From 6188e64fc981593bdeba15e62c04008f2d754015 Mon Sep 17 00:00:00 2001
From: schnepe2 <schnepe2@gmx.de>
Date: Thu, 11 Jan 2024 21:41:54 +0100
Subject: [PATCH] Floating point output stream formatter added to serialize
 double/float values nice & tidy.

---
 Src/Orbiter/OrbiterAPI.cpp |  6 ++++--
 Src/Orbiter/Util.cpp       | 34 ++++++++++++++++++++++++++++++++++
 Src/Orbiter/Util.h         | 16 ++++++++++++++++
 3 files changed, 54 insertions(+), 2 deletions(-)

diff --git a/Src/Orbiter/OrbiterAPI.cpp b/Src/Orbiter/OrbiterAPI.cpp
index 9ee9d4f9f..79565f080 100644
--- a/Src/Orbiter/OrbiterAPI.cpp
+++ b/Src/Orbiter/OrbiterAPI.cpp
@@ -2348,13 +2348,15 @@ DLLEXPORT void oapiWriteScenario_int (FILEHANDLE file, char *item, int i)
 DLLEXPORT void oapiWriteScenario_float (FILEHANDLE file, char *item, double d)
 {
 	ofstream &ofs = *(ofstream*)file;
-	ofs << "  " << item << ' ' << d << endl;
+	FltFormat f{ 6 }; // default precision: 6
+	ofs << "  " << item << ' ' << f(d) << endl;
 }
 
 DLLEXPORT void oapiWriteScenario_vec (FILEHANDLE file, char *item, const VECTOR3 &vec)
 {
 	ofstream &ofs = *(ofstream*)file;
-	ofs << "  " << item << ' ' << vec.x << ' ' << vec.y << ' ' << vec.z << endl;
+	FltFormat f{ 6 }; // default precision: 6
+	ofs << "  " << item << ' ' << f(vec.x) << ' ' << f(vec.y) << ' ' << f(vec.z) << endl;
 }
 
 DLLEXPORT bool oapiReadScenario_nextline (FILEHANDLE file, char *&line)
diff --git a/Src/Orbiter/Util.cpp b/Src/Orbiter/Util.cpp
index f251383c3..f7f139d8a 100644
--- a/Src/Orbiter/Util.cpp
+++ b/Src/Orbiter/Util.cpp
@@ -3,6 +3,8 @@
 
 #include "Util.h"
 #include <shlobj.h>
+#include <sstream>
+#include <iomanip>
 
 LONGLONG NameToId (const char *name)
 {
@@ -97,3 +99,35 @@ void SetClientPos (HWND hWnd, HWND hChild, RECT &r)
 	MoveWindow (hChild, r.left, r.top, r.right-r.left, r.bottom-r.top, true);
 }
 
+
+// ------------------------------------------------------------------------------
+// Floating point output stream formatter
+// ------------------------------------------------------------------------------
+
+FltFormatter::FltFormatter (int precision, double value)
+	: precision(precision)
+	, value(value)
+{
+}
+
+std::ostream& operator<< (std::ostream& os, const FltFormatter& v)
+{
+	std::stringstream ss;
+	ss << std::setprecision(v.precision) << std::fixed << v.value;
+	std::string str;
+	ss.str().swap(str);
+	str.resize(str.find_last_not_of("0") + 1);
+//	if (str[str.length() - 1] == '.') { str.resize(str.length() - 1); } // results in "1"   instead of "1."
+	if (str[str.length() - 1] == '.') { str.push_back('0'); }           // results in "1.0" instead of "1."
+	os << str;
+	return os;
+}
+
+FltFormat::FltFormat (int precision /* = 6 */)
+	: precision(precision)
+{
+}
+
+FltFormatter FltFormat::operator() (double value) const {
+	return FltFormatter(precision, value);
+}
\ No newline at end of file
diff --git a/Src/Orbiter/Util.h b/Src/Orbiter/Util.h
index 3cd4ae2c5..4d31c4840 100644
--- a/Src/Orbiter/Util.h
+++ b/Src/Orbiter/Util.h
@@ -72,4 +72,20 @@ double toc(); // stop clock and return value
 RECT GetClientPos (HWND hWnd, HWND hChild);
 void SetClientPos (HWND hWnd, HWND hChild, RECT &r);
 
+// Floating point output stream formatter
+struct FltFormatter
+{
+	int precision;
+	double value;
+	FltFormatter (int precision, double value);
+	friend std::ostream& operator<< (std::ostream& os, const FltFormatter& v);
+};
+
+struct FltFormat
+{
+	int precision;
+	FltFormat (int precision = 6);
+	FltFormatter operator() (double value) const;
+};
+
 #endif //!__UTIL_H
\ No newline at end of file