setFont from a font loaded from memory crashes program

[ccleung6]

Hi all,

I loaded a font file from memory, then immediately setFont to a sf::Text, but don't know why the program crashes and force to quit.

bool ok = m_font.loadFromMemory(byteArr.data(),byteArr.size()); // byteArr is QByteArray stored in a QMap
if(ok)
{
        qDebug() << "load font from memory ok";
        m_text.setFont(m_font); // call this function crashes program
}else
{
        qDebug() << "load font from memory failed";
}
 

but I use sf::Font::loadFromFile() is OK, draw text correctly

QString path = "....a font file path...";
m_font.loadFromFile(path.toStdString());
m_text.setFont(m_font);
 

where m_font is a sf::Font member variable of a RenderWindow subclass
m_text is sf::Text member variable of the same RenderWindow subclass
the font file used is a Chinese font with size > 5MB

PS: I use Qt 4.7.4 with MinGW

Thanks.

[Laurent]

It works for me.

#include <SFML/Graphics.hpp>
#include <fstream>
#include <vector>

int main()
{
    sf::RenderWindow window(sf::VideoMode(800, 600), "SFML text");

    std::vector<char> buffer;
    std::ifstream file("C:/Windows/Fonts/arial.ttf", std::ios_base::binary);
    file.seekg(0, std::ios_base::end);
    std::streamsize size = file.tellg();
    file.seekg(0, std::ios_base::beg);
    buffer.resize(size);
    file.read(&buffer[0], size);

    sf::Font font;
    if (!font.loadFromMemory(&buffer[0], buffer.size()))
        return -1;

    sf::Text text;
    text.setString("hello world");
    text.setFont(font);

    while (window.isOpen())
    {
        sf::Event event;
        while (window.pollEvent(event))
        {
            if (event.type == sf::Event::Closed)
                window.close();
        }

        window.clear();
        window.draw(text);
        window.display();
    }

    return 0;
}

So can you please post a complete and minimal code that reproduces the problem?

[ccleung6]

Thanks for your reply, Laurent.

I find out the reason.

I should pass a const char* pointer instead just of char* to loadFromMemory(const void *data, std::size_t sizeInBytes)

this works fine

m_font.loadFromMemory(byteArr.constData(),byteArr.size());
 

[Laurent]

Hmm... that's really strange.

[Qix]

Probably a really stupid question, but what happens when you typecast to a (const char*)?