// Matrix.java

public class Matrix {
   public Matrix ()  {}

   public final float determinant ()
   {  return (m11 * m22 * m33 + m21 * m32 * m13 + m31 * m12 * m23) -
              m31 * m22 * m13 - m21 * m12 * m33 - m11 * m32 * m23;
   }

   public final void identity ()
   {  m11 = 1F;   m12 = 0F;   m13 = 0F;   m14 = 0F;
      m21 = 0F;   m22 = 1F;   m23 = 0F;   m24 = 0F;
      m31 = 0F;   m32 = 0F;   m33 = 1F;   m34 = 0F;
      m41 = 0F;   m42 = 0F;   m43 = 0F;   m44 = 1F;
   }

   public final void inverse (Matrix matrix)
   { float f = 1.0F / determinant ();
      matrix.m11 = (m22 * m33 - m32 * m23) * f;
      matrix.m12 = (m32 * m13 - m12 * m33) * f;
      matrix.m13 = (m12 * m23 - m22 * m13) * f;
      matrix.m21 = (m23 * m31 - m33 * m21) * f;
      matrix.m22 = (m33 * m11 - m13 * m31) * f;
      matrix.m23 = (m13 * m21 - m23 * m11) * f;
      matrix.m31 = (m21 * m32 - m31 * m22) * f;
      matrix.m32 = (m31 * m12 - m11 * m32) * f;
      matrix.m33 = (m11 * m22 - m21 * m12) * f;
      matrix.m14 = -(matrix.m11 * m14 + matrix.m12 * m24 + matrix.m13 * m34);
      matrix.m24 = -(matrix.m21 * m14 + matrix.m22 * m24 + matrix.m23 * m34);
      matrix.m34 = -(matrix.m31 * m14 + matrix.m32 * m24 + matrix.m33 * m34);
      matrix.m41 = m41;
      matrix.m42 = m42;
      matrix.m43 = m43;
      matrix.m44 = m44;
   }

   public final void load (Matrix matrix)
   {  m11 = matrix.m11;  m12 = matrix.m12;  m13 = matrix.m13;  m14 = matrix.m14;
      m21 = matrix.m21;  m22 = matrix.m22;  m23 = matrix.m23;  m24 = matrix.m24;
      m31 = matrix.m31;  m32 = matrix.m32;  m33 = matrix.m33;  m34 = matrix.m34;
      m41 = matrix.m41;  m42 = matrix.m42;  m43 = matrix.m43;  m44 = matrix.m44;
   }

   public final void lookat (Vector vector, Vector vector1, Vector vector2)
   { float f = vector1.x - vector.x;
     float f1 = vector1.y - vector.y;
     float f2 = vector1.z - vector.z;
     float f3 = (float)Math.sqrt (f * f + f1 * f1 + f2 * f2);
      if (f3 == 0.0F) {
         f = 1.0F;
         f1 = 0.0F;
         f2 = 0.0F;
      }
      else {
        float f4 = 1.0F / f3;
         f *= f4;
         f1 *= f4;
         f2 *= f4;
      }
     float f5 = -(f * vector2.x + f * vector2.y + f * vector2.z);
     float f6 = -(f1 * vector2.x + f1 * vector2.y + f1 * vector2.z);
     float f7 = -(f2 * vector2.x + f2 * vector2.y + f2 * vector2.z);
      f3 = (float)Math.sqrt (f5 * f5 + f6 * f6 + f7 * f7);
      if (f3 == 0.0F) {
         f5 = 1.0F;
         f6 = 0.0F;
         f7 = 0.0F;
      }
      else {
        float f8 = 1.0F / f3;
         f5 *= f8;
         f6 *= f8;
         f7 *= f8;
      }
     float f9 = f * f5 + f * f6 + f * f7;
     float f10 = f1 * f5 + f1 * f6 + f1 * f7;
     float f11 = f2 * f5 + f2 * f6 + f2 * f7;
      f3 = (float)Math.sqrt (f9 * f9 + f10 * f10 + f11 * f11);
      if (f3 == 0.0F) {
         f9  = 1.0F;
         f10 = 0.0F;
         f11 = 0.0F;
      }
      else {
        float f12 = 1.0F / f3;
         f9  *= f12;
         f10 *= f12;
         f11 *= f12;
      }
      m11 = f5;    m21 = f6;    m31 = f7;
      m12 = f9;    m22 = f10;   m32 = f11;
      m13 = f;     m23 = f;     m33 = f;
      m14 = 0.0F;  m24 = 0.0F;  m34 = 0.0F;
      m41 = 0.0F;  m42 = 0.0F;  m43 = 0.0F;  m44 = 1.0F;
   }

   public final void multiply (Matrix matrix, Matrix matrix1)
   {  matrix1.m11 = m11 * matrix.m11 + m12 * matrix.m21 + m13 * matrix.m31 +
                    m14 * matrix.m41;
      matrix1.m12 = m11 * matrix.m12 + m12 * matrix.m22 + m13 * matrix.m32 +
                    m14 * matrix.m42;
      matrix1.m13 = m11 * matrix.m13 + m12 * matrix.m23 + m13 * matrix.m33 +
                    m14 * matrix.m43;
      matrix1.m14 = m11 * matrix.m14 + m12 * matrix.m24 + m13 * matrix.m34 +
                    m14 * matrix.m44;
      matrix1.m21 = m21 * matrix.m11 + m22 * matrix.m21 + m23 * matrix.m31 +
                    m24 * matrix.m41;
      matrix1.m22 = m21 * matrix.m12 + m22 * matrix.m22 + m23 * matrix.m32 +
                    m24 * matrix.m42;
      matrix1.m23 = m21 * matrix.m13 + m22 * matrix.m23 + m23 * matrix.m33 +
                    m24 * matrix.m43;
      matrix1.m24 = m21 * matrix.m14 + m22 * matrix.m24 + m23 * matrix.m34 +
                    m24 * matrix.m44;
      matrix1.m31 = m31 * matrix.m11 + m32 * matrix.m21 + m33 * matrix.m31 +
                    m34 * matrix.m41;
      matrix1.m32 = m31 * matrix.m12 + m32 * matrix.m22 + m33 * matrix.m32 +
                    m34 * matrix.m42;
      matrix1.m33 = m31 * matrix.m13 + m32 * matrix.m23 + m33 * matrix.m33 +
                    m34 * matrix.m43;
      matrix1.m34 = m31 * matrix.m14 + m32 * matrix.m24 + m33 * matrix.m34 +
                    m34 * matrix.m44;
      matrix1.m41 = m41 * matrix.m11 + m42 * matrix.m21 + m43 * matrix.m31 +
                    m44 * matrix.m41;
      matrix1.m42 = m41 * matrix.m12 + m42 * matrix.m22 + m43 * matrix.m32 +
                    m44 * matrix.m42;
      matrix1.m43 = m41 * matrix.m13 + m42 * matrix.m23 + m43 * matrix.m33 +
                    m44 * matrix.m43;
      matrix1.m44 = m41 * matrix.m14 + m42 * matrix.m24 + m43 * matrix.m34 +
                    m44 * matrix.m44;
   }

   public final void orthographic (float f, float f1, float f2, float f3,
                                   float f4, float f5)
   { float f6 = 1.0F / (f1 - f);
     float f7 = 1.0F / (f3 - f2);
     float f8 = 1.0F / (f5 - f4);
      m11 = 2.0F * f6;  m12 = 0.0F;       m13 = 0.0F;  m14 = (f1 + f) * f6;
      m21 = 0.0F;       m22 = 2.0F * f7;  m23 = 0.0F;  m24 = (f3 + f2) * f7;
      m31 = 0.0F;       m32 = 0.0F;       m33 = -2F * f8;  m34 = (f4 + f5) * f8;
      m41 = 0.0F;  m42 = 0.0F;  m43 = 0.0F;  m44 = 1.0F;
   }

   public final void pretransform (Vector vector, Vector vector1)
   {  vector1.x = vector.x * m11 + vector.x * m12 + vector.x * m13 +
                  vector.x * m14;
      vector1.y = vector.y * m21 + vector.y * m22 + vector.y * m23 +
                  vector.y * m24;
      vector1.z = vector.z * m31 + vector.z * m32 + vector.z * m33 +
                  vector.z * m34;
      vector1.w = vector.w * m41 + vector.w * m42 + vector.w * m43 +
                  vector.w * m44;
   }

   public final void projection(float f, float f1, float f2, float f3, float f4,
                                float f5)
   { float f6 = 1.0F / (f1 - f);
     float f7 = 1.0F / (f2 - f3);
     float f8 = 1.0F / (f5 - f4);
     float f9 = f5 + f4;
      m11 = 2.0F * f4 * f6;  m12 = 0.0F;  m13 = (f1 + f) * f6;  m14 = 0.0F;
      m21 = 0.0F;  m22 = 2.0F * f4 * f7;  m23 = (f2 + f3) * f7;  m24 = 0.0F;
      m31 = 0.0F;  m32 = 0.0F;  m33 = -f9 * f8;  m34 = f9 * f8;
      m41 = 0.0F;  m42 = 0.0F;  m43 = -1F;  m44 = 0.0F;
   }

   public final void rotate (float f, Vector vector)  {}

   public final void rotateX (float f)
   { float f1 = (float)Math.cos (f);
     float f2 = (float)Math.sin (f);
      m11 = 1.0F;  m12 = 0.0F;  m13 = 0.0F;  m14 = 0.0F;
      m21 = 0.0F;  m22 = f1;    m23 = -f2;   m24 = 0.0F;
      m31 = 0.0F;  m32 = f2;    m33 = f1;    m34 = 0.0F;
      m41 = 0.0F;  m42 = 0.0F;  m43 = 0.0F;  m44 = 1.0F;
   }

   public final void rotateY (float f)
   { float f1 = (float)Math.cos (f);
     float f2 = (float)Math.sin (f);
      m11 = f1;    m12 = 0.0F;  m13 = f2;    m14 = 0.0F;
      m21 = 0.0F;  m22 = 1.0F;  m23 = 0.0F;  m24 = 0.0F;
      m31 = -f2;   m32 = 0.0F;  m33 = f1;    m34 = 0.0F;
      m41 = 0.0F;  m42 = 0.0F;  m43 = 0.0F;  m44 = 1.0F;
   }

   public final void rotateZ (float f)
   { float f1 = (float)Math.cos (f);
     float f2 = (float)Math.sin (f);
      m11 = f1;    m12 = -f2;   m13 = 0.0F;  m14 = 0.0F;
      m21 = f2;    m22 = f1;    m23 = 0.0F;  m24 = 0.0F;
      m31 = 0.0F;  m32 = 0.0F;  m33 = 1.0F;  m34 = 0.0F;
      m41 = 0.0F;  m42 = 0.0F;  m43 = 0.0F;  m44 = 1.0F;
   }

   public final void scale (float f)
   {  m11 = f;     m12 = 0.0F;  m13 = 0.0F;  m14 = 0.0F;
      m21 = 0.0F;  m22 = f;     m23 = 0.0F;  m24 = 0.0F;
      m31 = 0.0F;  m32 = 0.0F;  m33 = f;     m34 = 0.0F;
      m41 = 0.0F;  m42 = 0.0F;  m43 = 0.0F;  m44 = 1.0F;
   }

   public final void scale (float f, float f1, float f2)
   {  m11 = f;     m12 = 0.0F;  m13 = 0.0F;  m14 = 0.0F;
      m21 = 0.0F;  m22 = f1;    m23 = 0.0F;  m24 = 0.0F;
      m31 = 0.0F;  m32 = 0.0F;  m33 = f2;    m34 = 0.0F;
      m41 = 0.0F;  m42 = 0.0F;  m43 = 0.0F;  m44 = 1.0F;
   }

   public final void transform (Vector vector, Vector vector1)
   {  vector1.x = vector.x * m11 + vector.y * m12 + vector.z * m13 +
                  vector.w * m14;
      vector1.y = vector.x * m21 + vector.y * m22 + vector.z * m23 +
                  vector.w * m24;
      vector1.z = vector.x * m31 + vector.y * m32 + vector.z * m33 +
                  vector.w * m34;
      vector1.w = vector.x * m41 + vector.y * m42 + vector.z * m43 +
                  vector.w * m44;
   }

   public final void translate (float f, float f1, float f2)
   {  m11 = 1.0F;  m12 = 0.0F;  m13 = 0.0F;  m14 = f;
      m21 = 0.0F;  m22 = 1.0F;  m23 = 0.0F;  m24 = f1;
      m31 = 0.0F;  m32 = 0.0F;  m33 = 1.0F;  m34 = f2;
      m41 = 0.0F;  m42 = 0.0F;  m43 = 0.0F;  m44 = 1.0F;
   }

   public final void transpose (Matrix matrix)
   {  matrix.m11 = m11;  matrix.m12 = m21;  matrix.m13 = m31;  matrix.m14 = m41;
      matrix.m21 = m12;  matrix.m22 = m22;  matrix.m23 = m32;  matrix.m24 = m42;
      matrix.m31 = m13;  matrix.m32 = m23;  matrix.m33 = m33;  matrix.m34 = m43;
      matrix.m41 = m14;  matrix.m42 = m24;  matrix.m43 = m34;  matrix.m44 = m44;
   }

   public final void zero ()
   {  m11 = 0.0F;  m12 = 0.0F;  m13 = 0.0F;  m14 = 0.0F;
      m21 = 0.0F;  m22 = 0.0F;  m23 = 0.0F;  m24 = 0.0F;
      m31 = 0.0F;  m32 = 0.0F;  m33 = 0.0F;  m34 = 0.0F;
      m41 = 0.0F;  m42 = 0.0F;  m43 = 0.0F;  m44 = 0.0F;
   }

   public float m11, m12, m13, m14,
                m21, m22, m23, m24,
                m31, m32, m33, m34,
                m41, m42, m43, m44;
}