Increased gorgonsub's ASS write speed with large files 3.5x by getting rid of wxString conversion and concatenation routines and writing my own.

Originally committed to SVN as r2059.

aegilib/include/aegilib/utils.h

@@ -80,4 +80,16 @@ namespace Gorgonsub {
 	String IntegerToString(int value);
 	String PrettySize(int bytes);
 
+	// Fast string write
+	inline void WriteText(wxChar *&dst,const wxChar *src,size_t len,size_t &pos) {
+		memcpy(dst,src,len*sizeof(wxChar));
+		dst += len;
+		pos += len;
+	}
+	inline void WriteChar(wxChar *&dst,const wxChar &src,size_t &pos) {
+		*dst = src;
+		dst++;
+		pos++;
+	}
+	void WriteNumber(wxChar *&dst,wxChar *temp,int number,int pad,size_t &pos);
 };

aegilib/src/formats/format_ass_dialogue.cpp

@@ -140,31 +140,92 @@ bool DialogueASS::Parse(wxString rawData, int version)
 // Serialize
 String DialogueASS::ToText(int version) const
 {
-	// Prepare
+	// Old, slow code
-	wxString final = _T("");
+	if (false) {
+		// Prepare
+		wxString final;
 
-	// Write comment or dialogue
+		// Write comment or dialogue
-	if (isComment) final = _T("Comment: ");
+		if (isComment) final = _T("Comment: ");
-	else final = _T("Dialogue: ");
+		else final = _T("Dialogue: ");
 
-	// Write layer or marked
+		// Write layer or marked
-	if (version >= 1) final += wxString::Format(_T("%01i,"),layer);
+		if (version >= 1) final += wxString::Format(_T("%01i,"),layer);
-	else final += _T("Marked=0,");
+		else final += _T("Marked=0,");
 
-	// Write times, style and actor
+		// Write times, style and actor
-	final += start.GetString(2,1) + _T(",") + end.GetString(2,1) + _T(",") + style + _T(",") + actor + _T(",");
+		final += start.GetString(2,1) + _T(",") + end.GetString(2,1) + _T(",") + style + _T(",") + actor + _T(",");
 
-	// Write margins
+		// Write margins
-	if (version <= 1) final += wxString::Format(_T("%04i,%04i,%04i,"),margin[0],margin[1],margin[2]);
+		if (version <= 1) final += wxString::Format(_T("%04i,%04i,%04i,"),margin[0],margin[1],margin[2]);
-	else final += wxString::Format(_T("%04i,%04i,%04i,%04i,"),margin[0],margin[1],margin[2],margin[3]);
+		else final += wxString::Format(_T("%04i,%04i,%04i,%04i,"),margin[0],margin[1],margin[2],margin[3]);
 
-	// Write effect and text
+		// Write effect and text
-	final += effect + _T(",") + text;
+		final += effect + _T(",") + text;
 
-	// Make sure that final has no line breaks
+		// Return final
-	final.Replace(_T("\n"),_T(""));
+		return final;
-	final.Replace(_T("\r"),_T(""));
+	}
 
-	// Return final
+	// New, faster code
-	return final;
+	else {
+		// Calculate size
+		size_t size = 9+9+20+12+12;			// 9 for "comment: " (+1 for dialogue below), 9 for commas,
+											// 20 for times, 12 for margins, 12 just to be sure that layer fits
+		if (!isComment) size++;				// Comment->Dialogue
+		if (version == 0) size += 8;		// "Marked=0"
+		else if (version == 2) size += 5;	// Fourth margin
+		size += style.Length() + actor.Length() + effect.Length() + text.Length();
+
+		// Allocate string
+		wxString final;
+		wxChar *buffer = final.GetWriteBuf(size);
+		wxChar temp[16];
+
+		// Write comment/dialogue
+		size_t pos = 0;
+		if (isComment) WriteText(buffer,_T("Comment: "),9,pos);
+		else WriteText(buffer,_T("Dialogue: "),10,pos);
+
+		// Write layer or marked
+		if (version >= 1) {
+			WriteNumber(buffer,temp,layer,0,pos);
+			WriteChar(buffer,_T(','),pos);
+		}
+		else WriteText(buffer,_T("Marked=0,"),9,pos);
+
+		// Write times
+		wxString tempStr = start.GetString(2,1);
+		WriteText(buffer,&tempStr[0],10,pos);
+		WriteChar(buffer,_T(','),pos);
+		tempStr = end.GetString(2,1);
+		WriteText(buffer,&tempStr[0],10,pos);
+		WriteChar(buffer,_T(','),pos);
+
+		// Write style and actor
+		WriteText(buffer,&style[0],style.Length(),pos);
+		WriteChar(buffer,_T(','),pos);
+		WriteText(buffer,&actor[0],actor.Length(),pos);
+		WriteChar(buffer,_T(','),pos);
+
+		// Write margins
+		size_t marCount = 3;
+		if (version == 2) marCount++;
+		for (size_t i=0;i<marCount;i++) {
+			WriteNumber(buffer,temp,margin[i],4,pos);
+			WriteChar(buffer,_T(','),pos);
+		}
+
+		// Write effect and text
+		WriteText(buffer,&effect[0],effect.Length(),pos);
+		WriteChar(buffer,_T(','),pos);
+		WriteText(buffer,&text[0],text.Length(),pos);
+
+		// Write terminator
+		WriteText(buffer,_T("\0"),1,pos);
+
+		// Restore string's state
+		final.UngetWriteBuf(pos-1);
+		return final;
+	}
 }

aegilib/src/text_file_reader.cpp

@@ -54,7 +54,7 @@ TextFileReader::TextFileReader(wxInputStream &stream,Gorgonsub::String enc,bool
 {
 	// Setup
 	trim = _trim;
-	threaded = prefetch;
+	threaded = prefetch && false;
 	thread = NULL;
 
 	// Set encoding
@@ -68,6 +68,8 @@ TextFileReader::TextFileReader(wxInputStream &stream,Gorgonsub::String enc,bool
 // Destructor
 TextFileReader::~TextFileReader()
 {
+	wxCriticalSectionLocker locker(mutex);
+	if (thread) thread->Delete();
 }
 
 
@@ -182,6 +184,7 @@ Gorgonsub::String TextFileReader::ActuallyReadLine()
 // Checks if there's more to read
 bool TextFileReader::HasMoreLines()
 {
+	if (cache.size()) return true;
 	wxCriticalSectionLocker locker(mutex);
 	return (!file.Eof());
 }
@@ -217,12 +220,13 @@ String TextFileReader::ReadLineFromFile()
 
 	// Load into cache if needed
 	String final;
-	if (cache.size() == 0) {
+	{
 		wxCriticalSectionLocker locker(mutex);
-		cache.push_back(ActuallyReadLine());
+		if (cache.size() == 0) {
+			cache.push_back(ActuallyReadLine());
+		}
 	}
 
-	bool startThread = false;
 	{
 		// Retrieve from cache
 		wxCriticalSectionLocker locker(mutex);
@@ -234,16 +238,11 @@ String TextFileReader::ReadLineFromFile()
 		// Start the thread to prefetch more
 		if (cache.size() < 3 && thread == NULL) {
 			thread = new PrefetchThread(this);
-			startThread = true;
+			thread->Create();
+			thread->Run();
 		}
 	}
 
-	// Starts the thread
-	if (startThread) {
-		thread->Create();
-		thread->Run();
-	}
-
 	return final;
 }
 
@@ -253,21 +252,27 @@ String TextFileReader::ReadLineFromFile()
 wxThread::ExitCode PrefetchThread::Entry()
 {
 	// Lock
-	wxCriticalSectionLocker locker(parent->mutex);
+	bool run = true;
-	while (parent->cache.size() < 3 && !parent->file.Eof()) {
+	while (run) {
-		// So I need to do this for whatever reason
 		if (TestDestroy()) {
 			parent->thread = NULL;
 			return 0;
 		}
-
+		{
-		// Get line
+			wxCriticalSectionLocker locker(parent->mutex);
-		parent->cache.push_back(parent->ActuallyReadLine());
+			if (parent->cache.size() < 6) {
+				if (!parent->file.Eof()) {
+					// Get line
+					parent->cache.push_back(parent->ActuallyReadLine());
+				}
+				else run = false;
+			}
+		}
+		Sleep(50);
 	}
 
 	// Die
-	//wxCriticalSectionLocker locker(parent->mutex);
+	wxCriticalSectionLocker locker(parent->mutex);
 	parent->thread = NULL;
-	Delete();
 	return 0;
 }

aegilib/src/text_file_reader.h

@@ -64,7 +64,7 @@ namespace Gorgonsub {
 		String ActuallyReadLine();
 
 	public:
-		TextFileReader(wxInputStream &stream,String encoding=_T(""),bool trim=true,bool prefetch=false);
+		TextFileReader(wxInputStream &stream,String encoding=_T(""),bool trim=true,bool prefetch=true);
 		~TextFileReader();
 
 		String ReadLineFromFile();

aegilib/src/time.cpp

@@ -67,14 +67,43 @@ String Time::GetString(int ms_precision,int h_precision) const
 	else if (ms_precision == 1) _ms /= 100;
 	else if (ms_precision == 0) _ms = 0;
 
-	// Generate mask string
+	// Old code
-	wxString mask = wxString::Format(_T("%%0%ii:%%0%ii:%%0%ii.%%0%ii"),h_precision,2,2,ms_precision);
+	if (false) {
+		// Generate mask string
+		wxString mask = wxString::Format(_T("%%0%ii:%%0%ii:%%0%ii.%%0%ii"),h_precision,2,2,ms_precision);
 
-	// Generate final string
+		// Generate final string
-	wxString final = wxString::Format(mask,h,min,s,_ms);
+		wxString final = wxString::Format(mask,h,min,s,_ms);
 
-	// Done
+		// Done
-	return final;
+		return final;
+	}
+
+	// New code
+	else {
+		// Get write buffer
+		wxString final;
+		size_t size = 7+h_precision+ms_precision;
+		size_t pos = 0;
+		wxChar *buffer = final.GetWriteBuf(size);
+		wxChar temp[16];
+
+		// Write time
+		WriteNumber(buffer,temp,h,h_precision,pos);
+		WriteChar(buffer,_T(':'),pos);
+		WriteNumber(buffer,temp,min,2,pos);
+		WriteChar(buffer,_T(':'),pos);
+		WriteNumber(buffer,temp,s,2,pos);
+		WriteChar(buffer,_T('.'),pos);
+		WriteNumber(buffer,temp,_ms,ms_precision,pos);
+
+		// Write terminator
+		WriteText(buffer,_T("\0"),1,pos);
+
+		// Restore string's state and return
+		final.UngetWriteBuf(pos-1);
+		return final;
+	}
 }
 
 

aegilib/src/utils.cpp

@@ -82,3 +82,33 @@ String Gorgonsub::FloatToString(double value) {
 String Gorgonsub::IntegerToString(int value) {
 	return wxString::Format(_T("%i"),value);
 }
+
+
+////////////////////////////
+// Fast writing to a string
+void Gorgonsub::WriteNumber(wxChar *&dst,wxChar *temp,int number,int pad,size_t &pos) {
+	// Write number backwards first
+	int div, value;
+	size_t len;
+	for (len=0;true;len++) {
+		div = number / 10;
+		value = number - (div*10);
+		temp[len] = (wxChar) (value + '0');
+		if (!div) break;
+		number = div;
+	}
+	len++;
+
+	// Pad with zeroes
+	pad -= (int)len;
+	for (int i=0;i<pad;i++) {
+		*dst++ = (wxChar) '0';
+		pos++;
+	}
+
+	// Write number
+	for (size_t i=0;i<len;i++) {
+		*dst++ = temp[len-i-1];
+		pos++;
+	}
+}

aegilib/test/src/main.cpp

@@ -40,7 +40,8 @@
 #include "text_file_reader.h"
 #include "text_file_writer.h"
 
-int main () {
+
+int main() {
 	using namespace std;
 	using namespace Gorgonsub;
 
@@ -111,4 +112,6 @@ int main () {
 	catch (std::exception &e) {
 		cout << "\n\nException: " << e.what() << endl << endl;
 	}
+
+	return true;
 }

aegilib/test/test.vcproj

@@ -118,7 +118,7 @@
 			<Tool
 				Name="VCCLCompilerTool"
 				AdditionalIncludeDirectories="../include"
-				PreprocessorDefinitions="WIN32;NDEBUG;_CONSOLE"
+				PreprocessorDefinitions="WIN32;NDEBUG;_WINDOWS"
 				RuntimeLibrary="2"
 				UsePrecompiledHeader="0"
 				WarningLevel="4"