fix: Transformation nodes must create new scope

In VRML 1, transformations like translations and rotations
  accumulate within a scope as they are encountered, and one
  can even have multiple translations with shapes interleaved
  between them. This accumulation is not possible in VRML97.
  Therefore, it's necessary to insert new scopes in the translated
  file every time a new transformation is encountered. This
  commit makes sure that happens.

package.json5

@@ -1,6 +1,6 @@
 {
   name: 'vrml1to97',
-  version: '0.3.1',
+  version: '0.3.2',
   description: 'JavaScript converter from VRML 1 to VRML97',
   scripts: {
     test: 'echo "Error: no test specified" && exit 1',

src/index.civet

@@ -91,6 +91,7 @@ function addWorldParameter(name: string, value: string, tree: Tree): void
 matches := (str: string, pat: RegExp) => pat.test(str)
 operator matches
 GroupNode := /(?:Transform)?Separator|Group|Switch|WWWAnchor/
+TransformNode := /^(?:Rotation|Scale|Transform|Translation)$/
 SetNode := /IndexedFaceSet|IndexedLineSet|PointSet/
 LightNode := /Light$/
 
@@ -161,6 +162,8 @@ function parse(stream: Lexer, tree: DefTree = {}): DefTree
                switch role
                   matches GroupNode
                      role = 'Child'
+                  matches TransformNode
+                     role = 'Transform'
                   'ShapeHints'
                      role = 'Dummy' // will fill in when we parse the ShapeHints
                   'Coordinate3'
@@ -193,6 +196,19 @@ function parse(stream: Lexer, tree: DefTree = {}): DefTree
                      addChild clause, tree
                   'Shape'
                      addShape clause, [], tree
+                  'Transform'
+                     // VRML97 doesn't allow just the transform part of
+                     // a Transform to be USEd (the whole node must be), so
+                     // we have to recreate the transform. FIXME: dedupe code
+                     content := known[next.value][1..]
+                     {children, ...context} := tree
+                     restOfTree := parse stream, context
+                     if remainingKids := restOfTree.children
+                        newChild := `Transform {\n   ${renderList content}\n   `
+                           + `children [\n      ${renderList remainingKids}`
+                           + "] }\n"
+                        addChild newChild, tree
+                     return tree
                   {}
                      mergeTree role, tree
                   else
@@ -203,20 +219,24 @@ function parse(stream: Lexer, tree: DefTree = {}): DefTree
          {ht: 'word', nt: 'obrace'}
             switch held.value
                matches GroupNode
-                  parent :=
-                     held.value.endsWith('Separator') ? 'Transform' : 'Group'
-                  {children, Translation, Rotation, ...context} := tree
+                  {children, ...context} := tree
                   subTree := parse stream, context
                   if newKids := subTree.children
-                     newChild .= `${parent} {\n   `
-                     if 'Rotation' in subTree
-                        newChild += renderList subTree.Rotation
-                        newChild += "\n   "
-                     if 'Translation' in subTree
-                        newChild += renderList subTree.Translation
-                        newChild += "\n   "
-                     newChild += `children [\n      ${renderList newKids} ] }\n`
+                     newChild :=
+                        `Group { children [\n   ${renderList newKids} ] }\n`
                      addChild newChild, tree
+               matches TransformNode
+                  content := toksUntilClose stream
+                  if (lastDefinition
+                      and tree._definitions?[lastDefinition][0] is 'Transform')
+                     tree._definitions[lastDefinition].push ...content
+                  {children, ...context} := tree
+                  restOfTree := parse stream, context
+                  if remainingKids := restOfTree.children
+                     newChild := `Transform {\n   ${renderList content}\n   `
+                        + `children [\n      ${renderList remainingKids} ] }\n`
+                     addChild newChild, tree
+                  return tree // used the rest of the tree, so done
                'ShapeHints'
                   subTree := parse stream
                   hints: Tree := {}
@@ -228,10 +248,6 @@ function parse(stream: Lexer, tree: DefTree = {}): DefTree
                   mergeTree hints, tree
                   if lastDefinition and tree._definitions
                      tree._definitions[lastDefinition] = [hints]
-               'Rotation'
-                  tree.Rotation = toksUntilClose stream
-               'Translation'
-                  tree.Translation = toksUntilClose stream
                'Coordinate3'
                   tree.Coordinate = toksUntilClose stream
                'Normal'