From 3e0783593d715364748197f9d78333b2fb1695a3 Mon Sep 17 00:00:00 2001
From: nick black <dankamongmen@gmail.com>
Date: Sat, 24 Apr 2021 22:44:56 -0400
Subject: [PATCH] add sprixel_rebuild interface, kitty + sixel skeletons #1440

---
 src/lib/internal.h | 11 ++++++++++-
 src/lib/kitty.c    |  8 ++++++++
 src/lib/render.c   |  3 +--
 src/lib/sixel.c    |  8 ++++++++
 src/lib/terminfo.c |  2 ++
 5 files changed, 29 insertions(+), 3 deletions(-)

diff --git a/src/lib/internal.h b/src/lib/internal.h
index ed47ea867..13ab65a2f 100644
--- a/src/lib/internal.h
+++ b/src/lib/internal.h
@@ -450,6 +450,8 @@ typedef struct tinfo {
   // means leaving out the pixels (and likely resizes the string). for kitty,
   // this means dialing down their alpha to 0 (in equivalent space).
   int (*pixel_cell_wipe)(const struct notcurses* nc, sprixel* s, int y, int x);
+  // perform the inverse of pixel_cell_wipe, restoring an annihilated sprixcell.
+  int (*pixel_rebuild)(const struct notcurses* nc, sprixel* s, int y, int x);
   int (*pixel_remove)(int id, FILE* out); // kitty only, issue actual delete command
   int (*pixel_init)(int fd);     // called when support is detected
   int (*pixel_draw)(const struct notcurses* n, const struct ncpile* p, sprixel* s, FILE* out);
@@ -922,7 +924,9 @@ int sixel_wipe(const notcurses* nc, sprixel* s, int ycell, int xcell);
 // nulls out a cell from a kitty bitmap via changing the alpha value
 // throughout to 0. the same trick doesn't work on sixel, but there we
 // can just print directly over the bitmap.
-int kitty_wipe(const notcurses* nc, sprixel* s, int y, int x);
+int kitty_wipe(const notcurses* nc, sprixel* s, int ycell, int xcell);
+int sixel_rebuild(const notcurses* nc, sprixel* s, int ycell, int xcell);
+int kitty_rebuild(const notcurses* nc, sprixel* s, int ycell, int xcell);
 
 void sprixel_free(sprixel* s);
 void sprixel_hide(sprixel* s);
@@ -960,6 +964,11 @@ sprite_destroy(const notcurses* nc, const ncpile* p, FILE* out, sprixel* s){
   return nc->tcache.pixel_destroy(nc, p, out, s);
 }
 
+static inline int
+sprite_rebuild(const notcurses* nc, sprixel* s, int ycell, int xcell){
+  return nc->tcache.pixel_rebuild(nc, s, ycell, xcell);
+}
+
 static inline void
 clamp_to_sixelmax(const tinfo* t, int* y, int* x){
   if(t->sixel_maxy && *y > t->sixel_maxy){
diff --git a/src/lib/kitty.c b/src/lib/kitty.c
index 04c3cd884..39ad48c5d 100644
--- a/src/lib/kitty.c
+++ b/src/lib/kitty.c
@@ -153,6 +153,14 @@ kitty_null(char* triplet, int skip, int max, int pleft){
 }
 
 #define RGBA_MAXLEN 768 // 768 base64-encoded pixels in 4096 bytes
+int kitty_rebuild(const notcurses* nc, sprixel* s, int ycell, int xcell){
+  (void)nc;
+  (void)s;
+  (void)ycell;
+  (void)xcell;
+  return 0;
+}
+
 int kitty_wipe(const notcurses* nc, sprixel* s, int ycell, int xcell){
   if(s->n->tacache[s->dimx * ycell + xcell] == SPRIXCELL_ANNIHILATED){
 //fprintf(stderr, "CACHED WIPE %d %d/%d\n", s->id, ycell, xcell);
diff --git a/src/lib/render.c b/src/lib/render.c
index e2bebbb61..72893a87a 100644
--- a/src/lib/render.c
+++ b/src/lib/render.c
@@ -178,8 +178,7 @@ paint_sprixel(ncplane* p, struct crender* rvec, int starty, int startx,
           crender->sprixel = s;
         }
         if(sprixel_state(s, absy, absx) == SPRIXCELL_ANNIHILATED){
-          // FIXME rebuild!
-fprintf(stderr, "annihilation UNDONE at %d/%d\n", y, x);
+          sprite_rebuild(nc, s, y, x);
         }
       }
     }
diff --git a/src/lib/sixel.c b/src/lib/sixel.c
index bbf2e18e5..49182d459 100644
--- a/src/lib/sixel.c
+++ b/src/lib/sixel.c
@@ -746,6 +746,14 @@ int sixel_init(int fd){
   return tty_emit("\e[?80;8452h", fd);
 }
 
+int sixel_rebuild(const notcurses* nc, sprixel* s, int ycell, int xcell){
+  (void)nc;
+  (void)s;
+  (void)ycell;
+  (void)xcell;
+  return 0;
+}
+
 // we return -1 because we're not doing a proper wipe -- that's not possible
 // using sixel. we just mark it as partially transparent, so that if it's
 // redrawn, it's redrawn using P2=1.
diff --git a/src/lib/terminfo.c b/src/lib/terminfo.c
index 15f490473..159b30d00 100644
--- a/src/lib/terminfo.c
+++ b/src/lib/terminfo.c
@@ -15,6 +15,7 @@ setup_sixel_bitmaps(tinfo* ti){
   ti->pixel_destroy = sixel_destroy;
   ti->pixel_cell_wipe = sixel_wipe;
   ti->pixel_shutdown = sixel_shutdown;
+  ti->pixel_rebuild = sixel_rebuild;
   ti->sprixel_height_factor = 6;
 }
 
@@ -27,6 +28,7 @@ setup_kitty_bitmaps(tinfo* ti){
   ti->pixel_draw = kitty_draw;
   ti->pixel_shutdown = kitty_shutdown;
   ti->sprixel_height_factor = 1;
+  ti->pixel_rebuild = kitty_rebuild;
   set_pixel_blitter(kitty_blit);
 }