Add solver for april tag mapping
Takes in robot locations (at control loop frequency), and less frequent
localizations off of april tags. Builds a graph of constraints between
subsequent target detections and solves for the optimal target locations
on the field.
Change-Id: I1256f5914b7656d9e14735f9d994572688c3aaa8
Signed-off-by: Milind Upadhyay <milind.upadhyay@gmail.com>
diff --git a/frc971/vision/ceres/read_g2o.h b/frc971/vision/ceres/read_g2o.h
new file mode 100644
index 0000000..fea32e9
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+++ b/frc971/vision/ceres/read_g2o.h
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+// Ceres Solver - A fast non-linear least squares minimizer
+// Copyright 2016 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: vitus@google.com (Michael Vitus)
+//
+// Reads a file in the g2o filename format that describes a pose graph problem.
+
+#ifndef EXAMPLES_CERES_READ_G2O_H_
+#define EXAMPLES_CERES_READ_G2O_H_
+
+#include <fstream>
+#include <string>
+
+#include "glog/logging.h"
+
+namespace ceres {
+namespace examples {
+
+// Reads a single pose from the input and inserts it into the map. Returns false
+// if there is a duplicate entry.
+template <typename Pose, typename Allocator>
+bool ReadVertex(std::ifstream* infile,
+ std::map<int, Pose, std::less<int>, Allocator>* poses) {
+ int id;
+ Pose pose;
+ *infile >> id >> pose;
+
+ // Ensure we don't have duplicate poses.
+ if (poses->find(id) != poses->end()) {
+ LOG(ERROR) << "Duplicate vertex with ID: " << id;
+ return false;
+ }
+ (*poses)[id] = pose;
+
+ return true;
+}
+
+// Reads the contraints between two vertices in the pose graph
+template <typename Constraint, typename Allocator>
+void ReadConstraint(std::ifstream* infile,
+ std::vector<Constraint, Allocator>* constraints) {
+ Constraint constraint;
+ *infile >> constraint;
+
+ constraints->push_back(constraint);
+}
+
+// Reads a file in the g2o filename format that describes a pose graph
+// problem. The g2o format consists of two entries, vertices and constraints.
+//
+// In 2D, a vertex is defined as follows:
+//
+// VERTEX_SE2 ID x_meters y_meters yaw_radians
+//
+// A constraint is defined as follows:
+//
+// EDGE_SE2 ID_A ID_B A_x_B A_y_B A_yaw_B I_11 I_12 I_13 I_22 I_23 I_33
+//
+// where I_ij is the (i, j)-th entry of the information matrix for the
+// measurement.
+//
+//
+// In 3D, a vertex is defined as follows:
+//
+// VERTEX_SE3:QUAT ID x y z q_x q_y q_z q_w
+//
+// where the quaternion is in Hamilton form.
+// A constraint is defined as follows:
+//
+// EDGE_SE3:QUAT ID_a ID_b x_ab y_ab z_ab q_x_ab q_y_ab q_z_ab q_w_ab I_11 I_12 I_13 ... I_16 I_22 I_23 ... I_26 ... I_66 // NOLINT
+//
+// where I_ij is the (i, j)-th entry of the information matrix for the
+// measurement. Only the upper-triangular part is stored. The measurement order
+// is the delta position followed by the delta orientation.
+template <typename Pose,
+ typename Constraint,
+ typename MapAllocator,
+ typename VectorAllocator>
+bool ReadG2oFile(const std::string& filename,
+ std::map<int, Pose, std::less<int>, MapAllocator>* poses,
+ std::vector<Constraint, VectorAllocator>* constraints) {
+ CHECK(poses != NULL);
+ CHECK(constraints != NULL);
+
+ poses->clear();
+ constraints->clear();
+
+ std::ifstream infile(filename.c_str());
+ if (!infile) {
+ return false;
+ }
+
+ std::string data_type;
+ while (infile.good()) {
+ // Read whether the type is a node or a constraint.
+ infile >> data_type;
+ if (data_type == Pose::name()) {
+ if (!ReadVertex(&infile, poses)) {
+ return false;
+ }
+ } else if (data_type == Constraint::name()) {
+ ReadConstraint(&infile, constraints);
+ } else {
+ LOG(ERROR) << "Unknown data type: " << data_type;
+ return false;
+ }
+
+ // Clear any trailing whitespace from the line.
+ infile >> std::ws;
+ }
+
+ return true;
+}
+
+} // namespace examples
+} // namespace ceres
+
+#endif // EXAMPLES_CERES_READ_G2O_H_