Method appendfv

tutorials/common/imgui/imgui.cpp:2512–2536

Helper: Text buffer for logging/accumulating text

// Helper: Text buffer for logging/accumulating text
void ImGuiTextBuffer::appendfv(const char* fmt, va_list args)
{
    va_list args_copy;
    va_copy(args_copy, args);

    int len = ImFormatStringV(NULL, 0, fmt, args);         // FIXME-OPT: could do a first pass write attempt, likely successful on first pass.
    if (len <= 0)
    {
        va_end(args_copy);
        return;
    }

    // Add zero-terminator the first time
    const int write_off = (Buf.Size != 0) ? Buf.Size : 1;
    const int needed_sz = write_off + len;
    if (write_off + len >= Buf.Capacity)
    {
        int new_capacity = Buf.Capacity * 2;
        Buf.reserve(needed_sz > new_capacity ? needed_sz : new_capacity);
    }

    Buf.resize(needed_sz);
    ImFormatStringV(&Buf[write_off - 1], (size_t)len + 1, fmt, args_copy);
    va_end(args_copy);
}

void ImGuiTextIndex::append(const char* base, int old_size, int new_size)
{