+ int widthsAbove = Math.max(0, visibleWidths - 2);
+ int ypos = wrappedRepeatHeightPx * widthsAbove
+ + wrappedSpaceAboveAlignment;
+ int endRes = ranges.getEndRes();
+ endRes += widthsAbove * viewportWidth;
+ int startRes = endRes - columns;
+ int xOffset = ((startRes - ranges.getStartRes()) % viewportWidth)
+ * charWidth;
+
+ /*
+ * white fill first to erase annotations
+ */
+ gg.translate(xOffset, 0);
+ gg.setColor(Color.white);
+ gg.fillRect(labelWidthWest, ypos,
+ (endRes - startRes + 1) * charWidth, wrappedRepeatHeightPx);
+ gg.translate(-xOffset, 0);
+
+ drawWrappedWidth(gg, ypos, startRes, endRes, canvasHeight);
+ }
+
+ /*
+ * draw newly visible columns in last wrapped width (none if we
+ * have reached the end of the alignment)
+ * y-offset for drawing last width is height of widths above,
+ * plus one gap row
+ */
+ int widthsAbove = visibleWidths - 1;
+ int ypos = wrappedRepeatHeightPx * widthsAbove
+ + wrappedSpaceAboveAlignment;
+ int endRes = ranges.getEndRes();
+ endRes += widthsAbove * viewportWidth;
+ int startRes = endRes - columns + 1;
+
+ /*
+ * white fill first to erase annotations
+ */
+ int xOffset = ((startRes - ranges.getStartRes()) % viewportWidth)
+ * charWidth;
+ gg.translate(xOffset, 0);
+ gg.setColor(Color.white);
+ int width = viewportWidth * charWidth - xOffset;
+ gg.fillRect(labelWidthWest, ypos, width, wrappedRepeatHeightPx);
+ gg.translate(-xOffset, 0);
+
+ gg.setFont(av.getFont());
+ gg.setColor(Color.black);
+
+ if (startRes < ranges.getVisibleAlignmentWidth())
+ {
+ drawWrappedWidth(gg, ypos, startRes, endRes, canvasHeight);
+ }
+
+ /*
+ * and finally, white fill any space below the visible alignment
+ */
+ int heightBelow = canvasHeight - visibleWidths * wrappedRepeatHeightPx;
+ if (heightBelow > 0)
+ {
+ gg.setColor(Color.white);
+ gg.fillRect(0, canvasHeight - heightBelow, getWidth(), heightBelow);
+ }
+ }
+
+ /**
+ * Shifts the visible alignment by the specified number of columns - left if
+ * negative, right if positive. Copies and moves sequences and annotations (if
+ * shown). Scales, hidden column markers and any newly visible columns must be
+ * drawn separately.
+ *
+ * @param positions
+ */
+ protected void shiftWrappedAlignment(int positions)
+ {
+ if (positions == 0)
+ {
+ return;
+ }
+ int charWidth = av.getCharWidth();
+
+ int canvasHeight = getHeight();
+ ViewportRanges ranges = av.getRanges();
+ int viewportWidth = ranges.getViewportWidth();
+ int widthToCopy = (ranges.getViewportWidth() - Math.abs(positions))
+ * charWidth;
+ int heightToCopy = wrappedRepeatHeightPx - wrappedSpaceAboveAlignment;
+ int xMax = ranges.getVisibleAlignmentWidth();
+
+ if (positions > 0)
+ {
+ /*
+ * shift right (after scroll left)
+ * for each wrapped width (starting with the last), copy (width-positions)
+ * columns from the left margin to the right margin, and copy positions
+ * columns from the right margin of the row above (if any) to the
+ * left margin of the current row
+ */
+
+ /*
+ * get y-offset of last wrapped width, first row of sequences
+ */
+ int y = canvasHeight / wrappedRepeatHeightPx * wrappedRepeatHeightPx;
+ y += wrappedSpaceAboveAlignment;
+ int copyFromLeftStart = labelWidthWest;
+ int copyFromRightStart = copyFromLeftStart + widthToCopy;
+
+ while (y >= 0)