Handle locale for MaterialX inputs (#1178)

For MaterialX let's assume we have a xml with `<input name="diffColor" type="vector3" value="1,1.5,2.0"/>`
mx:Vector3(1,1.5,2.0) should be interpreted as float[3] = [1.0f, 1.5f, 2.0f]. But based on the locale settings, 1,1.5 will be parsed as a value. By setting the locale on std::stringstream we ensure that input values are correctly read 
Some background reference around this https://stdcxx.apache.org/doc/stdlibug/24-3.html
https://docs.microsoft.com/en-us/globalization/locale/number-formatting
Partially addresses Issue #1183

Other changes:
Basic utility to generate a json and hpp export from MaterialX nodedef
e.g. given a node def e.g. ND_standard_surface_surfaceshader will
     generate a standard_surface.json and standard_surface.hpp
The hpp/json can be used for simple reflection instead of parsing mtlx libraries

resources/Materials/TestSuite/locale/numericformat.mtlx

@@ -0,0 +1,12 @@
+<?xml version="1.0"?>
+<materialx version="1.38" cms="ocio" colorspace="lin_rec709">
+  <nodedef name="ND_simple_srf_surface" node="simple_srf">
+    <input name="diffColor" type="color3" value="0.18,0.18, 0.18"/>
+    <input name="specColor" type="color3" value="0.05, 0.05,0.05" />
+    <input name="normal" type="vector3" value="1,0.5,1" />
+    <input name="specRoughness" type="float" value="0.25" />
+    <input name="intensity" type="integer" value="-1" />
+    <output name="out" type="surfaceshader" />
+  </nodedef>
+  <implementation name="IM_simple_srf" nodedef="ND_simple_srf_surface" />
+</materialx>

resources/Materials/TestSuite/locale/utf8.mtlx

@@ -0,0 +1,12 @@
+<?xml version="1.0"?>
+<materialx version="1.38" cms="ocio" colorspace="lin_rec709">
+  <nodedef name="ND_simple_srf_surface" node="simple_srf">
+    <input name="diffColor" type="color3" value="0.18,0.18, 0.18"  uiname="びまん性"/>
+    <input name="specColor" type="color3" value="0.05, 0.05,0.05" uiname="spéculaire"/>
+    <input name="normal" type="vector3" value="1,0.5,1" />
+    <input name="specRoughness" type="float" value="0.25" uiname="表面粗さ"/>
+    <input name="intensity" type="integer" value="-1" />
+    <output name="out" type="surfaceshader" />
+  </nodedef>
+  <implementation name="IM_simple_srf" nodedef="ND_simple_srf_surface" />
+</materialx>

source/MaterialXContrib/Utilities/CMakeLists.txt

@@ -0,0 +1 @@
+install(DIRECTORY "${CMAKE_CURRENT_SOURCE_DIR}/Scripts/" DESTINATION "${CMAKE_INSTALL_PREFIX}/python" MESSAGE_NEVER)

source/MaterialXContrib/Utilities/Scripts/mxnodedefconvert.py

@@ -0,0 +1,275 @@
+#!/usr/bin/env python
+"""
+Utility to generate json and hpp from MaterialX nodedef
+
+Given a node def e.g. ND_standard_surface_surfaceshader will
+generate a standard_surface.json and standard_surface.hpp
+The hpp/json can be used for simple reflection instead
+of parsing mtlx libraries
+"""
+
+import sys
+import os
+import argparse
+import json
+import hashlib
+import MaterialX as mx
+
+INPUTFILEHASH = 0
+mx_stdTypes = {
+    'color3': ['MaterialX::Color3', mx.Color3(1, 1, 1)],
+    'color4': ['MaterialX::Color4', mx.Color4(1, 1, 1, 1)],
+    'vector4': ['MaterialX::Vector4', mx.Vector4(1, 1, 1, 1)],
+    'vector3': ['MaterialX::Vector3', mx.Vector3(1, 1, 1)],
+    'vector2': ['MaterialX::Vector2', mx.Vector2(1, 1)],
+    'matrix33': ['MaterialX::Matrix33', None],
+    'matrix44': ['MaterialX::Matrix44', None],
+    'integerarray': ['std::vector<int>',  None],
+    'floatarray': ['std::vector<float>', None],
+    'color3array': ['std::vector<MaterialX::Color3>', None],
+    'color4array': ['std::vector<MaterialX::Color4>', None],
+    'vector2array': ['std::vector<MaterialX::Vector2>', None],
+    'vector3array': ['std::vector<MaterialX::Vector3>', None],
+    'vector4array': ['std::vector<MaterialX::Vector4>', None],
+    'stringarray': ['std::vector<std::string>', None],
+    'boolean': ['bool', False],
+    'integer': ['int', 0],
+    'file': ['std::string', ""],
+    'filename': ['std::string', ""],
+    'string': ['std::string', ""],
+    'float': ['float', 0],
+
+    #TODO: create custom structs (fixme)
+    'lightshader': ['lightshader', None],
+    'volumeshader': ['volumeshader', None],
+    'displacementshader': ['displacementshader', None],
+    'surfaceshader': ['surfaceshader', None],
+    'BSDF': ['BSDF', None],
+    'EDF': ['EDF', None],
+    'VDF': ['VDF', None],
+}
+
+def _getType(mxType):
+    return mx_stdTypes[mxType][0]
+
+def _getDefault(mxType):
+    return mx_stdTypes[mxType][1]
+
+# Compute gitHash
+def _computeGitHash(mtlxfile):
+    with open(mtlxfile, 'r') as afile:
+        buf = afile.read().encode()
+        hasher = hashlib.sha1()
+        hasher.update(b"blob %u\0" % len(buf))
+        hasher.update(buf)
+        return hasher.hexdigest()
+
+def main():
+    parser = argparse.ArgumentParser(
+        description="MaterialX nodedef to json/hpp converter.")
+    parser.add_argument(dest="inputFilename",
+                        help="Filename of the input document.")
+    parser.add_argument("--node", dest="nodedef", type=str,
+                        help="Node to export")
+    parser.add_argument("--stdlib", dest="stdlib", action="store_true",
+                        help="Import standard MaterialX libraries into the document.")
+    opts = parser.parse_args()
+
+    doc = mx.createDocument()
+    try:
+        mx.readFromXmlFile(doc, opts.inputFilename)
+        # Git hash for tracking source document
+        global INPUTFILEHASH
+        INPUTFILEHASH = _computeGitHash(opts.inputFilename)
+
+    except mx.ExceptionFileMissing as err:
+        print(err)
+        sys.exit(0)
+
+    if opts.stdlib:
+        stdlib = mx.createDocument()
+        filePath = os.path.dirname(os.path.abspath(__file__))
+        searchPath = mx.FileSearchPath(os.path.join(filePath, '..', '..'))
+        searchPath.append(os.path.dirname(opts.inputFilename))
+        libraryFolders = ["libraries"]
+        mx.loadLibraries(libraryFolders, searchPath, stdlib)
+        doc.importLibrary(stdlib)
+
+    (valid, message) = doc.validate()
+    if valid:
+        print("%s is a valid MaterialX document in v%s" %
+              (opts.inputFilename, mx.getVersionString()))
+    else:
+        print("%s is not a valid MaterialX document in v%s" %
+              (opts.inputFilename, mx.getVersionString()))
+        print(message)
+
+    nodedefs = doc.getNodeDefs()
+    nodedef = findNodeDef(nodedefs, opts.nodedef)
+
+    print("Document Version: {}.{:02d}".format(*doc.getVersionIntegers()))
+    if nodedef is None:
+        print("Nodedef %s not found" % (opts.nodedef))
+    else:
+        try:
+            exportNodeDef(nodedef)
+            print("%d NodeDef%s found.\nNode '%s' exported to %s(.json/.hpp)"
+                % (len(nodedefs), pl(nodedefs), opts.nodedef, nodedef.getNodeString()))
+        except Exception as e:
+            print(e)
+            sys.exit(0)
+
+def findNodeDef(elemlist, nodedefname):
+    if len(elemlist) == 0:
+        return None
+    for elem in elemlist:
+        if elem.isA(mx.NodeDef) and elem.getName() == nodedefname:
+            return elem
+    return None
+
+def exportNodeDef(elem):
+    if elem.isA(mx.NodeDef):
+        jsonfilename = elem.getNodeString()+'.json'
+        hppfilename = elem.getNodeString()+'.hpp'
+        export_json(elem, jsonfilename)
+        export_hpp(elem, hppfilename)
+
+def export_json(elem, filename):
+    nodefInterface = {}
+    nodefInterface["Nodedef"] = elem.getName()
+    nodefInterface["SHA1"] = INPUTFILEHASH
+    nodefInterface["MaterialX"] = mx.getVersionString()
+    nodefInterface["name"] = elem.getNodeString()
+    asJsonArray(nodefInterface, elem)
+    with open(filename, 'w', encoding='utf-8') as f:
+        json.dump(nodefInterface, f, indent=4)
+
+def asJsonArray(nodefInterface, nodedef):
+    inputs = []
+    outputs = []
+    for inp in nodedef.getActiveInputs():
+        inputs.append((_getType(inp.getType()),
+                           inp.getName(),
+                           str(inp.getValue())))
+    nodefInterface["inputs"] = inputs
+    for output in nodedef.getActiveOutputs():
+        outputs.append((_getType(output.getType()),
+                           output.getName(),
+                           str(output.getValue())))
+    nodefInterface["outputs"] = outputs
+
+def export_hpp(elem, filename):
+    #      write to file
+    preamble = "/*\nGenerated using MaterialX nodedef \
+                  \n{nodename}\nSHA1:{filehash}\nVersion:{version}\n*/\n"\
+                  .format(nodename=elem, filehash=INPUTFILEHASH, version=mx.getVersionString())
+    variable_defs = ""
+    for inp in elem.getActiveInputs():
+        #create decl
+        decl = getVarDeclaration(inp)
+        #emit variable decl
+        if decl is None:
+            variable_def = '    {typename} {name};\n' \
+                .format(typename=_getType(inp.getType()),
+                        name=inp.getName())
+        else:
+            variable_def = '    {typename} {name} = {declaration};\n' \
+                .format(typename=_getType(inp.getType()),
+                        name=inp.getName(),
+                        declaration=decl)
+        variable_defs += variable_def
+    for output in elem.getActiveOutputs():
+        #create decl
+        decl = getVarDeclaration(output)
+        #emit output
+        if decl is None:
+            variable_def = '    {typename}* {name};\n' \
+                .format(typename=_getType(output.getType()),
+                        name=output.getName())
+        else:
+            variable_def = '    {typename} {name} = {declaration};\n' \
+                .format(typename=_getType(output.getType()),
+                        name=output.getName(),
+                        declaration=decl)
+        variable_defs += variable_def
+    nodename_definition = '    std::string _nodename_ = "{nodename}";\n'.format(
+        nodename=elem.getNodeString())
+    # create struct definition
+    struct_definition = """struct {structname} {{\n{variabledefs}{nodeiddef}}};""" \
+        .format(structname=elem.getName(),
+                variabledefs=variable_defs,
+                nodeiddef=nodename_definition)
+
+    with open(filename, 'w', encoding='utf-8') as f:
+        f.write(preamble)
+        f.write(struct_definition)
+        f.close()
+
+
+def getVarDeclaration(inputVar):
+
+    inputValue = inputVar.getValue()
+    typeName = _getType(inputVar.getType())
+    if isinstance(inputValue, (mx.Color3, mx.Vector3)):
+        val = '{typename}({v0}f, {v1}f, {v2}f)'.format(typename=typeName,
+                                                       v0=round(
+                                                           inputValue[0], 5),
+                                                       v1=round(
+                                                           inputValue[1], 5),
+                                                       v2=round(inputValue[2], 5))
+        return val
+    if isinstance(inputValue, (mx.Color4, mx.Vector4)):
+        val = '{typename}({v0}f, {v1}f, {v2}f, {v3}f)'.format(typename=typeName,
+                                                              v0=round(
+                                                                  inputValue[0], 5),
+                                                              v1=round(
+                                                                  inputValue[1], 5),
+                                                              v2=round(
+                                                                  inputValue[2], 5),
+                                                              v3=round(inputValue[3], 5))
+        return val
+    if isinstance(inputValue, float):
+        val = '{0}f'.format(round(inputValue, 5))
+        return val
+    if isinstance(inputValue, bool):
+        val = '{0}'.format('true' if inputValue is True else 'false')
+        return val
+    if isinstance(inputValue, int):
+        val = '{0}'.format(inputValue)
+        return val
+
+    # use input type if value is not defined and set default
+    defaultValue = _getDefault(inputVar.getType())
+    if inputValue is None:
+        if inputVar.getType() in ['vector2']:
+            val = '{typename}({v0}f, {v1}f)'.format(typename=typeName,
+                                                    v0=defaultValue[0],
+                                                    v1=defaultValue[1])
+            return val
+        if inputVar.getType() in ['vector3', 'color3']:
+            val = '{typename}({v0}f, {v1}f, {v2}f)'.format(typename=typeName,
+                                                           v0=defaultValue[0],
+                                                           v1=defaultValue[1],
+                                                           v2=defaultValue[2])
+            return val
+        if inputVar.getType() in ['vector4', 'color4']:
+            val = '{typename}({v0}f, {v1}f, {v2}f, {v3}f)'.format(typename=typeName,
+                                                                  v0=defaultValue[0],
+                                                                  v1=defaultValue[1],
+                                                                  v2=defaultValue[2],
+                                                                  v3=defaultValue[3])
+            return val
+        else:
+            print("unhandled: " + typeName)
+            return None
+
+
+def pl(elem):
+    if len(elem) == 1:
+        return ""
+    else:
+        return "s"
+
+
+if __name__ == '__main__':
+    main()

source/MaterialXCore/Value.cpp

@@ -31,6 +31,7 @@ template <class T> using enable_if_std_vector_t =
 template <class T> void stringToData(const string& str, T& data)
 {
     std::stringstream ss(str);
+    ss.imbue(std::locale::classic());
     if (!(ss >> data))
     {
         throw ExceptionTypeError("Type mismatch in generic stringToData: " + str);
@@ -94,7 +95,7 @@ template <class T> void stringToData(const string& str, enable_if_std_vector_t<T
 template <class T> void dataToString(const T& data, string& str)
 {
     std::stringstream ss;
-
+    ss.imbue(std::locale::classic());
     // Set float format and precision for the stream
     const Value::FloatFormat fmt = Value::getFloatFormat();
     ss.setf(std::ios_base::fmtflags(