Avoid string allocations during text rendering and sizing

Now a text chunk has a maximum length of 4k characters, but that should
be plenty of space since they're only single lines.

3 files changed, 11 insertions, 16 deletions

diff --git a/src/gui/truetypefont.cpp b/src/gui/truetypefont.cpp
index 167a66b2..adb49780 100644
--- a/src/gui/truetypefont.cpp
+++ b/src/gui/truetypefont.cpp
@@ -26,13 +26,22 @@
 
 #include "resources/image.h"
 
-#include "utils/stringutils.h"
-
 #include <guichan/color.hpp>
 #include <guichan/exception.hpp>
 
 const unsigned int CACHE_SIZE = 256;
 
+static const char *getSafeUtf8String(const std::string &text)
+{
+    static int UTF8_MAX_SIZE = 10;
+
+    static char buf[4096];
+    const int len = std::min(text.size(), sizeof(buf) - UTF8_MAX_SIZE);
+    memcpy(buf, text.c_str(), len);
+    memset(buf + len, 0, UTF8_MAX_SIZE);
+    return buf;
+}
+
 class TextChunk
 {
     public:
@@ -62,7 +71,6 @@ class TextChunk
             const char *str = getSafeUtf8String(text);
             SDL_Surface *surface = TTF_RenderUTF8_Blended(
                     font, str, sdlCol);
-            delete[] str;
 
             if (!surface)
             {
@@ -180,7 +188,6 @@ int TrueTypeFont::getWidth(const std::string &text) const
     int w, h;
     const char *str = getSafeUtf8String(text);
     TTF_SizeUTF8(mFont, str, &w, &h);
-    delete[] str;
     return w;
 }
 
diff --git a/src/utils/stringutils.cpp b/src/utils/stringutils.cpp
index 7a951ec6..d9c65dd7 100644
--- a/src/utils/stringutils.cpp
+++ b/src/utils/stringutils.cpp
@@ -28,8 +28,6 @@
 #include <cstdarg>
 #include <cstdio>
 
-static int UTF8_MAX_SIZE = 10;
-
 std::string &trim(std::string &str)
 {
     std::string::size_type pos = str.find_last_not_of(' ');
@@ -170,14 +168,6 @@ std::string findSameSubstring(const std::string &str1,
     return str1.substr(0, minLength);
 }
 
-const char *getSafeUtf8String(const std::string &text)
-{
-    char *buf = new char[text.size() + UTF8_MAX_SIZE];
-    memcpy(buf, text.c_str(), text.size());
-    memset(buf + text.size(), 0, UTF8_MAX_SIZE);
-    return buf;
-}
-
 bool getBoolFromString(const std::string &text, bool def)
 {
     std::string a = text;
diff --git a/src/utils/stringutils.h b/src/utils/stringutils.h
index 8e5f1102..b394e29f 100644
--- a/src/utils/stringutils.h
+++ b/src/utils/stringutils.h
@@ -136,8 +136,6 @@ bool isWordSeparator(char chr);
 std::string findSameSubstring(const std::string &str1,
                               const std::string &str2);
 
-const char *getSafeUtf8String(const std::string &text);
-
 /**
  * Returns a bool value depending on the given string value.
  *