#!/bin/ksh93

#
# CDDL HEADER START
#
# The contents of this file are subject to the terms of the
# Common Development and Distribution License (the "License").
# You may not use this file except in compliance with the License.
#
# You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
# or http://www.opensolaris.org/os/licensing.
# See the License for the specific language governing permissions
# and limitations under the License.
#
# When distributing Covered Code, include this CDDL HEADER in each
# file and include the License file at usr/src/OPENSOLARIS.LICENSE.
# If applicable, add the following below this CDDL HEADER, with the
# fields enclosed by brackets "[]" replaced with your own identifying
# information: Portions Copyright [yyyy] [name of copyright owner]
#
# CDDL HEADER END
#

#
# Copyright 2006 Sun Microsystems, Inc.  All rights reserved.
# Use is subject to license terms.
#
# ident	"@(#)mandelbrot1.ksh	1.1	06/03/24 SMI"
#

export PATH=/bin:/usr/bin:/usr/X11R6/bin:/usr/openwin/bin

function printmsg
{
    print "$@" >&2
}

function fatal_error
{
    print "${progname}: $@" >&2
}

function print_color
{   
    print -n "${symbollist:${1}:1}"
}

function mandelbrot
{
    float   x=$1
    float   y=$2
    float   xx
    float   yy
    float   x1=$3
    float   y1=$4
    integer iteration=$5
    integer max_iteration=$6
    float   mag
       
    for (( mag=0 ; mag < max_mag && iteration < max_iteration ; iteration++ )) ; do
        (( xx=x*x ))
        (( yy=y*y ))
        (( mag=xx+yy ))

        (( y=x*y*2+y1 ))
        (( x=xx-yy+x1 ))
    done

    print $iteration

    return 0
}

function loop_serial
{
    for (( y=y_min ; y < y_max ; y+=stepwidth )) ; do
	for (( x=x_min ; x < x_max ; x+=stepwidth )) ; do
            print_color $(mandelbrot ${x} ${y} ${x} ${y} 1 ${symbollistlen})
	done

	print
    done
}

function loop_parallel
{
    integer numjobs=0
    
    # "renice" worker jobs
    set -o bgnice
    
    # try to generate a job identifer prefix which is unique across multiple hosts
    jobident="job_host_$(uname -n)pid_$$_ppid${PPID}"
    
    printmsg "## prepare..."
    for (( y=y_min ; y < y_max ; y+=stepwidth )) ; do
        rm -f "/tmp/mandelbrot_${jobident}_child_$y.joboutput"

	let numjobs++
    done

    printmsg "## running ${numjobs} children..."
    for (( y=y_min ; y < y_max ; y+=stepwidth )) ; do
        (    
	    for (( x=x_min ; x < x_max ; x+=stepwidth )) ; do
	        print_color $(mandelbrot ${x} ${y} ${x} ${y} 1 ${symbollistlen})
	    done >"/tmp/mandelbrot_${jobident}_child_$y.joboutput"
	) &	
    done
    
    printmsg "## waiting for ${numjobs} children..."
    wait

    printmsg "## output:"
    for (( y=y_min ; y < y_max ; y+=stepwidth )) ; do
        print "$(cat "/tmp/mandelbrot_${jobident}_child_$y.joboutput")"
        rm "/tmp/mandelbrot_${jobident}_child_$y.joboutput"
    done
}

# main
builtin printf
builtin cat
builtin rm
builtin sleep
builtin uname # loop_parallel needs the ksh93 builtin version to generate unique job file names

float x_max
float x_min
float y_max
float y_min
float m_width
float m_height
float max_mag
float stepwidth

# make sure ${COLUMN} and ${LINES} are set
eval $(resize)

symbollist="    .0123456789abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ#"
symbollistlen=$(( ${#symbollist} - 1))
mode="parallel"
progname="${0}"
max_mag=400
stepwidth=0.1

let m_width=COLUMNS-1 m_height=LINES-2

while [ $# -gt 1 ] ; do
    case "${1}" in
        -w | -width)   shift ; m_width=$1 ;;
        -h | -height)  shift ; m_height=$1 ;;
        -symbols)      shift ; symbollist=$1 ;;
        -mag)          shift ; max_mag=$1 ;;
        -stepwidth)    shift ; stepwidth=$1 ;;
	-serial)       mode="serial" ;;
	-parallel)     mode="parallel" ;;
        -mode)         shift ; mode=$1 ;;
	*)             fatal_error "Unknown option '${1}'."
    esac
    shift
done

printmsg "# width=${m_width}"
printmsg "# height=${m_height}"
printmsg "# max_mag=${max_mag}"
printmsg "# stepwidth=${stepwidth}"
printmsg "# symbollist='${symbollist}'"
printmsg "# mode=${mode}"

symbollistlen=$(( ${#symbollist} - 1))

let x_max=m_width*stepwidth/2.  x_min=-x_max
let y_max=m_height*stepwidth/2. y_min=-y_max

case "${mode}" in
    parallel) loop_parallel ;;
    serial)   loop_serial ;;
    *) fatal_error "Unknown mode '${mode}'."
esac

# EOF.