1 files changed, 148 insertions, 0 deletions
diff --git a/curses/cursesvscroll.C b/curses/cursesvscroll.C
new file mode 100644
index 0000000..f24e2ba
--- /dev/null
+++ b/curses/cursesvscroll.C
@@ -0,0 +1,148 @@
+/*
+** Copyright 2002-2011, Double Precision Inc.
+**
+** See COPYING for distribution information.
+*/
+
+#include "curses_config.h"
+#include "cursesvscroll.H"
+
+CursesVScroll::CursesVScroll(CursesContainer *parent)
+	: CursesContainer(parent), firstRowShown(0)
+{
+}
+
+CursesVScroll::~CursesVScroll()
+{
+}
+
+int CursesVScroll::getCursorPosition(int &row, int &col)
+{
+	scrollTo(row);
+
+	row -= firstRowShown;
+
+	return (CursesContainer::getCursorPosition(row, col));
+}
+
+
+int CursesVScroll::getWidth() const
+{
+	return getScreenWidth();
+}
+
+void CursesVScroll::getVerticalViewport(size_t &first_row,
+					size_t &nrows)
+{
+	first_row=firstRowShown;
+	nrows=getHeight();
+}
+
+void CursesVScroll::erase()
+{
+	size_t w=getWidth(), h=getHeight();
+
+	std::vector<unicode_char> spaces;
+
+	spaces.insert(spaces.end(), w, ' ');
+
+	size_t i;
+
+	for (i=0; i<h; i++)
+		CursesContainer::writeText(spaces, i, 0, CursesAttr());
+}
+
+void CursesVScroll::deleteChild(Curses *child)
+{
+	CursesContainer::deleteChild(child);
+	scrollTo(0);
+}
+
+void CursesVScroll::scrollTo(size_t row)
+{
+	size_t h=getHeight();
+
+#if 0
+	if (row < 0 || (size_t)row < h)
+	{
+		if (firstRowShown > 0)
+		{
+			firstRowShown=0;
+			redraw();
+		}
+	}
+	else
+#endif
+		if ((size_t)row < firstRowShown)
+	{
+		if (row + 1 < firstRowShown)
+			firstRowShown=row;
+		else
+		{
+			if (h > 6)
+			{
+				firstRowShown=row+5;
+				
+				if (firstRowShown >= h)
+					firstRowShown -= h;
+				else
+					firstRowShown=0;
+			}
+			else
+				firstRowShown=row;
+		}
+		redraw();
+	}
+	else if ((size_t)row >= firstRowShown + h)
+	{
+		if (firstRowShown + h < (size_t)row)
+		{
+			firstRowShown=row + 1 - h;
+		}
+		else
+		{
+			if (h > 6)
+				firstRowShown=row-5;
+			else
+				firstRowShown=row + 1 - h;
+		}
+		redraw();
+	}
+}
+
+bool CursesVScroll::writeText(const char *text, int row, int col,
+			      const CursesAttr &attr) const
+{
+	if (row < 0 ||
+	    (size_t)row < firstRowShown ||
+	    (size_t)row >= firstRowShown + getHeight())
+		return false; // This row is not shown
+
+	row -= firstRowShown;
+
+	return CursesContainer::writeText(text, row, col, attr);
+}
+
+bool CursesVScroll::writeText(const std::vector<unicode_char> &text,
+			      int row, int col,
+			      const Curses::CursesAttr &attr) const
+{
+	if (row < 0 ||
+	    (size_t)row < firstRowShown ||
+	    (size_t)row >= firstRowShown + getHeight())
+		return false; // Ditto.
+
+	row -= firstRowShown;
+
+	return CursesContainer::writeText(text, row, col, attr);
+}
+
+//
+// We just logically scrolled.  Clear the window, redraw.
+//
+
+void CursesVScroll::redraw()
+{
+	erase();
+	draw();
+}