int _find_next_intercept();

    int raw_advance_0();
    void flip();

int ray_def::_find_next_intercept()

int ray_def::raw_advance_0()

/*
 * Mirror ray into quadrant 0 or back.
 * this.quadrant itself is not touched (used for the flip back).
 */
void ray_def::flip()
{
    int signx[] = {1, -1, -1,  1};
    int signy[] = {1,  1, -1, -1};
    accx *= signx[quadrant];
    accy *= signy[quadrant];
}

    switch (quadrant)
    {
    case 0:
        // going down-right
        rc = _find_next_intercept();
        break;
    case 1:
        // going down-left
        accx *= -1;
        rc   = _find_next_intercept();
        accx *= -1;
        break;
    case 2:
        // going up-left
        accx *= -1;
        accy *= -1;
        rc   = _find_next_intercept();
        accx *= -1;
        accy *= -1;
        break;
    case 3:
        // going up-right
        accy *= -1;
        rc   = _find_next_intercept();
        accy *= -1;
        break;
    default:
        rc = -1;
    }

    flip();
    rc = raw_advance_0();
    flip();

// Store the visited cells in xpos[] and ypos[], and

// Store the visited cells in pos[], and

        copy._find_next_intercept();

        copy.raw_advance();

# -*- Makefile -*- for Dungeon Crawl (unix)
GAME = crawl
# this file contains a list of the libraries.
# it will make a variable called OBJECTS that contains all the libraries
include makefile.obj
OBJECTS += libunix.o crash-u.o
CXX = g++
DELETE = rm -f
COPY = cp
OS_TYPE = UNIX
# To get stack trace symbols.
LDFLAGS = -rdynamic
# Change this to y (case-sensitive!) if you want to use Unicode glyphs
# in the map, and you have libncursesw available.
UNICODE_GLYPHS = n
# If you're using UNICODE_GLYPHS=y, and have a preferred Unicode
# (UTF-8) locale you want Crawl to use, you can set it here. The
# default is en_US.UTF-8. If you'd prefer that Crawl use the locale
# as set in your environment LC_* variables, use UNICODE_LOCALE = .
UNICODE_LOCALE =
# If you have lex and yacc, set DOYACC to y (lowercase y).
DOYACC := y
# Permissions to set on the game executable.
MCHMOD := 2755
# Permissions to set on the save directory.
MCHMOD_SAVEDIR := 775
# The user:group to install the game as.
INSTALL_UGRP := games:games
INSTALLDIR   := /usr/games/crawl
# If you're installing Crawl for multiple users, you *must* set this to a
# valid path before building Crawl. This is not necessary if you are building
# Crawl for a single user.
# SAVEDIR := /usr/games/crawl/saves/
# DATADIR := /usr/games/crawl/data/
LEX  := flex
YACC := bison -y
LUASRC := util/lua/src
LUALIB = lua
LUALIBA = l$(LUALIB).a
SQLSRC   := util/sqlite
SQLLIB   := sqlite3
SQLLIBA  := lib$(SQLLIB).a
FSQLLIBA := $(SQLSRC)/$(SQLLIBA)
LIBDBM         := $(FSQLLIBA)
EXTRA_INCLUDES += -I$(SQLSRC)
EXTRA_DEPENDS  += $(FSQLLIBA)
LIB = -l$(LIBCURS) -L$(LUASRC) -l$(LUALIB) $(LIBDBM)
INCLUDES := $(INCLUDES) -Iutil -I. -I$(LUASRC) $(EXTRA_INCLUDES)
CFWARN := -Wall -Wno-parentheses -Wwrite-strings -Wshadow -pedantic
CFOTHERS := -fsigned-char -D$(OS_TYPE) $(EXTRA_FLAGS) -DCLUA_BINDINGS
ifneq ($(HURRY),y)
ifneq ($(DEBUG_CRAWL),y)
CFWARN += -Wuninitialized
CFOTHERS += -O2
endif
endif
ifneq ($(strip $(SAVEDIR)),)
CFOTHERS += '-DSAVE_DIR_PATH="$(strip $(SAVEDIR))"'
endif
ifneq ($(strip $(DATADIR)),)
CFOTHERS += '-DDATA_DIR_PATH="$(strip $(DATADIR))"'
endif
ifeq ($(strip $(UNICODE_GLYPHS)),y)
# Include path for (n)curses with Unicode support.
INCLUDES += -I/usr/include/ncursesw
# Your ncurses library may include Unicode support, and you may not have a
# separate libncursesw; in that case, change this line accordingly.
LIBCURS  = ncursesw
CFOTHERS += -DUNICODE_GLYPHS
ifneq ($(strip $(UNICODE_LOCALE)),)
ifneq ($(strip $(UNICODE_LOCALE)),.)
CFOTHERS += -DUNICODE_LOCALE=\"$(strip $(UNICODE_LOCALE))\"
else
CFOTHERS += -DUNICODE_LOCALE=\"\"
endif
endif
# The standard ncurses library also supports Unicode on Mac OS/Darwin.
ifeq ($(shell uname),Darwin)
LIBCURS = ncurses
endif
else
# Include path for curses or ncurses (non-Unicode).
INCLUDES += -I/usr/include/ncurses
LIBCURS  = ncurses
endif
CFLAGS  := $(INCLUDES) $(CFWARN) $(CFOTHERS)
YCFLAGS := $(INCLUDES) $(CFOTHERS)
UTIL = util/
YTABC  := levcomp.tab.c
YTABH  := levcomp.tab.h
OBJECTS := $(UTIL)levcomp.tab.o $(UTIL)levcomp.lex.o $(OBJECTS)
ifeq ($(strip $(LEX)),)
DOYACC :=
endif
ifeq ($(strip $(YACC)),)
DOYACC :=
endif
GAME_DEPENDS := $(LUASRC)$(LUALIBA) $(EXTRA_DEPENDS) $(OBJECTS)
SRC_PKG_BASE := stone_soup
SRC_VERSION  := $(shell egrep 'VER_NUM  *".*"' version.h | \
			egrep -o '[0-9]\.[0-9](\.[0-9])?')
PKG_SRC_DIR  := $(SRC_PKG_BASE)-$(SRC_VERSION)-src
SRC_PKG_TAR  := $(PKG_SRC_DIR).tbz2
SRC_PKG_ZIP  := $(PKG_SRC_DIR).zip
PKG_TIDY_LIST := $(UTIL)*.o $(LEVCOMP) *.o \
		$(UTIL)*.tab.cc $(UTIL)*.tab.h $(UTIL)*.lex.cc *.ixx
PKG_EXCLUDES  := $(PWD)/misc/src-pkg-excludes.lst
##########################################################################
all: $(GAME)
test: $(GAME)
	$(PWD)/$(GAME) -test
##########################################################################
# Dependencies
DEPENDENCY_MKF := makefile.dep
depend: $(OBJECTS:.o=.cc)
	rm -f $(DEPENDENCY_MKF).tmp
	@for i in $^; do \
	    echo "Updating dependencies for $$i"; \
	    $(CXX) -MM $(CFLAGS) $$i >>$(DEPENDENCY_MKF).tmp 2>/dev/null; \
	done
	mv -f $(DEPENDENCY_MKF).tmp $(DEPENDENCY_MKF)
-include $(DEPENDENCY_MKF)
##########################################################################
# The level compiler
#
ifeq ($(DOYACC),y)
prebuildyacc:	$(UTIL)levcomp.tab.cc $(UTIL)levcomp.tab.h $(UTIL)levcomp.lex.cc
		$(COPY) $^ prebuilt/
$(UTIL)levcomp.tab.cc: $(UTIL)levcomp.ypp
		cd $(UTIL) && $(YACC) -d -b levcomp levcomp.ypp \
			   && mv $(YTABC) levcomp.tab.cc || false
$(UTIL)levcomp.lex.cc: $(UTIL)levcomp.lpp
		cd $(UTIL) && $(LEX) -olevcomp.lex.cc levcomp.lpp
else
# Pull the level-compiler stuff up from prebuilt/
$(UTIL)levcomp.tab.cc: prebuilt/levcomp.tab.cc
		$(COPY) prebuilt/*.h $(UTIL)
		$(COPY) $< $@
$(UTIL)levcomp.lex.cc: prebuilt/levcomp.lex.cc
		$(COPY) $< $@
endif
##########################################################################
##########################################################################
# The actual build targets
#
install: $(GAME)
ifeq ($(DATADIR),)
	$(error DATADIR not set! Set DATADIR and run make clean install again)
endif
	[ -d $(INSTALLDIR) ] || mkdir -p $(INSTALLDIR)
	$(COPY) $(GAME) $(INSTALLDIR)
	chown $(INSTALL_UGRP) $(INSTALLDIR)/$(GAME)
	chmod ${MCHMOD} ${INSTALLDIR}/$(GAME)
	mkdir -p $(DATADIR)/dat
	mkdir -p $(DATADIR)/dat/lua
	mkdir -p $(DATADIR)/dat/clua
	mkdir -p $(DATADIR)/dat/descript
	mkdir -p $(DATADIR)/dat/database
	$(COPY) dat/*.des $(DATADIR)/dat
	$(COPY) dat/lua/*.lua $(DATADIR)/dat/lua
	$(COPY) dat/clua/*.lua $(DATADIR)/dat/clua
	$(COPY) dat/descript/*.txt $(DATADIR)/dat/descript
	$(COPY) dat/database/*.txt $(DATADIR)/dat/database
	mkdir -p $(DATADIR)/settings
	$(COPY) ../settings/* $(DATADIR)/settings/
	mkdir -p $(DATADIR)/docs
	$(COPY) ../docs/*.txt $(DATADIR)/docs
	chown -R $(INSTALL_UGRP) $(DATADIR)
ifneq ($(SAVEDIR),)
	mkdir -p $(SAVEDIR)
	chown $(INSTALL_UGRP) $(SAVEDIR)
	chmod $(MCHMOD_SAVEDIR) $(SAVEDIR)
endif
clean:
	$(DELETE) *.o
	$(DELETE) $(UTIL)*.o
	$(DELETE) $(LEVCOMP)
	$(DELETE) $(UTIL)*.tab.cc $(UTIL)*.tab.c $(UTIL)*.tab.h $(UTIL)*.lex.cc
	$(DELETE) *.ixx
clean-lua:
	+$(MAKE) -C $(LUASRC) clean
clean-sql:
	+$(MAKE) -C $(SQLSRC) clean
distclean: clean clean-lua clean-sql
	$(DELETE) bones.*
	$(DELETE) morgue.txt
	$(DELETE) scores
	$(DELETE) $(GAME)
	$(DELETE) *.sav
	$(DELETE) core
	$(DELETE) *.0*
	$(DELETE) *.lab
	$(DELETE) $(DEPENDENCY_MKF)
$(GAME): $(GAME_DEPENDS)
	${CXX} ${LDFLAGS} $(CFLAGS) $(OBJECTS) -o $(GAME) $(LIB)
.PHONY : debug
debug: $(GAME)
profile: $(GAME_DEPENDS)
	${CXX} -g -p ${LDFLAGS} $(CFLAGS) $(OBJECTS) -o $(GAME) $(LIB)
.cc.o:
	${CXX} ${CFLAGS} -c $<
# [ds] Note we don't use the standard CFLAGS here; that's intentional, most
# flex/bison combos I've tried don't produce code that passes the warnings
# test.
$(UTIL)%.o: $(UTIL)%.cc
	$(CXX) $(YCFLAGS) -o $@ -c $<
#############################################################################
# Build Lua
$(LUASRC)$(LUALIBA):
	echo Building Lua...
	+$(MAKE) -C $(LUASRC) crawl_unix
#############################################################################
# Build SQLite
$(FSQLLIBA):
	echo Building SQLite
	+$(MAKE) -C $(SQLSRC)
#############################################################################
# Build unrandart data
art-data.h: art-data.txt util/art-data.pl art-func.h
	util/art-data.pl
#############################################################################
# Packaging a source tarball for release
#
# To package, you *must* have lex and yacc to generate the intermediates.
ifeq ($(DOYACC),y)
package-source: distclean prebuildyacc pkgtidy depend removeold vlink \
				pkgtarbz2 pkgzip
pkgtidy:
	$(DELETE) $(PKG_TIDY_LIST)
removeold:
	if [ -f ../../$(SRC_PKG_TAR) ]; then $(DELETE) ../../$(SRC_PKG_TAR); fi
	if [ -f ../../$(SRC_PKG_ZIP) ]; then $(DELETE) ../../$(SRC_PKG_ZIP); fi
# [ds] Existing directory names could produce a bad package!
vlink:
	cd .. && WHERE=$$PWD && cd .. && \
		( [ -e $(PKG_SRC_DIR) ] || ln -sf $$WHERE $(PKG_SRC_DIR) )
pkgtarbz2:
	cd ../.. && tar -ch --bzip2 -f $(SRC_PKG_TAR) \
		-X $(PKG_EXCLUDES) $(PKG_SRC_DIR)
pkgzip:
	cd ../.. && zip -rq $(SRC_PKG_ZIP) $(PKG_SRC_DIR) \
		-x@$(PKG_EXCLUDES)
endif