affinetransform.java

this gcc-g++-3.3.1.tar.gz is a source file of gcc, you can learn more about gcc through this codes f

  /**
   * Returns a shearing transform (points are shifted in the x direction based
   * on a factor of their y coordinate, and in the y direction as a factor of
   * their x coordinate):
   * <pre>
   * [  1  shx 0 ]
   * [ shy  1  0 ]
   * [  0   0  1 ]
   * </pre>
   *
   * @param shx the x shearing factor
   * @param shy the y shearing factor
   * @return the shearing transform
   */
  public static AffineTransform getShearInstance(double shx, double shy)
  {
    AffineTransform t = new AffineTransform();
    t.setToShear(shx, shy);
    return t;
  }

  /**
   * Returns the type of this transform. The result is always valid, although
   * it may not be the simplest interpretation (in other words, there are
   * sequences of transforms which reduce to something simpler, which this
   * does not always detect). The result is either TYPE_GENERAL_TRANSFORM,
   * or a bit-wise combination of TYPE_TRANSLATION, the mutually exclusive
   * TYPE_*_ROTATIONs, and the mutually exclusive TYPE_*_SCALEs.
   *
   * @see #TYPE_IDENTITY
   * @see #TYPE_TRANSLATION
   * @see #TYPE_UNIFORM_SCALE
   * @see #TYPE_GENERAL_SCALE
   * @see #TYPE_QUADRANT_ROTATION
   * @see #TYPE_GENERAL_ROTATION
   * @see #TYPE_GENERAL_TRANSFORM
   */
  public int getType()
  {
    return type;
  }

  /**
   * Return the determinant of this transform matrix. If the determinant is
   * non-zero, the transform is invertible; otherwise operations which require
   * an inverse throw a NoninvertibleTransformException. A result very near
   * zero, due to rounding errors, may indicate that inversion results do not
   * carry enough precision to be meaningful.
   *
   * <p>If this is a uniform scale transformation, the determinant also
   * represents the squared value of the scale. Otherwise, it carries little
   * additional meaning. The determinant is calculated as:
   * <pre>
   * | m00 m01 m02 |
   * | m10 m11 m12 | = m00 * m11 - m01 * m10
   * |  0   0   1  |
   * </pre>
   *
   * @return the determinant
   * @see #createInverse()
   */
  public double getDeterminant()
  {
    return m00 * m11 - m01 * m10;
  }

  /**
   * Return the matrix of values used in this transform. If the matrix has
   * fewer than 6 entries, only the scale and shear factors are returned;
   * otherwise the translation factors are copied as well. The resulting
   * values are:
   * <pre>
   * [ d[0] d[2] (d[4]) ]
   * [ d[1] d[3] (d[5]) ]
   * [  0     0    1    ]
   * </pre>
   *
   * @param d the matrix to store the results into; with 4 (6) entries
   * @throws NullPointerException if d is null
   * @throws ArrayIndexOutOfBoundsException if d is too small
   */
  public void getMatrix(double[] d)
  {
    d[0] = m00;
    d[1] = m10;
    d[2] = m01;
    d[3] = m11;
    if (d.length >= 6)
      {
        d[4] = m02;
        d[5] = m12;
      }
  }

  /**
   * Returns the X coordinate scaling factor of the matrix.
   *
   * @return m00
   * @see #getMatrix(double[])
   */
  public double getScaleX()
  {
    return m00;
  }

  /**
   * Returns the Y coordinate scaling factor of the matrix.
   *
   * @return m11
   * @see #getMatrix(double[])
   */
  public double getScaleY()
  {
    return m11;
  }

  /**
   * Returns the X coordinate shearing factor of the matrix.
   *
   * @return m01
   * @see #getMatrix(double[])
   */
  public double getShearX()
  {
    return m01;
  }

  /**
   * Returns the Y coordinate shearing factor of the matrix.
   *
   * @return m10
   * @see #getMatrix(double[])
   */
  public double getShearY()
  {
    return m10;
  }

  /**
   * Returns the X coordinate translation factor of the matrix.
   *
   * @return m02
   * @see #getMatrix(double[])
   */
  public double getTranslateX()
  {
    return m02;
  }

  /**
   * Returns the Y coordinate translation factor of the matrix.
   *
   * @return m12
   * @see #getMatrix(double[])
   */
  public double getTranslateY()
  {
    return m12;
  }

  /**
   * Concatenate a translation onto this transform. This is equivalent, but
   * more efficient than
   * <code>concatenate(AffineTransform.getTranslateInstance(tx, ty))</code>.
   *
   * @param tx the x translation distance
   * @param ty the y translation distance
   * @see #getTranslateInstance(double, double)
   * @see #concatenate(AffineTransform)
   */
  public void translate(double tx, double ty)
  {
    m02 += tx * m00 + ty * m01;
    m12 += tx * m10 + ty * m11;
    updateType();
  }

  /**
   * Concatenate a rotation onto this transform. This is equivalent, but
   * more efficient than
   * <code>concatenate(AffineTransform.getRotateInstance(theta))</code>.
   *
   * @param theta the rotation angle
   * @see #getRotateInstance(double)
   * @see #concatenate(AffineTransform)
   */
  public void rotate(double theta)
  {
    double c = Math.cos(theta);
    double s = Math.sin(theta);
    double n00 = m00 *  c + m01 * s;
    double n01 = m00 * -s + m01 * c;
    double n10 = m10 *  c + m11 * s;
    double n11 = m10 * -s + m11 * c;
    m00 = n00;
    m01 = n01;
    m10 = n10;
    m11 = n11;
    updateType();
  }

  /**
   * Concatenate a rotation about a point onto this transform. This is
   * equivalent, but more efficient than
   * <code>concatenate(AffineTransform.getRotateInstance(theta, x, y))</code>.
   *
   * @param theta the rotation angle
   * @param x the x coordinate of the pivot point
   * @param y the y coordinate of the pivot point
   * @see #getRotateInstance(double, double, double)
   * @see #concatenate(AffineTransform)
   */
  public void rotate(double theta, double x, double y)
  {
    translate(x, y);
    rotate(theta);
    translate(-x, -y);
  }

  /**
   * Concatenate a scale onto this transform. This is equivalent, but more
   * efficient than
   * <code>concatenate(AffineTransform.getScaleInstance(sx, sy))</code>.
   *
   * @param sx the x scaling factor
   * @param sy the y scaling factor
   * @see #getScaleInstance(double, double)
   * @see #concatenate(AffineTransform)
   */
  public void scale(double sx, double sy)
  {
    m00 *= sx;
    m01 *= sy;
    m10 *= sx;
    m11 *= sy;
    updateType();
  }

  /**
   * Concatenate a shearing onto this transform. This is equivalent, but more
   * efficient than
   * <code>concatenate(AffineTransform.getShearInstance(sx, sy))</code>.
   *
   * @param shx the x shearing factor
   * @param shy the y shearing factor
   * @see #getShearInstance(double, double)
   * @see #concatenate(AffineTransform)
   */
  public void shear(double shx, double shy)
  {
    double n00 = m00 + shx * m01;
    double n01 = shx * m00 + m01;
    double n10 = m10 * shy + m11;
    double n11 = shx * m10 + m11;
    m00 = n00;
    m01 = n01;
    m10 = n10;
    m11 = n11;
    updateType();
  }

  /**
   * Reset this transform to the identity (no transformation):
   * <pre>
   * [ 1 0 0 ]
   * [ 0 1 0 ]
   * [ 0 0 1 ]
   * </pre>
   */
  public void setToIdentity()
  {
    m00 = m11 = 1;
    m01 = m02 = m10 = m12 = 0;
    type = TYPE_IDENTITY;
  }

  /**
   * Set this transform to a translation:
   * <pre>
   * [ 1 0 tx ]
   * [ 0 1 ty ]
   * [ 0 0 1  ]
   * </pre>
   *
   * @param tx the x translation distance
   * @param ty the y translation distance
   */
  public void setToTranslation(double tx, double ty)
  {
    m00 = m11 = 1;
    m01 = m10 = 0;
    m02 = tx;
    m12 = ty;
    type = (tx == 0 && ty == 0) ? TYPE_UNIFORM_SCALE : TYPE_TRANSLATION;
  }

  /**
   * Set this transform to a rotation. A positive angle (in radians) rotates
   * the positive x-axis to the positive y-axis:
   * <pre>
   * [ cos(theta) -sin(theta) 0 ]
   * [ sin(theta)  cos(theta) 0 ]
   * [     0           0      1 ]
   * </pre>
   *
   * @param theta the rotation angle
   */
  public void setToRotation(double theta)
  {
    double c = Math.cos(theta);
    double s = Math.sin(theta);
    m00 = c;
    m01 = -s;
    m02 = 0;
    m10 = s;
    m11 = c;
    m12 = 0;
    type = (c == 1 ? TYPE_IDENTITY
            : c == 0 || c == -1 ? TYPE_QUADRANT_ROTATION
            : TYPE_GENERAL_ROTATION);
  }

  /**
   * Set this transform to a rotation about a point. A positive angle (in
   * radians) rotates the positive x-axis to the positive y-axis. This is the
   * same as calling:
   * <pre>
   * tx.setToTranslation(x, y);
   * tx.rotate(theta);
   * tx.translate(-x, -y);
   * </pre>
   *
   * <p>The resulting matrix is: 
   * <pre>
   * [ cos(theta) -sin(theta) x-x*cos+y*sin ]
   * [ sin(theta)  cos(theta) y-x*sin-y*cos ]
   * [     0           0            1       ]
   * </pre>
   *
   * @param theta the rotation angle
   * @param x the x coordinate of the pivot point
   * @param y the y coordinate of the pivot point
   */
  public void setToRotation(double theta, double x, double y)
  {
    double c = Math.cos(theta);
    double s = Math.sin(theta);
    m00 = c;
    m01 = -s;
    m02 = x - x * c + y * s;
    m10 = s;
    m11 = c;
    m12 = y - x * s - y * c;
    updateType();
  }

  /**
   * Set this transform to a scale:
   * <pre>
   * [ sx 0  0 ]
   * [ 0  sy 0 ]
   * [ 0  0  1 ]
   * </pre>
   *
   * @param sx the x scaling factor
   * @param sy the y scaling factor
   */
  public void setToScale(double sx, double sy)
  {
    m00 = sx;
    m01 = m02 = m10 = m12 = 0;
    m11 = sy;
    type = (sx != sy ? TYPE_GENERAL_SCALE
            : sx == 1 ? TYPE_IDENTITY : TYPE_UNIFORM_SCALE);
  }

  /**
   * Set this transform to a shear (points are shifted in the x direction based
   * on a factor of their y coordinate, and in the y direction as a factor of
   * their x coordinate):
   * <pre>
   * [  1  shx 0 ]
   * [ shy  1  0 ]
   * [  0   0  1 ]
   * </pre>
   *
   * @param shx the x shearing factor
   * @param shy the y shearing factor
   */
  public void setToShear(double shx, double shy)
  {
    m00 = m11 = 1;
    m01 = shx;
    m10 = shy;
    m02 = m12 = 0;
    updateType();
  }

  /**
   * Set this transform to a copy of the given one.
   *
   * @param tx the transform to copy
   * @throws NullPointerException if tx is null
   */
  public void setTransform(AffineTransform tx)
  {
    m00 = tx.m00;
    m01 = tx.m01;
    m02 = tx.m02;
    m10 = tx.m10;
    m11 = tx.m11;
    m12 = tx.m12;
    type = tx.type;
  }

  /**
   * Set this transform to the given values:
   * <pre>
   * [ m00 m01 m02 ]
   * [ m10 m11 m12 ]
   * [  0   0   1  ]
   * </pre>
   *
   * @param m00 the x scaling component
   * @param m10 the y shearing component
   * @param m01 the x shearing component
   * @param m11 the y scaling component
   * @param m02 the x translation component
   * @param m12 the y translation component
   */
  public void setTransform(double m00, double m10, double m01,
                           double m11, double m02, double m12)
  {
    this.m00 = m00;
    this.m10 = m10;
    this.m01 = m01;
    this.m11 = m11;
    this.m02 = m02;
    this.m12 = m12;
    updateType();
  }

  /**
   * Set this transform to the result of performing the original version of
   * this followed by tx. This is commonly used when chaining transformations
   * from one space to another. In matrix form:
   * <pre>
   * [ this ] = [ this ] x [ tx ]
   * </pre>
   *
   * @param tx the transform to concatenate
   * @throws NullPointerException if tx is null
   * @see #preConcatenate(AffineTransform)
   */
  public void concatenate(AffineTransform tx)
  {
    double n00 = m00 * tx.m00 + m01 * tx.m10;
    double n01 = m00 * tx.m01 + m01 * tx.m11;
    double n02 = m00 * tx.m02 + m01 * tx.m12 + m02;
    double n10 = m10 * tx.m00 + m11 * tx.m10;
    double n11 = m10 * tx.m01 + m11 * tx.m11;
    double n12 = m10 * tx.m02 + m11 * tx.m12 + m12;
    m00 = n00;
    m01 = n01;
    m02 = n02;
    m10 = n10;
    m11 = n11;
    m12 = n12;
    updateType();
  }

  /**
   * Set this transform to the result of performing tx followed by the
   * original version of this. This is less common than normal concatenation,
   * but can still be used to chain transformations from one space to another.
   * In matrix form:
   * <pre>
   * [ this ] = [ tx ] x [ this ]
   * </pre>
   *
   * @param tx the transform to concatenate
   * @throws NullPointerException if tx is null
   * @see #concatenate(AffineTransform)
   */
  public void preConcatenate(AffineTransform tx)
  {
    double n00 = tx.m00 * m00 + tx.m01 * m10;
    double n01 = tx.m00 * m01 + tx.m01 * m11;
    double n02 = tx.m00 * m02 + tx.m01 * m12 + tx.m02;
    double n10 = tx.m10 * m00 + tx.m11 * m10;