62 lines
4.1 KiB
Plaintext
62 lines
4.1 KiB
Plaintext
This directory will contain headers for the various types of
|
|
KiCad dynamic plugins and associated APIs.
|
|
|
|
In a typical implementation a dynamic plugin will provide a simple interface to
|
|
provide KiCad with a list of functions which can be invoked to provide the
|
|
desired feature. For example the 3D plugins provide a function to list the
|
|
file types supported by the plugin, the associated filters required for browsing
|
|
files, and a Load() function to process a 3D file and return a data structure
|
|
which KiCad can use in the 3D rendering process. The set of functions provided
|
|
by a plugin shall be referred to here as the Plugin Interface. Every plugin
|
|
must be a derived class of at least one type of plugin declared in the header
|
|
files in this directory. All implementations of a plugin interface constitute
|
|
an actual plugin; the various KiCad tools such as pcbnew and eeschema contain
|
|
no actual implementation of the plugin interface.
|
|
|
|
Plugins also need to interact with KiCad and its internal data while knowing
|
|
essentially nothing of the complex structures within KiCad. To make this possible
|
|
each type of dynamic plugin must interact with at least one type of API which
|
|
provides functions to create, inspect, and manipulate the complex data structures
|
|
within KiCad. These APIs shall be declared in the api subdirectory and must be
|
|
implemented within each KiCad tool which services the related plugin type. For
|
|
example the 3D plugins must produce the intermediate scene graph data for use
|
|
by the 3D renderer; to accomplish this an API is required to provide each 3D
|
|
plugin with a method for creating the data structures required by pcbnew and
|
|
cvpcb. In the implementation detail the API may be implemented once in the common
|
|
static library of pcbnew or it can be implemented as a runtime shared library
|
|
which can then be linked to by pcbnew. cvpcb, or even eeschema.
|
|
|
|
Plugin specialization: To keep APIs and plugin interfaces as simple as possible
|
|
it is necessary for plugins to be specialized (have different types). While it
|
|
is possible to define only one plugin interface and one API for any and all
|
|
plugins to use, this would result in a very large API which is difficult to
|
|
maintain. Having specialized plugins and APIs ensures better maintainability
|
|
of the code; a specific plugin may implement multiple plugin interfaces or
|
|
interact with multiple APIs if it makes sense to do so. At least two plugin
|
|
interfaces have been identified for implementation at this point: the 3D
|
|
Plugin Interface and the PCBExport interface. The 3D Plugin Interface shall
|
|
provide a method for processing supported 3D model types and returning an
|
|
intermediate scene graph representation which a renderer can use to create a
|
|
visual representation of the model. The PCBExport interface shall provide a
|
|
means of exporting PCB data to a variety of formats such as Specctra DSN for
|
|
the consumption of autorouters, GenCAD, VRML for visualization of the board
|
|
using external tools, and IDF and IGES for interacting with mechanical designers
|
|
and MCAD software. Other exporters such as netlist exporters or even BoM
|
|
exporters should be possible. A PCBImport Interface is also a possibility but
|
|
is currently a low priority item since there are currently only two import
|
|
functions implemented (Specctra result import and DXF import) and a significant
|
|
amount of work is required to implement the PCBImport API.
|
|
|
|
Plugin management: Since plugins are specialized, each type should also be
|
|
loaded and managed by a specialized plugin manager which has responsibilities
|
|
for ensuring integration of the plugin with KiCad. For example the
|
|
3d_plugin_manager searches a list of paths to identify and load plugins which
|
|
implement the 3D Plugin Interface. The 3D manager extracts information from
|
|
each 3D plugin such as the types of 3D formats supported and the associated
|
|
file extensions; the manager also responds to a Load() request by activating
|
|
the appropriate 3D plugin and executing that plugin's Load() function. In the
|
|
case of the Export Plugin Interface, a specific exporter would enumerate the
|
|
plugins, add a menu item to the File->Export list, load and invoke a plugin's
|
|
Export() function at the user's request, and unload the plugin when the
|
|
Export() function completes.
|