(new Point(0, 0), bmp.Size)))
{
EVisible = true;
}
}
}
ElementVisible[i] = EVisible;
if (!CuboidIsVisible && EVisible)
{
CuboidIsVisible = true;
}
}
if (!CuboidIsVisible)
{
return(false);
}
else
{
double[] IlluminationIntensity = new double[Element3D.Length];
double Exposure = Math.Max(-2, Math.Min(exposure / 50, 2));
if (illuminationDirection.IsZero)
{
for (int i = 0; i < 6; i++)
{
IlluminationIntensity[i] = Exposure;
}
for (int i = 6; i < Element3D.Length; i++)
{
IlluminationIntensity[i] = Constant.HalfSqrt2 * (Exposure + 1) + (Exposure - 1);
}
}
else
{
PointD3D[] NormalVector = new PointD3D[]
{
// XY 面
_NormalVectorNXY,
_NormalVectorPXY,
// YZ 面
_NormalVectorNYZ,
_NormalVectorPYZ,
// ZX 面
_NormalVectorNZX,
_NormalVectorPZX
};
if (illuminationDirectionIsAfterAffineTransform)
{
PointD3D NewOriginOpposite = PointD3D.Zero.AffineTransformCopy(affineMatrices).Opposite;
for (int i = 0; i < NormalVector.Length; i++)
{
NormalVector[i].AffineTransform(affineMatrices);
NormalVector[i].Offset(NewOriginOpposite);
}
}
double[] Angle = new double[NormalVector.Length];
for (int i = 0; i < NormalVector.Length; i++)
{
Angle[i] = illuminationDirection.AngleFrom(NormalVector[i]);
}
for (int i = 0; i < Angle.Length; i++)
{
double A = Angle[i];
double CosA = Math.Cos(A);
double CosSqrA = CosA * CosA;
double _IlluminationIntensity = (A < Constant.HalfPi ? -CosSqrA : (A > Constant.HalfPi ? CosSqrA : 0));
if (color.A < 255 && A != Constant.HalfPi)
{
double Transmittance = 1 - (double)color.A / 255;
if (A < Constant.HalfPi)
{
_IlluminationIntensity += (Transmittance * Math.Abs(CosA) * CosSqrA);
}
else
{
_IlluminationIntensity -= ((1 - Transmittance) * (1 - Math.Abs(CosA)) * CosSqrA);
}
}
_IlluminationIntensity += Exposure;
IlluminationIntensity[i] = _IlluminationIntensity;
}
for (int i = 6; i < Element3D.Length; i++)
{
double _IlluminationIntensity = 0;
int Num = 0;
for (int j = 0; j < 6; j++)
{
bool Flag = true;
foreach (PointD3D P in Element3D[i])
{
if (!Element3D[j].Contains(P))
{
Flag = false;
break;
}
}
if (Flag)
{
_IlluminationIntensity += IlluminationIntensity[j];
Num++;
}
}
_IlluminationIntensity = Constant.HalfSqrt2 * (_IlluminationIntensity / Num + 1) + (Exposure - 1);
IlluminationIntensity[i] = _IlluminationIntensity;
}
}
for (int i = 0; i < IlluminationIntensity.Length; i++)
{
IlluminationIntensity[i] = Math.Max(-1, Math.Min(IlluminationIntensity[i], 1));
}
//
Color[] ElementColor = new Color[IlluminationIntensity.Length];
for (int i = 0; i < IlluminationIntensity.Length; i++)
{
double _IlluminationIntensity = IlluminationIntensity[i];
if (_IlluminationIntensity == 0)
{
ElementColor[i] = color;
}
else
{
ColorX EColor = color;
if (_IlluminationIntensity < 0)
{
EColor.Lightness_HSL += EColor.Lightness_HSL * _IlluminationIntensity;
}
else
{
EColor.Lightness_HSL += (100 - EColor.Lightness_HSL) * _IlluminationIntensity;
}
ElementColor[i] = EColor.ToColor();
}
}
//
double[] ElementZAvg = new double[Element3D.Length];
for (int i = 0; i < Element3D.Length; i++)
{
PointD3D[] Element = Element3D[i];
double ZAvg = 0;
foreach (PointD3D P in Element)
{
ZAvg += P.Z;
}
ZAvg /= Element.Length;
ElementZAvg[i] = ZAvg;
}
int[] ElementIndex = new int[ElementZAvg.Length];
for (int i = 0; i < ElementZAvg.Length; i++)
{
ElementIndex[i] = i;
}
for (int i = 0; i < ElementZAvg.Length; i++)
{
for (int j = i + 1; j < ElementZAvg.Length; j++)
{
if (ElementZAvg[ElementIndex[i]] < ElementZAvg[ElementIndex[j]] || (ElementZAvg[ElementIndex[i]] <= ElementZAvg[ElementIndex[j]] + edgeWidth && Element2D[ElementIndex[i]].Length < Element2D[ElementIndex[j]].Length))
{
int Temp = ElementIndex[i];
ElementIndex[i] = ElementIndex[j];
ElementIndex[j] = Temp;
}
}
}
//
using (Graphics Grph = Graphics.FromImage(bmp))
{
if (antiAlias)
{
Grph.SmoothingMode = SmoothingMode.AntiAlias;
}
//
for (int i = 0; i < ElementIndex.Length; i++)
{
int EIndex = ElementIndex[i];
if (ElementVisible[EIndex])
{
Color EColor = ElementColor[EIndex];
if (!EColor.IsEmpty && EColor.A > 0)
{
PointF[] Element = Element2D[EIndex];
if (Element.Length >= 3)
{
try
{
using (SolidBrush Br = new SolidBrush(EColor))
{
Grph.FillPolygon(Br, Element);
}
}
catch { }
}
else if (Element.Length == 2)
{
if (edgeWidth > 0)
{
float EdgeWidth = (focalLength == 0 ? edgeWidth : (float)(focalLength / (ElementZAvg[EIndex] - PrjCenter.Z) * edgeWidth));
try
{
Brush Br;
Func <Color, double, int> GetAlpha = (Cr, Z) =>
{
int Alpha;
if (focalLength == 0)
{
Alpha = Cr.A;
}
else
{
if (Z - PrjCenter.Z <= focalLength)
{
Alpha = Cr.A;
}
else
{
Alpha = (int)Math.Max(0, Math.Min(focalLength / (Z - PrjCenter.Z) * Cr.A, 255));
}
}
if (EdgeWidth < 1)
{
Alpha = (int)(Alpha * EdgeWidth);
}
return(Alpha);
};
if (((PointD)Element[0]).DistanceFrom(Element[1]) > 1)
{
int Alpha0 = GetAlpha(EColor, Element3D[EIndex][0].Z), Alpha1 = GetAlpha(EColor, Element3D[EIndex][1].Z);
Br = new LinearGradientBrush(Element[0], Element[1], Color.FromArgb(Alpha0, EColor), Color.FromArgb(Alpha1, EColor));
}
else
{
int Alpha = GetAlpha(EColor, ElementZAvg[EIndex]);
Br = new SolidBrush(Color.FromArgb(Alpha, EColor));
}
using (Pen Pn = new Pen(Br, EdgeWidth))
{
Grph.DrawLines(Pn, Element);
}
if (!(Br is null))
{
Br.Dispose();
}
}
catch { }
}
}
}
}
}
}
//
return(true);
}
}
}
