To set the library up on your computer, you need to configure and compile the code. As explained in more detail below, this involves typing:
./configure; make clean all test install env
at the shell prompt. Press the <return> key to execute the commands. The semicolon ; allows us to put multiple commands on the same line. We could otherwise type them on seperate lines.
To configure this library on your computer, in a unix shell type:
./configure
Press the <return> key to execute the command. The configure script sets up the environment for your computer. The reason we type ./ in front of it, it to tell the unix interpreter that the script configure is in the current working directory which is indicated by .. It does this by testing that various options work on your particular setup. The range of options we have should work with most *nix setups. Specifically, configure sets variables from config.in:
set CCS = ("gcc" "cc")
set CFLAGSS = ("-I." "-fPIC")
set DYNS = ("ld -G" "libtool -L.. -lc -dynamic -undefined dynamic_lookup")
set MAKES = ("gmake" "make")
set OPTS = ("-g")
# specify a temporary directory
set TMP = /tmp
These are the options considered in configure. For example, we first try a compiler gcc and if that fails, try cc. We try ther dynamic linker ld -G and if that fails, libtool -L.. -lc -dynamic -undefined dynamic_lookup etc. Note that the configutaion will settle on the first option in the list that passes some internal tests (follow through the script configure).
The configuation the sets e.g. (settings on OS X x86_64):
ARCH = x86_64
OBJ = objects.${ARCH}
BPMS = /Users/plewis/librat
LIB = ${BPMS}/lib
BIN = ${BPMS}/bin
CFLAGS = -I.
MAKE = make
WG = -L -R --create-dirs -o
WGET = /usr/bin/curl
CC = gcc
DYN = libtool -L.. -lc -dynamic -undefined dynamic_lookup
OPT = -g
in the file src/makefile. Note that src/makefile is generate from the template src/Makefile.in.
To compile and test the library (after running ./configure), type:
make clean all test
Press the <return> key to execute the command. In fact, if you forget to run ./configure), this will run it for you, via the file makefile. The command make clean clears out any previously compiled code. Then make all compiles the library ${BPMS}/lib/${ARCH}/libratlib.so (so, you refer to this as -L ${BPMS}/lib/${ARCH} -lratlib. It also compiles a C language interface to the library, ${BPMS}/bin/${ARCH}/RATstart. make test runs a test on the RATstart code, comparing a simple ray tracing outout to a reference one.
To install the library:
make install
You will have generated files in
bin/${ARCH}: executable --RATstartlib/${ARCH}: shared object library --libratlib.so
Notice that these links ⛓ (bin/x86_64, lib/x86_64) don't necessarily exist on the github repository: they are user-generated
Finally, make env runs the script bin/RATsetup.sh and sets appropriate default values for all required BPMS environment variables. These are set in:
~/.bpms_profile: environment
which is sourced from your shell initialisation script (e.g. ~/.bashrc or ~/.zshrc).