The library installation involves three easy (famous last words) steps.
Install SR Research EyeLink Developers Kit
This package relies on edfapi library that is as part of the
EyeLink Developers Kit. Therefore, read_edf()
function will not work without it but you will still be
able to use utility functions. The EyeLink Developers Kit can
be downloaded from sr-support.com website. Note that
you need to register and wait for your account to be activated. Next,
follow instructions to install EyeLink Developers Kit for your
platform. The forum thread should be under SR Support Forum ›
Downloads › EyeLink Developers Kit / API › Download: EyeLink Developers
Kit / API Downloads (Windows, macOS, Linux).
Configure R environment variables
The package needs to configure compiler flags for its dependency on EDF API library. Specifically, it needs to specify paths to include header files ( edf.h, edf_data.h, and edftypes.h) and to the library itself. The package will try to compile using sensible defaults for each platform, i.e., default installation paths for EyeLink Developers Kit v2.1.1. However, these defaults may change in the future or you may wish to install the library to a non-standard location (relevant primarily for Windows).
If compilation with default paths fails, you need to define R
environment variables as described below. These variables must be
defined either in user or project .Renviron
file. The simplest way to edit it is via usethis library and edit_r_environ()
function. Type usethis::edit_r_environ()
for user and
usethis::edit_r_environ('project')
for projects
environments (note that the latter shadows the former, read documentation for details). In the
case of Windows, note that you do not need to worry about forward
vs. backward slashes as R will normalize strings for you. Once you
define the variables, restart session and check them by typing
Sys.getenv()
(to see all variables) or
Sys.getenv("EDFAPI_INC")
to check a specific one.
Windows
Default values assume that the EyeLink Developers Kit is installed in
c:/Program Files (x86)/SR Research/EyeLink
(default
installation path).
-
EDFAPI_LIB
: path toedfapi.dll
for 32-bit systems. Defaults toc:/Program Files (x86)/SR Research/EyeLink/libs
. -
EDFAPI_LIB64
(optional): path toedfapi64.dll
for 64-bit systems. By default, the 64-bit library is in x64 subfolder, i.e.,c:/Program Files (x86)/SR Research/EyeLink/libs/x64
. This variable is optional, as the package will try to guess this by itself by appending/x64
toEDFAPI_LIB
path. However, you should specify this variable explicitly if 64-libraries are in a non-standard folder (or SR Research changed it, or you just want to be sure). -
EDFAPI_INC
: path to C header files necessary for compilation. Specifically, the package requires edf.h, edf_data.h, and edftypes.h. Defaults toc:/Program Files (x86)/SR Research/EyeLink/Includes/eyelink
.
Your .Renviron
file include lines similar to the ones
below
EDFAPI_LIB="c:/Program Files (x86)/SR Research/EyeLink/libs"
EDFAPI_LIB64="c:/Program Files (x86)/SR Research/EyeLink/libs/x64"
EDFAPI_INC="c:/Program Files (x86)/SR Research/EyeLink/Includes/eyelink"
Linux
-
EDFAPI_INC
: path to C header files necessary for compilation. Specifically, the package requires edf.h, edf_data.h, and edftypes.h. Defaults to/usr/include/EyeLink
.
Your .Renviron
file should include a line like this
EDFAPI_INC="/usr/include/EyeLink"
Mac OS
-
EDFAPI_LIB
: path to EDF API framework. Defaults to/Library/Frameworks
-
EDFAPI_INC
: path to C header files necessary for compilation. Specifically, the package requires edf.h, edf_data.h, and edftypes.h. Defaults to/Library/Frameworks/edfapi.framework/Headers
Your .Renviron
file include lines similar to the ones
below
EDFAPI_LIB="/Library/Frameworks"
EDFAPI_INC="/Library/Frameworks/edfapi.framework/Headers"
Install the library
To install from github
library("devtools")
install_github("alexander-pastukhov/eyelinkReader", dependencies=TRUE, build_vignettes = TRUE)