bool CGUIFont::UpdateScrollInfo(const vecText &text, CScrollInfo &scrollInfo)
{
// draw at our scroll position
// we handle the scrolling as follows:
// We scroll on a per-pixel basis (eschewing the use of character indices
// which were also in use previously). The complete string, including suffix,
// is plotted to achieve the desired effect - normally just the one time, but
// if there is a wrap point within the viewport then it will be plotted twice.
// If the string is smaller than the viewport, then it may be plotted even
// more times than that.
//
if (g_application.ScreenSaverDisablesAutoScrolling())
return false;
if (scrollInfo.waitTime)
{
scrollInfo.waitTime--;
return false;
}
if (text.empty())
return false;
CScrollInfo old(scrollInfo);
// move along by the appropriate scroll amount
float scrollAmount = fabs(scrollInfo.GetPixelsPerFrame() * g_graphicsContext.GetGUIScaleX());
if (!scrollInfo.m_widthValid)
{
/* Calculate the pixel width of the complete string */
scrollInfo.m_textWidth = GetTextWidth(text);
scrollInfo.m_totalWidth = scrollInfo.m_textWidth + GetTextWidth(scrollInfo.suffix);
scrollInfo.m_widthValid = true;
}
scrollInfo.pixelPos += scrollAmount;
assert(scrollInfo.m_totalWidth != 0);
while (scrollInfo.pixelPos >= scrollInfo.m_totalWidth)
scrollInfo.pixelPos -= scrollInfo.m_totalWidth;
if (scrollInfo.pixelPos != old.pixelPos)
return true;
else
return false;
}
