1// Ceres Solver - A fast non-linear least squares minimizer 2// Copyright 2010, 2011, 2012 Google Inc. All rights reserved. 3// http://code.google.com/p/ceres-solver/ 4// 5// Redistribution and use in source and binary forms, with or without 6// modification, are permitted provided that the following conditions are met: 7// 8// * Redistributions of source code must retain the above copyright notice, 9// this list of conditions and the following disclaimer. 10// * Redistributions in binary form must reproduce the above copyright notice, 11// this list of conditions and the following disclaimer in the documentation 12// and/or other materials provided with the distribution. 13// * Neither the name of Google Inc. nor the names of its contributors may be 14// used to endorse or promote products derived from this software without 15// specific prior written permission. 16// 17// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" 18// AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 19// IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 20// ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE 21// LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 22// CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 23// SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 24// INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 25// CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 26// ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 27// POSSIBILITY OF SUCH DAMAGE. 28// 29// Author: sameeragarwal@google.com (Sameer Agarwal) 30// 31// Block structure objects are used to carry information about the 32// dense block structure of sparse matrices. The BlockSparseMatrix 33// object uses the BlockStructure objects to keep track of the matrix 34// structure and operate upon it. This allows us to use more cache 35// friendly block oriented linear algebra operations on the matrix 36// instead of accessing it one scalar entry at a time. 37 38#ifndef CERES_INTERNAL_BLOCK_STRUCTURE_H_ 39#define CERES_INTERNAL_BLOCK_STRUCTURE_H_ 40 41#include <vector> 42#include "ceres/internal/port.h" 43#include "ceres/types.h" 44 45namespace ceres { 46namespace internal { 47 48class BlockStructureProto; 49 50typedef int16 BlockSize; 51 52struct Block { 53 Block() : size(-1), position(-1) {} 54 Block(int size_, int position_) : size(size_), position(position_) {} 55 56 BlockSize size; 57 int position; // Position along the row/column. 58}; 59 60struct Cell { 61 Cell() : block_id(-1), position(-1) {} 62 Cell(int block_id_, int position_) 63 : block_id(block_id_), position(position_) {} 64 65 // Column or row block id as the case maybe. 66 int block_id; 67 // Where in the values array of the jacobian is this cell located. 68 int position; 69}; 70 71// Order cell by their block_id; 72bool CellLessThan(const Cell& lhs, const Cell& rhs); 73 74struct CompressedList { 75 Block block; 76 vector<Cell> cells; 77}; 78 79typedef CompressedList CompressedRow; 80typedef CompressedList CompressedColumn; 81 82struct CompressedRowBlockStructure { 83 vector<Block> cols; 84 vector<CompressedRow> rows; 85}; 86 87struct CompressedColumnBlockStructure { 88 vector<Block> rows; 89 vector<CompressedColumn> cols; 90}; 91 92// Deserialize the given block structure proto to the given block structure. 93// Destroys previous contents of block_structure. 94void ProtoToBlockStructure(const BlockStructureProto &proto, 95 CompressedRowBlockStructure *block_structure); 96 97// Serialize the given block structure to the given proto. Destroys previous 98// contents of proto. 99void BlockStructureToProto(const CompressedRowBlockStructure &block_structure, 100 BlockStructureProto *proto); 101 102} // namespace internal 103} // namespace ceres 104 105#endif // CERES_INTERNAL_BLOCK_STRUCTURE_H_ 106