| /* Ceres Solver - A fast non-linear least squares minimizer | |
| * Copyright 2019 Google Inc. All rights reserved. | |
| * http://ceres-solver.org/ | |
| * | |
| * Redistribution and use in source and binary forms, with or without | |
| * modification, are permitted provided that the following conditions are met: | |
| * | |
| * - Redistributions of source code must retain the above copyright notice, | |
| * this list of conditions and the following disclaimer. | |
| * - Redistributions in binary form must reproduce the above copyright notice, | |
| * this list of conditions and the following disclaimer in the documentation | |
| * and/or other materials provided with the distribution. | |
| * - Neither the name of Google Inc. nor the names of its contributors may be | |
| * used to endorse or promote products derived from this software without | |
| * specific prior written permission. | |
| * | |
| * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" | |
| * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE | |
| * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE | |
| * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE | |
| * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR | |
| * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF | |
| * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS | |
| * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN | |
| * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) | |
| * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE | |
| * POSSIBILITY OF SUCH DAMAGE. | |
| * | |
| * Author: mierle@gmail.com (Keir Mierle) | |
| * | |
| * A minimal C API for Ceres. Not all functionality is included. This API is | |
| * not intended for clients of Ceres, but is instead intended for easing the | |
| * process of binding Ceres to other languages. | |
| * | |
| * Currently this is a work in progress. | |
| */ | |
| // clang-format off | |
| // clang-format on | |
| extern "C" { | |
| /* Init the Ceres private data. Must be called before anything else. */ | |
| CERES_EXPORT void ceres_init(); | |
| /* Equivalent to CostFunction::Evaluate() in the C++ API. | |
| * | |
| * The user may keep private information inside the opaque user_data object. | |
| * The pointer here is the same one passed in the ceres_add_residual_block(). | |
| */ | |
| typedef int (*ceres_cost_function_t)(void* user_data, | |
| double** parameters, | |
| double* residuals, | |
| double** jacobians); | |
| /* Equivalent to LossFunction::Evaluate() from the C++ API. */ | |
| typedef void (*ceres_loss_function_t)(void* user_data, | |
| double squared_norm, | |
| double out[3]); | |
| /* Create callback data for Ceres' stock loss functions. | |
| * | |
| * Ceres has several loss functions available by default, and these functions | |
| * expose those to the C API. To use the stock loss functions, call | |
| * ceres_create_*_loss_data(), which internally creates an instance of one of | |
| * the stock loss functions (for example ceres::CauchyLoss), and pass the | |
| * returned "loss_function_data" along with the ceres_stock_loss_function to | |
| * ceres_add_residual_block(). | |
| * | |
| * For example: | |
| * | |
| * void* cauchy_loss_function_data = | |
| * ceres_create_cauchy_loss_function_data(1.2, 0.0); | |
| * ceres_problem_add_residual_block( | |
| * problem, | |
| * my_cost_function, | |
| * my_cost_function_data, | |
| * ceres_stock_loss_function, | |
| * cauchy_loss_function_data, | |
| * 1, | |
| * 2, | |
| * parameter_sizes, | |
| * parameter_pointers); | |
| * ... | |
| * ceres_free_stock_loss_function_data(cauchy_loss_function_data); | |
| * | |
| * See loss_function.h for the details of each loss function. | |
| */ | |
| CERES_EXPORT void* ceres_create_huber_loss_function_data(double a); | |
| CERES_EXPORT void* ceres_create_softl1_loss_function_data(double a); | |
| CERES_EXPORT void* ceres_create_cauchy_loss_function_data(double a); | |
| CERES_EXPORT void* ceres_create_arctan_loss_function_data(double a); | |
| CERES_EXPORT void* ceres_create_tolerant_loss_function_data(double a, double b); | |
| /* Free the given stock loss function data. */ | |
| CERES_EXPORT void ceres_free_stock_loss_function_data(void* loss_function_data); | |
| /* This is an implementation of ceres_loss_function_t contained within Ceres | |
| * itself, intended as a way to access the various stock Ceres loss functions | |
| * from the C API. This should be passed to ceres_add_residual() below, in | |
| * combination with a user_data pointer generated by | |
| * ceres_create_stock_loss_function() above. */ | |
| CERES_EXPORT void ceres_stock_loss_function(void* user_data, | |
| double squared_norm, | |
| double out[3]); | |
| /* Equivalent to Problem from the C++ API. */ | |
| struct ceres_problem_s; | |
| typedef struct ceres_problem_s ceres_problem_t; | |
| struct ceres_residual_block_id_s; | |
| typedef struct ceres_residual_block_id_s ceres_residual_block_id_t; | |
| /* Create and destroy a problem */ | |
| /* TODO(keir): Add options for the problem. */ | |
| CERES_EXPORT ceres_problem_t* ceres_create_problem(); | |
| CERES_EXPORT void ceres_free_problem(ceres_problem_t* problem); | |
| /* Add a residual block. */ | |
| CERES_EXPORT ceres_residual_block_id_t* ceres_problem_add_residual_block( | |
| ceres_problem_t* problem, | |
| ceres_cost_function_t cost_function, | |
| void* cost_function_data, | |
| ceres_loss_function_t loss_function, | |
| void* loss_function_data, | |
| int num_residuals, | |
| int num_parameter_blocks, | |
| int* parameter_block_sizes, | |
| double** parameters); | |
| CERES_EXPORT void ceres_solve(ceres_problem_t* problem); | |
| /* TODO(keir): Figure out a way to pass a config in. */ | |
| } | |