28 #define	UPDATE_SCREEN	0x02			/* Flush to screen. */
35  *	Repaint selected lines from the screen.
74 	 * 1: Refresh the screen.  in vs_refresh()
76 	 * If SC_SCR_REDRAW is set in the current screen, repaint everything  in vs_refresh()
108 	 * 3: Refresh the current screen.  in vs_refresh()
110 	 * Always refresh the current screen, it may be a cursor movement.  in vs_refresh()
112 	 * in the current screen only, and the screen won't flash.  in vs_refresh()
141 	 * A side-effect of refreshing the screen is that it's now ready  in vs_refresh()
150  *	This is the guts of the vi curses screen code.  The idea is that
152  *	screen.  What makes this hard is that we don't know how big
175 #define	SCNO	vip->sc_col		/* Current screen column. */  in vs_paint()
185 	 * fill in the map from scratch.  Adjust the screen that's being  in vs_paint()
210 	 * before, if the movement is large, the screen is repainted.  in vs_paint()
215 	 * the screen artificially small.  The behavior of these options  in vs_paint()
217 	 * was never documented how various screen movements affected the  in vs_paint()
218 	 * screen size.  Generally, one of three things would happen:  in vs_paint()
219 	 *	1: The screen would expand in size, showing the line  in vs_paint()
220 	 *	2: The screen would scroll, showing the line  in vs_paint()
221 	 *	3: The screen would compress to its smallest size and  in vs_paint()
225 	 * was 1 line below the screen caused a screen compress), and cursor  in vs_paint()
231 	 * a full screen away.  If it is, we expand the screen if there's  in vs_paint()
241 	 * screen but the column offset is not, we'll end up in the adjust  in vs_paint()
242 	 * code, when we should probably have compressed the screen.  in vs_paint()
284 	 * 6b: Line down, or current screen.  in vs_paint()
287 		/* Current screen. */  in vs_paint()
296 		 * If less than half a screen above the line, scroll down  in vs_paint()
297 		 * until the line is on the screen.  in vs_paint()
310 	 * 6c: If not on the current screen, may request center or top.  in vs_paint()
323 		 * If less than half a screen below the line, scroll up until  in vs_paint()
324 		 * the line is the first line on the screen.  Special check so  in vs_paint()
325 		 * that if the screen has been emptied, we refill it.  in vs_paint()
336 		 * If less than a half screen from the bottom of the file,  in vs_paint()
337 		 * put the last line of the file on the bottom of the screen.  in vs_paint()
356 	 * If less than half a screen from the top of the file, put the first  in vs_paint()
357 	 * line of the file at the top of the screen.  Otherwise, put the line  in vs_paint()
358 	 * in the middle of the screen.  in vs_paint()
377 	 * At this point we know part of the line is on the screen.  Since  in vs_paint()
379 	 * line may not be on the screen.  While that's not necessarily bad,  in vs_paint()
381 	 * This can be tricky; if the line covers the entire screen, lno  in vs_paint()
389 	 * going to be a serious problem, refill the screen and repaint.  in vs_paint()
417 	 * If the screen needs to be repainted, skip cursor optimization.  in vs_paint()
420 	 * the right screen is up.  in vs_paint()
429 	 * 7: Cursor movements (current screen only).  in vs_paint()
479 	 * screen, and therefore, how many screen positions to move.  in vs_paint()
497 		 * we cross a screen boundary as we do in the cursor right  in vs_paint()
513 		 * Decrement the screen cursor by the total width of the  in vs_paint()
528 		 * moved off of the current screen, as well.  in vs_paint()
545 		 * screen boundary, we can quit.  in vs_paint()
555 		 * Increment the screen cursor by the total width of the  in vs_paint()
560 		/* See screen change comment in section 6a. */  in vs_paint()
584 	 * the displayed screen, scroll the screen left or right, unless we're  in vs_paint()
588 	 * first screen as compared to subsequent ones.  in vs_paint()
592 		 * Get the screen column for this character, and correct  in vs_paint()
620 shifted:		/* Fill in screen map with the new offset. */  in vs_paint()
632 		 * We may have jumped here to adjust a leftright screen because  in vs_paint()
633 		 * redraw was set.  If so, we have to paint the entire screen.  in vs_paint()
640 	 * Update the screen lines for this particular file line until we  in vs_paint()
641 	 * have a new screen cursor position.  in vs_paint()
655 	 * 8: Repaint the entire screen.  in vs_paint()
658 	 * SC_SCR_REDRAW gets set when the screen isn't worth fixing, and  in vs_paint()
671 	 * If it's a small screen and we're redrawing, clear the unused lines,  in vs_paint()
708 	 * didn't repaint the screen, repaint all of the line numbers,  in vs_paint()
718 	 * If we warped the screen, we have to refresh everything.  in vs_paint()
732 		 * If the screen shifted, we recalculate the "most favorite"  in vs_paint()
734 		 * screen, so it's going to have a wrong idea about where the  in vs_paint()
791 	 * screen, SunOS 4.1.1 and Ultrix 4.2 curses won't let you.  in vs_modeline()
793 	 * Move to the last line on the screen.  in vs_modeline()
797 	/* If more than one screen in the display, show the file name. */  in vs_modeline()
845 	 * column on the screen.  in vs_modeline()