Method Load

source/common/models/models_obj.cpp:38–234

* Load an OBJ model * * @param fn The path to the model file * @param lumpnum The lump index in the wad collection * @param buffer The contents of the model file * @param length The size of the model file * @return Whether or not the model was parsed successfully */

 * @return Whether or not the model was parsed successfully
 */
bool FOBJModel::Load(const char* fn, int lumpnum, const char* buffer, int length)
{
	auto objName = fileSystem.GetFileFullPath(lumpnum);
	FString objBuf(buffer, length);

	// Do some replacements before we parse the OBJ string
	{
		// Ensure usemtl statements remain intact
		TArray<FString> mtlUsages;
		TArray<ptrdiff_t> mtlUsageIdxs;
		ptrdiff_t bpos = 0, nlpos = 0, slashpos = 0;
		while (1)
		{
			bpos = objBuf.IndexOf("\nusemtl", bpos);
			if (bpos == -1) break;
			slashpos = objBuf.IndexOf('/', bpos);
			nlpos = objBuf.IndexOf('\n', ++bpos);
			if (slashpos > nlpos || slashpos == -1)
			{
				continue;
			}
			if (nlpos == -1)
			{
				nlpos = objBuf.Len();
			}
			FString lineStr(objBuf.GetChars() + bpos, nlpos - bpos);
			mtlUsages.Push(lineStr);
			mtlUsageIdxs.Push(bpos);
		}

		// Replace forward slashes with percent signs so they aren't parsed as line comments
		objBuf.ReplaceChars('/', *newSideSep);
		char* wObjBuf = objBuf.LockBuffer();

		// Substitute broken usemtl statements with old ones
		for (size_t i = 0; i < mtlUsages.Size(); i++)
		{
			bpos = mtlUsageIdxs[i];
			nlpos = objBuf.IndexOf('\n', bpos);
			if (nlpos == -1)
			{
				nlpos = objBuf.Len();
			}
			memcpy(wObjBuf + bpos, mtlUsages[i].GetChars(), nlpos - bpos);
		}

		bpos = 0;
		// Find each OBJ line comment, and convert each to a C-style line comment
		while (1)
		{
			bpos = objBuf.IndexOf('#', bpos);
			if (bpos == -1) break;
			if (objBuf[(unsigned int)bpos + 1] == '\n')
			{
				wObjBuf[bpos] = ' ';
			}
			else
			{