fix Makefile, README.md and .gitignore for 2000/rince
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dmy2jd
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rince
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rince
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+301
-186
@@ -1,215 +1,330 @@
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#!/bin/make
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#!/usr/bin/env make
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# 2000 makefile
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#
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#
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# Copyright (C) Simon Cooper, Landon Curt Noll, Peter Seebach
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# IOCCC 2000 winning entry - rince
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# and Leonid A. Broukhis, 2000.
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# All Rights Reserved. Permission for personal, educational or non-profit
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# use is granted provided this this copyright and notice are included in its
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# entirety and remains unaltered. All other uses must receive prior permission
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# from the contest judges.
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SHELL= /bin/sh
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################################################################################
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CAT= cat
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RM= rm
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SED= sed
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TRUE= true
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#CINCLUDE= -I ${HOMEBREW_PREFIX}/include/SDL2
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||||||
# optimization
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||||||
#
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#
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||||||
# Most compiles will safely use -O2. Some can use only -O.
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# Regarding individual entries:
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||||||
# A few compilers have broken optimizers and thus you may
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#
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||||||
# not want anything.
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# IOCCC winning entry code may not work on your system. Even with standards,
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# conditions and build environments change, especially when it comes to more
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||||||
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# extreme code such you might find in an IOCCC winner. Moreover, what was
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# allowed and liked in one IOCCC contest may no longer be liked/allowed in
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# later IOCCC years.
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#
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# Corrections on winning author and fixing typos in remarks are VERY WELCOME.
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#
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# GitHub pull requests are welcome:
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#
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||||||
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# If you have a patch that might make running an entry work in modern Unix-like
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||||||
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# environments, please create a GitHub pull request for the IOCCC judges to
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# consider.
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||||||
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#
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# Suggestions and corrections regarding Makefiles, winning author information,
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# fixing typos in remarks, and code patches are welcome via opening a GitHub
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# issue or better yet, by creating a GitHub pull request for the IOCCC judges
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||||||
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# to consider. To form a GitHub issue or GitHub pull, please visit:
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#
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# https://github.com/ioccc-src/winner
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#
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################################################################################
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# This work by Landon Curt Noll and Leonid A. Broukhis is licensed under:
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#
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# Creative Commons Attribution-ShareAlike 3.0 Unported License.
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#
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# See: http://creativecommons.org/licenses/by-sa/3.0/
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#############################
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# shell used by this Makefile
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#############################
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#
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SHELL= bash
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#######################
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# common tool locations
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#######################
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#
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include ../../var.mk
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# Set X11_LIBDIR to the directory where the X11 library resides
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#
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#X11_LIBDIR= /usr/X11R6/lib
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#X11_LIBDIR= /usr/X11/lib
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X11_LIBDIR= /opt/X11/lib
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# Set X11_INCLUDEDIR to the directory where the X11 include files reside
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#
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#X11_INCDIR= /usr/X11R6/include
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#X11_INCDIR= /usr/X11/include
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X11_INCDIR= /opt/X11/include
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# Common C compiler warnings to silence
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#
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#CSILENCE=
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CSILENCE= -Wno-empty-body -Wno-error -Wno-implicit-function-declaration \
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-Wno-incompatible-pointer-types -Wno-parentheses -Wno-return-type \
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-Wno-unevaluated-expression
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||||||
|
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# Common C compiler warning flags
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||||||
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#
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#CWARN= ${CSILENCE}
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#CWARN= -Wall ${CSILENCE}
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#CWARN= -Wall -Wextra ${CSILENCE}
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CWARN= -Wall -Wextra -pedantic ${CSILENCE}
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# Compiler standard
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#
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#CSTD=
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#CSTD= -ansi
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CSTD= -std=gnu99
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# Compiler bit architecture
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||||||
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#
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# Some entries require 32-bitness:
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# ARCH= -m32
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#
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# Some entries require 64-bitness:
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# ARCH= -m64
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#
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# By default we assume nothing:
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#
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ARCH=
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# Defines that are needed to compile
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#
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#CDEFINE=
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CDEFINE= -DM_PI=3.14159265358979323846
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# Include files that are needed to compile
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#
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#CINCLUDE=
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#CINCLUDE= -include stdlib.h
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#CINCLUDE= -include stdio.h
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#CINCLUDE= -include stdlib.h -include stdio.h
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CINCLUDE= -I ${X11_INCDIR} -I ${X11_INCDIR}/X11
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#CINCLUDE= `${SDL2_CONFIG} --cflags`
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# Optimization
|
||||||
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#
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# Most compiles will safely use -O2. Some can use only -O1 or -O.
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# A few compilers have broken optimizers or this entry make break
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# under those buggy optimizers and thus you may not want anything.
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# Reasonable compilers will allow for -O3.
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#
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#
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#OPT=
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#OPT=
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#OPT= -O
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#OPT= -O
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OPT= -O2
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#OPT= -O1
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#OPT= -O2
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OPT= -O3
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# flags for ANSI compiles
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# Default flags for ANSI C compilation
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#
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#
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# NOTE: Some ANSI compilers make use of -Xa to turn on ANSI mode,
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CFLAGS= ${CSTD} ${CWARN} ${ARCH} ${CDEFINE} ${CINCLUDE} ${OPT}
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# others such as gcc may want -ansi, others (Compaq Tru64 Unix)
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# want -std1, and others may want nothing at all.
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# Adjust the CFLAGS line as needed.
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#
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|
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# NOTE: Some compilers cannot optimize, or optimize some entries
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# incorrectly. You might want to turn on -O to see if your
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# compiler can handle them.
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#
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#
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#CFLAGS= -Xa ${OPT}
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#CFLAGS= -std1 $(OPT)
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CFLAGS= -ansi ${OPT}
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NO_ANSI_CFLAGS=
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# Libraries needed to build
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#NO_ANSI_CFLAGS=
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#
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#LIBS=
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#LIBS= -lm
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LIBS= -lm -L ${X11_LIBDIR} -lX11
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#LIBS= `${SDL2_CONFIG} --libs`
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# NOTE: On some systems, the library path does not include the location
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# C compiler to use
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# of the X11 libraries. You might need to use a -L/path/to/X11/lib/dir
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# in order to compile with these libs.
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#
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X11CCFLAGS= -I/usr/X11R6/include -I/usr/X11R6/include/X11 -I/usr/include/X11
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#X11CCFLAGS=
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X11LDFLAGS= -L/usr/X11R6/lib
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#X11LDFLAGS=
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# Perl
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#
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PERL= perl
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#PERL= perl5
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# ANSI compiler
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#
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# Set CC to the name of your ANSI compiler.
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#
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# Some entries seem to need gcc. If you have gcc, set
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# both CC and MAY_NEED_GCC to gcc.
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#
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||||||
# If you do not have gcc, set CC to the name of your ANSI compiler, and
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# set MAY_NEED_GCC to either ${CC} (and hope for the best) or to just :
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# to disable such programs.
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#
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#
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CC= cc
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CC= cc
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MAY_NEED_GCC= gcc
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#CC=clang
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#CC=gcc
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# winners that compile under ANSI C
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# Compiler add-ons or replacements for clang only
|
||||||
#
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#
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WINNERS= anderson schneiderwent primenum bellard bmeyer briddlebane dhyang \
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ifeq ($(CC),clang)
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dmy2jd jarijyrki dlowe natori rince robison thadgavin tomx
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ALT_NAMES= schneiderwent.orig briddlebane.orig thadgavin.orig
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DATA_FILES= schneiderwent_files bmeyer_files jarijyrki_files
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all: ${WINNERS}
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# Best use of flags
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#
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#
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||||||
anderson: anderson.c
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CSILENCE+= -Wno-comma -Wno-float-conversion -Wno-missing-prototypes \
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${CC} ${CFLAGS} $? -o $@
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-Wno-missing-variable-declarations -Wno-poison-system-directories \
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-Wno-shorten-64-to-32 -Wno-sign-conversion -Wno-strict-prototypes \
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# Most Timely Output
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-Wno-unreachable-code
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#
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#
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schneiderwent: schneiderwent.c
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CWARN+= -Weverything
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${CC} ${CFLAGS} $? -o $@
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||||||
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||||||
schneiderwent_files: schneiderwent.data
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||||||
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||||||
schneiderwent.orig: schneiderwent.orig.c
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${CC} ${CFLAGS} $? -o $@
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||||||
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||||||
# Best Abuse of CPP
|
|
||||||
#
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#
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||||||
primenum: primenum.c
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endif
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${CC} ${CFLAGS} $? -o $@
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||||||
# Most Specific Output
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# Specific add-ons or replacements for gcc only
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||||||
#
|
#
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||||||
bellard: bellard.c
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ifeq ($(CC),gcc)
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${CC} ${CFLAGS} $? -o $@
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#
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||||||
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#CSILENCE+=
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||||||
|
#
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||||||
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#CWARN+=
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||||||
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#
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||||||
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endif
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||||||
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||||||
# Best Utility
|
|
||||||
#
|
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||||||
# machines operating in 64 bit mode:
|
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||||||
#
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||||||
bmeyer: bmeyer.c
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||||||
${CC} -DY= -O6 $? -o $@ -lm
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||||||
#
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||||||
# linux/x86, glibc 2.0, libc4/5:
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||||||
#
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||||||
# bmeyer: bmeyer.c
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||||||
# ${CC} -DY="__setfpucw(0x127f)" -O6 $? -o $@ -lm
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|
||||||
#
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|
||||||
# linux/x86, glibc 2.1:
|
|
||||||
#
|
|
||||||
# bmeyer: bmeyer.c
|
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||||||
# ${MAY_NEED_GCC} -DY='int x=0x127f; __asm__ ("fldcw %0" : : "m" (*&x))' \
|
|
||||||
# -O6 $? -o $@ -lm
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|
|
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bmeyer_files: lavabus.pgm lenna.glic michael.pgm
|
##############################
|
||||||
|
# Special flags for this entry
|
||||||
# Best Abuse of User
|
##############################
|
||||||
#
|
#
|
||||||
briddlebane: briddlebane.c
|
ENTRY= rince
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${CC} ${CFLAGS} $? -o $@ -lm
|
PROG= ${ENTRY}
|
||||||
|
|
||||||
briddlebane.orig: briddlebane.orig.c
|
|
||||||
${CC} ${CFLAGS} $? -o $@ -lm
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|
||||||
|
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||||||
# Best Layout
|
|
||||||
#
|
#
|
||||||
dhyang: dhyang.c
|
OBJ= ${PROG}.o
|
||||||
${CC} ${CFLAGS} $? -o $@
|
DATA=
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||||||
|
TARGET= ${PROG} dmy2jd
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||||||
dmy2jd: dmy2jd.c
|
|
||||||
${CC} ${CFLAGS} $? -o $@
|
|
||||||
|
|
||||||
# Best of Show
|
|
||||||
#
|
#
|
||||||
jarijyrki: jarijyrki.c
|
ALT_OBJ=
|
||||||
${CC} ${X11CCFLAGS} ${CFLAGS} -DNeedFunctionPrototypes \
|
ALT_TARGET=
|
||||||
-DU=40 -DT=98 '-Dz=(T+1)*U*U' -DQ=80 -DS=20 -DN=10 -DB=5 -DG=23 \
|
|
||||||
-Dp=7 '-DM=((p+1)*Q)+S' '-DH=(G*S)+S+S' -DC=XK_Up -DL=XK_Down \
|
|
||||||
-DO=XK_Left -DV=XK_Right -DR=XK_Escape -D_=XK_BackSpace \
|
|
||||||
$? -o $@ ${X11LDFLAGS} -lX11
|
|
||||||
|
|
||||||
jarijyrki_files: sheet1.info
|
|
||||||
|
|
||||||
# Worst Abuse of the Rules
|
#################
|
||||||
|
# build the entry
|
||||||
|
#################
|
||||||
#
|
#
|
||||||
# NOTE: You will need to adjust this path to the place where Perl has been
|
all: data ${TARGET}
|
||||||
# installed on your system. Running "perl -V" may help you locate
|
|
||||||
# this place.
|
|
||||||
#
|
|
||||||
# The following bit of perl may help determining the values you need:
|
|
||||||
#
|
|
||||||
# perl -MConfig -e 'print "$Config{archlibexp}/CORE\n"'
|
|
||||||
#
|
|
||||||
#
|
|
||||||
dlowe: dlowe.c
|
|
||||||
${CC} ${NO_ANSI_CFLAGS} -DPERL_POLLUTE \
|
|
||||||
`${PERL} -MExtUtils::Embed -e ccopts` $? -o $@ \
|
|
||||||
`${PERL} -MExtUtils::Embed -e ldopts`
|
|
||||||
|
|
||||||
# Best Small Program
|
|
||||||
#
|
|
||||||
natori: natori.c
|
|
||||||
${CC} ${CFLAGS} $? -o $@ -lm
|
|
||||||
|
|
||||||
# Astronomically Obfuscated
|
|
||||||
#
|
|
||||||
rince: rince.c
|
|
||||||
${CC} ${X11CCFLAGS} ${CFLAGS} -DM_PI=3.14159265358979323846 \
|
|
||||||
$? -o $@ -lm ${X11LDFLAGS} -lX11
|
|
||||||
|
|
||||||
# Best game
|
|
||||||
#
|
|
||||||
robison: robison.c
|
|
||||||
${CC} ${CFLAGS} $? -o $@
|
|
||||||
|
|
||||||
# Most Portable Output
|
|
||||||
#
|
|
||||||
thadgavin: thadgavin.c
|
|
||||||
${CC} ${CFLAGS} $? -o $@ -lcurses -lm
|
|
||||||
|
|
||||||
thadgavin.orig: thadgavin.orig.c
|
|
||||||
${CC} ${CFLAGS} $? -o $@ -lncurses -lm
|
|
||||||
|
|
||||||
# Most Complete Program
|
|
||||||
#
|
|
||||||
tomx: tomx.c
|
|
||||||
${CC} ${CFLAGS} $? -o $@
|
|
||||||
|
|
||||||
everything: ${WINNERS} ${ALT_NAMES} ${DATA_FILES}
|
|
||||||
|
|
||||||
clean:
|
|
||||||
${RM} -f *.o a.out core ${WINNERS}
|
|
||||||
|
|
||||||
clobber: clean
|
|
||||||
${RM} -f ${WINNERS}
|
|
||||||
${RM} -f ${ALT_NAMES}
|
|
||||||
|
|
||||||
nuke: clobber
|
|
||||||
@${TRUE}
|
@${TRUE}
|
||||||
|
|
||||||
install: all
|
.PHONY: all alt data everything clean clobber install \
|
||||||
${CAT} ${WINNERS} ${ALT_NAMES} > /dev/null
|
love haste waste maker easter_egg sandwich \
|
||||||
|
supernova deep_magic magic charon pluto
|
||||||
|
|
||||||
|
${PROG}: ${PROG}.c
|
||||||
|
${CC} ${CFLAGS} $< -o $@ ${LIBS}
|
||||||
|
|
||||||
|
# alternative executable
|
||||||
|
#
|
||||||
|
alt: data ${ALT_TARGET}
|
||||||
|
@${TRUE}
|
||||||
|
|
||||||
|
# data files
|
||||||
|
#
|
||||||
|
data: ${DATA}
|
||||||
|
@${TRUE}
|
||||||
|
|
||||||
|
# both all and alt
|
||||||
|
#
|
||||||
|
everything: all alt
|
||||||
|
|
||||||
|
|
||||||
|
###############
|
||||||
|
# utility rules
|
||||||
|
###############
|
||||||
|
#
|
||||||
|
clean:
|
||||||
|
${RM} -f ${OBJ} ${ALT_OBJ}
|
||||||
|
@-if [ -f indent.c ]; then \
|
||||||
|
echo ${RM} -f indent.c; \
|
||||||
|
${RM} -f indent.c; \
|
||||||
|
fi
|
||||||
|
|
||||||
|
clobber: clean
|
||||||
|
${RM} -f ${TARGET} ${ALT_TARGET}
|
||||||
|
@-if [ -e sandwich ]; then \
|
||||||
|
${RM} -f sandwich; \
|
||||||
|
echo 'ate sandwich'; \
|
||||||
|
fi
|
||||||
|
|
||||||
|
install:
|
||||||
|
@echo "Dr. Spock says that is not logical!"
|
||||||
|
@${TRUE}
|
||||||
|
|
||||||
|
# you may be able to misunderstand the source by reading indent.c
|
||||||
|
#
|
||||||
|
indent.c: ${PROG}.c
|
||||||
|
@if which "${GINDENT}" >/dev/null 2>&1; then \
|
||||||
|
echo ${RM} -f $@; \
|
||||||
|
${RM} -f $@; \
|
||||||
|
echo "${GINDENT} < $< > $@"; \
|
||||||
|
${GINDENT} < $< > $@; \
|
||||||
|
elif which "${INDENT}" >/dev/null 2>&1; then \
|
||||||
|
echo ${RM} -f $@; \
|
||||||
|
${RM} -f $@; \
|
||||||
|
echo "${INDENT} < $< > $@"; \
|
||||||
|
${INDENT} < $< > $@; \
|
||||||
|
else \
|
||||||
|
echo "no intent tool found, ident $< yourself, sorry"; \
|
||||||
|
echo "exit 1"; \
|
||||||
|
exit 1; \
|
||||||
|
fi
|
||||||
|
|
||||||
|
|
||||||
|
##################
|
||||||
|
# 133t hacker rulz
|
||||||
|
##################
|
||||||
|
#
|
||||||
|
love:
|
||||||
|
@echo 'not war?'
|
||||||
|
@${TRUE}
|
||||||
|
|
||||||
|
haste:
|
||||||
|
$(MAKE) waste
|
||||||
|
@${TRUE}
|
||||||
|
|
||||||
|
waste:
|
||||||
|
@echo 'haste'
|
||||||
|
@${TRUE}
|
||||||
|
|
||||||
|
maker:
|
||||||
|
@echo 'Participate in a maker faire'
|
||||||
|
@${TRUE}
|
||||||
|
|
||||||
|
easter_egg:
|
||||||
|
@echo "you expected to often misunderstand this $${RANDOM} magic"
|
||||||
|
@echo "chongo '<was here>' /\\oo/\\"
|
||||||
|
@echo "Eggy"
|
||||||
|
|
||||||
|
sandwich: easter_egg
|
||||||
|
@if [ `id -u` -eq 0 ]; then \
|
||||||
|
echo 'Okay.'; \
|
||||||
|
echo "$${RANDOM}`date +%s`$${RANDOM}" > $@; \
|
||||||
|
else \
|
||||||
|
echo 'What? Make it yourself.'; \
|
||||||
|
exit 1; \
|
||||||
|
fi
|
||||||
|
|
||||||
|
# Understand the history of the Homebrew Computer Club
|
||||||
|
# as well as the West Coast Computer Faire and
|
||||||
|
# you might be confused different. :-)
|
||||||
|
#
|
||||||
|
supernova: sandwich
|
||||||
|
@-if [ -r .code_anal ]; then \
|
||||||
|
${RM} -f .code_anal_v6; \
|
||||||
|
else \
|
||||||
|
echo "planet deniers, like some members of the IAU, are so cute when they try to defend their logic"; \
|
||||||
|
fi
|
||||||
|
@echo "A $@ helps ${MAKE} the elements that help form planets"
|
||||||
|
@${TRUE}
|
||||||
|
|
||||||
|
deep_magic: supernova
|
||||||
|
@-if [ -r .code_anal ]; then \
|
||||||
|
ccode_analysis --deep_magic 7889066cdbdf09b0408021754586e895be641cc9be29e7eafd3ca65359541f17 \
|
||||||
|
--FNV1a_hash_512_bit -v2 "${PROG}" "${PROG}.c"; \
|
||||||
|
else \
|
||||||
|
echo "Wrong! Do it again!"; \
|
||||||
|
sleep 2; \
|
||||||
|
echo "Wrong! Do it again!"; \
|
||||||
|
sleep 2; \
|
||||||
|
echo "Wrong! Do it again!"; \
|
||||||
|
fi
|
||||||
|
@${TRUE}
|
||||||
|
|
||||||
|
magic: deep_magic
|
||||||
|
@-if [ -r .code_anal ]; then \
|
||||||
|
ccode_analysis --level 20003 --mode 5717175 --FNV1a_hash_512_bit -v2 "${PROG}" "${PROG}.c"; \
|
||||||
|
else \
|
||||||
|
echo "If you don't eat yer meat, you can't have any pudding!"; \
|
||||||
|
echo "How can you have any pudding if you don't eat yer meat?!"; \
|
||||||
|
fi
|
||||||
|
@${TRUE}
|
||||||
|
|
||||||
|
# The IOCCC resident astronomer states
|
||||||
|
#
|
||||||
|
charon: magic
|
||||||
|
@echo "$@ is a dwarf planet"
|
||||||
|
@echo "dwarf is a type of planet"
|
||||||
|
@echo "therefore IAU, $@ is a planet"
|
||||||
|
|
||||||
|
pluto: charon
|
||||||
|
${MAKE} charon
|
||||||
|
@echo "$@ is a dwarf planet"
|
||||||
|
@echo "dwarf is a type of planet"
|
||||||
|
@echo "therefore, $@ is a planet"
|
||||||
|
@echo "having lots of planets is good feature because supernovae can help ${MAKE} a lot of them"
|
||||||
+267
-264
@@ -1,333 +1,336 @@
|
|||||||
Astronomically Obfuscated:
|
# Astronomically Obfuscated:
|
||||||
|
|
||||||
James Bonfield
|
James Bonfield
|
||||||
MRC Laboratory of Molcular Biology
|
MRC Laboratory of Molcular Biology
|
||||||
Hills Road,
|
Hills Road,
|
||||||
Cambridge
|
Cambridge
|
||||||
CB2 2QH
|
CB2 2QH
|
||||||
England
|
England
|
||||||
|
|
||||||
|
# To build:
|
||||||
|
|
||||||
Judges' Comments:
|
```sh
|
||||||
|
make
|
||||||
|
```
|
||||||
|
|
||||||
To build:
|
### To run:
|
||||||
|
|
||||||
make rince
|
```sh
|
||||||
|
./rince number number2
|
||||||
|
```
|
||||||
|
|
||||||
To run (using an X windows server):
|
### Try:
|
||||||
|
|
||||||
./rince
|
```sh
|
||||||
|
make dmy2jd
|
||||||
|
./rince 0.001 `./dmy2jd 7.8 1 1610`
|
||||||
|
```
|
||||||
|
|
||||||
Also try:
|
## Judges' comments:
|
||||||
|
|
||||||
make dmy2jd
|
This program may have you going around in circles :-) Try running it
|
||||||
./rince 0.001 `./dmy2jd 7.8 1 1610`
|
first before reading the Selected Author's Comments below.
|
||||||
|
|
||||||
|
The judges verified the correctness of output for recent dates
|
||||||
|
thru visual observation.
|
||||||
|
|
||||||
|
## Author's comments:
|
||||||
|
|
||||||
|
### How to use it
|
||||||
|
|
||||||
|
The simplest way to run it is with no arguments. Just type:
|
||||||
|
|
||||||
|
```sh
|
||||||
|
./rince
|
||||||
|
```
|
||||||
|
|
||||||
|
You will need to have access to X windows, although it doesn't require
|
||||||
|
desperately high resolution and there are no known limitations on colour
|
||||||
|
depth.
|
||||||
|
|
||||||
|
The display will change slowly over time, although it may take 10 minutes
|
||||||
|
or more to be visible. For those that cannot wait that long the program
|
||||||
|
has a built in time machine. Indeed the program knows the speed of light,
|
||||||
|
which is used to ensure that we see the "live" pictures. Simply specify
|
||||||
|
the fraction of a day to skip forward for each screen refresh. I suggest:
|
||||||
|
|
||||||
|
```sh
|
||||||
|
./rince 0.01
|
||||||
|
```
|
||||||
|
|
||||||
|
To display the output (still guessing?) for a given date, specify two
|
||||||
|
arguments. The first argument is as before and the second argument is a
|
||||||
|
Julian day number (given as a fractional component). Eg:
|
||||||
|
|
||||||
|
```sh
|
||||||
|
./rince 0 2441193.6
|
||||||
|
./rince 0.01 2441193.6
|
||||||
|
```
|
||||||
|
|
||||||
|
A Julian day is defined to be the number of days since January 1st in
|
||||||
|
the year -4712 (4713BC), starting at 12 noon GMT.[1] To aid conversion
|
||||||
|
from our time (GMT) to Julian day there is a supplementary program
|
||||||
|
named: dmy2jd.c. Run it with "day_float month year" as arguments. See
|
||||||
|
below for an example.
|
||||||
|
|
||||||
|
### What it does
|
||||||
|
|
||||||
|
This program plots the positions of the four Galilean moons of Jupiter,
|
||||||
|
as seen from earth. It doesn't correct for your location on earth, but I
|
||||||
|
assure you that the parallax is minimal!
|
||||||
|
|
||||||
|
The moons are labelled with roman numerals from I to IV. I being the
|
||||||
|
closest to the planet and IV being the furthest. They are:
|
||||||
|
|
||||||
|
I Io
|
||||||
|
II Europa
|
||||||
|
III Ganymede
|
||||||
|
IV Callisto
|
||||||
|
|
||||||
|
Amazingly, all it takes is a pair of binoculars to see the Galilean moons,
|
||||||
|
so the results can be experimentally checked. (Note that at present, the
|
||||||
|
best views of Jupiter are over the autumn/winter.)
|
||||||
|
|
||||||
This program may have you going around in circles :-) Try running it
|
The positions of the moons should be correct for binoculars, but possibly
|
||||||
first before reading the Selected Author's Comments below.
|
not if you have a telescope or if you are in the southern hemisphere. In
|
||||||
|
that case I suggest that to get the correct image you look at the screen
|
||||||
|
from inside the monitor whilst standing on your head. In case of
|
||||||
|
confusion, please consult the following chart (*):
|
||||||
|
|
||||||
The judges verified the correctness of output for recent dates
|
N
|
||||||
thru visual observation.
|
^
|
||||||
|
|
|
||||||
|
E <---+---> W
|
||||||
|
|
|
||||||
|
v
|
||||||
|
S
|
||||||
|
|
||||||
|
(*) Not to scale.
|
||||||
|
|
||||||
Selected Author's Comments:
|
### History
|
||||||
|
|
||||||
How to use it
|
Galileo discovered the moons in January 1610.
|
||||||
-------------
|
"http://www-isds.jpl.nasa.gov/cwo/cwo_54ga/html/cd/galileo.htm" states
|
||||||
|
the following:
|
||||||
|
|
||||||
The simplest way to run it is with no arguments. Just type:
|
```
|
||||||
|
By early 1610, Galileo had further improved his telescope by
|
||||||
|
double its power, so it now enlarged objects a thousand
|
||||||
|
times. He began looking at the stars and couldn't believe how
|
||||||
|
many more he could now see! The number seemed infinite. He was
|
||||||
|
beginning to realize the fixed stars weren't a flat distant
|
||||||
|
wall on a globe, but a three-dimensional expanse bigger than
|
||||||
|
anyone had ever thought!
|
||||||
|
|
||||||
./rince
|
Then, on January 7, about an hour after sunset, Jupiter rose
|
||||||
|
in the east, and Galileo happened to turn his powerful scope
|
||||||
|
on its bright disk. It wasn't the first time he had looked at
|
||||||
|
Jupiter, but before it was with one of his lesser-powered
|
||||||
|
telescopes. This time, though, he noticed three small but
|
||||||
|
bright stars near the planet, two to one side and one to the
|
||||||
|
other. He wondered at how bright the small stars were and how
|
||||||
|
they were arranged in what seemed like a straight line. The
|
||||||
|
next night he decided to look at Jupiter again, and to his
|
||||||
|
surprise, the stars had moved. But not in such a way as he
|
||||||
|
would expect. If Jupiter was moving as it normally should, the
|
||||||
|
stars would be east of Jupiter. But all three were to the
|
||||||
|
west! The next night was cloudy, but on January 10, Galileo
|
||||||
|
was able to observe the planet again. One of the stars was
|
||||||
|
gone, and the other two were now on the east side. As the
|
||||||
|
stars moved around Jupiter on each succeeding night, and were
|
||||||
|
finally joined by a fourth star, it dawned on Galileo that
|
||||||
|
what he had found were moons orbiting Jupiter! Almost at once
|
||||||
|
he realized that this was proof that not all objects orbited
|
||||||
|
the Earth. Here were four bodies that were orbiting
|
||||||
|
Jupiter. One argument against the sun-centered theory was, if
|
||||||
|
the Earth orbited the sun, wouldn't the moon get left behind?
|
||||||
|
Here he could see for himself that somehow, a planet could
|
||||||
|
orbit the sun, and not leave a moon behind!
|
||||||
|
```
|
||||||
|
|
||||||
You will need to have access to X windows, although it doesn't require
|
Thus we can plot Galileo's discoveries using the following three plots:
|
||||||
desperately high resolution and there are no known limitations on colour
|
|
||||||
depth.
|
|
||||||
|
|
||||||
The display will change slowly over time, although it may take 10 minutes
|
```sh
|
||||||
or more to be visible. For those that cannot wait that long the program
|
./rince 0 `./dmy2jd 7.8 1 1610`
|
||||||
has a built in time machine. Indeed the program knows the speed of light,
|
./rince 0 `./dmy2jd 8.8 1 1610`
|
||||||
which is used to ensure that we see the "live" pictures. Simply specify
|
./rince 0 `./dmy2jd 10.8 1 1610`
|
||||||
the fraction of a day to skip forward for each screen refresh. I suggest:
|
```
|
||||||
|
|
||||||
./rince 0.01
|
However we can go one better by seeing what Galileo would have seen if it
|
||||||
|
wasn't cloudy on the 9th. Try "./rince 0 `./dmy2jd 9.85 1 1610`" to see
|
||||||
|
what he was missing out on. I wonder what he'd have made of that!
|
||||||
|
|
||||||
To display the output (still guessing?) for a given date, specify two
|
Galileo discovered the fourth moon a few days later.
|
||||||
arguments. The first argument is as before and the second argument is a
|
|
||||||
Julian day number (given as a fractional component). Eg:
|
|
||||||
|
|
||||||
./rince 0 2441193.6
|
I've tried typing these dates in to two Java based Jovian moon plotters,
|
||||||
./rince 0.01 2441193.6
|
but both I tried had problems dealing with dates earlier than 1900. More
|
||||||
|
professional software, such as the SkyMap program [3] gets these values
|
||||||
|
correct and this compares well with the above description and with this
|
||||||
|
IOCCC entry.
|
||||||
|
|
||||||
A Julian day is defined to be the number of days since January 1st in
|
|
||||||
the year -4712 (4713BC), starting at 12 noon GMT.[1] To aid conversion
|
|
||||||
from our time (GMT) to Julian day there is a supplementary program
|
|
||||||
named: dmy2jd.c. Run it with "day_float month year" as arguments. See
|
|
||||||
below for an example.
|
|
||||||
|
|
||||||
|
The year 4713BC was chosen by Joseph Justus Scaliger in the 16th Century,
|
||||||
|
so clearly this program has a long history :-) A more complete description
|
||||||
|
of the origins of Julian Days can be found at:
|
||||||
|
|
||||||
What it does
|
http://aa.usno.navy.mil/AA/faq/docs/millennium.html
|
||||||
------------
|
|
||||||
|
|
||||||
This program plots the positions of the four Galilean moons of Jupiter,
|
### Assumptions
|
||||||
as seen from earth. It doesn't correct for your location on earth, but I
|
|
||||||
assure you that the parallax is minimal!
|
|
||||||
|
|
||||||
The moons are labelled with roman numerals from I to IV. I being the
|
1. The ASCII character set is used.
|
||||||
closest to the planet and IV being the furthest. They are:
|
|
||||||
|
|
||||||
I Io
|
2. That an enormous comet hasn't changed the course of Jupiter (or Earth!).
|
||||||
II Europa
|
|
||||||
III Ganymede
|
3. That the date has not been specified as the gap between the Julian and Gregorian calendar.
|
||||||
IV Callisto
|
|
||||||
|
4. That the DISPLAY environment variable is set and the X display can opened. If this is not the case the program will crash.
|
||||||
|
|
||||||
|
5. There is a year 2000BC problem :-)
|
||||||
|
|
||||||
Amazingly, all it takes is a pair of binoculars to see the Galilean moons,
|
More specifically, the plots for dates that far back are too inaccurate
|
||||||
so the results can be experimentally checked. (Note that at present, the
|
to be of realistic use. Comparisons against SkyMap Pro [3] show that
|
||||||
best views of Jupiter are over the autumn/winter.)
|
there is a good similarity (but not much more) up to about 500BC.
|
||||||
|
|
||||||
The positions of the moons should be correct for binoculars, but possibly
|
6. The code definitely is not portable - it will produce incorrect results if run from the surface of Mars.
|
||||||
not if you have a telescope or if you are in the southern hemisphere. In
|
|
||||||
that case I suggest that to get the correct image you look at the screen
|
|
||||||
from inside the monitor whilst standing on your head. In case of
|
|
||||||
confusion, please consult the following chart (*):
|
|
||||||
|
|
||||||
N
|
### Obfuscations
|
||||||
^
|
|
||||||
|
|
|
||||||
E <---+---> W
|
|
||||||
|
|
|
||||||
v
|
|
||||||
S
|
|
||||||
|
|
||||||
(*) Not to scale.
|
In addition to the normal obfuscations, I feel that the code contains
|
||||||
|
some less common tricks. Taken through the standard rounds listed in the
|
||||||
|
guidelines, the code attempts to pass these as follows:
|
||||||
|
|
||||||
|
1. Look at the original source
|
||||||
|
|
||||||
History
|
With luck, pure casual inspection should not reveal much except
|
||||||
-------
|
that the program contains the X Windows logo (a big clue) and
|
||||||
|
contains a date. This date may give a clue to a few people that
|
||||||
|
this is an astronomical program.
|
||||||
|
|
||||||
Galileo discovered the moons in January 1610.
|
Unfortunately I was stretched for space which meant that the
|
||||||
"http://www-isds.jpl.nasa.gov/cwo/cwo_54ga/html/cd/galileo.htm" states
|
large string constant could not be split up using a "partA"
|
||||||
the following:
|
"partB" method which clearly limits the code layout. However the
|
||||||
|
space saved by using a single long string constant is more than
|
||||||
|
outweighed by ability to further obfuscate.
|
||||||
|
|
||||||
By early 1610, Galileo had further improved his telescope by
|
2. convert ANSI tri-graphs to ASCII
|
||||||
double its power, so it now enlarged objects a thousand
|
|
||||||
times. He began looking at the stars and couldn't believe how
|
|
||||||
many more he could now see! The number seemed infinite. He was
|
|
||||||
beginning to realize the fixed stars weren't a flat distant
|
|
||||||
wall on a globe, but a three-dimensional expanse bigger than
|
|
||||||
anyone had ever thought!
|
|
||||||
|
|
||||||
Then, on January 7, about an hour after sunset, Jupiter rose
|
These are not used.
|
||||||
in the east, and Galileo happened to turn his powerful scope
|
|
||||||
on its bright disk. It wasn't the first time he had looked at
|
|
||||||
Jupiter, but before it was with one of his lesser-powered
|
|
||||||
telescopes. This time, though, he noticed three small but
|
|
||||||
bright stars near the planet, two to one side and one to the
|
|
||||||
other. He wondered at how bright the small stars were and how
|
|
||||||
they were arranged in what seemed like a straight line. The
|
|
||||||
next night he decided to look at Jupiter again, and to his
|
|
||||||
surprise, the stars had moved. But not in such a way as he
|
|
||||||
would expect. If Jupiter was moving as it normally should, the
|
|
||||||
stars would be east of Jupiter. But all three were to the
|
|
||||||
west! The next night was cloudy, but on January 10, Galileo
|
|
||||||
was able to observe the planet again. One of the stars was
|
|
||||||
gone, and the other two were now on the east side. As the
|
|
||||||
stars moved around Jupiter on each succeeding night, and were
|
|
||||||
finally joined by a fourth star, it dawned on Galileo that
|
|
||||||
what he had found were moons orbiting Jupiter! Almost at once
|
|
||||||
he realized that this was proof that not all objects orbited
|
|
||||||
the Earth. Here were four bodies that were orbiting
|
|
||||||
Jupiter. One argument against the sun-centered theory was, if
|
|
||||||
the Earth orbited the sun, wouldn't the moon get left behind?
|
|
||||||
Here he could see for himself that somehow, a planet could
|
|
||||||
orbit the sun, and not leave a moon behind!
|
|
||||||
|
|
||||||
Thus we can plot Galileo's discoveries using the following three plots:
|
3. C pre-process the source ignoring #include lines
|
||||||
|
4. C pre-process the source ignoring #define and #include lines
|
||||||
|
|
||||||
./rince 0 `./dmy2jd 7.8 1 1610`
|
This does a good job of expanding out the code, but it does not
|
||||||
./rince 0 `./dmy2jd 8.8 1 1610`
|
clarify things greatly. The use of #defines has been restricted
|
||||||
./rince 0 `./dmy2jd 10.8 1 1610`
|
primarily to a space-saving mechanism.
|
||||||
|
|
||||||
However we can go one better by seeing what Galileo would have seen if it
|
Additionally, the use of typedefs means that the types used are
|
||||||
wasn't cloudy on the 9th. Try "./rince 0 `./dmy2jd 9.85 1 1610`" to see
|
still obscured unless further replacement edits are made.
|
||||||
what he was missing out on. I wonder what he'd have made of that!
|
|
||||||
|
|
||||||
Galileo discovered the fourth moon a few days later.
|
5. Run it through a C beautifier.
|
||||||
|
|
||||||
I've tried typing these dates in to two Java based Jovian moon plotters,
|
GNU indent seems to do a reasonable job, provided that the
|
||||||
but both I tried had problems dealing with dates earlier than 1900. More
|
#defines are expanded first. This doesn't lay the algorithm
|
||||||
professional software, such as the SkyMap program [3] gets these values
|
particularly bare though as most of the obfuscations are not
|
||||||
correct and this compares well with the above description and with this
|
simple code layouts.
|
||||||
IOCCC entry.
|
|
||||||
|
|
||||||
|
6. Examine the algorithm.
|
||||||
|
|
||||||
The year 4713BC was chosen by Joseph Justus Scaliger in the 16th Century,
|
The algorithm operates on two levels. The main visible level is
|
||||||
so clearly this program has a long history :-) A more complete description
|
by taking a large string and breaking this down into a series of
|
||||||
of the origins of Julian Days can be found at:
|
op-codes (which I have termed J-code). These are then executed.
|
||||||
|
|
||||||
http://aa.usno.navy.mil/AA/faq/docs/millennium.html
|
To get to the real method of how it works, you need to decode
|
||||||
|
the op-code string (which deliberately contains as many ; { and
|
||||||
|
} symbols as possible), which will give you a reverse-polish
|
||||||
|
notation chunk of mathematics.
|
||||||
|
|
||||||
|
Sensible people amongst you will simply refer to the referenced
|
||||||
|
book :-)
|
||||||
|
|
||||||
Assumptions
|
7. Lint it.
|
||||||
-----------
|
|
||||||
|
|
||||||
1. The ASCII character set is used.
|
I no longer have lint, although I do have access to Purify. I'm
|
||||||
|
happy to say that purify does not detect any memory errors or
|
||||||
|
memory leaks.
|
||||||
|
|
||||||
2. That an enormous comet hasn't changed the course of Jupiter (or Earth!).
|
See below for compilation warnings.
|
||||||
|
|
||||||
3. That the date has not been specified as the gap between the Julian
|
8. Compile it.
|
||||||
and Gregorian calendar.
|
|
||||||
|
|
||||||
4. That the DISPLAY environment variable is set and the X display can
|
I'm sorry to say that there are several warnings issued by the
|
||||||
opened. If this is not the case the program will crash.
|
compiler.
|
||||||
|
|
||||||
5. There is a year 2000BC problem :-)
|
Firstly, the return type for X() is not specified, so it
|
||||||
More specifically, the plots for dates that far back are too inaccurate
|
defaults to int. Horror of all horrors - this function does not
|
||||||
to be of realistic use. Comparisons against SkyMap Pro [3] show that
|
return an integer type (it doesn't contain any specific
|
||||||
there is a good similarity (but not much more) up to about 500BC.
|
returns). The return value from X() is not accessed. The same
|
||||||
|
problem occurs in main - it does not return. However main never
|
||||||
|
exits unless there is a serious error.
|
||||||
|
|
||||||
6. The code definitely is not portable - it will produce incorrect results
|
The 6th argument of XDrawText (which should be XTextItem) is
|
||||||
if run from the surface of Mars.
|
passed as a compatible structure, but without casting. This is
|
||||||
|
to reduce code space. A more elegant solution is to remove the
|
||||||
|
"struct {...} Z" completely and use "XTextItem
|
||||||
|
f={i-127+r/3*2,r%3+r/3+1,0,E}" at the start of XDrawText
|
||||||
|
block. Although this is accepted by several compilers, it is not
|
||||||
|
strict ANSI due to the non-constant initialisers. A pity.
|
||||||
|
|
||||||
|
Note that I make use of usleep(). This is a POSIX call (it is
|
||||||
|
BSD), but it supported on many systems. It may be implemented
|
||||||
|
using select() or poll() if required, or as a final solution you
|
||||||
|
may change the usleep(10000) to sleep(1). To compile on systems
|
||||||
|
which do not have usleep, but do have select, the following may
|
||||||
|
suffice as an additional compiler argument:
|
||||||
|
|
||||||
Obfuscations
|
```sh
|
||||||
------------
|
-Dusleep={time_t v[2]={0,10000};select(0,0,0,0,v);}
|
||||||
|
```
|
||||||
|
|
||||||
In addition to the normal obfuscations, I feel that the code contains
|
Gcc complains about "unreachable code at beginning of switch
|
||||||
some less common tricks. Taken through the standard rounds listed in the
|
statement", although removing some of this code will prevent
|
||||||
guidelines, the code attempts to pass these as follows:
|
the algorithm from working.
|
||||||
|
|
||||||
1. Look at the original source
|
Gcc also suggests that I should be using extra parenthesis, but
|
||||||
|
I'm taking this as good comment :-)
|
||||||
|
|
||||||
With luck, pure casual inspection should not reveal much except
|
|
||||||
that the program contains the X Windows logo (a big clue) and
|
|
||||||
contains a date. This date may give a clue to a few people that
|
|
||||||
this is an astronomical program.
|
|
||||||
|
|
||||||
Unfortunately I was stretched for space which meant that the
|
In addition to the above, the program has the following useful(?)
|
||||||
large string constant could not be split up using a "partA"
|
obfuscations:
|
||||||
"partB" method which clearly limits the code layout. However the
|
|
||||||
space saved by using a single long string constant is more than
|
|
||||||
outweighed by ability to further obfuscate.
|
|
||||||
|
|
||||||
2. convert ANSI tri-graphs to ASCII
|
1. The algorithm requires many floating point numbers (about
|
||||||
|
50). These are encoded as ASCII.
|
||||||
|
|
||||||
These are not used.
|
2. The J-code algorithm has op-codes designed to be space
|
||||||
|
saving. They are all one byte, but many are also considered as
|
||||||
|
white-space by the rules. This algorithm forms part of the same
|
||||||
|
string that the floating point constants are embedded
|
||||||
|
within. What does the ";" command do in J-code?
|
||||||
|
|
||||||
3. C pre-process the source ignoring #include lines
|
3. The J-code language is both stack based and variable based. This
|
||||||
4. C pre-process the source ignoring #define and #include lines
|
"uncleanliness" is not ideal from a computer science angle, but
|
||||||
|
when has cleanliness been considered as good in IOCCC? :-)
|
||||||
|
|
||||||
This does a good job of expanding out the code, but it does not
|
4. Association of unconnected data by implied function usage. Eg
|
||||||
clarify things greatly. The use of #defines has been restricted
|
use of strlen() and sizeof() simply to return useful numerical
|
||||||
primarily to a space-saving mechanism.
|
values, using irrelevant arguments.
|
||||||
|
|
||||||
Additionally, the use of typedefs means that the types used are
|
5. As we already have a dependency on ASCII this has been abused
|
||||||
still obscured unless further replacement edits are made.
|
further. Specifically some integer constants are specified as
|
||||||
|
ASCII and some ASCII constants are integers. This hides the true
|
||||||
|
meaning for the values.
|
||||||
|
|
||||||
5. Run it through a C beautifier.
|
6. Red herrings: there's a couple of pieces of code whose
|
||||||
|
appearance is just there to mislead the unfirm of mind.
|
||||||
|
I've only tried to include such examples in places where at
|
||||||
|
first glance the code appears to be executed.
|
||||||
|
|
||||||
GNU indent seems to do a reasonable job, provided that the
|
### References
|
||||||
#defines are expanded first. This doesn't lay the algorithm
|
|
||||||
particularly bare though as most of the obfuscations are not
|
|
||||||
simple code layouts.
|
|
||||||
|
|
||||||
6. Examine the algorithm.
|
[1] Astronomical algorithms (1st ed): page 59
|
||||||
|
Jean Meeus. Published by Willmann-Bell Inc.
|
||||||
|
|
||||||
The algorithm operates on two levels. The main visible level is
|
[2] Astronomical algorithms (1st ed): pages 285-299.
|
||||||
by taking a large string and breaking this down into a series of
|
Jean Meeus. Published by Willmann-Bell Inc.
|
||||||
op-codes (which I have termed J-code). These are then executed.
|
|
||||||
|
|
||||||
To get to the real method of how it works, you need to decode
|
[3] Skymap Pro, by Chris Marriott
|
||||||
the op-code string (which deliberately contains as many ; { and
|
http://www.skymap.com/
|
||||||
} symbols as possible), which will give you a reverse-polish
|
|
||||||
notation chunk of mathematics.
|
|
||||||
|
|
||||||
Sensible people amongst you will simply refer to the referenced
|
|
||||||
book :-)
|
|
||||||
|
|
||||||
7. Lint it.
|
|
||||||
|
|
||||||
I no longer have lint, although I do have access to Purify. I'm
|
|
||||||
happy to say that purify does not detect any memory errors or
|
|
||||||
memory leaks.
|
|
||||||
|
|
||||||
See below for compilation warnings.
|
|
||||||
|
|
||||||
8. Compile it.
|
|
||||||
|
|
||||||
I'm sorry to say that there are several warnings issued by the
|
|
||||||
compiler.
|
|
||||||
|
|
||||||
Firstly, the return type for X() is not specified, so it
|
|
||||||
defaults to int. Horror of all horrors - this function does not
|
|
||||||
return an integer type (it doesn't contain any specific
|
|
||||||
returns). The return value from X() is not accessed. The same
|
|
||||||
problem occurs in main - it does not return. However main never
|
|
||||||
exits unless there is a serious error.
|
|
||||||
|
|
||||||
The 6th argument of XDrawText (which should be XTextItem) is
|
|
||||||
passed as a compatible structure, but without casting. This is
|
|
||||||
to reduce code space. A more elegant solution is to remove the
|
|
||||||
"struct {...} Z" completely and use "XTextItem
|
|
||||||
f={i-127+r/3*2,r%3+r/3+1,0,E}" at the start of XDrawText
|
|
||||||
block. Although this is accepted by several compilers, it is not
|
|
||||||
strict ANSI due to the non-constant initialisers. A pity.
|
|
||||||
|
|
||||||
Note that I make use of usleep(). This is a POSIX call (it is
|
|
||||||
BSD), but it supported on many systems. It may be implemented
|
|
||||||
using select() or poll() if required, or as a final solution you
|
|
||||||
may change the usleep(10000) to sleep(1). To compile on systems
|
|
||||||
which do not have usleep, but do have select, the following may
|
|
||||||
suffice as an additional compiler argument:
|
|
||||||
|
|
||||||
-Dusleep={time_t v[2]={0,10000};select(0,0,0,0,v);}
|
|
||||||
|
|
||||||
Gcc complains about "unreachable code at beginning of switch
|
|
||||||
statement", although removing some of this code will prevent
|
|
||||||
the algorithm from working.
|
|
||||||
|
|
||||||
Gcc also suggests that I should be using extra parenthesis, but
|
|
||||||
I'm taking this as good comment :-)
|
|
||||||
|
|
||||||
|
|
||||||
In addition to the above, the program has the following useful(?)
|
|
||||||
obfuscations:
|
|
||||||
|
|
||||||
1. The algorithm requires many floating point numbers (about
|
|
||||||
50). These are encoded as ASCII.
|
|
||||||
|
|
||||||
2. The J-code algorithm has op-codes designed to be space
|
|
||||||
saving. They are all one byte, but many are also considered as
|
|
||||||
white-space by the rules. This algorithm forms part of the same
|
|
||||||
string that the floating point constants are embedded
|
|
||||||
within. What does the ";" command do in J-code?
|
|
||||||
|
|
||||||
3. The J-code language is both stack based and variable based. This
|
|
||||||
"uncleanliness" is not ideal from a computer science angle, but
|
|
||||||
when has cleanliness been considered as good in IOCCC? :-)
|
|
||||||
|
|
||||||
4. Association of unconnected data by implied function usage. Eg
|
|
||||||
use of strlen() and sizeof() simply to return useful numerical
|
|
||||||
values, using irrelevant arguments.
|
|
||||||
|
|
||||||
5. As we already have a dependency on ASCII this has been abused
|
|
||||||
further. Specifically some integer constants are specified as
|
|
||||||
ASCII and some ASCII constants are integers. This hides the true
|
|
||||||
meaning for the values.
|
|
||||||
|
|
||||||
6. Red herrings: there's a couple of pieces of code whose
|
|
||||||
appearance is just there to mislead the unfirm of mind.
|
|
||||||
I've only tried to include such examples in places where at
|
|
||||||
first glance the code appears to be executed.
|
|
||||||
|
|
||||||
|
|
||||||
References
|
|
||||||
----------
|
|
||||||
[1] Astronomical algorithms (1st ed): page 59
|
|
||||||
Jean Meeus. Published by Willmann-Bell Inc.
|
|
||||||
|
|
||||||
[2] Astronomical algorithms (1st ed): pages 285-299.
|
|
||||||
Jean Meeus. Published by Willmann-Bell Inc.
|
|
||||||
|
|
||||||
[3] Skymap Pro, by Chris Marriott
|
|
||||||
http://www.skymap.com/
|
|
||||||
Reference in new issue
Block a user