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Merge pull request #5047 from chennes/lgtmMeshEmptyBlocks

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[Mesh] Implement high-precision NASTRAN GRID* element
This commit is contained in:
Chris Hennes
2021-09-22 09:22:48 -05:00
committed by GitHub
parent fc83fd1fc8 f9f08f8805
commit e233ba54e6
1 changed files with 67 additions and 8 deletions
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75
src/Mod/Mesh/App/Core/MeshIO.cpp
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@@ -49,6 +49,8 @@
#include <boost/regex.hpp>
#include <boost/algorithm/string.hpp>
#include <boost/lexical_cast.hpp>
#include <boost/convert.hpp>
#include <boost/convert/spirit.hpp>
using namespace MeshCore;
@@ -1656,31 +1658,88 @@ bool MeshInput::LoadNastran (std::istream &rstrIn)
while (std::getline(rstrIn, line)) {
upper(ltrim(line));
if (line.find("GRID*") == 0) {
if (line.empty()) {
// Skip all the following tests
}
else if (line.find('*') == 0) {
else if (line.rfind("GRID*", 0) == 0) {
// This element is the 16-digit-precision GRID element, which occupies two lines of the card. Note that
// FreeCAD discards the extra precision, downcasting to an four-byte float.
//
// The two lines are:
// 1 8 24 40 56
// GRID* Index(16) Blank(16) x(16) y(at least one)
// * z(at least one)
//
// The first character is typically the sign, and may be omitted for positive numbers,
// so it is possible for a field to begin with a blank. Trailing zeros may be omitted, so
// a field may also end with blanks. No space or other delimiter is required between
// the numbers. The following is a valid NASTRAN GRID* element:
//
// GRID* 1 0.1234567890120.
// * 1.
//
if (line.length() < 8 + 16 + 16 + 16 + 1) // Element type(8), index(16), empty(16), x(16), y(>=1)
continue;
auto indexView = std::string_view(&line[8], 16);
auto blankView = std::string_view(&line[8+16], 16);
auto xView = std::string_view(&line[8+16+16], 16);
auto yView = std::string_view(&line[8+16+16+16]);
std::string line2;
std::getline(rstrIn, line2);
if ((!line2.empty() && line2[0] != '*') ||
line2.length() < 9)
continue; // File format error: second line is not a continuation line
auto zView = std::string_view(&line2[8]);
// We have to strip off any whitespace (technically really just any *trailing* whitespace):
auto indexString = boost::trim_copy(std::string(indexView));
auto xString = boost::trim_copy(std::string(xView));
auto yString = boost::trim_copy(std::string(yView));
auto zString = boost::trim_copy(std::string(zView));
auto converter = boost::cnv::spirit();
auto indexCheck = boost::convert<int>(indexString, converter);
if (!indexCheck.is_initialized())
// File format error: index couldn't be converted to an integer
continue;
index = indexCheck.get();
// Get the high-precision versions first
auto x = boost::convert<double>(xString, converter);
auto y = boost::convert<double>(yString, converter);
auto z = boost::convert<double>(zString, converter);
if (!x.is_initialized() || !y.is_initialized() || !z.is_initialized())
// File format error: x, y or z could not be converted
continue;
// Now drop precision:
mNode[index].x = (float)x.get();
mNode[index].y = (float)y.get();
mNode[index].z = (float)z.get();
}
// insert the read-in vertex into a map to preserve the order
else if (line.find("GRID") == 0) {
else if (line.rfind("GRID", 0) == 0) {
if (boost::regex_match(line.c_str(), what, rx_p)) {
// insert the read-in vertex into a map to preserve the order
index = std::atol(what[1].first)-1;
mNode[index].x = (float)std::atof(what[2].first);
mNode[index].y = (float)std::atof(what[5].first);
mNode[index].z = (float)std::atof(what[8].first);
}
}
// insert the read-in triangle into a map to preserve the order
else if (line.find("CTRIA3 ") == 0) {
else if (line.rfind("CTRIA3 ", 0) == 0) {
if (boost::regex_match(line.c_str(), what, rx_t)) {
// insert the read-in triangle into a map to preserve the order
index = std::atol(what[1].first)-1;
mTria[index].iV[0] = std::atol(what[3].first)-1;
mTria[index].iV[1] = std::atol(what[4].first)-1;
mTria[index].iV[2] = std::atol(what[5].first)-1;
}
}
// insert the read-in quadrangle into a map to preserve the order
else if (line.find("CQUAD4") == 0) {
else if (line.rfind("CQUAD4", 0) == 0) {
if (boost::regex_match(line.c_str(), what, rx_q)) {
// insert the read-in quadrangle into a map to preserve the order
index = std::atol(what[1].first)-1;
mQuad[index].iV[0] = std::atol(what[3].first)-1;
mQuad[index].iV[1] = std::atol(what[4].first)-1;