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hom_mat2d_translateHomMat2dTranslateHomMat2dTranslatehom_mat2d_translateT_hom_mat2d_translate🔗

Short description🔗

hom_mat2d_translateHomMat2dTranslateHomMat2dTranslatehom_mat2d_translateT_hom_mat2d_translate — Add a translation to a homogeneous 2D transformation matrix.

Signature🔗

hom_mat2d_translate( hom_mat2d HomMat2D, point.x Tx, point.y Ty, out hom_mat2d HomMat2DTranslate )void HomMat2dTranslate( const HTuple& HomMat2D, const HTuple& Tx, const HTuple& Ty, HTuple* HomMat2DTranslate )static void HOperatorSet.HomMat2dTranslate( HTuple homMat2D, HTuple tx, HTuple ty, out HTuple homMat2DTranslate )def hom_mat2d_translate( hom_mat_2d: Sequence[float], tx: Union[float, int], ty: Union[float, int] ) -> Sequence[float]

Herror T_hom_mat2d_translate( const Htuple HomMat2D, const Htuple Tx, const Htuple Ty, Htuple* HomMat2DTranslate )

HHomMat2D HHomMat2D::HomMat2dTranslate( const HTuple& Tx, const HTuple& Ty ) const

HHomMat2D HHomMat2D::HomMat2dTranslate( double Tx, double Ty ) const

HHomMat2D HHomMat2D.HomMat2dTranslate( HTuple tx, HTuple ty )

HHomMat2D HHomMat2D.HomMat2dTranslate( double tx, double ty )

Description🔗

hom_mat2d_translateHomMat2dTranslate adds a translation by the vector t = (Txtxtx,Tytyty) to the homogeneous 2D transformation matrix HomMat2DhomMat2Dhom_mat_2d and returns the resulting matrix in HomMat2DTranslatehomMat2DTranslatehom_mat_2dtranslate. The translation is performed relative to the global (i.e., fixed) coordinate system; this corresponds to the following chain of transformation matrices:

\[\begin{eqnarray*} \textrm{HomMat2DTranslate} = \mvHomMatrixTwoDRotTrans{\mvMatrixPlain{1 & 0 \\ 0 & 1}} {\mvTranslationVectorVar{}{}} \cdot \textrm{HomMat2D} \qquad \mvTranslationVectorVar{}{} = \mvVectorTwoD{\textrm{Tx}}{\textrm{Ty}} \end{eqnarray*}\]

To perform the transformation in the local coordinate system, i.e., the one described by HomMat2DhomMat2Dhom_mat_2d, use hom_mat2d_translate_localHomMat2dTranslateLocal.

Attention🔗

It should be noted that homogeneous transformation matrices refer to a general right-handed mathematical coordinate system. If a homogeneous transformation matrix is used to transform images, regions, XLD contours, or any other data that has been extracted from images, the row coordinates of the transformation must be passed in the x coordinates, while the column coordinates must be passed in the y coordinates. Consequently, the order of passing row and column coordinates follows the usual order (Rowrowrow,Columncolumncolumn). This convention is essential to obtain a right-handed coordinate system for the transformation of iconic data, and consequently to ensure in particular that rotations are performed in the correct mathematical direction.

Note that homogeneous matrices are stored row-by-row as a tuple; the last row is usually not stored because it is identical for all homogeneous matrices that describe an affine transformation. For example, the homogeneous matrix \(\mvHomMatrixTwoDElements{ra & rb & tc \\ rd & re & tf}\) is stored as the tuple [ra, rb, tc, rd, re, tf]. However, it is also possible to process full 3×3 matrices, which represent a projective 2D transformation.

Execution information🔗

Execution information

  • Multithreading type: reentrant (runs in parallel with non-exclusive operators).

  • Multithreading scope: global (may be called from any thread).

  • Processed without parallelization.

Parameters🔗

HomMat2DhomMat2Dhom_mat_2d (input_control) hom_mat2d → (real)HTuple (double)HHomMat2D, HTuple (double)Sequence[float]Htuple (double)

Input transformation matrix.

Txtxtx (input_control) point.x → (real / integer)HTuple (double / Hlong)HTuple (double / int / long)Union[float, int]Htuple (double / Hlong)

Translation along the x-axis.

Default: 6464
Suggested values: 0, 16, 32, 64, 128, 256, 512, 10240, 16, 32, 64, 128, 256, 512, 1024

Tytyty (input_control) point.y → (real / integer)HTuple (double / Hlong)HTuple (double / int / long)Union[float, int]Htuple (double / Hlong)

Translation along the y-axis.

Default: 6464
Suggested values: 0, 16, 32, 64, 128, 256, 512, 10240, 16, 32, 64, 128, 256, 512, 1024

HomMat2DTranslatehomMat2DTranslatehom_mat_2dtranslate (output_control) hom_mat2d → (real)HTuple (double)HHomMat2D, HTuple (double)Sequence[float]Htuple (double)

Output transformation matrix.

Result🔗

If the parameters are valid, the operator hom_mat2d_translateHomMat2dTranslate returns 2 (H_MSG_TRUE). If necessary, an exception is raised.

Combinations with other operators🔗

Combinations

Possible predecessors

hom_mat2d_identityHomMat2dIdentity, hom_mat2d_translateHomMat2dTranslate, hom_mat2d_scaleHomMat2dScale, hom_mat2d_rotateHomMat2dRotate, hom_mat2d_slantHomMat2dSlant, hom_mat2d_reflectHomMat2dReflect

Possible successors

hom_mat2d_translateHomMat2dTranslate, hom_mat2d_scaleHomMat2dScale, hom_mat2d_rotateHomMat2dRotate, hom_mat2d_slantHomMat2dSlant, hom_mat2d_reflectHomMat2dReflect

See also

hom_mat2d_translate_localHomMat2dTranslateLocal

Module🔗

Foundation