add notcurses_lex_blitter()

NEWS.md

@@ -1,6 +1,11 @@
 This document attempts to list user-visible changes and any major internal
 rearrangements of Notcurses.
 
+* 1.6.6 (2020-07-19)
+  * `notcurses-pydemo` is now only installed alongside the Python module,
+    using setuptools. CMake no longer installs it.
+  * Added `notcurses_lex_blitter()` and `notcurses_str_scalemode()`.
+
 * 1.6.5 (2020-07-19)
   * No user-visible changes.
 

USAGE.md

@@ -2639,6 +2639,9 @@ typedef enum {
   NCBLIT_SIXEL,   // 6 rows, 1 col (RGB), spotty support among terminals
 } ncblitter_e;
 
+// Lex a blitter.
+int notcurses_lex_blitter(const char* op, ncblitter_e* blitter);
+
 // Get the name of a blitter.
 const char* notcurses_str_blitter(ncblitter_e blitter);
 
@@ -2671,6 +2674,12 @@ typedef enum {
   NCSCALE_STRETCH,
 } ncscale_e;
 
+// Lex a visual scaling mode (one of "none", "stretch", or "scale").
+int notcurses_lex_scalemode(const char* op, ncscale_e* scalemode);
+
+// Get the name of a scaling mode.
+const char* notcurses_str_scalemode(ncscale_e scalemode);
+
 // the streaming operation ceases immediately, and that value is propagated out.
 // The recommended absolute display time target is passed in 'tspec'.
 typedef int (*streamcb)(struct ncplane*, struct ncvisual*,

doc/man/man3/notcurses_visual.3.md

@@ -82,6 +82,12 @@ typedef int (*streamcb)(struct notcurses*, struct ncvisual*, void*);
 
 **char* ncvisual_subtitle(const struct ncvisual* ncv);**
 
+**int notcurses_lex_scalemode(const char* op, ncscale_e* scalemode);**
+
+**const char* notcurses_str_scalemode(ncscale_e scalemode);**
+
+**int notcurses_lex_blitter(const char* op, ncblitter_e* blitter);**
+
 **const char* notcurses_str_blitter(ncblitter_e blitter);**
 
 # DESCRIPTION

include/notcurses/notcurses.h

@@ -895,12 +895,18 @@ typedef struct notcurses_options {
 // there can be four numbers separated by commas.
 API int notcurses_lex_margins(const char* op, notcurses_options* opts);
 
+// Lex a blitter.
+API int notcurses_lex_blitter(const char* op, ncblitter_e* blitter);
+
 // Get the name of a blitter.
 API const char* notcurses_str_blitter(ncblitter_e blitter);
 
 // Lex a visual scaling mode (one of "none", "stretch", or "scale").
 API int notcurses_lex_scalemode(const char* op, ncscale_e* scalemode);
 
+// Get the name of a scaling mode.
+API const char* notcurses_str_scalemode(ncscale_e scalemode);
+
 // Initialize a notcurses context on the connected terminal at 'fp'. 'fp' must
 // be a tty. You'll usually want stdout. NULL can be supplied for 'fp', in
 // which case /dev/tty will be opened. Returns NULL on error, including any

python/src/notcurses/build_notcurses.py

@@ -146,6 +146,7 @@ typedef enum {
   NCBLIT_SIXEL,   // 6 rows, 1 col (RGB)
 } ncblitter_e;
 const char* notcurses_str_blitter(ncblitter_e blitter);
+int notcurses_lex_blitter(const char* op, ncblitter_e* blitter);
 uint32_t* ncplane_rgba(const struct ncplane* nc, ncblitter_e blit, int begy, int begx, int leny, int lenx);
 char* ncplane_contents(const struct ncplane* nc, int begy, int begx, int leny, int lenx);
 void* ncplane_set_userptr(struct ncplane* n, void* opaque);
@@ -273,6 +274,8 @@ typedef enum {
   NCSCALE_SCALE,
   NCSCALE_STRETCH,
 } ncscale_e;
+int notcurses_lex_scalemode(const char* op, ncscale_e* scalemode);
+const char* notcurses_str_scalemode(ncscale_e scalemode);
 struct ncvisual* ncvisual_from_file(const char* file, nc_err_e* ncerr);
 struct ncvisual* ncvisual_from_rgba(const void* rgba, int rows, int rowstride, int cols);
 struct ncvisual* ncvisual_from_bgra(const void* rgba, int rows, int rowstride, int cols);

src/lib/blit.c

@@ -499,6 +499,22 @@ const struct blitset notcurses_blitters[] = {
      .blit = NULL,           .name = NULL,            .fill = false,  },
 };
 
+int notcurses_lex_blitter(const char* op, ncblitter_e* blitter){
+  const struct blitset* bset = notcurses_blitters;
+  while(bset->name){
+    if(strcasecmp(bset->name, op) == 0){
+      *blitter = bset->geom;
+      return 0;
+    }
+    ++bset;
+  }
+  if(strcasecmp("default", op) == 0){
+    *blitter = NCBLIT_DEFAULT;
+    return 0;
+  }
+  return -1;
+}
+
 const char* notcurses_str_blitter(ncblitter_e blitter){
   if(blitter == NCBLIT_DEFAULT){
     return "default";