[sixel] call sprite_sixel_init at proper time #1436

NEWS.md

@@ -6,6 +6,7 @@ rearrangements of Notcurses.
     Kitty pixel graphics protocol.
   * Added `notcurses_debug_caps()` to dump terminal properties, both those
     reported and those inferred, to a `FILE*`.
+  * Added `NCOPTION_NO_CLEAR_BITMAPS` option for `notcurses_init()`.
 
 * 2.2.3 (2021-03-08)
   * Implemented **EXPERIMENTAL** `NCBLIT_PIXEL` for terminals reporting Sixel

USAGE.md

@@ -91,6 +91,12 @@ typedef enum {
 // doing something weird (setting a locale not based on LANG).
 #define NCOPTION_INHIBIT_SETLOCALE   0x0001
 
+// We typically try to clear any preexisting bitmaps. If we ought *not* try
+// to do this, pass NCOPTION_NO_CLEAR_BITMAPS. Note that they might still
+// get cleared even if this is set, and they might not get cleared even if
+// this is not set. It's a tough world out there.
+#define NCOPTION_NO_CLEAR_BITMAPS    0x0002ull
+
 // We typically install a signal handler for SIGWINCH that generates a resize
 // event in the notcurses_getc() queue. Set to inhibit this handler.
 #define NCOPTION_NO_WINCH_SIGHANDLER 0x0004

doc/man/man3/notcurses_init.3.md

@@ -12,6 +12,7 @@ notcurses_init - initialize a notcurses instance
 
 ```c
 #define NCOPTION_INHIBIT_SETLOCALE   0x0001ull
+#define NCOPTION_NO_CLEAR_BITMAPS    0x0002ull
 #define NCOPTION_NO_WINCH_SIGHANDLER 0x0004ull
 #define NCOPTION_NO_QUIT_SIGHANDLERS 0x0008ull
 #define NCOPTION_SUPPRESS_BANNERS    0x0020ull
@@ -110,6 +111,10 @@ zero. The following flags are defined:
     the **LANG** environment variable. Your program should call **setlocale(3)**
     itself, usually as one of the first lines.
 
+* **NCOPTION_NO_CLEAR_BITMAPS**: On entry, make no special attempt to clear any
+    preexisting bitmaps. Note that they might still get cleared even if this is
+    set, and they might not get cleared even if this is not set.
+
 * **NCOPTION_NO_WINCH_SIGHANDLER**: A signal handler will usually be installed
     for **SIGWINCH** and **SIGCONT**, resulting in **NCKEY_RESIZE** events
     being generated on input. With this flag, the handler will not be

include/notcurses/notcurses.h

@@ -832,7 +832,11 @@ typedef enum {
 // doing something weird (setting a locale not based on LANG).
 #define NCOPTION_INHIBIT_SETLOCALE   0x0001ull
 
-// NCOPTION_VERIFY_PIXEL was removed in 2.2.3. It ought be repurposed. FIXME.
+// We typically try to clear any preexisting bitmaps. If we ought *not* try
+// to do this, pass NCOPTION_NO_CLEAR_BITMAPS. Note that they might still
+// get cleared even if this is set, and they might not get cleared even if
+// this is not set. It's a tough world out there.
+#define NCOPTION_NO_CLEAR_BITMAPS    0x0002ull
 
 // We typically install a signal handler for SIGWINCH that generates a resize
 // event in the notcurses_getc() queue. Set to inhibit this handler.

src/fetch/main.c

@@ -393,7 +393,7 @@ place_infoplane(struct ncdirect* ncd, int planeheight){
   }
   struct notcurses_options opts = {
     .flags = NCOPTION_SUPPRESS_BANNERS | NCOPTION_INHIBIT_SETLOCALE
-              | NCOPTION_NO_ALTERNATE_SCREEN,
+              | NCOPTION_NO_ALTERNATE_SCREEN | NCOPTION_NO_CLEAR_BITMAPS,
     .margin_t = cury,
     .margin_b = dimy - (cury + planeheight),
   };

src/lib/internal.h

@@ -321,7 +321,7 @@ 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);
-  int (*pixel_init)(const struct notcurses* nc);
+  int (*pixel_init)(int fd);
   bool pixel_query_done; // have we yet performed pixel query?
   bool sextants;  // do we have (good, vetted) Unicode 13 sextant support?
   bool braille;   // do we have Braille support? (linux console does not)
@@ -730,8 +730,8 @@ sprixel* sprixel_create(ncplane* n, const char* s, int bytes, int placey, int pl
                         int parse_start);
 API int sprite_wipe_cell(const notcurses* nc, sprixel* s, int y, int x);
 int sprite_kitty_annihilate(const notcurses* nc, const ncpile* p, FILE* out, sprixel* s);
-int sprite_kitty_init(const notcurses* nc);
-int sprite_sixel_init(const notcurses* nc);
+int sprite_kitty_init(int fd);
+int sprite_sixel_init(int fd);
 int sprite_sixel_annihilate(const notcurses* nc, const ncpile* p, FILE* out, sprixel* s);
 int sprite_init(const notcurses* nc);
 

src/lib/kitty.c

@@ -285,6 +285,6 @@ int kitty_blit(ncplane* nc, int linesize, const void* data,
   return r;
 }
 
-int sprite_kitty_init(const notcurses* nc){
-  return tty_emit("\e_Ga=d\e\\", nc->ttyfd);
+int sprite_kitty_init(int fd){
+  return tty_emit("\e_Ga=d\e\\", fd);
 }

src/lib/notcurses.c

@@ -1037,9 +1037,11 @@ notcurses* notcurses_core_init(const notcurses_options* opts, FILE* outfp){
     goto err;
   }
   if(ret->ttyfd >= 0){
-    if(sprite_init(ret)){
-      free_plane(ret->stdplane);
-      goto err;
+    if(!(opts->flags & NCOPTION_NO_CLEAR_BITMAPS)){
+      if(sprite_init(ret)){
+        free_plane(ret->stdplane);
+        goto err;
+      }
     }
     if(ret->tcache.smkx && tty_emit(ret->tcache.smkx, ret->ttyfd)){
       free_plane(ret->stdplane);

src/lib/sixel.c

@@ -551,9 +551,9 @@ int sixel_blit(ncplane* nc, int linesize, const void* data,
   return r;
 }
 
-int sprite_sixel_init(const notcurses* nc){
+int sprite_sixel_init(int fd){
   // \e[?8452: DECSDM private "sixel scrolling" mode keeps the sixel from
   // scrolling, but puts it at the current cursor location (as opposed to
   // the upper left corner of the screen).
-  return tty_emit("\e[?8452h", nc->ttyfd);
+  return tty_emit("\e[?8452h", fd);
 }

src/lib/sprite.c

@@ -77,5 +77,5 @@ int sprite_init(const notcurses* nc){
   if(!nc->tcache.pixel_init){
     return 0;
   }
-  return nc->tcache.pixel_init(nc);
+  return nc->tcache.pixel_init(nc->ttyfd);
 }

src/lib/terminfo.c

@@ -384,6 +384,7 @@ int query_term(tinfo* ti, int fd){
     if(ti->sixel_supported){
       query_sixel_details(ti, fd);
     }
+    ti->pixel_init(fd);
     if(flags & O_NONBLOCK){
       fcntl(fd, F_SETFL, flags);
     }