From 31508228bc26306a7fbf138c9df2e7210e9e5a37 Mon Sep 17 00:00:00 2001
From: Nicholas Marriott <nicholas.marriott@gmail.com>
Date: Mon, 20 Aug 2018 19:34:04 +0100
Subject: [PATCH] Use the y offset from the context which has already been
 adjusted for the status line, also make tty_clamp_line adjust the y position.

---
 screen-write.c |  8 +++++---
 tty.c          | 48 +++++++++++++++++++++++-------------------------
 2 files changed, 28 insertions(+), 28 deletions(-)

diff --git a/screen-write.c b/screen-write.c
index b9db16a9..4f5bee61 100644
--- a/screen-write.c
+++ b/screen-write.c
@@ -94,7 +94,7 @@ void
 screen_write_start(struct screen_write_ctx *ctx, struct window_pane *wp,
     struct screen *s)
 {
-	char	tmp[16];
+	char	tmp[32];
 	u_int	y;
 
 	memset(ctx, 0, sizeof *ctx);
@@ -113,8 +113,10 @@ screen_write_start(struct screen_write_ctx *ctx, struct window_pane *wp,
 	ctx->scrolled = 0;
 	ctx->bg = 8;
 
-	if (wp != NULL)
-		snprintf(tmp, sizeof tmp, "pane %%%u", wp->id);
+	if (wp != NULL) {
+		snprintf(tmp, sizeof tmp, "pane %%%u (at %u,%u)", wp->id,
+		    wp->xoff, wp->yoff);
+	}
 	log_debug("%s: size %ux%u, %s", __func__, screen_size_x(ctx->s),
 	    screen_size_y(ctx->s), wp == NULL ? "no pane" : tmp);
 }
diff --git a/tty.c b/tty.c
index b6339266..6e7ccafe 100644
--- a/tty.c
+++ b/tty.c
@@ -889,13 +889,12 @@ static int
 tty_is_visible(const struct tty_ctx *ctx, u_int px, u_int py, u_int nx,
     u_int ny)
 {
-	struct window_pane	*wp = ctx->wp;
-	u_int			 xoff = wp->xoff + px, yoff = wp->yoff + py;
+	u_int	xoff = ctx->xoff + px, yoff = ctx->yoff + py;
 
 	if (!ctx->bigger)
 		return (1);
-	if (xoff + nx <= ctx->ox || xoff >= ctx->ox + ctx->sx ||
-	    yoff + ny <= ctx->oy || yoff >= ctx->oy + ctx->sy) {
+	if (xoff + nx <= ctx->ox || xoff > ctx->ox + ctx->sx ||
+	    yoff + ny <= ctx->oy || yoff > ctx->oy + ctx->sy) {
 		return (0);
 	}
 	return (1);
@@ -904,13 +903,13 @@ tty_is_visible(const struct tty_ctx *ctx, u_int px, u_int py, u_int nx,
 /* Clamp line position to visible part of pane. */
 static int
 tty_clamp_line(const struct tty_ctx *ctx, u_int px, u_int py, u_int nx,
-    u_int *i, u_int *x, u_int *rx)
+    u_int *i, u_int *x, u_int *rx, u_int *ry)
 {
-	struct window_pane	*wp = ctx->wp;
-	u_int			 xoff = wp->xoff + px;
+	u_int	xoff = ctx->xoff + px;
 
 	if (!tty_is_visible(ctx, px, py, nx, 1))
 		return (0);
+	*ry = ctx->yoff + py - ctx->oy;
 
 	if (xoff >= ctx->ox && xoff + nx <= ctx->ox + ctx->sx) {
 		/* All visible. */
@@ -983,10 +982,13 @@ static void
 tty_clear_pane_line(struct tty *tty, const struct tty_ctx *ctx, u_int py,
     u_int px, u_int nx, u_int bg)
 {
-	u_int	i, x, rx;
+	struct client	*c = tty->client;
+	u_int		 i, x, rx, ry;
 
-	if (tty_clamp_line(ctx, px, py, nx, &i, &x, &rx))
-		tty_clear_line(tty, ctx->wp, py - ctx->oy, x, rx, bg);
+	log_debug("%s: %s, %u at %u,%u", __func__, c->name, nx, px, py);
+
+	if (tty_clamp_line(ctx, px, py, nx, &i, &x, &rx, &ry))
+		tty_clear_line(tty, ctx->wp, ry, x, rx, bg);
 }
 
 /* Clamp area position to visible part of pane. */
@@ -994,11 +996,9 @@ static int
 tty_clamp_area(const struct tty_ctx *ctx, u_int px, u_int py, u_int nx,
     u_int ny, u_int *i, u_int *j, u_int *x, u_int *y, u_int *rx, u_int *ry)
 {
-	struct window_pane	*wp = ctx->wp;
-	u_int			 xoff = wp->xoff + px, yoff = wp->yoff + py;
+	u_int	xoff = ctx->xoff + px, yoff = ctx->yoff + py;
 
-	if (xoff + nx <= ctx->ox || xoff >= ctx->ox + ctx->sx ||
-	    yoff + ny <= ctx->oy || yoff >= ctx->oy + ctx->sy)
+	if (!tty_is_visible(ctx, px, py, nx, ny))
 		return (0);
 
 	if (xoff >= ctx->ox && xoff + nx <= ctx->ox + ctx->sx) {
@@ -1134,17 +1134,16 @@ tty_draw_pane(struct tty *tty, const struct tty_ctx *ctx, u_int py)
 {
 	struct window_pane	*wp = ctx->wp;
 	struct screen		*s = wp->screen;
-	u_int			 xoff = ctx->xoff, yoff = ctx->yoff;
-	u_int			 nx = screen_size_x(s), i, x, rx;
+	u_int			 nx = screen_size_x(s), i, x, rx, ry;
 
 	log_debug("%s: %s %u %d", __func__, tty->client->name, py, ctx->bigger);
 
 	if (!ctx->bigger) {
-		tty_draw_line(tty, wp, s, 0, py, nx, xoff, yoff + py);
+		tty_draw_line(tty, wp, s, 0, py, nx, ctx->xoff, ctx->yoff);
 		return;
 	}
-	if (tty_clamp_line(ctx, 0, py, nx, &i, &x, &rx))
-		tty_draw_line(tty, wp, s, i, py, rx, x, yoff + py - ctx->oy);
+	if (tty_clamp_line(ctx, 0, py, nx, &i, &x, &rx, &ry))
+		tty_draw_line(tty, wp, s, i, py, rx, x, ry);
 }
 
 static const struct grid_cell *
@@ -1465,35 +1464,34 @@ void
 tty_cmd_clearline(struct tty *tty, const struct tty_ctx *ctx)
 {
 	struct window_pane	*wp = ctx->wp;
-	u_int			 nx, py = ctx->yoff + ctx->ocy;
+	u_int			 nx;
 
 	tty_default_attributes(tty, wp, ctx->bg);
 
 	nx = screen_size_x(wp->screen);
-	tty_clear_pane_line(tty, ctx, py, 0, nx, ctx->bg);
+	tty_clear_pane_line(tty, ctx, ctx->ocy, 0, nx, ctx->bg);
 }
 
 void
 tty_cmd_clearendofline(struct tty *tty, const struct tty_ctx *ctx)
 {
 	struct window_pane	*wp = ctx->wp;
-	u_int			 nx, py = ctx->yoff + ctx->ocy;
+	u_int			 nx;
 
 	tty_default_attributes(tty, wp, ctx->bg);
 
 	nx = screen_size_x(wp->screen) - ctx->ocx;
-	tty_clear_pane_line(tty, ctx, py, ctx->ocx, nx, ctx->bg);
+	tty_clear_pane_line(tty, ctx, ctx->ocy, ctx->ocx, nx, ctx->bg);
 }
 
 void
 tty_cmd_clearstartofline(struct tty *tty, const struct tty_ctx *ctx)
 {
 	struct window_pane	*wp = ctx->wp;
-	u_int			 py = ctx->yoff + ctx->ocy;
 
 	tty_default_attributes(tty, wp, ctx->bg);
 
-	tty_clear_pane_line(tty, ctx, py, 0, ctx->ocx + 1, ctx->bg);
+	tty_clear_pane_line(tty, ctx, ctx->ocy, 0, ctx->ocx + 1, ctx->bg);
 }
 
 void