0
+ − 1 \name{dynport}
+ − 2 \alias{dynport}
+ − 3 \alias{loadDynportNamespace}
+ − 4 \title{Dynamic R Bindings to standard and common C libraries}
+ − 5 \description{Function to bind APIs of standard and common C libraries to R via dynamically created interface environment objects
+ − 6 comprising R wrappers for C functions, object-like macros, enums and data types.
+ − 7 }
+ − 8 \usage{
+ − 9 dynport(portname, portfile=NULL,
+ − 10 repo=system.file("dynports",package="rdyncall") )
+ − 11 }
+ − 12 \arguments{
+ − 13 \item{portname}{the name of a dynport, given as a literal or character string.}
+ − 14 \item{portfile}{\code{NULL} or character string giving a script file to parse ; \code{portname} and \code{repo} are .}
+ − 15 \item{repo}{character string giving the path to the root of the \emph{dynport} repository.}
+ − 16 }
+ − 17 \details{
+ − 18 \code{dynport} offers a convenient method for binding entire C libraries to R.
+ − 19 This mechanism runs cross-platform and uses dynamic linkage but it implies
+ − 20 that the run-time library of a choosen binding need to be preinstalled in the system.
+ − 21 Depending on the OS, the run-time libraries may be preinstalled or require manual installation.
+ − 22 See \link{rdyncall-demos} for OS-specific installation notes for several C libraries.
+ − 23
+ − 24 The binding method is data-driven using platform-portable specifications named \emph{DynPort} files.
+ − 25 DynPort files are stored in a repository that is installed as part of the package installation.
+ − 26 When \code{dynport} processes a \emph{DynPort} file given by \code{portname},
+ − 27 an environment object is created, populated with R wrapper and helper objects
+ − 28 that make up the interface to the C library, and attached to the search path with the name \code{dynport:<PORTNAME>}.
+ − 29 Unloading of previously loaded dynport environments is achieved via \code{detach(dynport:<PORTNAME>)}.
+ − 30
+ − 31 Up to \pkg{rdyncall} version 0.7.4, R name space objects were used as containers as described in the article \emph{Foreign Library Interface}, thus
+ − 32 dynport \sQuote{packages} appeared as \code{"package:<PORTNAME>"} on the search path. The mechanism to create synthesized R packages at run-time
+ − 33 required the use of \code{.Internal} calls.
+ − 34 But since the use of internal R functions is not permitted for packages distributed on CRAN we downgraded the package to use ordinary environment
+ − 35 objects starting with version 0.7.5 until a public interface for the creation of R namespace objects is available.
+ − 36
+ − 37 The following gives a list of currently available \emph{DynPorts}:
+ − 38 \tabular{ll}{
+ − 39 \strong{DynPort name/C Library} \tab \strong{Description} \cr
+ − 40 \code{expat} \tab Expat XML Parser Library \cr
+ − 41 \code{GL} \tab OpenGL 1.1 API \cr
+ − 42 \code{GLU} \tab OpenGL Utility Library \cr
+ − 43 \code{GLUT} \tab OpenGL Utility Toolkit Library \cr
+ − 44 \code{SDL} \tab Simple DirectMedia Layer library \cr
+ − 45 \code{SDL_image} \tab Loading of image files (png,jpeg..) \cr
+ − 46 \code{SDL_mixer} \tab Loading/Playing of ogg/mp3/mod music files. \cr
+ − 47 \code{SDL_ttf} \tab Loading/Rendering of True Type Fonts. \cr
+ − 48 \code{SDL_net} \tab Networking library. \cr
+ − 49 \code{glew} \tab OpenGL Extension Wrangler (includes OpenGL 3.0) \cr
+ − 50 \code{glfw} \tab OpenGL Windowing/Setup Library \cr
+ − 51 \code{gl3} \tab strict OpenGL 3 (untested) \cr
+ − 52 \code{R} \tab R shared library \cr
+ − 53 \code{ode} \tab Open Dynamics (Physics-) Engine (untested) \cr
+ − 54 \code{cuda} \tab NVIDIA Cuda (untested) \cr
+ − 55 \code{csound} \tab Sound programming language and library \cr
+ − 56 \code{opencl} \tab OpenCL (untested) \cr
+ − 57 \code{stdio} \tab C Standard Library I/O Functions \cr
+ − 58 \code{glpk} \tab GNU Linear Programming Kit \cr
+ − 59 \code{EGL} \tab Embedded Systems Graphics Library \cr
+ − 60 }
+ − 61
+ − 62 As of the current implementation \emph{DynPort} files are R scripts
+ − 63 that perform up to three tasks:
+ − 64
+ − 65 \itemize{
+ − 66 \item Functions (and pointer-to-function variables) are mapped via \code{\link{dynbind}} and a description of the C library using a \emph{library signatures}.
+ − 67 \item Symbolic names are assigned to its values for object-like macro defines and C enum types.
+ − 68 \item Run-time type-information objects for aggregate C data types (struct and union) are registered via \code{\link{parseStructInfos}} and \code{\link{parseUnionInfos}}.
+ − 69 }
+ − 70
+ − 71 The file path to the \emph{DynPort} file is derived from
+ − 72 \code{portname} per default. This would refer to \code{"<repo>/<portname>.R"}
+ − 73 where \code{repo} usually refers to the initial \emph{DynPort} repository
+ − 74 located at the sub-folder \code{"dynports/"} of the package.
+ − 75 If \code{portfile} is given, then this value is taken as file path (usually
+ − 76 for testing purpose).
+ − 77
+ − 78 A tool suite, comprising AWK (was boost wave), GCC Preprocessor, GCC-XML and XSLT, was used to generate the available \emph{DynPort} files automatically
+ − 79 by extracting type information from C library header files.
+ − 80
+ − 81 In a future release, the DynPort format will be changed to
+ − 82 a language-neutral text file document. For the interested reader:
+ − 83 A first prototyp is currently available in an FFI extension to the Lua
+ − 84 programming language (see \code{luadyncall} subversion sub-tree).
+ − 85 A third revision (including function types in call signatures, bitfields, arrays, etc..)
+ − 86 is currently in development.
+ − 87 }
+ − 88 \references{
+ − 89 Adler, D. (2012) \dQuote{Foreign Library Interface}, \emph{The R Journal}, \bold{4(1)}, 30--40, June 2012.
+ − 90 \url{http://journal.r-project.org/archive/2012-1/RJournal_2012-1_Adler.pdf}
+ − 91
+ − 92 Adler, D., Philipp, T. (2008) \emph{DynCall Project}. \url{http://dyncall.org}
+ − 93
+ − 94 Clark, J. (1998). expat - XML Parser Toolkit. \url{http://expat.sourceforge.net}
+ − 95
+ − 96 Ikits, M. and Magallon, M. (2002). The OpenGL Extension Wrangler Library. \url{http://glew.sourceforge.net}
+ − 97
+ − 98 Latinga, S. (1998). The Simple DirectMedia Layer Library. \url{http://www.libsdl.org}
+ − 99
+ − 100 Segal, M. and Akeley, K. (1992). The OpenGL Graphics System. A Specification, Version 1.0. \url{http://www.opengl.org}
+ − 101
+ − 102 Smith, R. (2001). Open Dynamics Engine. \url{http://www.ode.org}
+ − 103 }
+ − 104 \examples{
+ − 105 \donttest{
+ − 106 # Using SDL and OpenGL in R
+ − 107 dynport(SDL)
+ − 108 dynport(GL)
+ − 109 # Initialize Video Sub-system
+ − 110 SDL_Init(SDL_INIT_VIDEO)
+ − 111 # Initialize Screen with OpenGL Context and Double Buffering
+ − 112 SDL_SetVideoMode(320,256,32,SDL_OPENGL+SDL_DOUBLEBUF)
+ − 113 # Clear Color and Clear Screen
+ − 114 glClearColor(0,0,1,0) # blue
+ − 115 glClear(GL_COLOR_BUFFER_BIT)
+ − 116 # Flip Double-Buffer
+ − 117 SDL_GL_SwapBuffers()
+ − 118 }
+ − 119 }
+ − 120 \keyword{programming}
+ − 121 \keyword{interface}
+ − 122