Method offsetFromThumbPosition

source/windowing/StarScrollArea.cpp:232–245

}

Vec2I ScrollBar::offsetFromThumbPosition(Vec2I const& thumbPosition) const {
  auto scrollArea = convert<ScrollArea>(m_parent);
  if (m_direction == GuiDirection::Vertical) {
    int scrollSpan = trackSize() - m_thumb->size()[1];
    int scrollOffset = clamp((thumbPosition[1] - ScrollButtonStackSize), 0, scrollSpan);
    float scrollRatio = (float)scrollOffset / (float)scrollSpan;
    return {scrollArea->scrollOffset()[0], ceil(scrollArea->maxScrollPosition()[1] * scrollRatio)};
  } else {
    int scrollSpan = trackSize() - m_thumb->size()[0];
    int scrollOffset = clamp((thumbPosition[0] - ScrollButtonStackSize), 0, scrollSpan);
    float scrollRatio = (float)scrollOffset / (float)scrollSpan;
    return {(int)ceil(scrollArea->maxScrollPosition()[0] * scrollRatio), scrollArea->scrollOffset()[1]};
  }
}

ScrollArea::ScrollArea() {
  auto assets = Root::singleton().assets();