Dynamic structs had a few major issues.
In C++, if the string was the last definition in the schema, attempting to set a string would trigger an assertion. This has been fixed
Setting a string value could truncate the string actually stored in the struct, if the definition was shorter than the string to set.
There was no way to detect if this case occurred. The set string function now returns a bool if the string was fully written or not.
Reading a string that had a value shorter than the schema definition would result in embedded trailing nulls in the string. This would make comparing string equality basically impossible, as those embedded nulls count for the length of the string.
The above truncating didn't take into account UTF8 code points. This means a truncation could happen in the middle of a unicode character. Depending on the language this had different behavior, but unpaired code points are problematic to detect in any case. On the decoding side, detect if a split UTF8 code point has occurred by the writer, and if so just ignore it and treat it as not part of the string. Doing this on the receive side means a newer receive side is all that is needed to fix this, which is generally a better option then requiring all senders to update.
Actual DynamicStruct instances have 0 units tests for them. Added a bunch of unit tests around strings to ensure things work properly.
This adds support for two serialization formats for complex data types:
- Protobuf for complex objects with variable length internals that need forward and backward wire compatibility (lower speed, more flexible)
- Raw struct (ByteBuffer-style) for fixed-length objects (higher speed, less flexible)
Deserialization can be done either by creating a new object (for immutable objects) or overwriting the contents of an existing object (for mutable objects).
Implementing classes should provide inner classes that implement the Protobuf or Struct interface (in Java) or specialize the wpi::Protobuf or wpi::Struct struct (in C++). It is possible for classes to implement both. If the class itself does not implement serialization, it's possible for third parties/users to provide an implementation instead.
Uses the Google protobuf implementation for C++ and the QuickBuffers alternative protobuf implementation for Java.
The following source code changes were required:
* Whitespace changes from spotless
* PMD warning suppressions for utility class tests
* PMD warning rename from "BeanMembersShouldSerialize" to
"NonSerializableClass"
* Declared more class members as final
- Add InterpolatedTreeMap for Java from team 254's 2016 MIT licensed code
- Add InterpolatedMap for C++ from team 3512's code with @calcmogul (original author) permission
Co-authored-by: Tyler Veness <calcmogul@gmail.com>
Some valid warnings like throwing NullPointerException or using a for
loop instead of System.arraycopy() were fixed.
Abstract classes marked with PMD.AbstractClassWithoutAbstractMethod were
made concrete because they already had protected constructors.
Fixes#1697.
The wpimath library is a new library designed to separate the reusable math functionality
from the common utility library (wpiutil) and the hardware-dependent library (wpilibc/j).
Package names / include file names were NOT changed to minimize breakage. In a future year
it would be good to revamp these for a more uniform user experience and to reduce the risk
of accidental naming conflicts.
While theoretically all of this functionality could be placed into wpiutil, several pieces
of this library (e.g. DARE) are very time-consuming to compile, so it's nice to avoid this
expense for users who only want cscore or ntcore. It also allows for easy future separation
of build tasks vs number of workers on memory-constrained machines.
This moves the following functionality from wpiutil into wpimath:
- Eigen
- ejml
- Drake
- DARE
- wpiutil.math package (Matrix etc)
- units
And the following functionality from wpilibc/j into wpimath:
- Geometry
- Kinematics
- Spline
- Trajectory
- LinearFilter
- MedianFilter
- Feed-forward controllers
Drake is a collection of tools for analyzing robot dynamics and building control systems.
See https://drake.mit.edu/ for details.
Co-authored-by: Tyler Veness <calcmogul@gmail.com>
This adds a wrapper over EJML's SimpleMatrix that uses generated classes representing numbers to encode the dimensions of each matrix at compile time, and to check operations between matrices for validity at compile time, rather than failing with an exception at runtime. This is required for the Java implementation of state-space control.
Additions to the wpiutil gradle script, and a python script at the wpiutil root are used to generate numeric types from a template at build time for both gradle and cmake. Users will be able to access types through functions on the Nat class.
