source: branches/1.3/gui/scripts/unirect2d.tcl @ 4007

# -*- mode: tcl; indent-tabs-mode: nil -*- 

# ----------------------------------------------------------------------
#  COMPONENT: unirect2d - represents a uniform rectangular 2-D mesh.
#
#  This object represents one field in an XML description of a device.
#  It simplifies the process of extracting data vectors that represent
#  the field.
# ======================================================================
#  AUTHOR:  Michael McLennan, Purdue University
#  Copyright (c) 2004-2012  HUBzero Foundation, LLC
#
#  See the file "license.terms" for information on usage and
#  redistribution of this file, and for a DISCLAIMER OF ALL WARRANTIES.
# ======================================================================
package require Itcl
package require BLT

namespace eval Rappture { # forward declaration }

itcl::class Rappture::Unirect2d {
    private variable _axisOrder "x y"
    private variable _xMax      0
    private variable _xMin      0
    private variable _xNum      0
    private variable _yMax      0
    private variable _yMin      0
    private variable _yNum      0
    private variable _hints
    private variable _vtkdata ""
    private variable _numPoints 0

    private common _xp2obj       ;      # used for fetch/release ref counting
    private common _obj2ref      ;      # used for fetch/release ref counting
    private variable _isValid 0;        # Indicates if the data is valid.

    constructor {xmlobj path} { 
        # defined below 
    }
    destructor { 
        # defined below 
    }
    public proc fetch {xmlobj path}
    public proc release {obj}
    public method limits {axis}
    public method blob {}
    public method hints {{keyword ""}} 
    public method mesh {}
    public method dimensions {} {
        return 2
    }
    public method isvalid {} {
        return $_isValid
    }
    public method numpoints {} {
        return $_numPoints
    }
    public method vtkdata {} {
        return $_vtkdata
    }

    private method GetString { obj path varName }
    private method GetValue { obj path varName }
    private method GetSize { obj path varName }
    
}

#
# fetch <xmlobj> <path>
#
#    Clients use this instead of a constructor to fetch the Mesh for a
#    particular <path> in the <xmlobj>.  When the client is done with the mesh,
#    he calls "release" to decrement the reference count.  When the mesh is no
#    longer needed, it is cleaned up automatically.
#
itcl::body Rappture::Unirect2d::fetch {xmlobj path} {
    set handle "$xmlobj|$path"
    if {[info exists _xp2obj($handle)]} {
        set obj $_xp2obj($handle)
        incr _obj2ref($obj)
        return $obj
    }
    set obj [Rappture::Unirect2d ::#auto $xmlobj $path]
    set _xp2obj($handle) $obj
    set _obj2ref($obj) 1
    return $obj
}

# ----------------------------------------------------------------------
# USAGE: Rappture::Mesh::release <obj>
#
# Clients call this when they're no longer using a Mesh fetched
# previously by the "fetch" proc.  This decrements the reference
# count for the mesh and destroys the object when it is no longer
# in use.
# ----------------------------------------------------------------------
itcl::body Rappture::Unirect2d::release { obj } {
    if { ![info exists _obj2ref($obj)] } {
        error "can't find reference count for $obj"
    }
    incr _obj2ref($obj) -1
    if {$_obj2ref($obj) <= 0} {
        unset _obj2ref($obj)
        foreach handle [array names _xp2obj] {
            if {$_xp2obj($handle) == $obj} {
                unset _xp2obj($handle)
            }
        }
        itcl::delete object $obj
    }
}

# ----------------------------------------------------------------------
# Constructor
# ----------------------------------------------------------------------
itcl::body Rappture::Unirect2d::constructor {xmlobj path} {
    if {![Rappture::library isvalid $xmlobj]} {
        error "bad value \"$xmlobj\": should be Rappture::library"
    }
    set m [$xmlobj element -as object $path]
    GetValue $m "xaxis.min" _xMin
    GetValue $m "xaxis.max" _xMax
    GetSize $m "xaxis.numpoints" _xNum
    GetValue $m "yaxis.min" _yMin
    GetValue $m "yaxis.max" _yMax
    GetSize $m "yaxis.numpoints" _yNum
    foreach {key path} {
        group   about.group
        label   about.label
        color   about.color
        style   about.style
        type    about.type
        xlabel  xaxis.label
        xdesc   xaxis.description
        xunits  xaxis.units
        xscale  xaxis.scale
        xmin    xaxis.min
        xmax    xaxis.max
        ylabel  yaxis.label
        ydesc   yaxis.description
        yunits  yaxis.units
        yscale  yaxis.scale
        ymin    yaxis.min
        ymax    yaxis.max
        type    about.type
    } {
        set str [$m get $path]
        if {"" != $str} {
            set _hints($key) $str
        }
    }
    itcl::delete object $m
    set _numPoints [expr $_xNum * $_yNum]
    if { $_numPoints == 0 } {
        set _vtkdata ""
        return
    }
    append out "DATASET STRUCTURED_POINTS\n"
    append out "DIMENSIONS $_xNum $_yNum 1"
    set xSpace [expr ($_xMax - $_xMin) / double($_xNum - 1)]
    set ySpace [expr ($_yMax - $_yMin) / double($_yNum - 1)]
    append out "SPACING $xSpace $ySpace 0\n"
    append out "ORIGIN 0 0 0\n"
    set _vtkdata $out
    set _isValid 1
}

# ----------------------------------------------------------------------
# Destructor
# ----------------------------------------------------------------------
itcl::body Rappture::Unirect2d::destructor {} {
    # empty
}

# ----------------------------------------------------------------------
# method blob 
#       Returns a base64 encoded, gzipped Tcl list that represents the
#       Tcl command and data to recreate the uniform rectangular grid 
#       on the nanovis server.
# ----------------------------------------------------------------------
itcl::body Rappture::Unirect2d::blob {} {
    set data "unirect2d"
    lappend data "xmin" $_xMin "xmax" $_xMax "xnum" $_xNum
    lappend data "ymin" $_yMin "ymax" $_yMax "ynum" $_yNum
    lappend data "xmin" $_xMin "ymin" $_yMin "xmax" $_xMax "ymax" $_yMax
    return $data
}

# ----------------------------------------------------------------------
# method mesh
#       Returns a base64 encoded, gzipped Tcl list that represents the
#       Tcl command and data to recreate the uniform rectangular grid 
#       on the nanovis server.
# ----------------------------------------------------------------------
itcl::body Rappture::Unirect2d::mesh {} {
    lappend out $_xMin $_xMax $_xNum $_yMin $_yMax $_yNum
    return $out
}

# ----------------------------------------------------------------------
# method limits <axis>
#       Returns a list {min max} representing the limits for the 
#       specified axis.
# ----------------------------------------------------------------------
itcl::body Rappture::Unirect2d::limits {which} {
    set min ""
    set max ""
    switch -- $which {
        x - xlin - xlog {
            set min $_xMin
            set max $_xMax
            set axis "xaxis"
        }
        y - ylin - ylog {
            set min $_yMin
            set max $_yMax
            set axis "yaxis"
        }
        default {
            error "unknown axis description \"$which\""
        }
    }
    return [list $min $max]
}


# ----------------------------------------------------------------------
# USAGE: hints ?<keyword>?
#
# Returns a list of key/value pairs for various hints about plotting
# this curve.  If a particular <keyword> is specified, then it returns
# the hint for that <keyword>, if it exists.
# ----------------------------------------------------------------------
itcl::body Rappture::Unirect2d::hints { {keyword ""} } {
    if {[info exists _hints(xlabel)] && "" != $_hints(xlabel)
        && [info exists _hints(xunits)] && "" != $_hints(xunits)} {
        set _hints(xlabel) "$_hints(xlabel) ($_hints(xunits))"
    }
    if {[info exists _hints(ylabel)] && "" != $_hints(ylabel)
        && [info exists _hints(yunits)] && "" != $_hints(yunits)} {
        set _hints(ylabel) "$_hints(ylabel) ($_hints(yunits))"
    }
    
    if {[info exists _hints(group)] && [info exists _hints(label)]} {
        # pop-up help for each curve
        set _hints(tooltip) $_hints(label)
    }
    if {$keyword != ""} {
        if {[info exists _hints($keyword)]} {
            return $_hints($keyword)
        }
        return ""
    }
    return [array get _hints]
}


itcl::body Rappture::Unirect2d::GetSize { obj path varName } {
    set string [$obj get $path]
    if { [scan $string "%d" value] != 1 || $value < 0 } {
        puts stderr "can't get size \"$string\" of \"$path\""
        return
    }
    upvar $varName size
    set size $value
}

itcl::body Rappture::Unirect2d::GetValue { obj path varName } {
    set string [$obj get $path]
    if { [scan $string "%g" value] != 1 } {
        return
    }
    upvar $varName number
    set number $value
}

itcl::body Rappture::Unirect2d::GetString { obj path varName } {
    set string [$obj get $path]
    if { $string == "" } {
        puts stderr "can't get string \"$string\" of \"$path\""
        return
    }
    upvar $varName str
    set str $string
}