add lab3

lab3/grid2off.cpp

@@ -0,0 +1,76 @@
+// Convert 2D grid of points to Geomview .off file of quadrilaterals.
+
+#include <iostream>
+#include <string>
+
+#include "grid2DPoints3D.h"
+#include "grid2DIO.h"
+#include "writeGrid2DOFF.h"
+
+
+// ********************* Functions ************************************
+
+/// Replace the file extension of infilename with ".off".
+std::string CreateOutFilename(const std::string& infilename) {
+    size_t dot_pos = infilename.rfind('.');
+    std::string basename;
+    if (dot_pos != std::string::npos) {
+        basename = infilename.substr(0, dot_pos);
+    }
+    else {
+        basename = infilename;
+    }
+    return basename + ".off";
+}
+
+
+void UsageMsg(const std::string& command_name) {
+    std::cerr << "Usage: " << command_name
+              << " {input filename} [{output filename}]\n";
+}
+
+
+// ********************* Main *****************************************
+
+int main(int argc, char* argv[]) {
+
+    if (argc == 1) {
+        UsageMsg(argv[0]);
+        return 0;
+    }
+
+    std::string infilename = argv[1];
+    GRID2D_POINTS3D grid2D;
+
+    try {
+        OpenReadGrid2DPoints3D(infilename, grid2D);
+    }
+    catch (const std::exception&) {
+        std::cerr << "Exiting...\n";
+        return -1;
+    }
+
+    std::string outfilename;
+    if (argc < 3) {
+        outfilename = CreateOutFilename(infilename);
+    }
+    else {
+        outfilename = argv[2];
+    }
+
+    WRITE_GRID2D_OFF writeOFF;
+    std::vector<std::string> comments_list =
+        {"File created from 2D grid of points."};
+
+    try {
+        std::cout << "Writing file " << outfilename << ".\n";
+        writeOFF.OpenAndWrite(outfilename, grid2D, comments_list);
+    }
+    catch (const std::exception& e) {
+        std::cerr << e.what() << "\n";
+        std::cerr << "Exiting...\n";
+        return -1;
+    }
+
+    return 0;
+}