ncvisual_from_sixel() atop ncsixel_as_rgba()

USAGE.md

@@ -3382,6 +3382,9 @@ struct ncvisual* ncvisual_from_bgra(struct notcurses* nc, const void* bgra,
 struct ncvisual* ncvisual_from_palidx(const void* data, int rows,
                                       int rowstride, int cols, int palsize,
                                       int pstride, const uint32_t* palette);
+
+// Construct an ncvisual from a nul-terminated Sixel control sequence.
+struct ncvisual* ncvisual_from_sixel(const char* s, unsigned leny, unsigned lenx);
 ```
 
 `ncvisual`s can also be loaded from the contents of a plane:
@@ -3635,9 +3638,6 @@ struct ncvisual* ncvisual_from_file(const char* file);
 // extract the next frame from an ncvisual. returns NCERR_EOF on end of file,
 // and NCERR_SUCCESS on success, otherwise some other NCERR.
 int ncvisual_decode(struct ncvisual* nc);
-
-// Convert a sixel escape into an RGBA vector.
-uint32_t* ncsixel_as_rgba(const char *s, unsigned leny, unsigned lenx);
 ```
 
 ### Pixels

doc/man/man3/notcurses_visual.3.md

@@ -121,7 +121,7 @@ typedef struct ncvgeom {
 
 **int ncplane_qrcode(struct ncplane* ***n***, unsigned* ***ymax***, unsigned* ***xmax***, const void* ***data***, size_t ***len***)**
 
-**uint32_t* ncsixel_as_rgba(const char* ***s***, unsigned ***leny***, unsigned ***lenx***);**
+**struct ncvisual* ncvisual_from_sixel(const char* ***s***, unsigned ***leny***, unsigned ***lenx***);**
 
 # DESCRIPTION
 

include/notcurses/notcurses.h

@@ -3153,6 +3153,10 @@ API ALLOC struct ncvisual* ncvisual_from_plane(const struct ncplane* n,
                                                unsigned leny, unsigned lenx)
   __attribute__ ((nonnull (1)));
 
+// Construct an ncvisual from a nul-terminated Sixel control sequence.
+API ALLOC struct ncvisual* ncvisual_from_sixel(const char* s, unsigned leny, unsigned lenx)
+  __attribute__ ((nonnull (1)));
+
 #define NCVISUAL_OPTION_NODEGRADE     0x0001ull // fail rather than degrade
 #define NCVISUAL_OPTION_BLEND         0x0002ull // use NCALPHA_BLEND with visual
 #define NCVISUAL_OPTION_HORALIGNED    0x0004ull // x is an alignment, not absolute
@@ -4492,10 +4496,6 @@ API ALLOC char* notcurses_hostname(void);
 // Returns a heap-allocated copy of human-readable OS name and version.
 API ALLOC char* notcurses_osversion(void);
 
-// Convert a sixel escape into an RGBA vector.
-API ALLOC uint32_t* ncsixel_as_rgba(const char *s, unsigned leny, unsigned lenx)
-  __attribute__ ((nonnull (1)));
-
 // Dump selected Notcurses state to the supplied 'debugfp'. Output is freeform,
 // newline-delimited, and subject to change. It includes geometry of all
 // planes, from all piles. No line has more than 80 columns' worth of output.

src/lib/sixel.c

@@ -1125,153 +1125,3 @@ uint8_t* sixel_trans_auxvec(const ncpile* p){
   }
   return a;
 }
-
-uint32_t* ncsixel_as_rgba(const char *sx, unsigned leny, unsigned lenx){
-#define MAXCOLORS 65535
-  uint32_t* rgba = malloc(sizeof(*rgba) * leny * lenx);
-  if(rgba == NULL){
-    return NULL;
-  }
-  uint32_t* colors = malloc(sizeof(*colors) * MAXCOLORS);
-  if(colors == NULL){
-    free(rgba);
-    return NULL;
-  }
-  // first we skip the header
-  while(*sx != '#'){
-    ++sx;
-  }
-  // now we build the color table (form: #Pc;Pu;Px;Py;Pz). data starts with
-  // a color spec lacking a semicolon.
-  enum {
-    STATE_WANT_HASH,
-    STATE_WANT_COLOR,
-    STATE_WANT_COLORSEMI,
-    STATE_WANT_COLORSPACE,
-    STATE_WANT_DATA,
-  } state = STATE_WANT_HASH;
-  unsigned color = 0;
-  unsigned x = 0;
-  unsigned y = 0;
-  unsigned rle = 1;
-  while(*sx){
-    if(*sx == '\e'){
-      break;
-    }
-    if(state == STATE_WANT_HASH){
-      if('#' != *sx){
-        goto err;
-      }
-      state = STATE_WANT_COLOR;
-    }else if(state == STATE_WANT_COLOR){
-      if(!isdigit(*sx)){
-        goto err;
-      }
-      color = 0;
-      do{
-        color *= 10;
-        color += *sx - '0';
-        ++sx;
-      }while(isdigit(*sx));
-//std::cerr << "Got color " << color << std::endl;
-      --sx;
-      state = STATE_WANT_COLORSEMI;
-    }else if(state == STATE_WANT_COLORSEMI){
-      // if we get a semicolon, we're a colorspec, otherwise data
-      if(*sx == ';'){
-        state = STATE_WANT_COLORSPACE;
-      }else{
-        state = STATE_WANT_DATA;
-        rle = 1;
-      }
-    }else if(state == STATE_WANT_COLORSPACE){
-      if('2' != *(sx++)){
-        goto err;
-      }
-      if(';' != *(sx++)){
-        goto err;
-      }
-      int r = 0;
-      do{
-        r *= 10;
-        r += *sx - '0';
-        ++sx;
-      }while(isdigit(*sx));
-      if(';' != *(sx++)){
-        goto err;
-      }
-      int g = 0;
-      do{
-        g *= 10;
-        g += *sx - '0';
-        ++sx;
-      }while(isdigit(*sx));
-      if(';' != *(sx++)){
-        goto err;
-      }
-      int b = 0;
-      do{
-        b *= 10;
-        b += *sx - '0';
-        ++sx;
-      }while(isdigit(*sx));
-      uint32_t rgb = htole(0xff000000 + (r << 16u) * 255 / 100 + (g << 8u) * 255 / 100 + b * 255 / 100);
-//std::cerr << "Got color " << color << ": " << r << "/" << g << "/" << b << std::endl;
-      if(color >= MAXCOLORS){
-        goto err;
-      }
-      colors[color] = rgb;
-      state = STATE_WANT_HASH;
-      --sx;
-    }
-    // read until we hit next colorspec
-    if(state == STATE_WANT_DATA){
-//std::cerr << "Character " << *sx << std::endl;
-      if(*sx == '#'){
-        state = STATE_WANT_HASH;
-        --sx;
-      }else if(*sx == '!'){ // RLE
-        ++sx;
-        rle = 0;
-        do{
-          rle *= 10;
-          rle += *sx - '0';
-          ++sx;
-        }while(isdigit(*sx));
-        if(2 >= rle){
-          goto err;
-        }
-        --sx;
-      }else if(*sx == '$'){
-        x = 0;
-        state = STATE_WANT_HASH;
-      }else if(*sx == '-'){
-        x = 0;
-        y += 6;
-        state = STATE_WANT_HASH;
-      }else{
-//std::cerr << "RLE: " << rle << " pos: " << y << "*" << x << std::endl;
-        for(unsigned xpos = x ; xpos < x + rle ; ++xpos){
-          for(unsigned ypos = y ; ypos < y + 6 ; ++ypos){
-            if((*sx - 63) & (1u << (ypos - y))){
-              // ought be an empty pixel
-//std::cerr << *s << " BMAP[" << ypos << "][" << xpos << "] = " << std::hex << colors[color] << std::dec << std::endl;
-              rgba[ypos * lenx + xpos] = colors[color];
-            }
-          }
-        }
-        x += rle;
-        rle = 1;
-      }
-    }
-    ++sx;
-  }
-  free(colors);
-  return rgba;
-
-err:
-  free(rgba);
-  free(colors);
-  return NULL;
-#undef MAXCOLORS
-}

src/lib/sixel.h

@@ -0,0 +1,167 @@
+#ifndef NOTCURSES_SIXEL
+#define NOTCURSES_SIXEL
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+#include <ctype.h>
+#include <stdlib.h>
+
+uint32_t* ncsixel_as_rgba(const char *sx, unsigned leny, unsigned lenx){
+#define MAXCOLORS 65535
+  // cast is necessary for c++ callers
+  uint32_t* rgba = (typeof rgba)malloc(sizeof(*rgba) * leny * lenx);
+  if(rgba == NULL){
+    return NULL;
+  }
+  // cast is necessary for c++ callers
+  uint32_t* colors = (typeof colors)malloc(sizeof(*colors) * MAXCOLORS);
+  if(colors == NULL){
+    free(rgba);
+    return NULL;
+  }
+  // first we skip the header
+  while(*sx != '#'){
+    ++sx;
+  }
+  // now we build the color table (form: #Pc;Pu;Px;Py;Pz). data starts with
+  // a color spec lacking a semicolon.
+  enum {
+    STATE_WANT_HASH,
+    STATE_WANT_COLOR,
+    STATE_WANT_COLORSEMI,
+    STATE_WANT_COLORSPACE,
+    STATE_WANT_DATA,
+  } state = STATE_WANT_HASH;
+  unsigned color = 0;
+  unsigned x = 0;
+  unsigned y = 0;
+  unsigned rle = 1;
+  while(*sx){
+    if(*sx == '\e'){
+      break;
+    }
+    if(state == STATE_WANT_HASH){
+      if('#' != *sx){
+        goto err;
+      }
+      state = STATE_WANT_COLOR;
+    }else if(state == STATE_WANT_COLOR){
+      if(!isdigit(*sx)){
+        goto err;
+      }
+      color = 0;
+      do{
+        color *= 10;
+        color += *sx - '0';
+        ++sx;
+      }while(isdigit(*sx));
+//std::cerr << "Got color " << color << std::endl;
+      --sx;
+      state = STATE_WANT_COLORSEMI;
+    }else if(state == STATE_WANT_COLORSEMI){
+      // if we get a semicolon, we're a colorspec, otherwise data
+      if(*sx == ';'){
+        state = STATE_WANT_COLORSPACE;
+      }else{
+        state = STATE_WANT_DATA;
+        rle = 1;
+      }
+    }else if(state == STATE_WANT_COLORSPACE){
+      if('2' != *(sx++)){
+        goto err;
+      }
+      if(';' != *(sx++)){
+        goto err;
+      }
+      int r = 0;
+      do{
+        r *= 10;
+        r += *sx - '0';
+        ++sx;
+      }while(isdigit(*sx));
+      if(';' != *(sx++)){
+        goto err;
+      }
+      int g = 0;
+      do{
+        g *= 10;
+        g += *sx - '0';
+        ++sx;
+      }while(isdigit(*sx));
+      if(';' != *(sx++)){
+        goto err;
+      }
+      int b = 0;
+      do{
+        b *= 10;
+        b += *sx - '0';
+        ++sx;
+      }while(isdigit(*sx));
+      uint32_t rgb = htole(0xff000000 + (r << 16u) * 255 / 100 + (g << 8u) * 255 / 100 + b * 255 / 100);
+//std::cerr << "Got color " << color << ": " << r << "/" << g << "/" << b << std::endl;
+      if(color >= MAXCOLORS){
+        goto err;
+      }
+      colors[color] = rgb;
+      state = STATE_WANT_HASH;
+      --sx;
+    }
+    // read until we hit next colorspec
+    if(state == STATE_WANT_DATA){
+//std::cerr << "Character " << *sx << std::endl;
+      if(*sx == '#'){
+        state = STATE_WANT_HASH;
+        --sx;
+      }else if(*sx == '!'){ // RLE
+        ++sx;
+        rle = 0;
+        do{
+          rle *= 10;
+          rle += *sx - '0';
+          ++sx;
+        }while(isdigit(*sx));
+        if(2 >= rle){
+          goto err;
+        }
+        --sx;
+      }else if(*sx == '$'){
+        x = 0;
+        state = STATE_WANT_HASH;
+      }else if(*sx == '-'){
+        x = 0;
+        y += 6;
+        state = STATE_WANT_HASH;
+      }else{
+//std::cerr << "RLE: " << rle << " pos: " << y << "*" << x << std::endl;
+        for(unsigned xpos = x ; xpos < x + rle ; ++xpos){
+          for(unsigned ypos = y ; ypos < y + 6 ; ++ypos){
+            if((*sx - 63) & (1u << (ypos - y))){
+              // ought be an empty pixel
+//std::cerr << *s << " BMAP[" << ypos << "][" << xpos << "] = " << std::hex << colors[color] << std::dec << std::endl;
+              rgba[ypos * lenx + xpos] = colors[color];
+            }
+          }
+        }
+        x += rle;
+        rle = 1;
+      }
+    }
+    ++sx;
+  }
+  free(colors);
+  return rgba;
+
+err:
+  free(rgba);
+  free(colors);
+  return NULL;
+#undef MAXCOLORS
+}
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif

src/tests/sixel.cpp

@@ -2,6 +2,7 @@
 #include "lib/visual-details.h"
 #include <vector>
 #include <iostream>
+#include "lib/sixel.h"
 
 /*
 void print_bmap(const std::vector<uint32_t> rgba, int pixy, int pixx){