From c126f279e8489ee6f679f7eebb00f0fe405adef4 Mon Sep 17 00:00:00 2001
From: William McBrine <wmcbrine@gmail.com>
Date: Sun, 7 Jan 2018 14:22:16 -0500
Subject: [PATCH] Same for SDL1.

---
 sdl1/pdcdisp.c  | 30 +++++++++++++++++++++++++++++-
 sdl1/pdckbd.c   |  2 ++
 sdl1/pdcsdl.h   |  2 ++
 sdl1/pdcsetsc.c | 31 +++++++++++++++++++++++++++++--
 4 files changed, 62 insertions(+), 3 deletions(-)

diff --git a/sdl1/pdcdisp.c b/sdl1/pdcdisp.c
index 896af7be..f5a68ad8 100644
--- a/sdl1/pdcdisp.c
+++ b/sdl1/pdcdisp.c
@@ -72,6 +72,7 @@ static SDL_Rect uprect[MAXRECT];       /* table of rects to update */
 static chtype oldch = (chtype)(-1);    /* current attribute */
 static int rectcount = 0;              /* index into uprect */
 static short foregr = -2, backgr = -2; /* current foreground, background */
+static bool blinked_off = FALSE;
 
 /* do the real updates on a delay */
 
@@ -359,6 +360,9 @@ void PDC_transform_line(int lineno, int x, int len, const chtype *srcp)
 
         _set_attr(ch);
 
+        if (blinked_off && (ch & A_BLINK))
+            ch = (ch & A_ATTRIBUTES) | ' ';
+
 #ifdef CHTYPE_LONG
         if (ch & A_ALTCHARSET && !(ch & 0xff80))
             ch = (ch & (A_ATTRIBUTES ^ A_ALTCHARSET)) | acs_map[ch & 0x7f];
@@ -397,9 +401,33 @@ void PDC_transform_line(int lineno, int x, int len, const chtype *srcp)
         SDL_LowerBlit(pdc_font, &src, pdc_screen, &dest);
 #endif
 
-        if (ch & (A_UNDERLINE|A_LEFTLINE|A_RIGHTLINE))
+        if (!(blinked_off && (ch & A_BLINK)) &&
+            (ch & (A_UNDERLINE|A_LEFTLINE|A_RIGHTLINE)))
             _highlight(&src, &dest, ch);
 
         dest.x += pdc_fwidth;
     }
 }
+
+void PDC_blink_text(void)
+{
+    int i, j, k;
+
+    blinked_off = !blinked_off;
+
+    for (i = 0; i < SP->lines; i++)
+    {
+        const chtype *srcp = curscr->_y[i];
+
+        for (j = 0; j < SP->cols; j++)
+            if (srcp[j] & A_BLINK)
+            {
+                k = j;
+                while (k < SP->cols && (srcp[k] & A_BLINK))
+                    k++;
+                PDC_transform_line(i, j, k - j, srcp + j);
+                j = k;
+            }
+    }
+
+}
diff --git a/sdl1/pdckbd.c b/sdl1/pdckbd.c
index c598a4f3..f349f3df 100644
--- a/sdl1/pdckbd.c
+++ b/sdl1/pdckbd.c
@@ -382,6 +382,8 @@ int PDC_get_key(void)
     case SDL_KEYDOWN:
         PDC_mouse_set();
         return _process_key_event();
+    case SDL_USEREVENT:
+        PDC_blink_text();
     }
 
     return -1;
diff --git a/sdl1/pdcsdl.h b/sdl1/pdcsdl.h
index 4103405e..338902b6 100644
--- a/sdl1/pdcsdl.h
+++ b/sdl1/pdcsdl.h
@@ -29,3 +29,5 @@ extern Uint32 pdc_lastupdate;        /* time of last update, in ticks */
 
 PDCEX  void PDC_update_rects(void);
 PDCEX  void PDC_retile(void);
+
+extern void PDC_blink_text(void);
diff --git a/sdl1/pdcsetsc.c b/sdl1/pdcsetsc.c
index f05601d3..c93d8a40 100644
--- a/sdl1/pdcsetsc.c
+++ b/sdl1/pdcsetsc.c
@@ -59,13 +59,40 @@ void PDC_set_title(const char *title)
     SDL_WM_SetCaption(title, title);
 }
 
+static Uint32 _blink_timer(Uint32 interval, void *param)
+{
+    SDL_Event event;
+
+    event.type = SDL_USEREVENT;
+    SDL_PushEvent(&event);
+    return(interval);
+}
+
 int PDC_set_blink(bool blinkon)
 {
-    SP->termattrs &= ~A_BLINK;
+    static SDL_TimerID id;
+
     if (pdc_color_started)
         COLORS = 256;
 
-    return blinkon ? ERR : OK;
+    if (blinkon)
+    {
+        if (!(SP->termattrs & A_BLINK))
+        {
+            id = SDL_AddTimer(500, _blink_timer, NULL);
+            SP->termattrs |= A_BLINK;
+        }
+    }
+    else
+    {
+        if (SP->termattrs & A_BLINK)
+        {
+            SDL_RemoveTimer(id);
+            SP->termattrs &= ~A_BLINK;
+        }
+    }
+
+    return OK;
 }
 
 int PDC_set_bold(bool boldon)