ENH: add alternative STL ASCII parsers

- In addition to the traditional Flex-based parser, added a Ragel-based
  parser and a handwritten one.

  Some representative timings for reading 5874387 points (1958129 tris):

      Flex   Ragel   Manual
      5.2s   4.8s    6.7s         total reading time
      3.8s   3.4s    5.3s         without point merging

applications/test/string/Test-string.C

@@ -191,7 +191,12 @@ int main(int argc, char *argv[])
     Info<<"camel-case => " << (word("camel") & "case") << nl;
     for (const auto& s : { " text with \"spaces'", "08/15 value" })
     {
-        Info<<"validated \"" << s << "\" => "
+        // Character sequence
+
+        Info<<"validated 5 chars from \" => "
+            << word::validate(s, s+5, true) << nl;
+
+        Info<<"validated (via string convert) \"" << s << "\" => "
             << word::validate(s, true) << nl;
     }
     Info<< nl;

applications/test/surfaceReading/Make/files

@@ -0,0 +1,3 @@
+Test-surfaceReading.C
+
+EXE = $(FOAM_APPBIN)/Test-surfaceReading

applications/test/surfaceReading/Make/options

@@ -0,0 +1,6 @@
+EXE_INC = \
+    -I$(LIB_SRC)/fileFormats/lnInclude \
+    -I$(LIB_SRC)/surfMesh/lnInclude
+
+EXE_LIBS = \
+    -lsurfMesh

applications/test/surfaceReading/Test-surfaceReading.C

@@ -0,0 +1,145 @@
+/*---------------------------------------------------------------------------*\
+  =========                 |
+  \\      /  F ield         | OpenFOAM: The Open Source CFD Toolbox
+   \\    /   O peration     |
+    \\  /    A nd           | Copyright (C) 2018 OpenCFD Ltd.
+     \\/     M anipulation  |
+-------------------------------------------------------------------------------
+License
+    This file is part of OpenFOAM.
+
+    OpenFOAM is free software: you can redistribute it and/or modify it
+    under the terms of the GNU General Public License as published by
+    the Free Software Foundation, either version 3 of the License, or
+    (at your option) any later version.
+
+    OpenFOAM is distributed in the hope that it will be useful, but WITHOUT
+    ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+    FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
+    for more details.
+
+    You should have received a copy of the GNU General Public License
+    along with OpenFOAM.  If not, see <http://www.gnu.org/licenses/>.
+
+Application
+    Test-surfaceReading
+
+Description
+    Test basic surface format reading capabilities (and speeds)
+
+Note
+    The filename extensions are used to determine the file format type.
+
+\*---------------------------------------------------------------------------*/
+
+#include "argList.H"
+#include "Time.H"
+#include "clockTime.H"
+#include "triSurface.H"
+#include "MeshedSurfaces.H"
+#include "UnsortedMeshedSurfaces.H"
+#include "STLReader.H"
+
+using namespace Foam;
+
+// * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //
+
+int main(int argc, char *argv[])
+{
+    argList::addNote
+    (
+        "Test basic surface format reading capabilities (and speeds)"
+    );
+
+    argList::noParallel();
+    argList::addArgument("inputFile");
+
+    argList::addBoolOption
+    (
+        "triSurface",
+        "Use triSurface for read"
+    );
+    argList::addBoolOption
+    (
+        "triFace",
+        "Use triFace instead of face"
+    );
+    argList::addBoolOption
+    (
+        "unsorted",
+        "Use UnsortedMeshedSurface instead of MeshedSurface, "
+        "or unsorted output (with -triSurface option)"
+    );
+
+    argList::addOption
+    (
+        "ext",
+        "name",
+        "Force alternative extension"
+    );
+
+    argList::addOption
+    (
+        "stl-parser",
+        "N",
+        "ASCII parser type: 0=Flex, 1=Ragel, 2=Manual"
+    );
+
+    #include "setRootCase.H"
+
+    const fileName importName = args[1];
+
+    word ext;
+    if (!args.readIfPresent("ext", ext))
+    {
+        ext = importName.ext();
+        if (ext == "gz")
+        {
+            ext = importName.lessExt().ext();
+        }
+    }
+
+    args.readIfPresent("stl-parser", fileFormats::STLReader::parserType);
+
+    clockTime timing;
+
+    if (args.found("triSurface"))
+    {
+        triSurface surf(importName, ext);
+
+        Info<< "Read surface:" << endl;
+        surf.writeStats(Info);
+        Info<< "Area        : " << sum(surf.magSf()) << nl << endl;
+    }
+    else if (args.found("triFace"))
+    {
+        MeshedSurface<triFace> surf(importName, ext);
+
+        Info<< "Read surface:" << endl;
+        surf.writeStats(Info);
+        Info<< "Area        : " << sum(surf.magSf()) << nl << endl;
+    }
+    else if (args.found("unsorted"))
+    {
+        UnsortedMeshedSurface<face> surf(importName, ext);
+
+        Info<< "Read surface:" << endl;
+        surf.writeStats(Info);
+        Info<< "Area        : " << sum(surf.magSf()) << nl << endl;
+    }
+    else
+    {
+        MeshedSurface<face> surf(importName, ext);
+
+        Info<< "Read surface:" << endl;
+        surf.writeStats(Info);
+        Info<< "Area        : " << sum(surf.magSf()) << nl << endl;
+    }
+
+    Info<< nl << "Reading took " << timing.elapsedTime() << "s" << nl
+        << "\nEnd\n" << endl;
+
+    return 0;
+}
+
+// ************************************************************************* //

etc/controlDict

@@ -121,8 +121,12 @@ OptimisationSwitches
 
     // Force dumping (at next timestep) upon signal (-1 to disable) and exit
     stopAtWriteNowSignal    -1;
+
+    //- Choose STL ASCII parser:  0=Flex, 1=Ragel, 2=Manual
+    fileFormats::stl 0;
 }
 
+
 /* Can specify fallback profiling settings
 profiling
 {

src/OpenFOAM/primitives/strings/fileName/fileName.C

@@ -50,7 +50,7 @@ Foam::fileName Foam::fileName::validate
     out.resize(s.size());
 
     char prev = 0;
-    std::string::size_type count = 0;
+    std::string::size_type len = 0;
 
     // Largely as per stripInvalid
     for (auto iter = s.cbegin(); iter != s.cend(); ++iter)
@@ -66,17 +66,17 @@ Foam::fileName Foam::fileName::validate
             }
 
             // Only track valid chars
-            out[count++] = prev = c;
+            out[len++] = prev = c;
         }
     }
 
-    if (doClean && prev == '/' && count > 1)
+    if (doClean && prev == '/' && len > 1)
     {
         // Avoid trailing '/'
-        --count;
+        --len;
     }
 
-    out.resize(count);
+    out.resize(len);
 
     return out;
 }

src/OpenFOAM/primitives/strings/string/stringI.H

@@ -222,17 +222,18 @@ inline String Foam::string::validate(const std::string& str)
     String out;
     out.resize(str.size());
 
-    size_type count = 0;
+    size_type len = 0;
     for (auto iter = str.cbegin(); iter != str.cend(); ++iter)
     {
         const char c = *iter;
         if (String::valid(c))
         {
-            out[count++] = c;
+            out[len] = c;
+            ++len;
         }
     }
 
-    out.resize(count);
+    out.resize(len);
 
     return out;
 }

src/OpenFOAM/primitives/strings/word/word.C

@@ -41,7 +41,7 @@ Foam::word Foam::word::validate(const std::string& s, const bool prefix)
     word out;
     out.resize(s.size() + (prefix ? 1 : 0));
 
-    std::string::size_type count = 0;
+    std::string::size_type len = 0;
 
     // As per validate, but optionally detect if the first character
     // is a digit, which we'd like to avoid having since this will
@@ -52,17 +52,51 @@ Foam::word Foam::word::validate(const std::string& s, const bool prefix)
 
         if (word::valid(c))
         {
-            if (!count && prefix && isdigit(c))
+            if (!len && prefix && isdigit(c))
             {
                 // First valid character was a digit - prefix with '_'
-                out[count++] = '_';
+                out[len++] = '_';
             }
 
-            out[count++] = c;
+            out[len++] = c;
         }
     }
 
-    out.resize(count);
+    out.resize(len);
+
+    return out;
+}
+
+
+Foam::word Foam::word::validate
+(
+    const char* first,
+    const char* last,
+    const bool prefix
+)
+{
+    std::string::size_type len = (last - first) + (prefix ? 1 : 0);
+
+    word out;
+    out.resize(len);
+
+    for (len=0; first != last; ++first)
+    {
+        const char c = *first;
+
+        if (word::valid(c))
+        {
+            if (!len && prefix && isdigit(c))
+            {
+                // First valid character was a digit - prefix with '_'
+                out[len++] = '_';
+            }
+
+            out[len++] = c;
+        }
+    }
+
+    out.resize(len);
 
     return out;
 }

src/OpenFOAM/primitives/strings/word/word.H

@@ -148,6 +148,16 @@ public:
         //  that work nicely as dictionary keywords.
         static word validate(const std::string& s, const bool prefix=false);
 
+        //- Construct validated word (no invalid characters) from a sequence
+        //- of characters in the range [first,last),
+        //  Optionally prefix any leading digit with '_'.
+        static word validate
+        (
+            const char* first,
+            const char* last,
+            const bool prefix=false
+        );
+
 
     // File-like Functions
 

src/fileFormats/Make/files

@@ -12,7 +12,9 @@ fire/FIRECore.C
 starcd/STARCDCore.C
 stl/STLCore.C
 stl/STLReader.C
-stl/STLReaderASCII.L
+stl/STLAsciiParseFlex.L
+stl/STLAsciiParseManual.C
+stl/STLAsciiParseRagel.C
 
 vtk/core/foamVtkCore.C
 vtk/core/foamVtkPTraits.C

src/fileFormats/stl/STLAsciiParse.H

@@ -0,0 +1,153 @@
+/*--------------------------------*- C++ -*----------------------------------*\
+  =========                 |
+  \\      /  F ield         | OpenFOAM: The Open Source CFD Toolbox
+   \\    /   O peration     |
+    \\  /    A nd           | Copyright (C) 2018 OpenCFD Ltd.
+     \\/     M anipulation  |
+-------------------------------------------------------------------------------
+License
+    This file is part of OpenFOAM.
+
+    OpenFOAM is free software: you can redistribute it and/or modify it
+    under the terms of the GNU General Public License as published by
+    the Free Software Foundation, either version 3 of the License, or
+    (at your option) any later version.
+
+    OpenFOAM is distributed in the hope that it will be useful, but WITHOUT
+    ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+    FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
+    for more details.
+
+    You should have received a copy of the GNU General Public License
+    along with OpenFOAM.  If not, see <http://www.gnu.org/licenses/>.
+
+Class
+    Foam::Detail::STLAsciiParse
+
+Description
+    Internal class used when parsing STL ASCII format
+
+SourceFiles
+    STLAsciiParse.C
+
+\*---------------------------------------------------------------------------*/
+
+#ifndef STLAsciiParse_H
+#define STLAsciiParse_H
+
+#include "DynamicList.H"
+#include "HashTable.H"
+#include "STLpoint.H"
+
+// * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //
+
+namespace Foam
+{
+namespace Detail
+{
+
+/*---------------------------------------------------------------------------*\
+                    Class Detail::STLAsciiParse Declaration
+\*---------------------------------------------------------------------------*/
+
+class STLAsciiParse
+{
+protected:
+
+    // Protected Data
+
+        bool  sorted_;
+        label groupId_;      // The current solid group
+        label lineNum_;
+
+        //- The number of local points on the current facet
+        int nFacetPoints_;
+
+        //- Current vertex component when reading 'vertex'
+        int nVertexCmpt_;
+
+        //- Scratch space for reading 'vertex'
+        STLpoint currVertex_;
+
+        DynamicList<STLpoint> points_;
+        DynamicList<label> facets_;
+        DynamicList<word>  names_;
+        DynamicList<label> sizes_;
+        HashTable<label>   nameLookup_;
+
+
+    // Protected Member Functions
+
+        //- Action when entering 'solid'
+        inline void beginSolid(word solidName);
+
+        //- Action when entering 'facet'
+        inline void beginFacet();
+
+        //- Reset vertex component to zero
+        inline void resetVertex();
+
+        //- Add next vertex component. On each third call, adds the point.
+        //  \return true when point has been added (on the last component)
+        inline bool addVertexComponent(float val);
+
+        //- Add next vertex component. On each third call, adds the point.
+        //  \return true when point has been added (on the last component)
+        inline bool addVertexComponent(const char* text);
+
+        //- Action on 'endfacet'
+        inline void endFacet();
+
+
+        //- No copy construct
+        STLAsciiParse(const STLAsciiParse&) = delete;
+
+        //- No copy assignment
+        void operator=(const STLAsciiParse&) = delete;
+
+
+public:
+
+    // Constructors
+
+        //- From input stream and the approximate number of vertices in the STL
+        inline STLAsciiParse(const label approxNpoints);
+
+
+    // Member Functions
+
+        //- Reset stored values
+        inline void clear();
+
+        //- Do all the solid groups appear in order?
+        inline bool sorted() const;
+
+        //- A list of unstitched triangle points
+        inline DynamicList<STLpoint>& points();
+
+        //- A list of facet IDs (group IDs)
+        //- corresponds to the number of triangles
+        inline DynamicList<label>& facets();
+
+        //- Solid names in the order of their appearance.
+        inline DynamicList<word>& names();
+
+        //- Solid sizes in the order of their appearance.
+        inline DynamicList<label>& sizes();
+};
+
+
+// * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //
+
+} // End namespace Detail
+} // End namespace Foam
+
+// * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //
+
+#include "STLAsciiParseI.H"
+
+// * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //
+
+#endif
+
+// ************************************************************************* //

src/fileFormats/stl/STLAsciiParseFlex.L

@@ -3,7 +3,7 @@
   \\      /  F ield         | OpenFOAM: The Open Source CFD Toolbox
    \\    /   O peration     |
     \\  /    A nd           | Copyright (C) 2011-2016 OpenFOAM Foundation
-     \\/     M anipulation  | Copyright (C) 2016-2017 OpenCFD Ltd.
+     \\/     M anipulation  | Copyright (C) 2016-2018 OpenCFD Ltd.
 -------------------------------------------------------------------------------
 License
     This file is part of OpenFOAM.
@@ -21,18 +21,21 @@ License
     You should have received a copy of the GNU General Public License
     along with OpenFOAM.  If not, see <http://www.gnu.org/licenses/>.
 
+Description
+    Flex-based parsing of STL ASCII format
+
 \*---------------------------------------------------------------------------*/
 
 %option prefix="yySTL"
 %option yyclass="yySTLFlexLexer"
 
-
 %{
 
  /* ------------------------------------------------------------------------ *\
    ------ local definitions
  \* ------------------------------------------------------------------------ */
 
+#include "STLAsciiParse.H"
 #include "STLReader.H"
 #include "OSspecific.H"
 
@@ -40,6 +43,7 @@ License
 #pragma clang diagnostic ignored "-Wdeprecated-register"
 
 using namespace Foam;
+
 // Dummy yyFlexLexer::yylex() to keep the linker happy. It is not called
 //! \cond dummy
 #if YY_FLEX_MAJOR_VERSION <= 2 && YY_FLEX_MINOR_VERSION <= 5 && YY_FLEX_SUBMINOR_VERSION < 34
@@ -67,32 +71,27 @@ int yySTLFlexLexer::yywrap()
 }
 //! \endcond
 
+
 //- A lexer for parsing STL ASCII files.
 //  Returns DynamicList(s) of points and facets (zoneIds).
 //  The facets are within a solid/endsolid grouping
-class STLASCIILexer
+class STLAsciiParseFlex
 :
+    public Detail::STLAsciiParse,
     public yySTLFlexLexer
 {
-    // Private data
-
-        bool  sorted_;
-        label groupID_;      // current solid group
-        label lineNo_;
     word startError_;
 
-        DynamicList<STLpoint> points_;
-        DynamicList<label> facets_;
-        DynamicList<word>  names_;
-        DynamicList<label> sizes_;
-        HashTable<label>   lookup_;
-
 public:
 
     // Constructors
 
     //- From input stream and the approximate number of vertices in the STL
-        STLASCIILexer(istream* is, const label approxNpoints);
+    STLAsciiParseFlex(istream* is, const label approxNpoints)
+    :
+        Detail::STLAsciiParse(approxNpoints),
+        yySTLFlexLexer(is)
+    {}
 
 
     // Member Functions
@@ -100,78 +99,39 @@ public:
     //- The lexer function itself
     int lex();
 
-      // Access
+    //- Execute lexer
-
+    void execute()
-        //- Do all the solid groups appear in order?
-        inline bool sorted() const
     {
-            return sorted_;
+        while (lex()) {}
-        }
-
-        //- A list of unstitched triangle points
-        inline DynamicList<STLpoint>& points()
-        {
-            return points_;
-        }
-
-        //- A list of facet IDs (group IDs)
-        //  corresponds to the number of triangles
-        inline DynamicList<label>& facets()
-        {
-            return facets_;
-        }
-
-        //- Solid names in the order of their appearance.
-        inline DynamicList<word>& names()
-        {
-            return names_;
-        }
-
-        //- Solid sizes in the order of their appearance.
-        inline DynamicList<label>& sizes()
-        {
-            return sizes_;
     }
 };
 
 
-STLASCIILexer::STLASCIILexer(istream* is, const label approxNpoints)
-:
-    yySTLFlexLexer(is),
-    sorted_(true),
-    groupID_(-1),
-    lineNo_(1),
-    points_(approxNpoints),
-    facets_(approxNpoints)
-{}
-
-
  /* ------------------------------------------------------------------------ *\
    ------ cppLexer::yylex()
  \* ------------------------------------------------------------------------ */
 
 #undef YY_DECL
-#define YY_DECL int STLASCIILexer::lex()
+#define YY_DECL int STLAsciiParseFlex::lex()
 
 %}
 
-one_space             [ \t\f\r]
+white                 [ \t\f\r]
-space                 {one_space}*
+space                 {white}*
-some_space            {one_space}+
+some_space            {white}+
 
 alpha                 [_A-Za-z]
 digit                 [0-9]
 
-integer               {digit}+
+intNum                [-+]?{digit}+
-signedInteger         [-+]?{integer}
 
 word                  ([[:alnum:]]|[[:punct:]])*
 string                {word}({some_space}{word})*
 
-exponent_part         [eE][-+]?{digit}+
+expon                 [Ee][-+]?{digit}+
-fractional_constant   [-+]?(({digit}*"."{digit}+)|({digit}+"."?))
+fract                 [-+]?(({digit}*"."{digit}+)|({digit}+"."?))
 
-floatNum              (({fractional_constant}{exponent_part}?)|({digit}+{exponent_part}))
+floatNum              (({fract}{expon}?)|({digit}+{expon}))
 
 x                     {floatNum}
 y                     {floatNum}
@@ -205,13 +165,6 @@ endsolid              {space}("endsolid"|"ENDSOLID")({some_space}{word})*
 %%
 
 %{
-    // End of read character pointer returned by strtof
-    // char* endPtr;
-
-    label cmpt = 0;   // Component index when reading vertex
-    STLpoint vertex;
-    // STLpoint normal;
-
     static const char* stateNames[7] =
     {
         "reading solid",
@@ -247,62 +200,13 @@ endsolid              {space}("endsolid"|"ENDSOLID")({some_space}{word})*
 }
 
 <readSolidName>{string} {
-    const word solidName(word::validate(YYText()));
+    beginSolid(word::validate(YYText()));
-
-    auto iter = lookup_.cfind(solidName);
-    if (iter.found())
-    {
-        if (groupID_ != iter.object())
-        {
-            sorted_ = false;  // Group appeared out of order
-            groupID_ = iter.object();
-        }
-    }
-    else
-    {
-        groupID_ = sizes_.size();
-        if (lookup_.insert(solidName, groupID_))
-        {
-            names_.append(solidName);
-            sizes_.append(0);
-        }
-        else
-        {
-            FatalErrorInFunction<< "Duplicate solid-name: " << solidName
-                << exit(FatalError);
-        }
-    }
     BEGIN(INITIAL);
 }
 
 <readSolidName>{space}\n {
-    const word solidName("solid");  // Could also use solid0, solid1, ...
+    beginSolid("solid");  // Could also use solid0, solid1, ...
-
+    ++lineNum_;
-    auto iter = lookup_.cfind(solidName);
-    if (iter.found())
-    {
-        if (groupID_ != iter.object())
-        {
-            sorted_ = false;  // Group appeared out of order
-            groupID_ = iter.object();
-        }
-    }
-    else
-    {
-        groupID_ = sizes_.size();
-        if (lookup_.insert(solidName, groupID_))
-        {
-            names_.append(solidName);
-            sizes_.append(0);
-        }
-        else
-        {
-            FatalErrorInFunction<< "Duplicate solid-name: " << solidName
-                << exit(FatalError);
-        }
-    }
-
-    ++lineNo_;
     BEGIN(INITIAL);
 }
 
@@ -311,6 +215,7 @@ endsolid              {space}("endsolid"|"ENDSOLID")({some_space}{word})*
 }
 
 {facet} {
+    beginFacet();
     BEGIN(readFacet);
 }
 
@@ -337,24 +242,16 @@ endsolid              {space}("endsolid"|"ENDSOLID")({some_space}{word})*
     BEGIN(readVertex);
 }
 
-<readVertex>{space}{signedInteger}{space} {
+<readVertex>{space}{intNum}{space} {
-    vertex[cmpt++] = atol(YYText());
+    if (addVertexComponent(float(::atol(YYText()))))
-
-    if (cmpt == 3)
     {
-        cmpt = 0;
-        points_.append(vertex);
         BEGIN(readVertices);
     }
 }
 
 <readVertex>{space}{floatNum}{space} {
-    vertex[cmpt++] = atof(YYText());
+    if (addVertexComponent(::atof(YYText())))
-
-    if (cmpt == 3)
     {
-        cmpt = 0;
-        points_.append(vertex);
         BEGIN(readVertices);
     }
 }
@@ -364,8 +261,7 @@ endsolid              {space}("endsolid"|"ENDSOLID")({some_space}{word})*
 }
 
 <readFacet>{endfacet} {
-    facets_.append(groupID_);
+    endFacet();
-    sizes_[groupID_]++;
     BEGIN(INITIAL);
 }
 
@@ -376,7 +272,7 @@ endsolid              {space}("endsolid"|"ENDSOLID")({some_space}{word})*
  /* ---------------- Ignore remaining spaces and newlines ------------------ */
 
 <*>{space} {}
-<*>\n      { ++lineNo_; }
+<*>\n      { ++lineNum_; }
 
 
  /* ------------------- Any other characters are errors -------------------- */
@@ -392,7 +288,7 @@ endsolid              {space}("endsolid"|"ENDSOLID")({some_space}{word})*
 <stlError>.* {
     yy_pop_state();
     FatalErrorInFunction
-        << "while " << stateNames[YY_START] << " on line " << lineNo_ << nl
+        << "while " << stateNames[YY_START] << " on line " << lineNum_ << nl
         << "    expected " << stateExpects[YY_START]
         << " but found '" << startError_.c_str() << YYText() << "'"
         << exit(FatalError);
@@ -408,15 +304,13 @@ endsolid              {space}("endsolid"|"ENDSOLID")({some_space}{word})*
 
 
 //
-// member function
+// Member Function
 //
-bool Foam::fileFormats::STLReader::readASCII
+bool Foam::fileFormats::STLReader::readAsciiFlex
 (
     const fileName& filename
 )
 {
-    format_ = STLFormat::UNKNOWN;
-
     IFstream is(filename);
     if (!is)
     {
@@ -425,20 +319,12 @@ bool Foam::fileFormats::STLReader::readASCII
             << exit(FatalError);
     }
 
-    // Create the lexer with the approximate number of vertices in the STL
+    // Create with approx number of vertices in the STL (from file size)
-    // from the file size
+    STLAsciiParseFlex lexer(&(is.stdStream()), Foam::fileSize(filename)/400);
-    STLASCIILexer lexer(&(is.stdStream()), Foam::fileSize(filename)/400);
+    lexer.execute();
-    while (lexer.lex() != 0) {}
 
-    sorted_ = lexer.sorted();
+    transfer(lexer);
 
-    // Transfer to normal lists
-    points_.transfer(lexer.points());
-    zoneIds_.transfer(lexer.facets());
-    names_.transfer(lexer.names());
-    sizes_.transfer(lexer.sizes());
-
-    format_ = STLFormat::ASCII;
     return true;
 }
 

src/fileFormats/stl/STLAsciiParseI.H

@@ -0,0 +1,192 @@
+/*--------------------------------*- C++ -*----------------------------------*\
+  =========                 |
+  \\      /  F ield         | OpenFOAM: The Open Source CFD Toolbox
+   \\    /   O peration     |
+    \\  /    A nd           | Copyright (C) 2018 OpenCFD Ltd.
+     \\/     M anipulation  |
+-------------------------------------------------------------------------------
+License
+    This file is part of OpenFOAM.
+
+    OpenFOAM is free software: you can redistribute it and/or modify it
+    under the terms of the GNU General Public License as published by
+    the Free Software Foundation, either version 3 of the License, or
+    (at your option) any later version.
+
+    OpenFOAM is distributed in the hope that it will be useful, but WITHOUT
+    ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+    FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
+    for more details.
+
+    You should have received a copy of the GNU General Public License
+    along with OpenFOAM.  If not, see <http://www.gnu.org/licenses/>.
+
+\*---------------------------------------------------------------------------*/
+
+// * * * * * * * * * * * * Protected Member Functions  * * * * * * * * * * * //
+
+inline void Foam::Detail::STLAsciiParse::beginSolid(word solidName)
+{
+    if (solidName.empty())
+    {
+        solidName = "solid";  // Could also use solid0, solid1, ...
+    }
+
+    auto iter = nameLookup_.cfind(solidName);
+    if (iter.found())
+    {
+        if (groupId_ != iter.object())
+        {
+            sorted_ = false;  // Group appeared out of order
+            groupId_ = iter.object();
+        }
+    }
+    else
+    {
+        groupId_ = sizes_.size();
+        if (nameLookup_.insert(solidName, groupId_))
+        {
+            names_.append(solidName);
+            sizes_.append(0);
+        }
+        else
+        {
+            FatalErrorInFunction<< "Duplicate solid-name: " << solidName
+                << exit(FatalError);
+        }
+    }
+}
+
+
+inline void Foam::Detail::STLAsciiParse::beginFacet()
+{
+    nFacetPoints_ = 0;
+    nVertexCmpt_ = 0;
+}
+
+
+inline void Foam::Detail::STLAsciiParse::resetVertex()
+{
+    nVertexCmpt_ = 0;
+}
+
+
+inline bool Foam::Detail::STLAsciiParse::addVertexComponent(float val)
+{
+    currVertex_[nVertexCmpt_] = val;
+
+    if (++nVertexCmpt_ == 3)
+    {
+        points_.append(currVertex_);
+        nVertexCmpt_ = 0;
+        ++nFacetPoints_;
+    }
+
+    return !nVertexCmpt_;
+}
+
+
+inline bool Foam::Detail::STLAsciiParse::addVertexComponent(const char* text)
+{
+    //-> safer, but slower: readFloat(text, currVertex_[nVertexCmpt_]);
+    currVertex_[nVertexCmpt_] = ::atof(text);
+
+    if (++nVertexCmpt_ == 3)
+    {
+        points_.append(currVertex_);
+        nVertexCmpt_ = 0;
+        ++nFacetPoints_;
+    }
+
+    return !nVertexCmpt_;
+}
+
+
+inline void Foam::Detail::STLAsciiParse::endFacet()
+{
+    if (nFacetPoints_ == 3)
+    {
+        facets_.append(groupId_);
+        sizes_[groupId_]++;
+    }
+    else
+    {
+        if (nFacetPoints_ > 3)
+        {
+            nFacetPoints_ -= 3;
+        }
+
+        if (nFacetPoints_)
+        {
+            points_.resize(points_.size() - nFacetPoints_);
+        }
+    }
+
+    nFacetPoints_ = 0;
+}
+
+
+// * * * * * * * * * * * * * * * * Constructors  * * * * * * * * * * * * * * //
+
+inline Foam::Detail::STLAsciiParse::STLAsciiParse(const label approxNpoints)
+:
+    sorted_(true),
+    groupId_(-1),
+    lineNum_(1),
+    nFacetPoints_(0),
+    nVertexCmpt_(0),
+    points_(approxNpoints),
+    facets_(approxNpoints/2)
+{}
+
+
+// * * * * * * * * * * * * * * * Member Functions  * * * * * * * * * * * * * //
+
+inline void Foam::Detail::STLAsciiParse::clear()
+{
+    sorted_ = true;
+    groupId_ = -1;
+    lineNum_ = 0;
+
+    nFacetPoints_ = 0;
+    nVertexCmpt_ = 0;
+
+    points_.clear();
+    facets_.clear();
+    names_.clear();
+    sizes_.clear();
+    nameLookup_.clear();
+}
+
+
+inline bool Foam::Detail::STLAsciiParse::sorted() const
+{
+    return sorted_;
+}
+
+
+inline Foam::DynamicList<Foam::STLpoint>& Foam::Detail::STLAsciiParse::points()
+{
+    return points_;
+}
+
+
+inline Foam::DynamicList<Foam::label>& Foam::Detail::STLAsciiParse::facets()
+{
+    return facets_;
+}
+
+
+inline Foam::DynamicList<Foam::word>& Foam::Detail::STLAsciiParse::names()
+{
+    return names_;
+}
+
+
+inline Foam::DynamicList<Foam::label>& Foam::Detail::STLAsciiParse::sizes()
+{
+    return sizes_;
+}
+
+
+// ************************************************************************* //

src/fileFormats/stl/STLAsciiParseManual.C

@@ -0,0 +1,423 @@
+/*--------------------------------*- C++ -*----------------------------------*\
+  =========                 |
+  \\      /  F ield         | OpenFOAM: The Open Source CFD Toolbox
+   \\    /   O peration     |
+    \\  /    A nd           | Copyright (C) 2018 OpenCFD Ltd.
+     \\/     M anipulation  |
+-------------------------------------------------------------------------------
+License
+    This file is part of OpenFOAM.
+
+    OpenFOAM is free software: you can redistribute it and/or modify it
+    under the terms of the GNU General Public License as published by
+    the Free Software Foundation, either version 3 of the License, or
+    (at your option) any later version.
+
+    OpenFOAM is distributed in the hope that it will be useful, but WITHOUT
+    ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+    FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
+    for more details.
+
+    You should have received a copy of the GNU General Public License
+    along with OpenFOAM.  If not, see <http://www.gnu.org/licenses/>.
+
+Description
+    Hand-written parsing of STL ASCII format
+
+\*---------------------------------------------------------------------------*/
+
+#include "STLAsciiParse.H"
+#include "STLReader.H"
+#include "OSspecific.H"
+#include "stringOps.H"
+
+// * * * * * * * * * * * * * * * Local Functions * * * * * * * * * * * * * * //
+
+static inline std::string perrorEOF(std::string expected)
+{
+    return "Premature EOF while reading '" + expected + "'";
+}
+
+
+static inline std::string perrorParse(std::string expected, std::string found)
+{
+    return "Parse error. Expecting '" + expected + "' found '" + found + "'";
+}
+
+
+/* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */
+
+namespace Foam
+{
+namespace Detail
+{
+
+//- A lexer for parsing STL ASCII files.
+//  Returns DynamicList(s) of points and facets (zoneIds).
+//  The facets are within a solid/endsolid grouping
+class STLAsciiParseManual
+:
+    public Detail::STLAsciiParse
+{
+    enum scanState
+    {
+        scanSolid = 0,
+        scanFacet,
+        scanLoop,
+        scanVerts,
+        scanEndLoop,
+        scanEndFacet,
+        scanEndSolid
+    };
+
+    scanState state_;
+
+    std::string errMsg_;
+
+    //- Like std:csub_match
+    typedef std::pair<const char*, const char*> tokenType;
+
+    // Tokenized line
+    DynamicList<tokenType, 16> tokens_;
+
+    //- Tokenize
+    inline std::string::size_type tokenize(const char *p, const char *pe)
+    {
+        const char* start = p;
+        tokens_.clear();
+
+        // Find not space
+        while (p < pe && isspace(*p))
+        {
+            if (*p == '\n' && lineNum_)
+            {
+                ++lineNum_;
+            }
+            ++p;
+        }
+
+        while (p != pe)
+        {
+            const char* beg = p;
+
+            // Find space
+            while (p < pe && !isspace(*p))
+            {
+                ++p;
+            }
+            tokens_.append(tokenType(beg, p));
+
+            // Find next
+            while (p < pe && isspace(*p))
+            {
+                if (*p == '\n')
+                {
+                    ++lineNum_;
+                    return (p - start);
+                }
+                ++p;
+            }
+        }
+
+        return (p - start);
+    }
+
+
+public:
+
+    //- From input stream and the approximate number of vertices in the STL
+    STLAsciiParseManual(const label approxNpoints)
+    :
+        Detail::STLAsciiParse(approxNpoints)
+    {}
+
+    //- Execute parser
+    void execute(std::istream& is);
+};
+
+} // end of namespace Detail
+} // end of namespace Foam
+
+
+/* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */
+
+// Length of the input read buffer
+#define INBUFLEN 16384
+
+void Foam::Detail::STLAsciiParseManual::execute(std::istream& is)
+{
+    if (!is)
+    {
+        return;
+    }
+
+    // Buffering
+    char inbuf[INBUFLEN];
+    std::streamsize pending = 0;
+
+    lineNum_ = 0;
+
+    state_ = scanSolid;
+    errMsg_.clear();
+
+    // Line-oriented processing loop
+    while (is)
+    {
+        if (pending >= INBUFLEN)
+        {
+            // We overfilled the buffer while trying to scan a token...
+            FatalErrorInFunction
+                << "buffer full while scanning near line " << lineNum_ << nl;
+            break;
+        }
+
+        char *data = inbuf + pending;   // current data buffer
+        const std::streamsize buflen = INBUFLEN - pending; // space in buffer
+
+        is.read(data, buflen);
+        const std::streamsize gcount = is.gcount();
+
+        if (!gcount)
+        {
+            // EOF
+            // If scanning for next "solid" this is a valid way to exit, but
+            // an error if scanning for the initial "solid" or any other token
+
+            switch (state_)
+            {
+                case scanSolid:
+                {
+                    if (!lineNum_) errMsg_ = perrorEOF("solid");
+                    break;
+                }
+                case scanFacet:    { errMsg_ = perrorEOF("facet"); break; }
+                case scanLoop:     { errMsg_ = perrorEOF("outer loop"); break; }
+                case scanVerts:    { errMsg_ = perrorEOF("vertex"); break; }
+                case scanEndLoop:  { errMsg_ = perrorEOF("endloop"); break; }
+                case scanEndFacet: { errMsg_ = perrorEOF("endfacet"); break; }
+                case scanEndSolid: { errMsg_ = perrorEOF("endsolid"); break; }
+            }
+
+            // Terminate the parsing loop
+            break;
+        }
+
+        // p,pe = Ragel parsing point and parsing end (default naming)
+        // eof  = Ragel EOF point (default naming)
+
+        char *p = inbuf;
+        char *pe = data + gcount;
+
+        // Line-oriented: search backwards to find last newline
+        {
+            --pe;
+            while (*pe != '\n' && pe >= inbuf)
+            {
+                --pe;
+            }
+            ++pe;
+        }
+
+        std::string cmd;
+        do
+        {
+            // Tokenize
+            const auto parsedLen = tokenize(p, pe);
+            p += parsedLen;
+            if (!parsedLen || tokens_.empty())
+            {
+                break;
+            }
+
+            // Ensure consistent case on the first token
+            cmd.assign(tokens_[0].first, tokens_[0].second);
+            stringOps::lower(cmd);
+
+            // Handle all expected parse states
+            switch (state_)
+            {
+                case scanSolid:
+                {
+                    if (cmd == "solid")
+                    {
+                        if (tokens_.empty())
+                        {
+                            beginSolid(word::null);
+                        }
+                        else
+                        {
+                            beginSolid
+                            (
+                                word::validate(tokens_[1].first, tokens_[1].second)
+                            );
+                        }
+
+                        state_ = scanFacet;  // Next state
+                    }
+                    else
+                    {
+                        errMsg_ = perrorParse("solid", cmd);
+                    }
+                    break;
+                }
+                case scanFacet:
+                {
+                    if (cmd == "color")
+                    {
+                        // Optional 'color' entry (after solid)
+                        // - continue looking for 'facet'
+                        continue;
+                    }
+                    else if (cmd == "facet")
+                    {
+                        beginFacet();
+                        state_ = scanLoop;  // Next state
+                    }
+                    else if (cmd == "endsolid")
+                    {
+                        // Finished with 'endsolid' - find next solid
+                        state_ = scanSolid;
+                    }
+                    else
+                    {
+                        errMsg_ = perrorParse("facet", cmd);
+                    }
+                    break;
+                }
+                case scanLoop:
+                {
+                    if (cmd == "outer")
+                    {
+                        // More pedantic would with (tokens_[1] == "loop") too
+                        state_ = scanVerts;  // Next state
+                    }
+                    else
+                    {
+                        errMsg_ = perrorParse("outer loop", cmd);
+                    }
+                    break;
+                }
+                case scanVerts:
+                {
+                    if (cmd == "vertex")
+                    {
+                        if (tokens_.size() > 3)
+                        {
+                            // Although tokens are not nul-terminated,
+                            // they are space delimited and thus good enough for atof()
+                            addVertexComponent(tokens_[1].first);
+                            addVertexComponent(tokens_[2].first);
+                            addVertexComponent(tokens_[3].first);
+                        }
+                        else
+                        {
+                            errMsg_ = "Error parsing vertex value";
+                        }
+                    }
+                    else if (cmd == "endloop")
+                    {
+                        state_ = scanEndFacet;  // Next state
+                    }
+                    else
+                    {
+                        errMsg_ = perrorParse("vertex", cmd);
+                    }
+                    break;
+                }
+                case scanEndLoop:
+                {
+                    if (cmd == "endloop")
+                    {
+                        state_ = scanEndFacet;  // Next state
+                    }
+                    else
+                    {
+                        errMsg_ = perrorParse("endloop", cmd);
+                    }
+                    break;
+                }
+                case scanEndFacet:
+                {
+                    if (cmd == "endfacet")
+                    {
+                        endFacet();
+                        state_ = scanFacet;  // Next facet, or endsolid
+                    }
+                    else
+                    {
+                        errMsg_ = perrorParse("endfacet", cmd);
+                    }
+                    break;
+                }
+                case scanEndSolid:
+                {
+                    if (cmd == "endsolid")
+                    {
+                        state_ = scanSolid;  // Start over again
+                    }
+                    else
+                    {
+                        errMsg_ = perrorParse("endsolid", cmd);
+                    }
+                    break;
+                }
+            }
+        }
+        while (errMsg_.empty());
+
+        // How much still in the bufffer?
+        pending = data + gcount - pe;
+
+        if (pending)
+        {
+            memmove(inbuf, pe, pending);
+        }
+
+        if (gcount < buflen)
+        {
+            break; // done
+        }
+
+        if (!errMsg_.empty())
+        {
+            break;
+        }
+    }
+
+    if (!errMsg_.empty())
+    {
+        FatalErrorInFunction
+            << errMsg_ << nl;
+    }
+}
+
+
+/* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */
+
+//
+// Member Function
+//
+bool Foam::fileFormats::STLReader::readAsciiManual
+(
+    const fileName& filename
+)
+{
+    IFstream is(filename);
+    if (!is)
+    {
+        FatalErrorInFunction
+            << "file " << filename << " not found"
+            << exit(FatalError);
+    }
+
+    // Create with the approximate number of vertices in the STL from file size
+    Detail::STLAsciiParseManual lexer(Foam::fileSize(filename)/400);
+    lexer.execute(is.stdStream());
+
+    transfer(lexer);
+
+    return true;
+}
+
+
+// ************************************************************************* //

src/fileFormats/stl/STLAsciiParseRagel.rl

@@ -0,0 +1,310 @@
+/*--------------------------------*- C++ -*----------------------------------*\
+  =========                 |
+  \\      /  F ield         | OpenFOAM: The Open Source CFD Toolbox
+   \\    /   O peration     |
+    \\  /    A nd           | Copyright (C) 2018 OpenCFD Ltd.
+     \\/     M anipulation  |
+-------------------------------------------------------------------------------
+License
+    This file is part of OpenFOAM.
+
+    OpenFOAM is free software: you can redistribute it and/or modify it
+    under the terms of the GNU General Public License as published by
+    the Free Software Foundation, either version 3 of the License, or
+    (at your option) any later version.
+
+    OpenFOAM is distributed in the hope that it will be useful, but WITHOUT
+    ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+    FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
+    for more details.
+
+    You should have received a copy of the GNU General Public License
+    along with OpenFOAM.  If not, see <http://www.gnu.org/licenses/>.
+
+Description
+    Ragel-based parsing of STL ASCII format.
+    The goto-based finite state machine (FSM) is generated with
+
+        ragel -G2 -o STLAsciiParseRagel.C STLAsciiParseRagel.rl
+
+\*---------------------------------------------------------------------------*/
+
+#include "STLAsciiParse.H"
+#include "STLReader.H"
+#include "OSspecific.H"
+
+// https://en.wikipedia.org/wiki/STL_%28file_format%29#ASCII_STL
+//
+// Format
+//
+// solid [name]
+//
+// * where name is an optional string.
+// * The file continues with any number of triangles,
+//   each represented as follows:
+//
+// [color ...]
+// facet normal ni nj nk
+//     outer loop
+//         vertex v1x v1y v1z
+//         vertex v2x v2y v2z
+//         vertex v3x v3y v3z
+//     endloop
+// endfacet
+//
+// * where each n or v is a floating-point number.
+// * The file concludes with
+//
+// endsolid [name]
+
+// We take some parsing shortcuts.
+// - Ignore 'color' lines
+// - Only look for initial 'facet '. Ignore 'normal ...'
+// - Ignore name for 'endsolid'
+//
+
+// Ragel machine definition
+// Ragel variables (p, pe, eof, cs, top, stack, ts, te, act) defined later...
+//
+// Can use 'variable p xxx;' etc to change these names
+
+// Define the machine actions
+%%{
+    machine stlAscii;
+
+    action  buffer  { tok = p; /* Local token start */ }
+    action  nl      { ++lineNum_; }
+
+    action  bsolid  { beginSolid(word::validate(tok, p)); }
+    action  bfacet  { beginFacet(); }
+    action  efacet  { endFacet(); }
+
+    action  bvertex { resetVertex(); }
+    action  vertexCmpt
+    {
+        const char saveC = *p;
+        *p = '\0';  // Make nul-terminated
+
+        addVertexComponent(tok);
+        *p = saveC; // Restore previous character
+    }
+
+}%%
+
+
+%%{
+    machine stlAscii;
+
+    white   = [ \t\f\r];                # Horizontal whitespace
+    nl      = (white* '\n' %nl);        # Newline
+    dnl     = ([^\n]* '\n' %nl);        # Discard up to and including newline
+
+    decimal = ((digit* '.' digit+) | (digit+ '.'?)) ;
+    number  = [\-+]? (digit+ | decimal) ([Ee][\-+]? digit+)? ;
+
+    bfacet  = space* ("facet"|"FACET") white %bfacet dnl;
+    efacet  = space* ("endfacet"|"ENDFACET") %efacet dnl;
+
+    solidName =
+        ('' >buffer %bsolid nl)
+      | ((white+ [^\n]*) >buffer %bsolid nl);
+
+    bsolid =
+        space* ("solid"|"SOLID") solidName ;
+
+    esolid = space* ("endsolid"|"ENDSOLID") dnl;
+
+    color   = space* ("color"|"COLOR") dnl;
+
+    bloop   = space* ("outer" white+ "loop")|("OUTER" white+ "LOOP") dnl;
+    eloop   = space* ("endloop"|"ENDLOOP") dnl;
+
+    vertex  = space* ("vertex"|"VERTEX")
+        ((white+ (number > buffer %vertexCmpt)){3} nl);
+
+    main := space*
+    (
+        bsolid
+        color?
+        ( bfacet bloop (vertex)* eloop efacet )*
+        esolid
+    )+ space*;
+
+}%%
+
+
+//
+// FSM globals
+//
+
+%% write data nofinal;
+
+
+/* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */
+
+namespace Foam
+{
+namespace Detail
+{
+
+//- A lexer for parsing STL ASCII files.
+//  Returns DynamicList(s) of points and facets (zoneIds).
+//  The facets are within a solid/endsolid grouping
+class STLAsciiParseRagel
+:
+    public Detail::STLAsciiParse
+{
+    // Private Data
+    word  startError_;
+
+
+public:
+
+    //- From input stream and the approximate number of vertices in the STL
+    STLAsciiParseRagel(const label approxNpoints)
+    :
+        Detail::STLAsciiParse(approxNpoints)
+    {}
+
+    //- Execute lexer
+    void execute(std::istream& is);
+};
+
+} // end of namespace Detail
+} // end of namespace Foam
+
+
+/* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */
+
+// Length of the input read buffer
+#define INBUFLEN 16384
+
+void Foam::Detail::STLAsciiParseRagel::execute(std::istream& is)
+{
+    if (!is)
+    {
+        return;
+    }
+
+    // cs = code state
+    int cs;
+
+    %%{write init;}%%   /* ^^^ FSM initialization here ^^^ */;
+
+    // Local token start
+    char *tok = nullptr;
+
+    // Buffering
+    char inbuf[INBUFLEN];
+    std::streamsize pending = 0;
+
+    // Line-oriented processing loop (as per Ragel pdf example)
+
+    while (is)
+    {
+        if (pending >= INBUFLEN)
+        {
+            // We overfilled the buffer while trying to scan a token...
+            FatalErrorInFunction
+                << "buffer full while scanning near line " << lineNum_ << nl;
+            break;
+        }
+
+        char *data = inbuf + pending;   // current data buffer
+        const std::streamsize buflen = INBUFLEN - pending; // space in buffer
+
+        is.read(data, buflen);
+        const std::streamsize gcount = is.gcount();
+        if (!gcount)
+        {
+            break;
+        }
+
+        // p,pe = Ragel parsing point, parsing end (default naming)
+        // eof  = Ragel EOF point (default naming)
+
+        char *p = inbuf;
+        const char *pe = data + gcount;
+        const char *eof = nullptr;
+        if (!is)
+        {
+            eof = pe;   // Tag 'pe' as being the EOF for the FSM as well
+        }
+
+        // Line-oriented: search backwards to find last newline
+        {
+            --pe;
+            while (*pe != '\n' && pe >= inbuf)
+            {
+                --pe;
+            }
+            ++pe;
+        }
+
+        %%{write exec;}%%       /* ^^^ FSM execution here ^^^ */;
+
+        if (%%{write error;}%% == cs)
+        {
+            // FSM failed before finding a token
+            FatalErrorInFunction
+                << "parse error while scanning near line " << lineNum_ << nl;
+
+            if (p)
+            {
+                std::string::size_type errLen = (pe - p);
+                if (errLen > 80)
+                {
+                    errLen = 80;
+                }
+
+                FatalErrorInFunction
+                    << "context: " << std::string(p, errLen) << nl;
+            }
+            break;
+        }
+
+        // How much still in the bufffer?
+        pending = data + gcount - pe;
+
+        if (pending)
+        {
+            memmove(inbuf, pe, pending);
+        }
+
+        if (gcount < buflen)
+        {
+            break; // done
+        }
+    }
+}
+
+
+/* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */
+
+//
+// Member Function
+//
+bool Foam::fileFormats::STLReader::readAsciiRagel
+(
+    const fileName& filename
+)
+{
+    IFstream is(filename);
+    if (!is)
+    {
+        FatalErrorInFunction
+            << "file " << filename << " not found"
+            << exit(FatalError);
+    }
+
+    // Create with approx number of vertices in the STL (from file size)
+    Detail::STLAsciiParseRagel lexer(Foam::fileSize(filename)/400);
+    lexer.execute(is.stdStream());
+
+    transfer(lexer);
+
+    return true;
+}
+
+
+// ************************************************************************* //

src/fileFormats/stl/STLReader.C

@@ -24,14 +24,60 @@ License
 \*---------------------------------------------------------------------------*/
 
 #include "STLReader.H"
+#include "STLAsciiParse.H"
 #include "Map.H"
 #include "IFstream.H"
 #include "mergePoints.H"
 
 #undef DEBUG_STLBINARY
 
+/* * * * * * * * * * * * * * * Static Member Data  * * * * * * * * * * * * * */
+
+int Foam::fileFormats::STLReader::parserType
+(
+    Foam::debug::optimisationSwitch("fileFormats::stl", 0)
+);
+
+
 // * * * * * * * * * * * * * Private Member Functions  * * * * * * * * * * * //
 
+void Foam::fileFormats::STLReader::transfer
+(
+    Detail::STLAsciiParse& parsed
+)
+{
+    sorted_ = parsed.sorted();
+
+    points_.transfer(parsed.points());
+    zoneIds_.transfer(parsed.facets());
+    names_.transfer(parsed.names());
+    sizes_.transfer(parsed.sizes());
+
+    format_ = STLFormat::ASCII;
+
+    parsed.clear();
+}
+
+
+bool Foam::fileFormats::STLReader::readASCII
+(
+    const fileName& filename
+)
+{
+    // No runtime selection of parser (only via optimisationSwitch)
+    // this is something that is infrequently changed.
+    if (parserType == 1)
+    {
+        return readAsciiRagel(filename);
+    }
+    else if (parserType == 2)
+    {
+        return readAsciiManual(filename);
+    }
+    return readAsciiFlex(filename);
+}
+
+
 bool Foam::fileFormats::STLReader::readBINARY
 (
     const fileName& filename
@@ -189,12 +235,6 @@ Foam::fileFormats::STLReader::STLReader
 }
 
 
-// * * * * * * * * * * * * * * * * Destructor  * * * * * * * * * * * * * * * //
-
-Foam::fileFormats::STLReader::~STLReader()
-{}
-
-
 // * * * * * * * * * * * * * * Member Functions  * * * * * * * * * * * * * * //
 
 void Foam::fileFormats::STLReader::clear()

src/fileFormats/stl/STLReader.H

@@ -45,6 +45,15 @@ SourceFiles
 
 namespace Foam
 {
+
+namespace Detail
+{
+
+// Forward Declarations
+class STLAsciiParse;
+
+}
+
 namespace fileFormats
 {
 
@@ -78,7 +87,19 @@ class STLReader
 
     // Private Member Functions
 
-        //- Read ASCII
+        //- Transfer parsed information to normal lists
+        void transfer(Detail::STLAsciiParse& parsed);
+
+        //- Parse/read ASCII using Flex-based parser
+        bool readAsciiFlex(const fileName& filename);
+
+        //- Parse/read ASCII using Ragel-based parser
+        bool readAsciiRagel(const fileName& filename);
+
+        //- Parse/read ASCII using simple handwritten parser
+        bool readAsciiManual(const fileName& filename);
+
+        //- Parse/read ASCII
         bool readASCII(const fileName& filename);
 
         //- Read BINARY
@@ -88,15 +109,21 @@ class STLReader
         bool readFile(const fileName& filename, const STLFormat format);
 
 
-        //- Disallow default bitwise copy construct
+        //- No copy construct
         STLReader(const STLReader&) = delete;
 
-        //- Disallow default bitwise assignment
+        //- No copy assignment
         void operator=(const STLReader&) = delete;
 
 
 public:
 
+    // Static Data
+
+        //- ASCII parser types (0=Flex, 1=Ragel, 2=Manual)
+        static int parserType;
+
+
     // Constructors
 
         //- Read from file, filling in the information.
@@ -109,7 +136,7 @@ public:
 
 
     //- Destructor
-    ~STLReader();
+    ~STLReader() = default;
 
 
     // Member Functions

src/surfMesh/surfaceFormats/stl/STLsurfaceFormat.H

@@ -82,10 +82,10 @@ class STLsurfaceFormat
         );
 
 
-        //- Disallow default bitwise copy construct
+        //- No copy construct
         STLsurfaceFormat(const STLsurfaceFormat<Face>&) = delete;
 
-        //- Disallow default bitwise assignment
+        //- No copy assignment
         void operator=(const STLsurfaceFormat<Face>&) = delete;
 
 

src/surfMesh/triSurface/triSurface.C

@@ -491,19 +491,30 @@ Foam::triSurface::triSurface
 }
 
 
-Foam::triSurface::triSurface(const fileName& name, const scalar scaleFactor)
+Foam::triSurface::triSurface
+(
+    const fileName& name,
+    const scalar scaleFactor
+)
+:
+    triSurface(name, name.ext(), scaleFactor)
+{}
+
+
+Foam::triSurface::triSurface
+(
+    const fileName& name,
+    const word& ext,
+    const scalar scaleFactor
+)
 :
     ParentType(List<Face>(), pointField()),
     patches_(),
     sortedEdgeFacesPtr_(nullptr),
     edgeOwnerPtr_(nullptr)
 {
-    const word ext = name.ext();
-
     read(name, ext);
-
     scalePoints(scaleFactor);
-
     setDefaultPatches();
 }
 

src/surfMesh/triSurface/triSurface.H

@@ -285,6 +285,14 @@ public:
         //  Optional (positive, non-zero) point scaling is possible.
         triSurface(const fileName& name, const scalar scaleFactor = -1);
 
+        //- Construct from file name (uses extension to determine type)
+        triSurface
+        (
+            const fileName& name,
+            const word& ext,
+            const scalar scaleFactor = -1
+        );
+
         //- Construct from Istream
         triSurface(Istream& is);