Process SMIL directives in XML data

From Rosetta Code
(Redirected from Load animated 3D data)
Process SMIL directives in XML data is a draft programming task. It is not yet considered ready to be promoted as a complete task, for reasons that should be found in its talk page.

In order to represent evolutions of contents over time, the SMIL standard provides a solution to record the animation of data. Smil animations can be added to any kind of contents formated in XML.

The task is to create an utility that given the first Smiled XML file, would return the following ones:

<?xml version="1.0" ?>
<smil>
<X3D>
  <Scene>
    <Viewpoint position="0 0 8" orientation="0 0 1 0"/>
    <PointLight color='1 1 1' location='0 2 0'/>
    <Shape>
      <Box size='2 1 2'>
        <animate attributeName="size" from="2 1 2"
                                        to="1 2 1" begin="0s" dur="10s"/>
      </Box>
      <Appearance>
        <Material diffuseColor='0.0 0.6 1.0'>
          <animate attributeName="diffuseColor" from="0.0 0.6 1.0"
                                                  to="1.0 0.4 0.0" begin="0s" dur="10s"/>
        </Material>
      </Appearance>
    </Shape>
  </Scene>
</X3D>
</smil>

At t = 0 second here is the expected output:

<?xml version="1.0" ?>
<X3D>
  <Scene>
    <Viewpoint position="0 0 8" orientation="0 0 1 0"/>
    <PointLight color='1 1 1' location='0 2 0'/>
    <Shape>
      <Box size='2 1 2'/>
      <Appearance>
        <Material diffuseColor='0.0 0.6 1.0'/>
      </Appearance>
    </Shape>
  </Scene>
</X3D>

At t = 2 second here is the expected output:

<?xml version="1.0" ?>
<X3D>
  <Scene>
    <Viewpoint position="0 0 8" orientation="0 0 1 0"/>
    <PointLight color='1 1 1' location='0 2 0'/>
    <Shape>
      <Box size='1.8 1.2 1.8'/>
      <Appearance>
        <Material diffuseColor='0.2 0.56 0.8'/>
      </Appearance>
    </Shape>
  </Scene>
</X3D>

Go[edit]

Library: etree
package main

import (
    "fmt"
    "github.com/beevik/etree"
    "log"
    "os"
    "strconv"
    "strings"
)

type animData struct {
    element *etree.Element
    attrib  string
    from    string
    to      string
    begin   float64
    dur     float64
}

func check(err error) {
    if err != nil {
        log.Fatal(err)
    }
}

func (ad *animData) AtTime(t float64) string {
    beg := ad.begin
    end := beg + ad.dur
    if t < beg || t > end {
        log.Fatalf("time must be in interval [%g, %g]", beg, end)
    }
    fromSplit := strings.Fields(ad.from)
    toSplit := strings.Fields(ad.to)
    le := len(fromSplit)
    interSplit := make([]string, le)
    for i := 0; i < le; i++ {
        fromF, err := strconv.ParseFloat(fromSplit[i], 64)
        check(err)
        toF, err := strconv.ParseFloat(toSplit[i], 64)
        check(err)
        interF := (fromF*(end-t) + toF*(t-beg)) / ad.dur
        interSplit[i] = fmt.Sprintf("%.2f", interF)
    }
    return strings.Join(interSplit, " ")
}

func main() {
    doc := etree.NewDocument()
    check(doc.ReadFromFile("smil.xml"))
    smil := doc.SelectElement("smil")
    if smil == nil {
        log.Fatal("'smil' element not found")
    }
    x3d := smil.SelectElement("X3D")
    if x3d == nil {
        log.Fatal("'X3D' element not found")
    }
    doc.SetRoot(x3d) // remove 'smil' element
    var ads []*animData
    for _, a := range doc.FindElements("//animate") {
        attrib := a.SelectAttrValue("attributeName", "?")
        from := a.SelectAttrValue("from", "?")
        to := a.SelectAttrValue("to", "?")
        beginS := a.SelectAttrValue("begin", "?")
        durS := a.SelectAttrValue("dur", "?")
        if attrib == "?" || from == "?" || to == "?" ||
            beginS == "?" || durS == "?" {
            log.Fatal("an animate element has missing attribute(s)")
        }
        begin, err := strconv.ParseFloat(beginS[:len(beginS)-1], 64)
        check(err)
        dur, err := strconv.ParseFloat(durS[:len(durS)-1], 64)
        check(err)
        p := a.Parent()
        if p == nil {
            log.Fatal("an animate element has no parent")
        }
        pattrib := p.SelectAttrValue(attrib, "?")
        if pattrib == "?" {
            log.Fatal("an animate element's parent has missing attribute")
        }
        ads = append(ads, &animData{p, attrib, from, to, begin, dur})
        p.RemoveChild(a) // remove 'animate' element
    }
    ts := []float64{0, 2}
    for _, t := range ts {
        for _, ad := range ads {
            s := ad.AtTime(t)
            ad.element.CreateAttr(ad.attrib, s)
        }
        doc.Indent(2)
        fmt.Printf("At time = %g seconds:\n\n", t)
        doc.WriteTo(os.Stdout)
        fmt.Println()
    }
}
Output:
At time = 0 seconds:

<?xml version="1.0" ?>
<X3D>
  <Scene>
    <Viewpoint position="0 0 8" orientation="0 0 1 0"/>
    <PointLight color="1 1 1" location="0 2 0"/>
    <Shape>
      <Box size="2.00 1.00 2.00"/>
      <Appearance>
        <Material diffuseColor="0.00 0.60 1.00"/>
      </Appearance>
    </Shape>
  </Scene>
</X3D>

At time = 2 seconds:

<?xml version="1.0" ?>
<X3D>
  <Scene>
    <Viewpoint position="0 0 8" orientation="0 0 1 0"/>
    <PointLight color="1 1 1" location="0 2 0"/>
    <Shape>
      <Box size="1.80 1.20 1.80"/>
      <Appearance>
        <Material diffuseColor="0.20 0.56 0.80"/>
      </Appearance>
    </Shape>
  </Scene>
</X3D>

Nim[edit]

import sequtils, strformat, strtabs, strutils, xmlparser, xmltree

type

  Animation = object
    attrName: string          # Attribute to animate.
    fromValues: seq[float]    # List of "from" values.
    toValues: seq[float]      # List of "to" values.
    begin: float              # Animation starting time.
    duration: float           # Animation duration.


func getAnim(node: XmlNode): Animation =
  ## Build an animation object from an XML node.

  result.attrName = node.attr("attributeName")
  if result.attrName.len == 0:
    raise newException(ValueError, "missing 'attributeName' attribute")
  var str = node.attr("from")
  if str.len == 0:
    raise newException(ValueError, "missing 'from' attribute")
  result.fromValues = str.splitWhitespace().map(parseFloat)
  str = node.attr("to")
  if str.len == 0:
    raise newException(ValueError, "missing 'to' attribute")
  result.toValues = str.splitWhitespace().map(parseFloat)
  if result.fromValues.len != result.toValues.len:
    raise newException(ValueError, "inconsistent number of values")
  str = node.attr("begin")
  if str.len == 0:
    raise newException(ValueError, "missing 'begin' attribute")
  if str[^1] != 's':
    raise newException(ValueError, "missing unit")
  result.begin = parseFloat(str[0..^2])
  str = node.attr("dur")
  if str.len == 0:
    raise newException(ValueError, "missing 'dur' attribute")
  if str[^1] != 's':
    raise newException(ValueError, "missing unit")
  result.duration = parseFloat(str[0..^2])


func buildXml(node: XmlNode; t: float): XmlNode =
  ## Build the XML tree of a SMIL animation at time "t".

  if node.len > 0 and node[0].tag == "animate":
    # Child is an animate node.
    let anim = node[0].getAnim()
    # Check attribute name.
    if node.attr(anim.attrName).len == 0:
      raise newException(ValueError, &"unable to find attribute '{anim.attrName}'")
    # Check time.
    if t notin anim.begin..(anim.begin + anim.duration):
      raise newException(ValueError, "time value out of range")
    # Build attribute value.
    var aVal = newSeq[float](anim.fromValues.len)
    for i in 0..aVal.high:
      aVal[i] = (anim.fromValues[i] * (anim.begin + anim.duration - t) +
                 anim.toValues[i] * (t - anim.begin)) / anim.duration
    # Set attributes.
    let a = node.attrs
    a[anim.attrName] = aVal.mapIt(it.formatFloat(ffDefault, 2)).join(" ")
    result = newElement(node.tag)
    result.attrs = a

  else:
    # Node child (if any) is not an animate node: copy the node and process children.
    result = newElement(node.tag)
    result.attrs = node.attrs
    for child in node:
      result.add child.buildXml(t)


when isMainModule:
  let smil = loadXml("smil.xml")
  if smil.tag != "smil":
    raise newException(ValueError, "not a SMIL file")
  let newRoot = smil[0]
  echo "At time 0 second:\n"
  echo xmlHeader, newRoot.buildXml(0)
  echo "\nAt time 2 seconds:\n"
  echo xmlHeader, newRoot.buildXml(2)
Output:
At time 0 second:

<?xml version="1.0" encoding="UTF-8" ?>
<X3D>
  <Scene>
    <Viewpoint position="0 0 8" orientation="0 0 1 0" />
    <PointLight color="1 1 1" location="0 2 0" />
    <Shape>
      <Box size="2.0 1.0 2.0" />
      <Appearance>
        <Material diffuseColor="0.0 0.60 1.0" />
      </Appearance>
    </Shape>
  </Scene>
</X3D>

At time 2 seconds:

<?xml version="1.0" encoding="UTF-8" ?>
<X3D>
  <Scene>
    <Viewpoint position="0 0 8" orientation="0 0 1 0" />
    <PointLight color="1 1 1" location="0 2 0" />
    <Shape>
      <Box size="1.8 1.2 1.8" />
      <Appearance>
        <Material diffuseColor="0.20 0.56 0.80" />
      </Appearance>
    </Shape>
  </Scene>
</X3D>

Perl[edit]

Translation of: Raku
# 20201101 added Perl programming solution

use 5.014; # for s///r;
use strict;
use warnings;

BEGIN {
   package Animatee;
   use Moo;
   has [qw(todo begin dur from to)] => ( is => 'rw');
   $INC{"Animatee.pm"} = 1;
}

use Animatee;
use XML::Twig;
use List::AllUtils 'pairwise';

my $smil = <<'DATA';
<?xml version="1.0" ?> <smil><X3D><Scene><Viewpoint position="0 0 8" orientation="0 0 1 0" /><PointLight color="1 1 1" location="0 2 0" /><Shape><Box size="2 1 2"><animate attributeName="size" from="2 1 2" to="1 2 1" begin="0s" dur="10s" /></Box><Appearance><Material diffuseColor="0.0 0.6 1.0"><animate attributeName="diffuseColor" from="0.0 0.6 1.0" to="1.0 0.4 0.0" begin="0s" dur="10s" /></Material></Appearance></Shape></Scene></X3D></smil>
DATA

my %Parents;

my $x = XML::Twig->new->parse($smil);

for my $node ($x->findnodes("//animate"))  {

   my $y = $node->parent;
   exists($Parents{$y}) ? (die) : ($Parents{my $k = $y->getName} = Animatee->new);
   for my $animatee ($y->getChildNodes)  {
      my %h = %{$animatee->atts};
      $Parents{$k}->todo($h{attributeName});
      $Parents{$k}->from([ split(/\s+/,$h{from}) ]);
      $Parents{$k}->to([ split(/\s+/,$h{to}) ]);
      $Parents{$k}->begin( $h{begin} =~ m/\d+/g);
      $Parents{$k}->dur  ( $h{dur}   =~ m/\d+/g);
   }
}

my $z =  XML::Twig->new->parse($smil =~ s/\<\/?smil\>//gr) or die;

for my $t ( 0, 2, 4 ) {
   my $clone = $z;
   while ( my( $k,$v ) = each %Parents) {
      my @incre = pairwise { ($a-$b)/$v->dur } @{$v->to}, @{$v->from};
      for my $f ($clone->findnodes("//$k")) {
         my $c = join (' ', pairwise { $a+$b*$t } @{$v->from}, @incre);
         $f->set_att($v->todo,$c);
      }
      for my $f ($clone->findnodes("//animate")) {
         $f->delete
      }
   }
   print "when t = $t\n";
   print $clone->sprint,"\n";
}
Output:
when t = 0
<?xml version="1.0"?>
<X3D><Scene><Viewpoint orientation="0 0 1 0" position="0 0 8"/><PointLight color="1 1 1" location="0 2 0"/><Shape><Box size="2 1 2"></Box><Appearance><Material diffuseColor="0 0.6 1"></Material></Appearance></Shape></Scene></X3D>
when t = 2
<?xml version="1.0"?>
<X3D><Scene><Viewpoint orientation="0 0 1 0" position="0 0 8"/><PointLight color="1 1 1" location="0 2 0"/><Shape><Box size="1.8 1.2 1.8"></Box><Appearance><Material diffuseColor="0.2 0.56 0.8"></Material></Appearance></Shape></Scene></X3D>
when t = 4
<?xml version="1.0"?>
<X3D><Scene><Viewpoint orientation="0 0 1 0" position="0 0 8"/><PointLight color="1 1 1" location="0 2 0"/><Shape><Box size="1.6 1.4 1.6"></Box><Appearance><Material diffuseColor="0.4 0.52 0.6"></Material></Appearance></Shape></Scene></X3D>

Phix[edit]

with javascript_semantics
include builtins\xml.e
 
constant xml = """
<?xml version="1.0" ?>
<smil>
<X3D>
  <Scene>
    <Viewpoint position="0 0 8" orientation="0 0 1 0"/>
    <PointLight color='1 1 1' location='0 2 0'/>
    <Shape>
      <Box size='2 1 2'>
        <animate attributeName="size" from="2 1 2"
                                        to="1 2 1" begin="0s" dur="10s"/>
      </Box>
      <Appearance>
        <Material diffuseColor='0.0 0.6 1.0'>
          <animate attributeName="diffuseColor" from="0.0 0.6 1.0"
                                                  to="1.0 0.4 0.0" begin="0s" dur="10s"/>
        </Material>
      </Appearance>
    </Shape>
  </Scene>
</X3D>
</smil>
"""
 
function animate_contents(sequence doc, atom t)
    doc = deep_copy(doc)
    sequence a = xml_get_nodes(doc,"animate")
    if a={} then
        for i=1 to length(doc[XML_CONTENTS]) do
            doc[XML_CONTENTS][i] = animate_contents(doc[XML_CONTENTS][i],t)
        end for
    else
        for i=1 to length(doc[XML_CONTENTS]) do
            if doc[XML_CONTENTS][i][XML_TAGNAME]="animate" then
                string name = xml_get_attribute(doc[XML_CONTENTS][i],"attributeName"),
                       vfrm = xml_get_attribute(doc[XML_CONTENTS][i],"from"),
                       v_to = xml_get_attribute(doc[XML_CONTENTS][i],"to"),
                       sbeg = xml_get_attribute(doc[XML_CONTENTS][i],"begin"),
                       sdur = xml_get_attribute(doc[XML_CONTENTS][i],"dur")
                sequence from = apply(split(vfrm),to_number),
                         to_s = apply(split(v_to),to_number)
                atom begin = to_number(trim_tail(sbeg,"s")),
                     durat = to_number(trim_tail(sdur,"s")),
                     fj = begin+durat-t,
                     tj = t-begin
                -- plenty more error handling possible here...
                if tj<0 or fj<0 or length(from)!=length(to_s) then ?9/0 end if
                for j=1 to length(from) do
                    from[j] = sprintf("%.2f",(from[j]*fj+to_s[j]*tj)/durat)
                end for
                doc = xml_set_attribute(doc,name,join(from," "))
                doc[XML_CONTENTS][i..i] = "" -- remove 'animate'
                exit
            end if
        end for
    end if
    return doc
end function
 
function animate(sequence doc, atom t)
    doc = deep_copy(doc)
    doc[XML_CONTENTS] = doc[XML_CONTENTS][XML_CONTENTS][1]  -- remove smil
    doc[XML_CONTENTS] = animate_contents(doc[XML_CONTENTS],t)
    return doc
end function
 
sequence doc = xml_parse(xml)
if doc[XML_DOCUMENT]!="document"
or doc[XML_CONTENTS][XML_TAGNAME]!="smil"
or length(doc[XML_CONTENTS][XML_CONTENTS])!=1
or doc[XML_CONTENTS][XML_CONTENTS][1][XML_TAGNAME]!="X3D" then
    ?9/0
end if
printf(1,"At time = 0:\n\n")
puts(1,xml_sprint(animate(doc,0)))
printf(1,"\nAt time = 2:\n\n")
puts(1,xml_sprint(animate(doc,2)))
Output:
At time = 0:

<?xml version="1.0" ?>
<X3D>
  <Scene>
    <Viewpoint position="0 0 8" orientation="0 0 1 0" />
    <PointLight color="1 1 1" location="0 2 0" />
    <Shape>
      <Box size="2.00 1.00 2.00" />
      <Appearance>
        <Material diffuseColor="0.00 0.60 1.00" />
      </Appearance>
    </Shape>
  </Scene>
</X3D>

At time = 2:

<?xml version="1.0" ?>
<X3D>
  <Scene>
    <Viewpoint position="0 0 8" orientation="0 0 1 0" />
    <PointLight color="1 1 1" location="0 2 0" />
    <Shape>
      <Box size="1.80 1.20 1.80" />
      <Appearance>
        <Material diffuseColor="0.20 0.56 0.80" />
      </Appearance>
    </Shape>
  </Scene>
</X3D>

Raku[edit]

(formerly Perl 6) A crude attempt that only works with task data.

use XML::XPath;

my $smil = q:to<DATA>; # cramped verison, modified from task data
<?xml version="1.0" ?> <smil><X3D><Scene><Viewpoint position="0 0 8" orientation="0 0 1 0" /><PointLight color="1 1 1" location="0 2 0" /><Shape><Box size="2 1 2"><animate attributeName="size" from="2 1 2" to="1 2 1" begin="0s" dur="10s" /></Box><Appearance><Material diffuseColor="0.0 0.6 1.0"><animate attributeName="diffuseColor" from="0.0 0.6 1.0" to="1.0 0.4 0.0" begin="0s" dur="10s" /></Material></Appearance></Shape></Scene></X3D></smil>
DATA

class Animatee { has ($.todo, @.from, @.to, $.begin, $.dur) is rw };

my %Parents; # keys store the parent tags that got <animate> child

my $x = XML::XPath.new(xml => $smil) or die;

for @($x.find("//animate")) { # strangely need .List or @ coercion to work
   my $y = .parent.name;
   %Parents{$y}:exists ?? die() !! %Parents{$y} = Animatee.new; # unique only
   for .parent.elements {
      %Parents{$y}.todo  = .attribs<attributeName>;
      %Parents{$y}.from  = .attribs<from>.split(/\s+/);
      %Parents{$y}.to    = .attribs<to>.split(/\s+/);
      %Parents{$y}.begin = .attribs<begin>.match(/\d+/);
      %Parents{$y}.dur   = .attribs<dur>.match(/\d+/);
   }
}

# use regex to strip SMIL tag and create a master template; sub-optimal approach
my $z = XML::XPath.new(xml => $smil.subst(/\<\/?smil\>/,'',:g:ii:ss)) or die;

for 0, 2, 4 -> $t { # task requires 0 & 2 only
   my $clone = $z.clone; # work on a copy
   for %Parents.kv -> $k,$v {
      my @incre = ($v.to »-« $v.from) »/» $v.dur; # increment list
      with $clone.find("//$k") { # moving attribute = @from + @increment*$t
         .attribs{%Parents{$_.name}.todo} = $v.from »+« @incre »*» $t;
         .removeChild($_); #  ditch <animate> and friends
      }
   }
   say "when t = ", $t;
   say $clone.find("/");
}
Output:
when t = 0
<?xml version="1.0"?><X3D><Scene><Viewpoint position="0 0 8" orientation="0 0 1 0"/><PointLight location="0 2 0" color="1 1 1"/><Shape><Box size="2 1 2"/><Appearance><Material diffuseColor="0 0.6 1"/></Appearance></Shape></Scene></X3D>
when t = 2
<?xml version="1.0"?><X3D><Scene><Viewpoint position="0 0 8" orientation="0 0 1 0"/><PointLight location="0 2 0" color="1 1 1"/><Shape><Box size="1.8 1.2 1.8"/><Appearance><Material diffuseColor="0.2 0.56 0.8"/></Appearance></Shape></Scene></X3D>
when t = 4
<?xml version="1.0"?><X3D><Scene><Viewpoint position="0 0 8" orientation="0 0 1 0"/><PointLight location="0 2 0" color="1 1 1"/><Shape><Box size="1.6 1.4 1.6"/><Appearance><Material diffuseColor="0.4 0.52 0.6"/></Appearance></Shape></Scene></X3D>

Tcl[edit]

Works with: Tcl version 8.6
Library: tDOM
package require Tcl 8.6
package require tdom

# Applies a time-based interpolation to generate a space-separated list
proc interpolate {time info} {
    dict with info {
	scan $begin "%fs" begin
	scan $dur "%fs" dur
    }
    if {$time < $begin} {
	return $from
    } elseif {$time > $begin+$dur} {
	return $to
    }
    set delta [expr {($time - $begin) / $dur}]
    return [lmap f $from t $to {expr {$f + ($t-$f)*$delta}}]
}

# Applies SMIL <transform> elements to their container
proc applySMILtransform {sourceDocument time} {
    set doc [dom parse [$sourceDocument asXML]]
    foreach smil [$doc selectNodes //smil] {
	foreach context [$smil selectNodes {//*[animate]}] {
	    set animator [$context selectNodes animate]
	    set animated [$context selectNodes @[$animator @attributeName]]
	    $context removeChild $animator
	    $context setAttribute [$animator @attributeName] \
		[interpolate $time [lindex [$animator asList] 1]]
	}
	if {[$smil parentNode] eq ""} {
	    set reparent 1
	} else {
	    [$smil parentNode] replaceChild $smil [$smil firstChild]
	}
    }
    if {[info exist reparent]} {
	set doc [dom parse [[$smil firstChild] asXML]]
    }
    return $doc
}

set t [expr {[lindex $argv 0] + 0.0}]
set result [applySMILtransform [dom parse [read stdin]] $t]
puts {<?xml version="1.0" ?>}
puts -nonewline [$result asXML -indent 2]
Demonstration:

Note that input.smil contains the source document from the task description.

$ tclsh8.6 applySmil.tcl 0 < input.smil
<?xml version="1.0" ?>
<X3D>
  <Scene>
    <Viewpoint position="0 0 8" orientation="0 0 1 0"/>
    <PointLight color="1 1 1" location="0 2 0"/>
    <Shape>
      <Box size="2.0 1.0 2.0"/>
      <Appearance>
        <Material diffuseColor="0.0 0.6 1.0"/>
      </Appearance>
    </Shape>
  </Scene>
</X3D>
$ tclsh8.6 applySmil.tcl 2 < input.smil
<?xml version="1.0" ?>
<X3D>
  <Scene>
    <Viewpoint position="0 0 8" orientation="0 0 1 0"/>
    <PointLight color="1 1 1" location="0 2 0"/>
    <Shape>
      <Box size="1.8 1.2 1.8"/>
      <Appearance>
        <Material diffuseColor="0.2 0.5599999999999999 0.8"/>
      </Appearance>
    </Shape>
  </Scene>
</X3D>

Wren[edit]

Library: Wren-pattern

As Wren lacks any kind of XML support (let alone SMIL), I've had to resort to string parsing to complete this task.

import "/pattern" for Pattern

var xml = """
<?xml version="1.0" ?>
<smil>
<X3D>
  <Scene>
    <Viewpoint position="0 0 8" orientation="0 0 1 0"/>
    <PointLight color='1 1 1' location='0 2 0'/>
    <Shape>
      <Box size='2 1 2'>
        <animate attributeName="size" from="2 1 2"
                                        to="1 2 1" begin="0s" dur="10s"/>
      </Box>
      <Appearance>
        <Material diffuseColor='0.0 0.6 1.0'>
          <animate attributeName="diffuseColor" from="0.0 0.6 1.0"
                                                  to="1.0 0.4 0.0" begin="0s" dur="10s"/>
        </Material>
      </Appearance>
    </Shape>
  </Scene>
</X3D>
</smil>
"""

var extractValue = Fn.new { |s| s.replace("\"", "").split("=")[1] }

var interpolate = Fn.new { |from, to, begin, dur, t|
    if (begin >= t) return from
    if (begin + t >= dur) return to
    var mid = List.filled(3, 0)
    for (i in 0..2) {
        mid[i] = (from[i] * (dur - t) + to[i] * (t - begin)) / (dur - begin)
    }
    return mid
}

var smil = xml.indexOf("smil") > -1
if (!smil) {
    System.print(xml)
    return
}
xml = xml.replace("<smil>\n", "").replace("\n</smil>", "")
var animate = Pattern.new("<animate +1^///>")
var matches = animate.findAll(xml)
var mcount = matches.count
if (mcount == 0) {
    System.print(xml)
    return
}

var elem  = List.filled(mcount, null)
var attr  = List.filled(mcount, null)
var from  = List.filled(mcount, null)
var to    = List.filled(mcount, null)
var begin = List.filled(mcount, 0)
var dur   = List.filled(mcount, 0)
for (i in 0...mcount) {
    var match = matches[i]
    xml = xml.replace(match.text + "\n", "")
    var p = Pattern.new("+1/s")
    var items = p.splitAll(match.text[1..-3])
    attr[i] = extractValue.call(items[1])
    from[i] = [0] * 3
    from[i][0] = Num.fromString(items[2].replace("from=\"", ""))
    from[i][1] = Num.fromString(items[3])
    from[i][2] = Num.fromString(items[4].replace("\"", ""))
    to[i] = [0] * 3
    to[i][0] = Num.fromString(items[5].replace("to=\"", ""))
    to[i][1] = Num.fromString(items[6])
    to[i][2] = Num.fromString(items[7].replace("\"", ""))
    begin[i] = Num.fromString(extractValue.call(items[8]).replace("s", ""))
    dur[i]   = Num.fromString(extractValue.call(items[9]).replace("s", ""))
    p = Pattern.new("<[+1/w] %(attr[i])/='[+1^']'>")
    var matches2 = p.find(xml)
    elem[i] = matches2.capsText[0]
    p = Pattern.new(">\n+1/s<//%(elem[i])>")
    xml = p.replaceAll(xml, "/>")
}

for (t in [0, 2]) {
    var xml2 = xml
    for (i in 0...mcount) {
        var p = Pattern.new("<%(elem[i]) %(attr[i])/='[+1^']'//>")
        var sfrom = p.find(xml2).capsText[0]
        var mid = interpolate.call(from[i], to[i], begin[i], dur[i], t)
        var smid = mid.map { |n| n.toString }.join(" ")
        xml2 = xml2.replace("<%(elem[i]) %(attr[i])='%(sfrom)'/>", "<%(elem[i]) %(attr[i])='%(smid)'/>")
    }
    System.print("At t = %(t) seconds:\n")
    System.print(xml2)
    System.print()
}
Output:
At t = 0 seconds:

<?xml version="1.0" ?>
<X3D>
  <Scene>
    <Viewpoint position="0 0 8" orientation="0 0 1 0"/>
    <PointLight color='1 1 1' location='0 2 0'/>
    <Shape>
      <Box size='2 1 2'/>
      <Appearance>
        <Material diffuseColor='0 0.6 1'/>
      </Appearance>
    </Shape>
  </Scene>
</X3D>

At t = 2 seconds:

<?xml version="1.0" ?>
<X3D>
  <Scene>
    <Viewpoint position="0 0 8" orientation="0 0 1 0"/>
    <PointLight color='1 1 1' location='0 2 0'/>
    <Shape>
      <Box size='1.8 1.2 1.8'/>
      <Appearance>
        <Material diffuseColor='0.2 0.56 0.8'/>
      </Appearance>
    </Shape>
  </Scene>
</X3D>