0000572: add a method to Part module to read BRep data from string

git-svn-id: https://free-cad.svn.sourceforge.net/svnroot/free-cad/trunk@5410 e8eeb9e2-ec13-0410-a4a9-efa5cf37419d

src/Base/Stream.cpp

@@ -40,6 +40,7 @@
 #include "Stream.h"
 #include "Swap.h"
 #include "FileInfo.h"
+#include <CXX/Objects.hxx>
 
 using namespace Base;
 
@@ -535,6 +536,58 @@ IODeviceIStreambuf::seekpos(std::streambuf::pos_type pos,
 
 // ---------------------------------------------------------
 
+PyStreambuf::PyStreambuf(PyObject* o) : inp(o)
+{
+    setg (buffer+pbSize,
+          buffer+pbSize,
+          buffer+pbSize);
+}
+
+int PyStreambuf::underflow()
+{
+    if (gptr() < egptr()) {
+        return *gptr();
+    }
+
+    int numPutback;
+    numPutback = gptr() - eback();
+    if (numPutback > pbSize) {
+        numPutback = pbSize;
+    }
+
+    memcpy (buffer+(pbSize-numPutback), gptr()-numPutback, numPutback);
+
+    int num=0;
+    for (int i=0; i<bufSize; i++) {
+        char c;
+        Py::Tuple arg(1);
+        arg.setItem(0, Py::Int(1));
+        Py::Callable meth(Py::Object(inp).getAttr("read"));
+        try {
+            Py::Char res(meth.apply(arg));
+            c = static_cast<std::string>(res)[0];
+            num++;
+            buffer[pbSize+i] = c;
+            if (c == '\n')
+                break;
+        }
+        catch (Py::Exception& e) {
+            e.clear();
+            if (num == 0)
+                return EOF;
+            break;
+        }
+    }
+
+    setg (buffer+(pbSize-numPutback),
+          buffer+pbSize,
+          buffer+pbSize+num);
+
+    return *gptr();
+}
+
+// ---------------------------------------------------------
+
 Streambuf::Streambuf(const std::string& data)
 {
     _beg = data.begin();

src/Base/Stream.h

@@ -35,6 +35,7 @@
 class QByteArray;
 class QIODevice;
 class QBuffer;
+typedef struct _object PyObject;
 
 namespace Base {
 
@@ -233,6 +234,21 @@ protected:
     char buffer[bufSize+pbSize];        // data buffer
 };
 
+class BaseExport PyStreambuf : public std::streambuf
+{
+public:
+    PyStreambuf(PyObject* o);
+
+protected:
+    int underflow();
+
+private:
+    static const int pbSize = 4;
+    static const int bufSize = 1024;
+    char buffer[bufSize+pbSize];
+    PyObject* inp;
+};
+
 class BaseExport Streambuf : public std::streambuf
 {
 public:

src/Mod/Part/App/TopoShape.cpp

@@ -609,6 +609,32 @@ void TopoShape::importBrep(const char *FileName)
     }
 }
 
+void TopoShape::importBrep(std::istream& str)
+{
+    try {
+        // read brep-file
+        BRep_Builder aBuilder;
+        TopoDS_Shape aShape;
+#if OCC_HEX_VERSION >= 0x060300
+        Handle_Message_ProgressIndicator pi = new ProgressIndicator(100);
+        pi->NewScope(100, "Reading BREP file...");
+        pi->Show();
+        BRepTools::Read(aShape,str,aBuilder,pi);
+        pi->EndScope();
+#else
+        BRepTools::Read(aShape,str,aBuilder);
+#endif
+        this->_Shape = aShape;
+    }
+    catch (Standard_Failure) {
+        Handle(Standard_Failure) aFail = Standard_Failure::Caught();
+        throw Base::Exception(aFail->GetMessageString());
+    }
+    catch (const std::exception& e) {
+        throw Base::Exception(e.what());
+    }
+}
+
 void TopoShape::write(const char *FileName) const
 {
     Base::FileInfo File(FileName);

src/Mod/Part/App/TopoShape.h

@@ -120,6 +120,7 @@ public:
     void importIges(const char *FileName);
     void importStep(const char *FileName);
     void importBrep(const char *FileName);
+    void importBrep(std::istream&);
     void exportIges(const char *FileName) const;
     void exportStep(const char *FileName) const;
     void exportBrep(const char *FileName) const;

src/Mod/Part/App/TopoShapePy.xml

@@ -48,6 +48,11 @@ Sub-elements such as vertices, edges or faces are accessible as:
         <UserDocu>Export the content of this shape to an STL mesh file.</UserDocu>
       </Documentation>
     </Methode>
+    <Methode Name="importBrep">
+      <Documentation>
+        <UserDocu>Import the content to this shape of a string in BREP format.</UserDocu>
+      </Documentation>
+    </Methode>
     <Methode Name="extrude">
       <Documentation>
         <UserDocu>Extrude the shape along a direction.</UserDocu>

src/Mod/Part/App/TopoShapePyImp.cpp

@@ -311,6 +311,30 @@ PyObject*  TopoShapePy::exportBrep(PyObject *args)
     Py_Return;
 }
 
+PyObject*  TopoShapePy::importBrep(PyObject *args)
+{
+    PyObject* input;
+    if (!PyArg_ParseTuple(args, "O", &input))
+    //char* input;
+    //if (!PyArg_ParseTuple(args, "s", &input))
+        return NULL;
+
+    try {
+        // read brep
+        Base::PyStreambuf buf(input);
+        std::istream str(0);
+        str.rdbuf(&buf);
+        //std::stringstream str(input);
+        getTopoShapePtr()->importBrep(str);
+    }
+    catch (const Base::Exception& e) {
+        PyErr_SetString(PyExc_Exception,e.what());
+        return NULL;
+    }
+
+    Py_Return;
+}
+
 PyObject*  TopoShapePy::exportStl(PyObject *args)
 {
     char* filename;