Hi

I'm trying to convert a vector of doubles to a QByteArray; see code extract below.

It appears to pack the vector of doubles ok but the toOK booleans in toFloat(&toOK) are all set to false when trying to unpack.

Has anyone else ever done this operation before?

Thanks for your help as this is driving me crazy.

Graham

Qt Code: 
  1. void testAddVertices(const QVector<VertexType>& vertices)
  2. {
  3. 	int numberVertices = vertices.size();
  4.  
  5. 	QByteArray	byteArray;
  6. 	QDataStream out(&byteArray,QIODevice::ReadWrite);
  7.  
  8. 	//double vx, vy, vz; // 64bit
  9. 	float  vx, vy, vz; // 32bit
  10. 	for (int i=0; i<numberVertices; i++)
  11. 	{
  12. 		const VertexType& v = vertices[i];
  13. 		vx = v.x(); vy = v.y(); vz = v.z();
  14. 		out << vx; out << vy; out << vz;
  15. 	}
  16.  
  17. 	byteArray = byteArray.toHex();
  18. 	const char* data = byteArray.constData();
  19. 	QString qdata(data);
  20. 	std::string qdatas = qdata.toStdString(); 
  21. 	std::cout << "qdata: " << qdatas << std::endl;
  22.  
  23. 	// extract
  24. 	QByteArray	byteArrayExtracted = QByteArray::fromHex(byteArray);
  25. 	QBuffer buffer(&byteArrayExtracted);
  26. 	//QBuffer buffer(&byteArray);
  27. 	buffer.open(QIODevice::ReadOnly);
  28. 	qint64 vertexComponentLength = 8;
  29. 	qint64 vertexLength = 3*vertexComponentLength;
  30. 	qint64 seekPos = 0;
  31. 	qint64 numberBytesRead;
  32. 	bool toOK, seekOK;
  33. 	char* vxChar = new char[vertexComponentLength];
  34. 	char* vyChar = new char[vertexComponentLength];
  35. 	char* vzChar = new char[vertexComponentLength];
  36. 	for (int i=0; i<numberVertices; i++)
  37. 	{
  38. 		numberBytesRead = buffer.read(vxChar,vertexComponentLength);
  39.  
  40. 		seekOK = buffer.seek(seekPos+vertexComponentLength);
  41. 		numberBytesRead = buffer.read(vyChar,vertexComponentLength);
  42.  
  43. 		seekOK = buffer.seek(seekPos+2*vertexComponentLength);
  44. 		numberBytesRead = buffer.read(vzChar,vertexComponentLength);
  45.  
  46. 		QByteArray vxCharArray(vxChar,vertexComponentLength);
  47. 		//vxCharArray = QByteArray::fromHex(vxCharArray);
  48. 		float vx = vxCharArray.toFloat(&toOK);
  49. 		QByteArray vyCharArray(vyChar,vertexComponentLength);
  50. 		//vyCharArray = QByteArray::fromHex(vyCharArray);
  51. 		float vy = vyCharArray.toFloat(&toOK);
  52. 		QByteArray vzCharArray(vzChar,vertexComponentLength);
  53. 		//vzCharArray = QByteArray::fromHex(vzCharArray);
  54. 		float vz = vzCharArray.toFloat(&toOK);
  55.  
  56. 		VertexType v(vx,vy,vz);
  57. 		std::cout << "v(" << vx << ", " << vy << ", " << vz << ")" << std::endl;
  58.  
  59. 		// move to start of next vertex
  60. 		seekPos += vertexLength;
  61. 	}
  62.  
  63. 	// cleanup
  64. 	delete vxChar; delete vyChar; delete vzChar;
  65. }
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