1 | # ---------------------------------------------------------------------- |
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2 | # COMPONENT: field - extracts data from an XML description of a field |
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3 | # |
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4 | # This object represents one field in an XML description of a device. |
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5 | # It simplifies the process of extracting data vectors that represent |
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6 | # the field. |
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7 | # ====================================================================== |
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8 | # AUTHOR: Michael McLennan, Purdue University |
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9 | # Copyright (c) 2004-2005 Purdue Research Foundation |
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10 | # |
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11 | # See the file "license.terms" for information on usage and |
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12 | # redistribution of this file, and for a DISCLAIMER OF ALL WARRANTIES. |
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13 | # ====================================================================== |
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14 | package require Itcl |
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15 | package require BLT |
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16 | |
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17 | namespace eval Rappture { # forward declaration } |
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18 | |
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19 | itcl::class Rappture::Field { |
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20 | constructor {xmlobj path} { # defined below } |
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21 | destructor { # defined below } |
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22 | |
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23 | public method components {args} |
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24 | public method mesh {{what -overall}} |
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25 | public method values {{what -overall}} |
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26 | public method limits {axis} |
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27 | public method controls {option args} |
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28 | public method hints {{key ""}} |
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29 | |
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30 | protected method _build {} |
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31 | protected method _getValue {expr} |
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32 | |
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33 | private variable _xmlobj "" ;# ref to XML obj with device data |
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34 | |
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35 | private variable _units "" ;# system of units for this field |
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36 | private variable _limits ;# maps box name => {z0 z1} limits |
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37 | private variable _zmax 0 ;# length of the device |
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38 | |
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39 | private variable _field "" ;# lib obj representing this field |
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40 | private variable _comp2dims ;# maps component name => dimensionality |
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41 | private variable _comp2xy ;# maps component name => x,y vectors |
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42 | private variable _comp2vtk ;# maps component name => vtkFloatArray |
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43 | private variable _comp2style ;# maps component name => style settings |
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44 | private variable _comp2cntls ;# maps component name => x,y control points |
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45 | |
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46 | private common _counter 0 ;# counter for unique vector names |
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47 | } |
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48 | |
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49 | # ---------------------------------------------------------------------- |
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50 | # CONSTRUCTOR |
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51 | # ---------------------------------------------------------------------- |
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52 | itcl::body Rappture::Field::constructor {xmlobj path} { |
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53 | if {![Rappture::library isvalid $xmlobj]} { |
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54 | error "bad value \"$xmlobj\": should be Rappture::library" |
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55 | } |
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56 | set _xmlobj $xmlobj |
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57 | set _field [$xmlobj element -as object $path] |
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58 | set _units [$_field get units] |
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59 | |
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60 | set xunits [$xmlobj get units] |
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61 | if {"" == $xunits || "arbitrary" == $xunits} { |
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62 | set xunits "um" |
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63 | } |
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64 | |
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65 | # determine the overall size of the device |
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66 | set z0 [set z1 0] |
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67 | foreach elem [$_xmlobj children components] { |
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68 | switch -glob -- $elem { |
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69 | box* { |
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70 | if {![regexp {[0-9]$} $elem]} { |
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71 | set elem "${elem}0" |
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72 | } |
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73 | set z0 [$_xmlobj get components.$elem.corner0] |
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74 | set z0 [Rappture::Units::convert $z0 \ |
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75 | -context $xunits -to $xunits -units off] |
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76 | |
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77 | set z1 [$_xmlobj get components.$elem.corner1] |
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78 | set z1 [Rappture::Units::convert $z1 \ |
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79 | -context $xunits -to $xunits -units off] |
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80 | |
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81 | set _limits($elem) [list $z0 $z1] |
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82 | } |
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83 | } |
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84 | } |
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85 | set _zmax $z1 |
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86 | |
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87 | # build up vectors for various components of the field |
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88 | _build |
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89 | } |
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90 | |
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91 | # ---------------------------------------------------------------------- |
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92 | # DESTRUCTOR |
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93 | # ---------------------------------------------------------------------- |
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94 | itcl::body Rappture::Field::destructor {} { |
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95 | itcl::delete object $_field |
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96 | # don't destroy the _xmlobj! we don't own it! |
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97 | |
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98 | foreach name [array names _comp2xy] { |
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99 | eval blt::vector destroy $_comp2xy($name) |
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100 | } |
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101 | foreach name [array names _comp2vtk] { |
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102 | set mobj [lindex $_comp2vtk($name) 0] |
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103 | set class [$mobj info class] |
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104 | ${class}::release $mobj |
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105 | |
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106 | set fobj [lindex $_comp2vtk($name) 1] |
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107 | rename $fobj "" |
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108 | } |
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109 | } |
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110 | |
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111 | # ---------------------------------------------------------------------- |
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112 | # USAGE: components ?-name|-dimensions|-style? ?<pattern>? |
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113 | # |
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114 | # Returns a list of names or types for the various components of |
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115 | # this field. If the optional glob-style <pattern> is specified, |
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116 | # then it returns only the components with names matching the pattern. |
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117 | # ---------------------------------------------------------------------- |
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118 | itcl::body Rappture::Field::components {args} { |
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119 | Rappture::getopts args params { |
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120 | flag what -name default |
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121 | flag what -dimensions |
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122 | flag what -style |
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123 | } |
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124 | |
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125 | set pattern * |
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126 | if {[llength $args] > 0} { |
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127 | set pattern [lindex $args 0] |
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128 | set args [lrange $args 1 end] |
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129 | } |
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130 | if {[llength $args] > 0} { |
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131 | error "wrong # args: should be \"components ?switches? ?pattern?\"" |
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132 | } |
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133 | |
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134 | set rlist "" |
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135 | foreach name [array names _comp2dims $pattern] { |
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136 | switch -- $params(what) { |
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137 | -name { lappend rlist $name } |
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138 | -dimensions { lappend rlist $_comp2dims($name) } |
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139 | -style { lappend rlist $_comp2style($name) } |
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140 | } |
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141 | } |
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142 | return $rlist |
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143 | } |
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144 | |
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145 | # ---------------------------------------------------------------------- |
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146 | # USAGE: mesh ?<name>? |
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147 | # |
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148 | # Returns a list {xvec yvec} for the specified field component <name>. |
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149 | # If the name is not specified, then it returns the vectors for the |
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150 | # overall field (sum of all components). |
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151 | # ---------------------------------------------------------------------- |
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152 | itcl::body Rappture::Field::mesh {{what -overall}} { |
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153 | if {$what == "component0"} { |
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154 | set what "component" |
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155 | } |
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156 | if {[info exists _comp2xy($what)]} { |
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157 | return [lindex $_comp2xy($what) 0] ;# return xv |
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158 | } |
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159 | if {[info exists _comp2vtk($what)]} { |
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160 | set mobj [lindex $_comp2vtk($what) 0] |
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161 | return [$mobj mesh] |
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162 | } |
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163 | error "bad option \"$what\": should be [join [lsort [array names _comp2dims]] {, }]" |
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164 | } |
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165 | |
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166 | # ---------------------------------------------------------------------- |
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167 | # USAGE: values ?<name>? |
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168 | # |
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169 | # Returns a list {xvec yvec} for the specified field component <name>. |
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170 | # If the name is not specified, then it returns the vectors for the |
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171 | # overall field (sum of all components). |
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172 | # ---------------------------------------------------------------------- |
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173 | itcl::body Rappture::Field::values {{what -overall}} { |
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174 | if {$what == "component0"} { |
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175 | set what "component" |
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176 | } |
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177 | if {[info exists _comp2xy($what)]} { |
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178 | return [lindex $_comp2xy($what) 1] ;# return yv |
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179 | } |
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180 | if {[info exists _comp2vtk($what)]} { |
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181 | return [lindex $_comp2vtk($what) 1] ;# return vtkFloatArray |
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182 | } |
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183 | error "bad option \"$what\": should be [join [lsort [array names _comp2dims]] {, }]" |
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184 | } |
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185 | |
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186 | # ---------------------------------------------------------------------- |
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187 | # USAGE: limits <axis> |
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188 | # |
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189 | # Returns a list {min max} representing the limits for the specified |
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190 | # axis. |
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191 | # ---------------------------------------------------------------------- |
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192 | itcl::body Rappture::Field::limits {which} { |
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193 | set min "" |
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194 | set max "" |
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195 | |
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196 | blt::vector create tmp zero |
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197 | foreach comp [array names _comp2dims] { |
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198 | switch -- $_comp2dims($comp) { |
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199 | 1D { |
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200 | switch -- $which { |
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201 | x - xlin { set pos 0; set log 0; set axis xaxis } |
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202 | xlog { set pos 0; set log 1; set axis xaxis } |
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203 | y - ylin - v - vlin { set pos 1; set log 0; set axis yaxis } |
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204 | ylog - vlog { set pos 1; set log 1; set axis yaxis } |
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205 | default { |
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206 | error "bad option \"$which\": should be x, xlin, xlog, y, ylin, ylog, v, vlin, vlog" |
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207 | } |
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208 | } |
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209 | |
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210 | set vname [lindex $_comp2xy($comp) $pos] |
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211 | $vname variable vec |
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212 | |
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213 | if {$log} { |
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214 | # on a log scale, use abs value and ignore 0's |
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215 | $vname dup tmp |
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216 | $vname dup zero |
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217 | zero expr {tmp == 0} ;# find the 0's |
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218 | tmp expr {abs(tmp)} ;# get the abs value |
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219 | tmp expr {tmp + zero*max(tmp)} ;# replace 0's with abs max |
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220 | set vmin [blt::vector expr min(tmp)] |
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221 | set vmax [blt::vector expr max(tmp)] |
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222 | } else { |
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223 | set vmin $vec(min) |
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224 | set vmax $vec(max) |
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225 | } |
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226 | |
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227 | if {"" == $min} { |
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228 | set min $vmin |
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229 | } elseif {$vmin < $min} { |
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230 | set min $vmin |
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231 | } |
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232 | if {"" == $max} { |
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233 | set max $vmax |
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234 | } elseif {$vmax > $max} { |
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235 | set max $vmax |
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236 | } |
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237 | } |
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238 | 2D - 3D { |
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239 | foreach {xv yv} $_comp2vtk($comp) break |
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240 | switch -- $which { |
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241 | x - xlin - xlog { |
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242 | foreach {vmin vmax} [$xv limits x] break |
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243 | set axis xaxis |
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244 | } |
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245 | y - ylin - ylog { |
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246 | foreach {vmin vmax} [$xv limits y] break |
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247 | set axis yaxis |
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248 | } |
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249 | z - zlin - zlog { |
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250 | foreach {vmin vmax} [$xv limits z] break |
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251 | set axis zaxis |
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252 | } |
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253 | v - vlin - vlog { |
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254 | catch {unset style} |
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255 | array set style $_comp2style($comp) |
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256 | if {[info exists style(-min)] && [info exists style(-max)]} { |
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257 | # This component has its own hard-coded |
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258 | # min/max range. Ignore it for overall limits. |
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259 | set vmin $min |
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260 | set vmax $max |
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261 | } else { |
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262 | foreach {vmin vmax} [$yv GetRange] break |
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263 | } |
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264 | set axis vaxis |
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265 | } |
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266 | default { |
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267 | error "bad option \"$which\": should be x, xlin, xlog, y, ylin, ylog, v, vlin, vlog" |
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268 | } |
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269 | } |
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270 | } |
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271 | } |
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272 | if {"" == $min} { |
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273 | set min $vmin |
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274 | } elseif {$vmin < $min} { |
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275 | set min $vmin |
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276 | } |
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277 | if {"" == $max} { |
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278 | set max $vmax |
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279 | } elseif {$vmax > $max} { |
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280 | set max $vmax |
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281 | } |
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282 | } |
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283 | blt::vector destroy tmp zero |
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284 | |
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285 | set val [$_field get $axis.min] |
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286 | if {"" != $val && "" != $min} { |
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287 | if {$val > $min} { |
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288 | # tool specified this min -- don't go any lower |
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289 | set min $val |
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290 | } |
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291 | } |
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292 | |
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293 | set val [$_field get $axis.max] |
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294 | if {"" != $val && "" != $max} { |
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295 | if {$val < $max} { |
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296 | # tool specified this max -- don't go any higher |
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297 | set max $val |
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298 | } |
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299 | } |
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300 | |
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301 | return [list $min $max] |
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302 | } |
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303 | |
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304 | # ---------------------------------------------------------------------- |
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305 | # USAGE: controls get ?<name>? |
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306 | # USAGE: controls put <path> <value> |
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307 | # |
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308 | # Returns a list {path1 x1 y1 val1 path2 x2 y2 val2 ...} representing |
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309 | # control points for the specified field component <name>. |
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310 | # ---------------------------------------------------------------------- |
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311 | itcl::body Rappture::Field::controls {option args} { |
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312 | switch -- $option { |
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313 | get { |
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314 | set what [lindex $args 0] |
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315 | if {[info exists _comp2cntls($what)]} { |
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316 | return $_comp2cntls($what) |
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317 | } |
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318 | return "" |
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319 | } |
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320 | put { |
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321 | set path [lindex $args 0] |
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322 | set value [lindex $args 1] |
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323 | $_xmlobj put $path.current $value |
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324 | _build |
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325 | } |
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326 | default { |
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327 | error "bad option \"$option\": should be get or put" |
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328 | } |
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329 | } |
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330 | } |
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331 | |
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332 | # ---------------------------------------------------------------------- |
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333 | # USAGE: hints ?<keyword>? |
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334 | # |
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335 | # Returns a list of key/value pairs for various hints about plotting |
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336 | # this field. If a particular <keyword> is specified, then it returns |
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337 | # the hint for that <keyword>, if it exists. |
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338 | # ---------------------------------------------------------------------- |
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339 | itcl::body Rappture::Field::hints {{keyword ""}} { |
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340 | foreach {key path} { |
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341 | group about.group |
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342 | label about.label |
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343 | color about.color |
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344 | style about.style |
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345 | scale about.scale |
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346 | units units |
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347 | } { |
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348 | set str [$_field get $path] |
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349 | if {"" != $str} { |
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350 | set hints($key) $str |
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351 | } |
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352 | } |
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353 | |
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354 | # to be compatible with curve objects |
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355 | set hints(xlabel) "Position" |
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356 | |
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357 | if {[info exists hints(group)] && [info exists hints(label)]} { |
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358 | # pop-up help for each curve |
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359 | set hints(tooltip) $hints(label) |
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360 | } |
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361 | |
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362 | if {$keyword != ""} { |
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363 | if {[info exists hints($keyword)]} { |
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364 | return $hints($keyword) |
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365 | } |
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366 | return "" |
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367 | } |
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368 | return [array get hints] |
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369 | } |
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370 | |
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371 | # ---------------------------------------------------------------------- |
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372 | # USAGE: _build |
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373 | # |
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374 | # Used internally to build up the vector representation for the |
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375 | # field when the object is first constructed, or whenever the field |
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376 | # data changes. Discards any existing vectors and builds everything |
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377 | # from scratch. |
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378 | # ---------------------------------------------------------------------- |
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379 | itcl::body Rappture::Field::_build {} { |
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380 | # discard any existing data |
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381 | foreach name [array names _comp2xy] { |
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382 | eval blt::vector destroy $_comp2xy($name) |
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383 | } |
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384 | foreach name [array names _comp2vtk] { |
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385 | set mobj [lindex $_comp2vtk($name) 0] |
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386 | set class [$mobj info class] |
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387 | ${class}::release $mobj |
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388 | |
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389 | set fobj [lindex $_comp2vtk($name) 1] |
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390 | rename $fobj "" |
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391 | } |
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392 | catch {unset _comp2xy} |
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393 | catch {unset _comp2vtk} |
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394 | catch {unset _comp2dims} |
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395 | catch {unset _comp2style} |
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396 | |
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397 | # |
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398 | # Scan through the components of the field and create |
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399 | # vectors for each part. |
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400 | # |
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401 | foreach cname [$_field children -type component] { |
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402 | set type "" |
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403 | if {( [$_field element $cname.constant] != "" |
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404 | && [$_field element $cname.domain] != "" ) |
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405 | || [$_field element $cname.xy] != ""} { |
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406 | set type "1D" |
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407 | } elseif {[$_field element $cname.mesh] != "" |
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408 | && [$_field element $cname.values] != ""} { |
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409 | set type "points-on-mesh" |
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410 | } elseif {[$_field element $cname.vtk] != ""} { |
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411 | set type "vtk" |
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412 | } |
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413 | |
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414 | set _comp2style($cname) "" |
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415 | |
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416 | if {$type == "1D"} { |
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417 | # |
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418 | # 1D data can be represented as 2 BLT vectors, |
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419 | # one for x and the other for y. |
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420 | # |
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421 | set xv "" |
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422 | set yv "" |
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423 | |
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424 | set val [$_field get $cname.constant] |
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425 | if {$val != ""} { |
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426 | set domain [$_field get $cname.domain] |
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427 | if {$domain == "" || ![info exists _limits($domain)]} { |
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428 | set z0 0 |
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429 | set z1 $_zmax |
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430 | } else { |
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431 | foreach {z0 z1} $_limits($domain) { break } |
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432 | } |
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433 | set xv [blt::vector create x$_counter] |
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434 | $xv append $z0 $z1 |
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435 | |
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436 | foreach {val pcomp} [_getValue $val] break |
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437 | set yv [blt::vector create y$_counter] |
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438 | $yv append $val $val |
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439 | |
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440 | if {$pcomp != ""} { |
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441 | set zm [expr {0.5*($z0+$z1)}] |
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442 | set _comp2cntls($cname) \ |
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443 | [list $pcomp $zm $val "$val$_units"] |
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444 | } |
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445 | } else { |
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446 | set xydata [$_field get $cname.xy] |
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447 | if {"" != $xydata} { |
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448 | set xv [blt::vector create x$_counter] |
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449 | set yv [blt::vector create y$_counter] |
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450 | |
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451 | foreach line [split $xydata \n] { |
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452 | if {[scan $line {%g %g} xval yval] == 2} { |
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453 | $xv append $xval |
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454 | $yv append $yval |
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455 | } |
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456 | } |
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457 | } |
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458 | } |
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459 | |
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460 | if {$xv != "" && $yv != ""} { |
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461 | # sort x-coords in increasing order |
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462 | $xv sort $yv |
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463 | |
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464 | set _comp2dims($cname) "1D" |
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465 | set _comp2xy($cname) [list $xv $yv] |
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466 | incr _counter |
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467 | } |
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468 | } elseif {$type == "points-on-mesh"} { |
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469 | # |
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470 | # More complex 2D/3D data is represented by a mesh |
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471 | # object and an associated vtkFloatArray for field |
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472 | # values. |
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473 | # |
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474 | set path [$_field get $cname.mesh] |
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475 | if {[$_xmlobj element $path] != ""} { |
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476 | switch -- [$_xmlobj element -as type $path] { |
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477 | cloud { |
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478 | set mobj [Rappture::Cloud::fetch $_xmlobj $path] |
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479 | } |
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480 | mesh { |
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481 | set mobj [Rappture::Mesh::fetch $_xmlobj $path] |
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482 | } |
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483 | } |
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484 | |
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485 | if {[$mobj dimensions] > 1} { |
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486 | # |
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487 | # 2D/3D data |
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488 | # Store cloud/field as components |
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489 | # |
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490 | set values [$_field get $cname.values] |
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491 | set farray [vtkFloatArray ::vals$_counter] |
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492 | |
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493 | foreach v $values { |
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494 | if {"" != $_units} { |
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495 | set v [Rappture::Units::convert $v \ |
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496 | -context $_units -to $_units -units off] |
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497 | } |
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498 | $farray InsertNextValue $v |
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499 | } |
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500 | |
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501 | set _comp2dims($cname) "[$mobj dimensions]D" |
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502 | set _comp2vtk($cname) [list $mobj $farray] |
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503 | set _comp2style($cname) [$_field get $cname.style] |
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504 | incr _counter |
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505 | } else { |
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506 | # |
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507 | # OOPS! This is 1D data |
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508 | # Forget the cloud/field -- store BLT vectors |
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509 | # |
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510 | set xv [blt::vector create x$_counter] |
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511 | set yv [blt::vector create y$_counter] |
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512 | |
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513 | set vtkpts [$mobj points] |
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514 | set max [$vtkpts GetNumberOfPoints] |
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515 | for {set i 0} {$i < $max} {incr i} { |
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516 | set xval [lindex [$vtkpts GetPoint $i] 0] |
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517 | $xv append $xval |
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518 | } |
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519 | set class [$mobj info class] |
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520 | ${class}::release $mobj |
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521 | |
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522 | set values [$_field get $cname.values] |
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523 | foreach yval $values { |
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524 | if {"" != $_units} { |
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525 | set yval [Rappture::Units::convert $yval \ |
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526 | -context $_units -to $_units -units off] |
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527 | } |
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528 | $yv append $yval |
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529 | } |
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530 | |
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531 | # sort x-coords in increasing order |
---|
532 | $xv sort $yv |
---|
533 | |
---|
534 | set _comp2dims($cname) "1D" |
---|
535 | set _comp2xy($cname) [list $xv $yv] |
---|
536 | incr _counter |
---|
537 | } |
---|
538 | } else { |
---|
539 | puts "WARNING: can't find mesh $path for field component" |
---|
540 | } |
---|
541 | } elseif {$type == "vtk"} { |
---|
542 | # |
---|
543 | # Extract native vtk data from the XML and use a reader |
---|
544 | # to load it. |
---|
545 | # |
---|
546 | vtkRectilinearGridReader $this-gr |
---|
547 | $this-gr SetInputString [$_field get $cname.vtk] |
---|
548 | |
---|
549 | |
---|
550 | set _comp2dims($cname) "[$mobj dimensions]D" |
---|
551 | set _comp2vtk($cname) [list $mobj $farray] |
---|
552 | set _comp2style($cname) [$_field get $cname.style] |
---|
553 | incr _counter |
---|
554 | } |
---|
555 | } |
---|
556 | } |
---|
557 | |
---|
558 | # ---------------------------------------------------------------------- |
---|
559 | # USAGE: _getValue <expr> |
---|
560 | # |
---|
561 | # Used internally to get the value for an expression <expr>. Returns |
---|
562 | # a list of the form {val parameterPath}, where val is the numeric |
---|
563 | # value of the expression, and parameterPath is the XML path to the |
---|
564 | # parameter representing the value, or "" if the <expr> does not |
---|
565 | # depend on any parameters. |
---|
566 | # ---------------------------------------------------------------------- |
---|
567 | itcl::body Rappture::Field::_getValue {expr} { |
---|
568 | # |
---|
569 | # First, look for the expression among the <parameter>'s |
---|
570 | # associated with the device. |
---|
571 | # |
---|
572 | set found 0 |
---|
573 | foreach pcomp [$_xmlobj children parameters] { |
---|
574 | set id [$_xmlobj element -as id parameters.$pcomp] |
---|
575 | if {[string equal $id $expr]} { |
---|
576 | set val [$_xmlobj get parameters.$pcomp.current] |
---|
577 | if {"" == $val} { |
---|
578 | set val [$_xmlobj get parameters.$pcomp.default] |
---|
579 | } |
---|
580 | if {"" != $val} { |
---|
581 | set expr $val |
---|
582 | set found 1 |
---|
583 | break |
---|
584 | } |
---|
585 | } |
---|
586 | } |
---|
587 | if {$found} { |
---|
588 | set pcomp "parameters.$pcomp" |
---|
589 | } else { |
---|
590 | set pcomp "" |
---|
591 | } |
---|
592 | |
---|
593 | if {$_units != ""} { |
---|
594 | set expr [Rappture::Units::convert $expr \ |
---|
595 | -context $_units -to $_units -units off] |
---|
596 | } |
---|
597 | |
---|
598 | return [list $expr $pcomp] |
---|
599 | } |
---|