grosciteco: basic support for GNU pic graphics

* The line drawing algorithm currently works only with tbl, though.
* Also only straight lines are currently supported.
* This was meant for rendering presentations in SciTECO - it's not currently
  used or planned to be used in the manpages.
  Although we might well add pic graphics to the manpages in the future.

1 files changed, 52 insertions, 26 deletions

diff --git a/doc/grosciteco.tes b/doc/grosciteco.tes
index 1e57b52..b220041 100755
--- a/doc/grosciteco.tes
+++ b/doc/grosciteco.tes
@@ -50,6 +50,38 @@ EBN[input]
   Q.n<.-Z"= 1; ' 0A-10"= 1; ' D>
 ].n }
 
+!* draw a line to (h,v) *!
+!* FIXME: Works only for straight lines *!
+@[line]{ U.[to.v] U.[to.h]
+  Q.[to.h]-Q[pos.h]"= Q.[to.v]-Q[pos.v]"=  ' '
+  [* EB
+  Q.[to.h]-Q[pos.h]"=
+    !* vertical line *!
+    Q.[to.v]-Q[pos.v]"< Q[pos.v]U.v Q.[to.v]U[pos.v] | Q.[to.v]U.v '
+    1:M[move] %[pos.v] .-Z"= I R '
+    -A-9472"= 0A-9472"= I┬ | I┐ '
+            | 0A-9472"= I┌ | I╷ ' '
+    Q.v-Q[pos.v]<
+      1:M[move] %[pos.v] .-Z"= I R '
+      -A-9472"= 0A-9472"= I┼ | I┤ '
+              | 0A-9472"= I├ | I│ ' '
+    >
+    1:M[move] .-Z"= I R '
+    -A-9472"= 0A-9472"= I┴ | I┘ '
+            | 0A-9472"= I└ | I╵ ' '
+    Q.[to.v]U[pos.v]
+  |
+    !* horizontal line
+       FIXME: works only if horizonal lines are drawn first. *!
+    Q.[to.h]-Q[pos.h]"< Q[pos.h]U.h Q.[to.h]U[pos.h] | Q.[to.h]U.h '
+    Q.h-Q[pos.h]+1<
+      1:M[move] I─ %[pos.h]
+    >
+    Q.[to.h]U[pos.h]
+  '
+  ]*
+}
+
 !* style last N glyphs/characters *!
 1U[default-style]
 @[style]{ [.l
@@ -208,34 +240,28 @@ EBN[input]
         !cmd.DFd!
           :M#sc F<
 
+        !cmd.DFg!
+          :M#sw :M#gi :M#sc F<
+
     !cmd.Dl!
       :M#sw :M#gi/Q[res.h]+Q[pos.h]U.[to.h] :M#gi/Q[res.v]+Q[pos.v]U.[to.v] :M#sc
-      [* EB
-      Q.[to.h]-Q[pos.h]"=
-        !* vertical line *!
-        Q.[to.v]-Q[pos.v]"< Q[pos.v]U.v Q.[to.v]U[pos.v] | Q.[to.v]U.v '
-        1:M[move] %[pos.v] .-Z"= I R '
-        -A-9472"= 0A-9472"= I┬ | I┐ '
-                | 0A-9472"= I┌ | I╷ ' '
-        Q.v-Q[pos.v]<
-          1:M[move] %[pos.v] .-Z"= I R '
-          -A-9472"= 0A-9472"= I┼ | I┤ '
-                  | 0A-9472"= I├ | I│ ' '
-        >
-        1:M[move] .-Z"= I R '
-        -A-9472"= 0A-9472"= I┴ | I┘ '
-                | 0A-9472"= I└ | I╵ ' '
-        Q.[to.v]U[pos.v]
-      |
-        !* horizontal line
-           FIXME: works only if horizonal lines are drawn first. *!
-        Q.[to.h]-Q[pos.h]"< Q[pos.h]U.h Q.[to.h]U[pos.h] | Q.[to.h]U.h '
-        Q.h-Q[pos.h]+1<
-          1:M[move] I─ %[pos.h]
-        >
-        Q.[to.h]U[pos.h]
-      '
-      ]* F<
+      Q.[to.h],Q.[to.v]M[line] F<
+
+    !cmd.Dp!
+    !cmd.DP!
+      :M#sw Q[pos.h]U.[start.h] Q[pos.v]U.[start.v]
+      <
+        :M#gi/Q[res.h]U.h Q.h+Q[pos.h]U.[to.h] :M#gi/Q[res.v]U.v Q.v+Q[pos.v]U.[to.v]
+        Q.h%.[inc.h] Q.v%.[inc.v]
+        Q.[to.h],Q.[to.v]M[line]
+        0A-10"= 1; '
+      >
+      Q.[start.h],Q.[start.v]M[line]
+      Q.[inc.h]%[pos.h] Q.[inc.v]%[pos.v]
+      :M#sc F<
+
+    !cmd.Dt!
+      :M#sw :M#gi/Q[res.h]%[pos.h] :M#sw :M#gi :M#sc F<
 
   !cmd.t!
     :M#sw .(:M#sa).X.w