Redo screen.c functions to make them readable and more flexible. Make scroll mode only redraw waht it needs.

CHANGES

@@ -1,5 +1,9 @@
 21 November 2007
 
+* Redo screen redrawing so it is a) readable b) split into utility functions
+  that can be used outside screen.c. Use these to make scroll mode only
+  redraw what it has to which gets rid of irritating flickering status box and
+  makes it much faster.
 * Full line width memory and horizontal scrolling in history.
 * Initial support for scroll history. = to enter scrolling mode, and then
   vi keys or up/down/pgup/pgdown to navigate. Q to exit. No horizontal history
@@ -241,4 +245,4 @@
   (including mutt, emacs). No status bar yet and no key remapping or other
   customisation.
 
-$Id: CHANGES,v 1.77 2007-11-21 15:35:53 nicm Exp $
+$Id: CHANGES,v 1.78 2007-11-21 18:24:49 nicm Exp $

TODO

@@ -72,8 +72,6 @@
 - there is to much redrawing. use flags? (there was a problem with this idea...
   CLIENT_HOLD?)
 - use modes for help etc
-- scrollback should only draw scrolled line on up/down
-- horizontal scrolling
 
 -- For 0.2 --------------------------------------------------------------------
 - copy and paste

screen.c

@@ -1,4 +1,4 @@
-/* $Id: screen.c,v 1.31 2007-11-21 15:35:53 nicm Exp $ */
+/* $Id: screen.c,v 1.32 2007-11-21 18:24:49 nicm Exp $ */
 
 /*
  * Copyright (c) 2007 Nicholas Marriott <nicm@users.sourceforge.net>
@@ -212,60 +212,159 @@ screen_destroy(struct screen *s)
 	xfree(s->grid_size);
 }
 
-/* Draw a set of lines on the screen. */
+/* Initialise drawing. */
 void
-screen_draw(
+screen_draw_start(struct screen_draw_ctx *ctx,
-    struct screen *s, struct buffer *b, u_int py, u_int ny, u_int ox, u_int oy)
+    struct screen *s, struct buffer *b, u_int ox, u_int oy)
 {
-	u_char	 attr, colr;
+	ctx->s = s;
-	u_int	 i, j, nx, base;
+	ctx->b = b;
 
-	/* XXX. This is naive and rough right now. */
+	ctx->ox = ox;
-	attr = 0;
+	ctx->oy = oy;
-	colr = SCREEN_DEFCOLR;
+
+	ctx->cx = s->cx;
+	ctx->cy = s->cy;
+
+	ctx->attr = s->attr;
+	ctx->colr = s->colr;
+
+	input_store_two(b, CODE_SCROLLREGION, 1, screen_size_y(s));
+
+	if (s->mode & MODE_CURSOR)
+		input_store_zero(b, CODE_CURSOROFF);
+}
+
+/* Finalise drawing. */
+void
+screen_draw_stop(struct screen_draw_ctx *ctx)
+{
+	struct screen	*s = ctx->s;
+	struct buffer	*b = ctx->b;
 
 	input_store_two(b, CODE_SCROLLREGION, s->rupper + 1, s->rlower + 1);
 
-	input_store_zero(b, CODE_CURSOROFF);
+	if (ctx->cx != s->cx || ctx->cy != s->cy)
-	input_store_two(b, CODE_ATTRIBUTES, attr, colr);
+		input_store_two(b, CODE_CURSORMOVE, s->cy + 1, s->cx + 1);
 
-	base = screen_y(s, 0);
+	if (ctx->attr != s->attr || ctx->colr != s->colr)
-	if (oy > base)
+		input_store_two(b, CODE_ATTRIBUTES, s->attr, s->colr);
-		base = 0;
-	else
-		base -= oy;
 	
-	for (j = py; j < py + ny; j++) {
-		input_store_two(b, CODE_CURSORMOVE, j + 1, 1);
-
-		nx = s->grid_size[base + j] - ox;
-		if (nx > screen_size_x(s))
-			nx = screen_size_x(s);
-		for (i = 0; i < nx; i++) {
-			if (s->grid_attr[base + j][ox + i] != attr ||
-			    s->grid_colr[base + j][ox + i] != colr) {
-				input_store_two(b, CODE_ATTRIBUTES,
-				    s->grid_attr[base + j][ox + i],
-				    s->grid_colr[base + j][ox + i]);
-				attr = s->grid_attr[base + j][ox + i];
-				colr = s->grid_colr[base + j][ox + i];
-			}
-			input_store8(b, s->grid_data[base + j][ox + i]);
-		}
-		if (nx != screen_size_x(s)) {
-			input_store_two(
-			    b, CODE_ATTRIBUTES, SCREEN_DEFATTR, SCREEN_DEFCOLR);
-			for (i = nx; i < screen_size_x(s); i++)
-				input_store8(b, SCREEN_DEFDATA);
-		}
- 	}
-	input_store_two(b, CODE_CURSORMOVE, s->cy + 1, s->cx + 1);
-
-	input_store_two(b, CODE_ATTRIBUTES, s->attr, s->colr);
 	if (s->mode & MODE_CURSOR)
 		input_store_zero(b, CODE_CURSORON);
 }
 
+/* Get cell data. */
+void
+screen_draw_get_cell(struct screen_draw_ctx *ctx,
+    u_int px, u_int py, u_char *data, u_char *attr, u_char *colr)
+{
+	struct screen	*s = ctx->s;
+	u_int		 cx, cy;
+	
+	cx = ctx->ox + px;
+	cy = screen_y(s, py) - ctx->oy;
+
+	if (cx >= s->grid_size[cy]) {
+		*data = SCREEN_DEFDATA;
+		*attr = SCREEN_DEFATTR;
+		*colr = SCREEN_DEFCOLR;
+	} else {
+		*data = s->grid_data[cy][cx];
+		*attr = s->grid_attr[cy][cx];
+		*colr = s->grid_colr[cy][cx];
+	}
+}
+
+/* Move cursor. */
+void
+screen_draw_move(struct screen_draw_ctx *ctx, u_int px, u_int py)
+{
+	if (px == ctx->cx && py == ctx->cy)
+		return;
+
+	input_store_two(ctx->b, CODE_CURSORMOVE, py + 1, px + 1);
+
+	ctx->cx = px;
+	ctx->cy = py;
+}
+
+/* Set attributes. */
+void
+screen_draw_set_attributes(
+    struct screen_draw_ctx *ctx, u_char attr, u_char colr)
+{
+	if (attr != ctx->attr || colr != ctx->colr) {
+		input_store_two(ctx->b, CODE_ATTRIBUTES, attr, colr);
+		ctx->attr = attr;
+		ctx->colr = colr;
+	}
+}
+
+/* Draw single cell. */
+void
+screen_draw_cell(struct screen_draw_ctx *ctx, u_int px, u_int py)
+{
+	struct buffer	*b = ctx->b;
+	u_char		 data, attr, colr;
+
+	screen_draw_move(ctx, px, py);
+
+	screen_draw_get_cell(ctx, px, py, &data, &attr, &colr);
+	screen_draw_set_attributes(ctx, attr, colr);
+	input_store8(b, data);
+
+	/*
+	 * Don't try to wrap as it will cause problems when screen is smaller
+	 * than client.
+	 */
+	ctx->cx++;
+}
+
+/* Draw range of cells. */
+void
+screen_draw_cells(struct screen_draw_ctx *ctx, u_int px, u_int py, u_int nx)
+{
+	u_int	i;
+
+	for (i = px; i < px + nx; i++)
+		screen_draw_cell(ctx, i, py);
+}
+
+/* Draw single column. */
+void
+screen_draw_column(struct screen_draw_ctx *ctx, u_int px)
+{
+	u_int	i;
+
+	for (i = 0; i < screen_size_y(ctx->s); i++)
+		screen_draw_cell(ctx, px, i);
+}
+
+/* Draw single line. */
+void
+screen_draw_line(struct screen_draw_ctx *ctx, u_int py)
+{
+	screen_draw_cells(ctx, 0, py, screen_size_x(ctx->s));
+}
+
+/* Draw set of lines. */
+void
+screen_draw_lines(struct screen_draw_ctx *ctx, u_int py, u_int ny)
+{
+	u_int		 i;
+
+	for (i = py; i < py + ny; i++)
+		screen_draw_line(ctx, i);
+}
+
+/* Draw entire screen. */
+void
+screen_draw_screen(struct screen_draw_ctx *ctx)
+{
+	screen_draw_lines(ctx, 0, screen_size_y(ctx->s));
+}
+
 /* Create a range of lines. */
 void
 screen_make_lines(struct screen *s, u_int py, u_int ny)

tmux.h

@@ -1,4 +1,4 @@
-/* $Id: tmux.h,v 1.87 2007-11-21 15:35:53 nicm Exp $ */
+/* $Id: tmux.h,v 1.88 2007-11-21 18:24:49 nicm Exp $ */
 
 /*
  * Copyright (c) 2007 Nicholas Marriott <nicm@users.sourceforge.net>
@@ -378,6 +378,21 @@ struct screen {
 	int		 mode;
 };
 
+/* Screen redraw context. */
+struct screen_draw_ctx {
+	struct screen	*s;
+	struct buffer	*b;
+
+	u_int		 cx;
+	u_int		 cy;
+
+	u_int		 ox;
+	u_int		 oy;
+
+	u_int		 attr;
+	u_int		 colr;
+};
+
 /* Screen display access macros. */
 #define screen_x(s, x) (x)
 #define screen_y(s, y) ((s)->hsize + y)
@@ -749,8 +764,19 @@ u_char	 screen_stringcolour(const char *);
 void	 screen_create(struct screen *, u_int, u_int);
 void	 screen_destroy(struct screen *);
 void	 screen_resize(struct screen *, u_int, u_int);
-void	 screen_draw(
+void	 screen_draw_start(struct screen_draw_ctx *,
-    	     struct screen *, struct buffer *, u_int, u_int, u_int, u_int);
+    	     struct screen *, struct buffer *, u_int, u_int);
+void	 screen_draw_stop(struct screen_draw_ctx *);
+void	 screen_draw_get_cell(struct screen_draw_ctx *,
+    	     u_int, u_int, u_char *, u_char *, u_char *);
+void	 screen_draw_move(struct screen_draw_ctx *, u_int, u_int);
+void	 screen_draw_set_attributes(struct screen_draw_ctx *, u_char, u_char);
+void	 screen_draw_cell(struct screen_draw_ctx *, u_int, u_int);
+void	 screen_draw_cells(struct screen_draw_ctx *, u_int, u_int, u_int);
+void	 screen_draw_column(struct screen_draw_ctx *, u_int);
+void	 screen_draw_line(struct screen_draw_ctx *, u_int);
+void	 screen_draw_lines(struct screen_draw_ctx *, u_int, u_int);
+void	 screen_draw_screen(struct screen_draw_ctx *);
 void	 screen_make_lines(struct screen *, u_int, u_int);
 void	 screen_free_lines(struct screen *, u_int, u_int);
 void	 screen_move_lines(struct screen *, u_int, u_int, u_int);

window-scroll.c

@@ -1,4 +1,4 @@
-/* $Id: window-scroll.c,v 1.6 2007-11-21 15:55:02 nicm Exp $ */
+/* $Id: window-scroll.c,v 1.7 2007-11-21 18:24:49 nicm Exp $ */
 
 /*
  * Copyright (c) 2007 Nicholas Marriott <nicm@users.sourceforge.net>
@@ -27,8 +27,12 @@ void	window_scroll_resize(struct window *, u_int, u_int);
 void	window_scroll_draw(struct window *, struct buffer *, u_int, u_int);
 void	window_scroll_key(struct window *, int);
 
+void	window_scroll_draw_position(struct window *, struct screen_draw_ctx *);
+
 void	window_scroll_up_1(struct window *);
 void	window_scroll_down_1(struct window *);
+void	window_scroll_left_1(struct window *);
+void	window_scroll_right_1(struct window *);
 
 const struct window_mode window_scroll_mode = {
 	window_scroll_init,
@@ -58,34 +62,52 @@ window_scroll_resize(unused struct window *w, unused u_int sx, unused u_int sy)
 {
 }
 
+void
+window_scroll_draw_position(struct window *w, struct screen_draw_ctx *ctx)
+{
+	struct window_scroll_mode_data	*data = w->modedata;
+	char				*ptr, buf[32];
+	size_t	 			 len;
+
+	len = xsnprintf(
+	    buf, sizeof buf, "[%u,%u/%u]", data->ox, data->oy, ctx->s->hsize);
+	if (len <= screen_size_x(ctx->s))
+		ptr = buf;
+	else {
+		ptr = buf + len - screen_size_x(ctx->s);
+		len -= len - screen_size_x(ctx->s);
+	}
+	
+	screen_draw_cells(ctx, 0, 0, screen_size_x(ctx->s) - len);
+	
+	screen_draw_move(ctx, screen_size_x(ctx->s) - len, 0);
+	screen_draw_set_attributes(ctx, 0, status_colour);
+	buffer_write(ctx->b, ptr, len);
+}
+
 void
 window_scroll_draw(struct window *w, struct buffer *b, u_int py, u_int ny)
 {
 	struct window_scroll_mode_data	*data = w->modedata;
 	struct screen			*s = &w->screen;
-	char    			 buf[32];
+	struct screen_draw_ctx		 ctx;
-	size_t		 		 len;
 
 	if (s->hsize != data->size) {
 		data->ox += s->hsize - data->size;
 		data->size = s->hsize;
 	}
 
-	screen_draw(s, b, py, ny, data->ox, data->oy);
+	screen_draw_start(&ctx, s, b, data->ox, data->oy);
+	if (py != 0)
+		screen_draw_lines(&ctx, py, ny);
+	else if (ny > 1)
+		screen_draw_lines(&ctx, py + 1, ny - 1);
+
+	if (py == 0)
+		window_scroll_draw_position(w, &ctx);
+
+	screen_draw_stop(&ctx);
 	input_store_zero(b, CODE_CURSOROFF);
-
-	if (py == 0 && ny > 0) {
-		len = screen_size_x(s);
-		if (len > (sizeof buf) - 1)
-			len = (sizeof buf) - 1;
-		len = xsnprintf(
-		    buf, len + 1, "[%u,%u/%u]", data->ox, data->oy, s->hsize);
-
-		input_store_two(
-		    b, CODE_CURSORMOVE, 0, screen_size_x(s) - len + 1);
-		input_store_two(b, CODE_ATTRIBUTES, 0, status_colour);
-		buffer_write(b, buf, len);
-	}
 }
 
 void
@@ -111,14 +133,12 @@ window_scroll_key(struct window *w, int key)
 		return;
 	case 'h':
 	case KEYC_LEFT:
-		if (data->ox > 0)
+		window_scroll_left_1(w);
-			data->ox--;
+		return;
-		break;
 	case 'l':
 	case KEYC_RIGHT:
-		if (data->ox < SHRT_MAX)
+		window_scroll_right_1(w);
-			data->ox++;
+		return;
-		break;
 	case 'k':
 	case 'K':
 	case KEYC_UP:
@@ -127,9 +147,8 @@ window_scroll_key(struct window *w, int key)
 	case 'j':
 	case 'J':
 	case KEYC_DOWN:
-		if (data->oy > 0)
+		window_scroll_down_1(w);
-			data->oy--;
+		return;
-		break;
 	case '\025':
 	case KEYC_PPAGE:
 		if (data->oy + sy > data->size)
@@ -154,6 +173,7 @@ window_scroll_up_1(struct window *w)
 {
 	struct window_scroll_mode_data	*data = w->modedata;
 	struct screen			*s = &w->screen;
+	struct screen_draw_ctx		 ctx;
 	struct client			*c;
 	u_int		 		 i;
 	struct hdr			 hdr;
@@ -174,11 +194,13 @@ window_scroll_up_1(struct window *w)
 		buffer_add(c->out, sizeof hdr);
 		size = BUFFER_USED(c->out);
 
-		input_store_two(c->out, CODE_CURSORMOVE, 1, screen_size_y(s));
+		screen_draw_start(&ctx, s, c->out, data->ox, data->oy);
+		screen_draw_move(&ctx, 0, 0);
 		input_store_one(c->out, CODE_INSERTLINE, 1);
-
+		window_scroll_draw_position(w, &ctx);
-		/* Redraw the top two lines to nuke the position display too. */
+		screen_draw_line(&ctx, 1);	/* nuke old position */
-		window_scroll_draw(w, c->out, 0, 2);
+		screen_draw_stop(&ctx);
+		input_store_zero(c->out, CODE_CURSOROFF);
 
 		size = BUFFER_USED(c->out) - size;
 		hdr.type = MSG_DATA;
@@ -192,6 +214,7 @@ window_scroll_down_1(struct window *w)
 {
 	struct window_scroll_mode_data	*data = w->modedata;
 	struct screen			*s = &w->screen;
+	struct screen_draw_ctx		 ctx;
 	struct client			*c;
 	u_int		 		 i;
 	struct hdr			 hdr;
@@ -212,11 +235,99 @@ window_scroll_down_1(struct window *w)
 		buffer_add(c->out, sizeof hdr);
 		size = BUFFER_USED(c->out);
 		
- 		input_store_two(c->out, CODE_CURSORMOVE, 1, 1);
+		screen_draw_start(&ctx, s, c->out, data->ox, data->oy);
+		screen_draw_move(&ctx, 0, 0);
 		input_store_one(c->out, CODE_DELETELINE, 1);
-
+		screen_draw_line(&ctx, screen_last_y(s));
- 		input_store_two(c->out, CODE_CURSORMOVE, 1, screen_size_y(s));
+		window_scroll_draw_position(w, &ctx);
-		window_scroll_draw(w, c->out, screen_last_y(s), 1);
+		screen_draw_stop(&ctx);
+		input_store_zero(c->out, CODE_CURSOROFF);
+		
+		size = BUFFER_USED(c->out) - size;
+		hdr.type = MSG_DATA;
+		hdr.size = size;
+		memcpy(BUFFER_IN(c->out) - size - sizeof hdr, &hdr, sizeof hdr);
+	}	
+}
+
+void
+window_scroll_right_1(struct window *w)
+{
+	struct window_scroll_mode_data	*data = w->modedata;
+	struct screen			*s = &w->screen;
+	struct screen_draw_ctx		 ctx;
+	struct client			*c;
+	u_int		 		 i, j;
+	struct hdr			 hdr;
+	size_t				 size;
+
+	if (data->ox >= SHRT_MAX)
+		return;
+	data->ox++;
+
+	for (i = 0; i < ARRAY_LENGTH(&clients); i++) {
+		c = ARRAY_ITEM(&clients, i);
+		if (c == NULL || c->session == NULL)
+			continue;
+		if (!session_has(c->session, w))
+			continue;
+
+		buffer_ensure(c->out, sizeof hdr);
+		buffer_add(c->out, sizeof hdr);
+		size = BUFFER_USED(c->out);
+		
+		screen_draw_start(&ctx, s, c->out, data->ox, data->oy);
+		for (j = 1; j < screen_size_y(s); j++) {
+			screen_draw_move(&ctx, 0, j);
+			input_store_one(c->out, CODE_DELETECHARACTER, 1);
+		}
+		screen_draw_column(&ctx, screen_last_x(s));
+		window_scroll_draw_position(w, &ctx);
+		screen_draw_stop(&ctx);
+		input_store_zero(c->out, CODE_CURSOROFF);
+		
+		size = BUFFER_USED(c->out) - size;
+		hdr.type = MSG_DATA;
+		hdr.size = size;
+		memcpy(BUFFER_IN(c->out) - size - sizeof hdr, &hdr, sizeof hdr);
+	}	
+}
+
+void
+window_scroll_left_1(struct window *w)
+{
+	struct window_scroll_mode_data	*data = w->modedata;
+	struct screen			*s = &w->screen;
+	struct screen_draw_ctx		 ctx;
+	struct client			*c;
+	u_int		 		 i, j;
+	struct hdr			 hdr;
+	size_t				 size;
+
+	if (data->ox == 0)
+		return;
+	data->ox--;
+
+	for (i = 0; i < ARRAY_LENGTH(&clients); i++) {
+		c = ARRAY_ITEM(&clients, i);
+		if (c == NULL || c->session == NULL)
+			continue;
+		if (!session_has(c->session, w))
+			continue;
+
+		buffer_ensure(c->out, sizeof hdr);
+		buffer_add(c->out, sizeof hdr);
+		size = BUFFER_USED(c->out);
+		
+		screen_draw_start(&ctx, s, c->out, data->ox, data->oy);
+		for (j = 1; j < screen_size_y(s); j++) {
+			screen_draw_move(&ctx, 0, j);
+			input_store_one(c->out, CODE_INSERTCHARACTER, 1);
+		}
+		screen_draw_column(&ctx, 0);
+		window_scroll_draw_position(w, &ctx);
+		screen_draw_stop(&ctx);
+		input_store_zero(c->out, CODE_CURSOROFF);
 		
 		size = BUFFER_USED(c->out) - size;
 		hdr.type = MSG_DATA;

window.c

@@ -1,4 +1,4 @@
-/* $Id: window.c,v 1.29 2007-11-21 15:35:53 nicm Exp $ */
+/* $Id: window.c,v 1.30 2007-11-21 18:24:49 nicm Exp $ */
 
 /*
  * Copyright (c) 2007 Nicholas Marriott <nicm@users.sourceforge.net>
@@ -284,10 +284,16 @@ window_parse(struct window *w, struct buffer *b)
 void
 window_draw(struct window *w, struct buffer *b, u_int py, u_int ny)
 {
+	struct screen		*s = &w->screen;
+	struct screen_draw_ctx	 ctx;
+
 	if (w->mode != NULL)
 		w->mode->draw(w, b, py, ny);
-	else
+	else {
-		screen_draw(&w->screen, b, py, ny, 0, 0);
+		screen_draw_start(&ctx, s, b, 0, 0);
+		screen_draw_lines(&ctx, py, ny);
+		screen_draw_stop(&ctx);
+	}
 }
 
 void