Switched to using temp buffer for processing string.

diff --git a/sixel.el b/sixel.el
index cd7fd31..ae7a2aa 100644 (file)
--- a/sixel.el
+++ b/sixel.el
@@ -14,12 +14,6 @@
   "Retrieve data string."
   (substring string (1+ (string-match "q" string))))
 
-(defvar sixel-colour-map nil
-  "Map of two-character names to RGB colour triples.")
-
-(defvar sixel-current-colour nil
-  "Current colour.")
-
 (defun sixel-compute-row-length (string)
   (apply 'max
          (mapcar
@@ -46,45 +40,51 @@ with TAG."
   (let ((sixel (elt (symbol-value row-variable) index)))
     (sixel-tag-bits sixel (- char 63) tag)))
 
-(defun sixel-process-row (string)
-  (let ((idx-in 0)
-        (idx-out 0)
-        result)
-    (while (< idx-in (length string))
-      (let (trunc-string (substring string index-in))
+(defun sixel-process-data (string)
+  "Convert sixel string into a list of lists representing individual sixels."
+  (with-temp-buffer
+    (insert string)
+    (goto-char (point-min))
+    (let ((idx-out 0)
+          this-row rows
+          current-colour colour-map
+          finished)
+      (while  (not finished)
         (cond
-         ((string-match "^#\\([0-9]+\\);\\([0-9]+\\);\\([0-9]+\\);\\([0-9]+\\);\\([0-9]+\\)"
-                        trunc-string)
-          (let ((tag (intern (string-to (match-string 1 trunc-string))))
-                (mode (match-string 2 trunc-string))
-                (r (string-to-number (match-string 3 trunc-string)))
-                (g (string-to-number (match-string 4 trunc-string)))
-                (b (string-to-number (match-string 5 trunc-string))))
-            (add-to-list 'sixel-colour-map (list (tag r g b)))
-            (setq idx-in (match-end 0))))
-         ((string-match "^#\\([0-9]+\\)" trunc-string)
+         ((looking-at "#\\([0-9]+\\);\\([0-9]+\\);\\([0-9]+\\);\\([0-9]+\\);\\([0-9]+\\)")
+          (let ((tag (intern (match-string 1)))
+                (mode (match-string 2))
+                (r (string-to-number (match-string 3)))
+                (g (string-to-number (match-string 4)))
+                (b (string-to-number (match-string 5))))
+            (push (list tag r g b) colour-map)))
+
+         ((looking-at "#\\([0-9]+\\)")
           (let ((tag (intern (match-string 1 trunc-string))))
-            (setq sixel-current-colour tag)
-            (setq idx-in (match-end 0))))
-         ((string-match "^$" trunc-string)
-          (setq idx-out 0)
-          (setq idx-in (match-end 0 trunc-string)))
-         ((string-match "^!\\([0-9]+\\)\\([?-~]\\)" trunc-string)
-          (let ((repeat-count (string-to-number (match-string 1 trunc-string)))
+            (setq current-colour tag)))
+
+         ((looking-at "$")
+          (setq idx-out 0))
+
+         ((looking-at "^-")
+          (push this-row 'rows)
+          (setq this-row nil)
+          (setq idx-out 0))
+
+         ((looking-at "^!\\([0-9]+\\)\\([?-~]\\)")
+          (let ((repeat-count (string-to-number (match-string 1)))
                 (char (elt (match-string 2 trunc-string) 0)))
             (dotimes (i repeat-count)
-              (sixel-tag-sixel-in-row 'result idx-out char sixel-current-colour)
-              (setq idx-out (+1 idx-out)))))
-         ((string-match "^\\([?-~]\\)" trunc-string)
+              (sixel-tag-sixel-in-row 'result idx-out char current-colour))))
+
+         ((looking-at "^\\([?-~]\\)")
           (let ((char (elt (match-string 1 trunc-string) 0)))
-            (sixel-tag-sixel-in-row 'result idx-out char sixel-current-colour))
-          (setq idx-out (+1 idx-out))))))))
-              
-(sixel-get-rows test-string)
+            (sixel-tag-sixel-in-row 'result idx-out char current-colour)))
+
+         ((= (point) (point-max))
+          (setq finished t))
 
-(defun sixel-to-xpm (string)
-  "Converts the given sixel string into an XPM image."
+         (t (error "Invalid characters found in input string.")))
 
-  (let* ((sp (split-string string "q"))
-         (control-string (car sp))
-         ())))
+        (goto-char (match-end 0)))
+      (push this-row 'rows))))