Function InputTextLineIndexGetPosOffset

external/imgui/imgui_widgets.cpp:4677–4693

}

static ImVec2 InputTextLineIndexGetPosOffset(ImGuiContext& g, ImGuiInputTextState* state, ImGuiTextIndex* line_index, const char* buf, const char* buf_end, int cursor_n)
{
    const char* cursor_ptr = buf + cursor_n;
    int* it_begin = line_index->Offsets.begin();
    int* it_end = line_index->Offsets.end();
    const int* it = ImLowerBound(it_begin, it_end, cursor_n);
    if (it > it_begin)
        if (it == it_end || *it != cursor_n || (state != NULL && state->WrapWidth > 0.0f && state->LastMoveDirectionLR == ImGuiDir_Right && cursor_ptr[-1] != '\n' && cursor_ptr[-1] != 0))
            it--;

    const int line_no = (it == it_begin) ? 0 : line_index->Offsets.index_from_ptr(it);
    const char* line_start = line_index->get_line_begin(buf, line_no);
    ImVec2 offset;
    offset.x = InputTextCalcTextSize(&g, line_start, cursor_ptr, buf_end, NULL, NULL, ImDrawTextFlags_WrapKeepBlanks).x;
    offset.y = (line_no + 1) * g.FontSize;
    return offset;
}

// Edit a string of text
// - buf_size account for the zero-terminator, so a buf_size of 6 can hold "Hello" but not "Hello!".