Package ej.microvg

Class Matrix

  • public class Matrix
extends Object
    Represents a 3x3 matrix for transforming coordinates.

    • Constructor Summary

      Constructors 
      Constructor Description
      Matrix()
      Creates an identity matrix.
      Matrix​(Matrix source)
      Creates a matrix that is a deep copy of the given matrix.

    • Method Summary

      All Methods Instance Methods Concrete Methods 
      Modifier and Type Method Description
      float[] getSNIContext()
      Returns the SNI context data of this matrix.
      void postConcat​(Matrix other)
      Postconcats the matrix with the specified matrix.
      void postRotate​(float degrees)
      Postconcats the matrix with the specified rotation.
      void postScale​(float sx, float sy)
      Postconcats the matrix with the specified scale.
      void postTranslate​(float dx, float dy)
      Postconcats the matrix with the specified translation.
      void preConcat​(Matrix other)
      Preconcats the matrix with the specified matrix.
      void preRotate​(float degrees)
      Preconcats the matrix with the specified rotation.
      void preScale​(float sx, float sy)
      Preconcats the matrix with the specified scale.
      void preTranslate​(float dx, float dy)
      Preconcats the matrix with the specified translation.
      void reset()
      Resets the matrix to identity.
      void set​(Matrix source)
      Deep copies the given matrix into this matrix.
      void setConcat​(Matrix a, Matrix b)
      Sets the matrix to the concatenation of the two specified matrices.
      void setRotate​(float degrees)
      Sets the matrix to rotate about (0,0) by the specified number of degrees.
      void setScale​(float sx, float sy)
      Sets the matrix to scale by (sx, sy).
      void setTranslate​(float dx, float dy)
      Sets the matrix to translate by (dx, dy).

    • Constructor Detail

      • Matrix

        public Matrix()
        Creates an identity matrix.

      • Matrix

        public Matrix​(Matrix source)
        Creates a matrix that is a deep copy of the given matrix.
        Parameters:
        source - the matrix to copy from

    • Method Detail

      • set

        public void set​(Matrix source)
        Deep copies the given matrix into this matrix.
        Parameters:
        source - the matrix to copy from

      • reset

        public void reset()
        Resets the matrix to identity.

      • setTranslate

        public void setTranslate​(float dx,
                         float dy)
        Sets the matrix to translate by (dx, dy).
        Parameters:
        dx - the translation on x
        dy - the translation on y

      • setScale

        public void setScale​(float sx,
                     float sy)
        Sets the matrix to scale by (sx, sy).
        Parameters:
        sx - the scale on x
        sy - the scale on y

      • setRotate

        public void setRotate​(float degrees)
        Sets the matrix to rotate about (0,0) by the specified number of degrees.
        Parameters:
        degrees - the degrees to rotate

      • setConcat

        public void setConcat​(Matrix a,
                      Matrix b)
        Sets the matrix to the concatenation of the two specified matrices.

        Either of the two matrices may also be the target matrix, that is matrixA.setConcat(matrixA, matrixB); is valid.

        Parameters:
        a - the first matrix
        b - the second matrix

      • preTranslate

        public void preTranslate​(float dx,
                         float dy)
        Preconcats the matrix with the specified translation. M' = M * T(dx, dy)
        Parameters:
        dx - the translation on x
        dy - the translation on y

      • preScale

        public void preScale​(float sx,
                     float sy)
        Preconcats the matrix with the specified scale. M' = M * S(sx, sy)
        Parameters:
        sx - the scale on x
        sy - the scale on y

      • preRotate

        public void preRotate​(float degrees)
        Preconcats the matrix with the specified rotation. M' = M * R(degrees)
        Parameters:
        degrees - the degrees to rotate

      • preConcat

        public void preConcat​(Matrix other)
        Preconcats the matrix with the specified matrix. M' = M * other
        Parameters:
        other - the matrix to concat with

      • postTranslate

        public void postTranslate​(float dx,
                          float dy)
        Postconcats the matrix with the specified translation. M' = T(dx, dy) * M
        Parameters:
        dx - the translation on x
        dy - the translation on y

      • postScale

        public void postScale​(float sx,
                      float sy)
        Postconcats the matrix with the specified scale. M' = S(sx, sy) * M
        Parameters:
        sx - the scale on x
        sy - the scale on y

      • postRotate

        public void postRotate​(float degrees)
        Postconcats the matrix with the specified rotation. M' = R(degrees) * M
        Parameters:
        degrees - the degrees to rotate

      • postConcat

        public void postConcat​(Matrix other)
        Postconcats the matrix with the specified matrix. M' = other * M
        Parameters:
        other - the matrix to concat with

      • getSNIContext

        public float[] getSNIContext()
        Returns the SNI context data of this matrix.

        The SNI context can be used to call a native method with SNI. This allows to identify and to use an matrix in the native world in order to perform operations with this matrix.

        The data format is implementation specific.

        Returns:
        the SNI context of this matrix.