mirror of
https://github.com/tesseract-ocr/tesseract.git
synced 2024-12-19 11:58:15 +08:00
64 lines
2.4 KiB
C++
64 lines
2.4 KiB
C++
|
/******************************************************************************
|
||
|
|
** Filename: xform2d.c
|
||
|
|
** Purpose: Library routines for performing 2D point transformations
|
||
|
|
** Author: Dan Johnson
|
||
|
|
** History: Fri Sep 22 09:54:17 1989, DSJ, Created.
|
||
|
|
**
|
||
|
|
** (c) Copyright Hewlett-Packard Company, 1988.
|
||
|
|
** Licensed under the Apache License, Version 2.0 (the "License");
|
||
|
|
** you may not use this file except in compliance with the License.
|
||
|
|
** You may obtain a copy of the License at
|
||
|
|
** http://www.apache.org/licenses/LICENSE-2.0
|
||
|
|
** Unless required by applicable law or agreed to in writing, software
|
||
|
|
** distributed under the License is distributed on an "AS IS" BASIS,
|
||
|
|
** WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
|
||
|
|
** See the License for the specific language governing permissions and
|
||
|
|
** limitations under the License.
|
||
|
|
******************************************************************************/
|
||
|
|
/**----------------------------------------------------------------------------
|
||
|
|
Include Files and Type Defines
|
||
|
|
----------------------------------------------------------------------------**/
|
||
|
|
#include "xform2d.h"
|
||
|
|
#include <math.h>
|
||
|
|
|
||
|
|
/**----------------------------------------------------------------------------
|
||
|
|
Public Code
|
||
|
|
----------------------------------------------------------------------------**/
|
||
|
|
/*---------------------------------------------------------------------------*/
|
||
|
|
void RotateMatrix(MATRIX_2D_PTR Matrix, FLOAT32 Angle) {
|
||
|
|
/*
|
||
|
|
** Parameters:
|
||
|
|
** Matrix transformation matrix to rotate
|
||
|
|
** Angle angle to rotate matrix
|
||
|
|
** Globals: none
|
||
|
|
** Operation:
|
||
|
|
** Rotate the coordinate system (as specified by Matrix) about
|
||
|
|
** its origin by Angle radians. In matrix notation the
|
||
|
|
** effect is as follows:
|
||
|
|
**
|
||
|
|
** Matrix = R X Matrix
|
||
|
|
**
|
||
|
|
** where R is the following matrix
|
||
|
|
**
|
||
|
|
** cos Angle sin Angle 0
|
||
|
|
** -sin Angle cos Angle 0
|
||
|
|
** 0 0 1
|
||
|
|
** Return: none
|
||
|
|
** Exceptions: none
|
||
|
|
** History: 7/27/89, DSJ, Create.
|
||
|
|
*/
|
||
|
|
FLOAT32 Cos, Sin;
|
||
|
|
FLOAT32 NewA, NewB;
|
||
|
|
|
||
|
|
Cos = cos ((double) Angle);
|
||
|
|
Sin = sin ((double) Angle);
|
||
|
|
|
||
|
|
NewA = Matrix->a * Cos + Matrix->c * Sin;
|
||
|
|
NewB = Matrix->b * Cos + Matrix->d * Sin;
|
||
|
|
Matrix->c = Matrix->a * -Sin + Matrix->c * Cos;
|
||
|
|
Matrix->d = Matrix->b * -Sin + Matrix->d * Cos;
|
||
|
|
Matrix->a = NewA;
|
||
|
|
Matrix->b = NewB;
|
||
|
|
|
||
|
|
} /* RotateMatrix */
|