Improve 2020/ferguson1/termcaps.c

2020/ferguson1/termcaps.c

@@ -1,11 +1,13 @@
-/* This will imperfectly:
+/* ioccc/2020/ferguson1 - Snake terminal testing utility
- 
+ *
-   (1)	Test if terminal supports the features Snake uses.
+ * This will imperfectly:
-   (2)	Report terminal (and playing) size(s).
+ *
-   (3)	Estimates the minimum number of columns to play unhindered (based on the
+ * (0)	Test if terminal supports the features Snake uses.
- 	size, max size and growth rate).
+ * (1)	Report terminal (and playing) size(s).
-   (4)	Reports the max size of the Snake and the number of bugs required to
+ * (2)	Estimates the minimum number of columns to play unhindered (based on the
- 	reach that size (doesn't use shedding).
+ *      size, max size and growth rate).
+ * (3)	Reports the max size of the Snake and the number of bugs required to
+ *	reach that size but doesn't use shedding.
  */
 
 #include <curses.h>
@@ -84,7 +86,7 @@ int main(void)
     {
 	i[caps].sup = tigetstr(caps[i].caps);
 	/* tigetstr() returns (char *)-1 if the capability name isn't
-	 * recognised; check for this before suggesting it's supported: */
+	 * recognised; check for this before suggesting it's (un)?supported: */
 	if (caps[i].sup == (char *)-1)
 	    caps[i].sup = NULL;
 	if (!caps[i].sup) ++k;
@@ -119,10 +121,10 @@ int main(void)
 
     rows = 14 + b(Y)*2 + a(y)*2 + a(x)*2 + b(N);
     if (x < (int)rows + 1) ++k;
-    printf("at least %zu columns recommended for snake size %-5zu (is %d)\n", rows+1,Y, x);
+    printf("at least %zu columns (currently %d) recommended for snake size %-5zu\n", rows+1,x, Y);
 
     rows = 14 + b(K)*2 + a(y)*2 + a(x)*2 + b(c(K,X));
-    printf("at least %zu columns recommended for snake size %-5zu (is %d)\n\n", rows + 1, K, x);
+    printf("at least %zu columns (currently %d) recommended for capped snake size %-5zu\n\n", rows + 1,x, K);
 
 
     if (!k)

2020/ferguson1/terminals.md

@@ -42,54 +42,68 @@ for the capabilities I use in the entry.
 It also tries to determine the minimum number of columns to play without the
 status line overflowing - even with the dynamic length. Try:
 
-	    $ make test
+```sh
+$ make test
+```
 
-This compiles the program and runs it; you should see something like:
+This compiles the program [termcaps.c](termcaps.c) and runs it; you should see something like:
 
-	    terminal supports cursor movement
-	    terminal supports making cursor invisible
-	    terminal supports bold
-	    terminal supports colours
 
-	    terminal rows  42 (39  playable)
+```
-	    terminal cols 157 (155 playable)
+terminal supports cursor movement
+terminal supports making cursor invisible
+terminal supports bold
+terminal supports colours
 
-	    snake size:   997 (max size: 6006)
+terminal rows  41 (38  playable)
-		  bugs:   199 (max size: 1201)
+terminal cols 155 (153 playable)
 
-	    at least 34 columns recommended for snake size 997   (is 157)
+snake size:   997 (max size: 5776)
-	    at least 37 columns recommended for snake size 6006  (is 157)
+      bugs:   199 (max size: 1155)
 
-	    No problems detected.
+at least 34 columns (currently 155) recommended for snake size 997
+at least 37 columns (currently 155) recommended for capped snake size 5776
 
-If I pass in any of the variables **GROW**, **MAXSIZE**, **SIZE** and/or
+No problems detected.
-**LINES** or **COLUMNS** it bases its calculations on those variables. For
+```
+
+Terminal rows and cols are the current values (the number of columns shown later
+as well). The snake size is the default size to win (based on the variables, see
+below). The `max size: 5776` is the capped size (or 'capsize'). The 199 bugs is
+approximately the `snake_size / growth_size` i.e. how many bugs it
+will take to win the game. The max bugs in the `bugs` line is approximately
+`max_snake_size / growth_size` i.e. how many bugs it'll take to win at the
+maximum (capped) snake size.
+
+If I pass in any of the variables **`GROW`**, **`MAXSIZE`**, **`SIZE`** and/or
+**`LINES`** or **`COLUMNS`** it bases its calculations on those variables. For
 example:
 
-	    $ MAXSIZE=-1 GROW=1  make test
+```sh
-	    terminal supports cursor movement
+terminal supports cursor movement
-	    terminal supports making cursor invisible
+terminal supports making cursor invisible
-	    terminal supports bold
+terminal supports bold
-	    terminal supports colours
+terminal supports colours
 
-	    terminal rows  42 (39  playable)
+terminal rows  41 (38  playable)
-	    terminal cols 157 (155 playable)
+terminal cols 155 (153 playable)
 
-	    snake size:  6006 (max size: 6006)
+snake size:  5776 (max size: 5776)
-		  bugs:  6001 (max size: 6001)
+      bugs:  5771 (max size: 5771)
 
-	    at least 37 columns recommended for snake size 6006  (is 157)
+at least 37 columns (currently 155) recommended for snake size 5776 
-	    at least 37 columns recommended for snake size 6006  (is 157)
+at least 37 columns (currently 155) recommended for capped snake size 5776 
 
-	    No problems detected.
+No problems detected.
+```
 
-
+As you can see it tells you the max size (the 'capsized' snake) as well as the
-As you can see it tells you the max size (the 'capsized' snake) as well as
+requested max size (if the requested size is bigger than the capped size then it
-the requested max size (if the requested size is bigger than the capsize then it
 will be set to that value instead) of the snake. The capped size is like in the
 Snake game itself but the suggested minimum number of columns is based on a
 number of variables.
 
+
 If I were to do the above but set columns to less < 35 then there would be a
 problem. But why if the utility recommends at least 37? This is because the
 max size of the snake also depends on the terminal size. This utility is not
@@ -108,7 +122,7 @@ this should give you an idea.
 
 If there are any problems it will say how many (fatal and otherwise). The fatal
 problems are if curses fails to initialise or if movement of cursor cannot be
-done (both seem odd).
+done (both seem unlikely to happen nowadays).
 
 Both scripts run this utility and prompt if there are any problems;
 you can continue either way.