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Diffstat (limited to 'include/utils/LinearTransform.h')
-rw-r--r-- | include/utils/LinearTransform.h | 64 |
1 files changed, 0 insertions, 64 deletions
diff --git a/include/utils/LinearTransform.h b/include/utils/LinearTransform.h deleted file mode 100644 index 04cb355..0000000 --- a/include/utils/LinearTransform.h +++ /dev/null @@ -1,64 +0,0 @@ -/* - * Copyright (C) 2011 The Android Open Source Project - * - * 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. - */ - -#ifndef _LIBS_UTILS_LINEAR_TRANSFORM_H -#define _LIBS_UTILS_LINEAR_TRANSFORM_H - -#include <stdint.h> - -namespace android { - -// LinearTransform defines a structure which hold the definition of a -// transformation from single dimensional coordinate system A into coordinate -// system B (and back again). Values in A and in B are 64 bit, the linear -// scale factor is expressed as a rational number using two 32 bit values. -// -// Specifically, let -// f(a) = b -// F(b) = f^-1(b) = a -// then -// -// f(a) = (((a - a_zero) * a_to_b_numer) / a_to_b_denom) + b_zero; -// -// and -// -// F(b) = (((b - b_zero) * a_to_b_denom) / a_to_b_numer) + a_zero; -// -struct LinearTransform { - int64_t a_zero; - int64_t b_zero; - int32_t a_to_b_numer; - uint32_t a_to_b_denom; - - // Transform from A->B - // Returns true on success, or false in the case of a singularity or an - // overflow. - bool doForwardTransform(int64_t a_in, int64_t* b_out) const; - - // Transform from B->A - // Returns true on success, or false in the case of a singularity or an - // overflow. - bool doReverseTransform(int64_t b_in, int64_t* a_out) const; - - // Helpers which will reduce the fraction N/D using Euclid's method. - template <class T> static void reduce(T* N, T* D); - static void reduce(int32_t* N, uint32_t* D); -}; - - -} - -#endif // _LIBS_UTILS_LINEAR_TRANSFORM_H |