C++ (Cpp) Box2d::inflate Examples

Example #1

File: Step2View.cpp Project: thinkfeed/touchvg

void CScrollShapeView::OnZoomed()
{
    CRandomShapeView::OnZoomed();

    Box2d rect;

    // m_rcLimits: 极限范围对应的坐标范围, 像素
    rect = m_shapes->getExtent() * m_graph->xf.modelToDisplay();
    rect.inflate(1, 1);
    rect.get(m_rcLimits);

    // m_rcScrWnd: 当前窗口对应的坐标范围, 像素
    rect = Box2d(m_graph->xf.getCenterW(),
        m_graph->xf.getWidth() / m_graph->xf.getWorldToDisplayX(),
        m_graph->xf.getHeight() / m_graph->xf.getWorldToDisplayY());
    rect *= m_graph->xf.worldToDisplay();
    rect.get(m_rcScrWnd);

    // 以m_rcLimits左上角为原点调整m_rcScrWnd和m_rcLimits
    ::OffsetRect(&m_rcScrWnd, -m_rcLimits.left, -m_rcLimits.top);
    ::OffsetRect(&m_rcLimits, -m_rcLimits.left, -m_rcLimits.top);

    // 避免m_rcScrWnd部分超出m_rcLimits
    ::UnionRect(&m_rcLimits, &m_rcLimits, &m_rcScrWnd);

    SCROLLINFO si;
    si.cbSize = sizeof(si);
    si.fMask = SIF_RANGE | SIF_PAGE | SIF_POS;
    si.nMin = 0;

    if (m_rcLimits.right - m_rcLimits.left > m_rcScrWnd.right - m_rcScrWnd.left)
    {
        si.nMax = max(1, m_rcLimits.right - m_rcLimits.left);
        si.nPage = m_rcScrWnd.right - m_rcScrWnd.left;
        si.nPos = m_rcScrWnd.left;
        ::EnableScrollBar(m_hWnd, SB_HORZ, ESB_ENABLE_BOTH);
        ::SetScrollInfo(m_hWnd, SB_HORZ, &si, TRUE);
    }
    else
    {
        ::EnableScrollBar(m_hWnd, SB_HORZ, ESB_DISABLE_BOTH);
    }

    if (m_rcLimits.bottom - m_rcLimits.top > m_rcScrWnd.bottom - m_rcScrWnd.top)
    {
        si.nMax = max(1, m_rcLimits.bottom - m_rcLimits.top);
        si.nPage = m_rcScrWnd.bottom - m_rcScrWnd.top;
        si.nPos = m_rcScrWnd.top;
        ::EnableScrollBar(m_hWnd, SB_VERT, ESB_ENABLE_BOTH);
        ::SetScrollInfo(m_hWnd, SB_VERT, &si, TRUE);
    }
    else
    {
        ::EnableScrollBar(m_hWnd, SB_VERT, ESB_DISABLE_BOTH);
    }
}