Emas and the Unreal Development Kit Workflow

I've been spending some more time with the Unreal Development Kit, as it seems to be trending in the world of games development, and partly to keep my hand in. I've been developing an Emacs based workflow and I thought I'd just quickly blog about it, in case my Emacs Lisp is of any help to any Emacs oldbies confronting this tech. The usual way to develop for it is with nFringe's pixel Mine and Visual Studio. And while Visual Studio is an excellent debugger, it lacks in the actual text editing department, as even Vi users know...

My tools of choice are Emacs AutoComplete mode, which gives Emacs intelli-sense like capabilities over a broad range of languages (it's pretty magical with Lisp, as you'd expect) and the good old Exuberant Ctags, primed to tag Unrealscript, with the following regular expressions in ~/ectags.cnf. I have to say ectags-select is very handy for working with these, as an alternative to the usual way of working with tags in Emacs as it lets you browse the enormous range of options that pop up.

These are the expressions to use for Exubrerant Ctags when tagging Unrealscript.

This is the support code I have: a set of interactive functions for invoking the udk, building code, running the editor. It creates a group of settings that can be customised with M-x customize-group udk. I watch the log in an emacs buffer via global-revert-tail mode. I have not yet added support for UDK log files to compilation mode, but thats an obvious tweak I'll try at some point. I've had enough fiddling with regular expressions for now.

PS: I thought I'd reproduce the unrealscript mode here, just in case. It lives where you put your other extra mode files.

Unrealscript Mode for Emacs Reloaded

I actually started picking up Unreal again, and Unrealscript. My previous attempt at an Unrealscript mode was badly flawed. It was based on CC-mode, which I did not fully pursuade to understand the syntax of Unrealscript. This time, I've gone back to first principles and created simple progmode not derived from cc-mode. This means a loss of functionality, but it does mean correct indenting, and true case insensitivity. I found CC mode would have to be patched to handle a case insensitive language like UnrealScript. Anyway, without further ado, here it is. I reccomend it over the previous ones.

(defvar unrealscript-mode-hook nil)

(defvar unrealscript-mode-map
  (let ((unrealscript-mode-map (make-sparse-keymap)))
 (define-key unrealscript-mode-map "\C-j" 'newline-and-indent)
 unrealscript-mode-map)
  "Keymap for UNREALSCRIPT major mode")


(defconst unrealscript-font-lock-keywords-1
  (list
   '("\\<\\(?:break\\|c\\(?:\\(?:as\\|ontinu\\)e\\)\\|do\\|e\\(?:lse\\|xtends\\)\\|for\\(?:each\\)?\\|i\\(?:f\\|nterface\\)\\|new\\|return\\|switch\\|var\\|while\\|class\\)\\>" . font-lock-keyword-face))
  "Minimal highlighting expressions for UNREALSCRIPT mode.")

(defconst unrealscript-font-lock-keywords-2
  (append unrealscript-font-lock-keywords-1
    (list
     '("\\<\\(?:array\\|b\\(?:ool\\|yte\\)\\|c\\(?:lass\\|o\\(?:erce\\|lor\\|ords\\)\\)\\|de\\(?:faultproperties\\|legate\\)\\|e\\(?:num\\|vent\\)\\|f\\(?:alse\\|loat\\|unction\\)\\|int\\|local\\|name\\|o\\(?:ptional\\|ut\\)\\|plane\\|r\\(?:egion\\|otator\\)\\|st\\(?:ate\\|r\\(?:ing\\|uct\\)\\)\\|true\\|v\\(?:\\(?:a\\|ecto\\)r\\)\\)\\>" . font-lock-keyword-face)))
  "Additional Keywords to highlight in UNREALSCRIPT mode.")


(defconst unrealscript-font-lock-keywords-3
  (append unrealscript-font-lock-keywords-2
    (list
     '("\\<\\(?:A\\(?:bstract\\|llowAbstract\\|uto\\(?:Comment\\|ExpandCategories\\)\\)\\|Co\\(?:llapseCategories\\|nfig\\)\\|D\\(?:ep\\(?:endsOn\\|recated\\)\\|isplayName\\|ontCollapseCategories\\)\\|Edit\\(?:Condition\\|InlineNew\\)\\|FriendlyName\\|Hide\\(?:Categories\\|DropDown\\)\\|I\\(?:\\(?:mplemen\\|nheri\\)ts\\)\\|N\\(?:ative\\(?:Replication\\)?\\|o\\(?:Export\\|nTransient\\|t\\(?:EditInlineNew\\|Placeable\\)\\)\\)\\|P\\(?:erObject\\(?:Config\\|Localized\\)\\|laceable\\)\\|ShowCategories\\|T\\(?:oolTip\\|ransient\\)\\|Within\\)\\>" . font-lock-type-face)
     '("\\<\\(?:auto\\|c\\(?:lient\\|on\\(?:fig\\|st\\)\\)\\|d\\(?:atabinding\\|eprecated\\|uplicatetransient\\)\\|e\\(?:dit\\(?:const\\|fixedsize\\|inline\\(?:use\\)?\\|oronly\\)\\|x\\(?:ec\\|port\\)\\)\\|globalconfig\\|i\\(?:gnores\\|n\\(?:it\\|put\\|stanced\\|terp\\)\\|terator\\)\\|l\\(?:atent\\|ocalized\\)\\|n\\(?:ative\\(?:replication\\)?\\|o\\(?:clear\\|export\\|import\\|ntransactional\\|tforconsole\\)\\)\\|operator\\|p\\(?:o\\(?:\\(?:inte\\|stoperato\\)r\\)\\|r\\(?:eoperator\\|ivate\\|otected\\)\\|ublic\\)\\|re\\(?:liable\\|pnotify\\)\\|s\\(?:erver\\|i\\(?:mulated\\|ngular\\)\\|kip\\|tatic\\)\\|tra\\(?:nsient\\|vel\\)\\|unreliable\\)\\>" . font-lock-keyword-face)
     '("\\<\\(?:A\\(?:bs\\|cos\\|dd\\(?:Item\\)?\\|llActors\\|s\\(?:c\\|in\\)\\|tan\\)\\|B\\(?:asedActors\\|egin\\(?:Play\\|State\\)\\)\\|C\\(?:aps\\|eil\\|h\\(?:ildActors\\|r\\)\\|l\\(?:amp\\|earTimer\\)\\|o\\(?:\\(?:llidingActor\\)?s\\)\\)\\|D\\(?:estroyed\\|i\\(?:\\(?:sabl\\|vid\\)e\\)\\|ynamicActors\\)\\|E\\(?:mpty\\|n\\(?:\\(?:abl\\|dStat\\)e\\)\\|val\\|xp\\)\\|F\\(?:Clamp\\|M\\(?:ax\\|in\\)\\|Rand\\|astTrace\\|in\\(?:d\\|ish\\(?:Anim\\|Interpolation\\)\\)\\)\\|G\\(?:etTimer\\(?:Count\\|Rate\\)\\|oTo\\(?:State\\)?\\)\\|I\\(?:n\\(?:Str\\|itGame\\|sert\\(?:Item\\)?\\|vert\\)\\|s\\(?:\\(?:InStat\\|TimerActiv\\)e\\)\\)\\|L\\(?:e\\(?:ft\\|n\\|rp\\)\\|o\\(?:cs\\|ge\\)\\)\\|M\\(?:ax\\|i\\(?:rrorVectorByNormal\\|[dn]\\)\\)\\|Normal\\|OverlappingActors\\|P\\(?:o\\(?:pState\\|stBeginPlay\\)\\|reBeginPlay\\|ushState\\)\\|R\\(?:and\\|e\\(?:move\\(?:I\\(?:ndex\\|tem\\)\\)?\\|pl\\(?:ace\\)?\\)\\|ight\\|ound\\)\\|S\\(?:et\\(?:State\\|Timer\\)\\|in\\|leep\\|merp\\|p\\(?:awn\\|lit\\)\\|q\\(?:rt\\|uare\\)\\)\\|T\\(?:an\\|ick\\|ouchingActors\\|race\\(?:Actors\\)?\\)\\|V\\(?:Rand\\|Size\\|isible\\(?:\\(?:Colliding\\)?Actors\\)\\)\\|\\(?:ro\\|vec\\)t\\)\\>" . font-lock-function-name-face)))
  "Balls-out highlighting in UNREALSCRIPT mode.")

(defvar unrealscript-font-lock-keywords unrealscript-font-lock-keywords-3
  "Default highlighting expressions for UNREALSCRIPT mode.")


(defvar unrealscript-indent-width 4)

(defun looking-at-unrealscript-indent-keyword ()
  (or (looking-at "^[\t ]*while") (looking-at "^[\t ]*if") (looking-at "^[\t ]*else") (looking-at "^[\t ]*for")))

(defun looking-at-unrealscript-block-end ()  
  (or (looking-at "^[\t ]*end") (and (looking-at "^.*}[ \t]*$") (not (looking-at "^.*{")))))

(defun looking-at-unrealscript-block-start ()
  (or (looking-at "^[\t ]*begin") (and (looking-at "^.*{") (not (looking-at "^.*}[ \t]*$")))))

;; Function to control indenting.
(defun unrealscript-indent-line ()
  "Indent current line as Unrealscript code"
  (interactive)
  ;; Set the point to beginning of line.
  (beginning-of-line)
  (if (bobp)
   (indent-line-to 0)
 (let ((not-indented t) (lines-back 0) cur-indent)
   (if  (looking-at-unrealscript-block-end) ; Check for closing brace
    ;; if we are at the end of a block
    (progn
   (save-excursion
     (forward-line -1)
     (setq lines-back (+ lines-back 1))
     (setq cur-indent (- (current-indentation) unrealscript-indent-width)))
   ;; Safety check to make sure we don't indent negative.
   (if (< cur-indent 0)
    (setq cur-indent 0)))
  ;; else scan backward 
  (save-excursion
    (if (looking-at-unrealscript-block-start) ; Opening block     
     (progn
    (forward-line -1)
    (setq lines-back (+ lines-back 1))
    (setq cur-indent (current-indentation))
    (setq not-indented nil))
   (while not-indented
     (forward-line -1)
     (setq lines-back (+ lines-back 1))
     (if (looking-at-unrealscript-block-end) ;; Closing Block
      (progn
     (setq cur-indent (current-indentation))
     (setq not-indented nil))
    (if (looking-at-unrealscript-block-start)
     (progn
       (setq cur-indent (+ (current-indentation) unrealscript-indent-width))
       (setq not-indented nil))
      (if (looking-at-unrealscript-indent-keyword)
       (progn
      (setq cur-indent (current-indentation))
      (forward-line 1)
      (setq lines-back (- lines-back 1))
      (if (looking-at-unrealscript-block-start)
       (setq not-indented nil) ;; has block
        (if (zerop lines-back) ;; no block
         (progn
        (setq cur-indent (+ cur-indent unrealscript-indent-width))       
        (setq not-indented nil))
       (setq not-indented nil))))
     (if (bobp)
      (setq not-indented nil)))))))))
   (if cur-indent
    (indent-line-to cur-indent)
  (indent-line-to 0))))) 

(defun unrealscript-populate-syntax-table (table)
  "Populate the given syntax table as necessary for a C-like language.
This includes setting ' and \" as string delimiters, and setting up
the comment syntax to handle both line style \"//\" and block style
\"/*\" \"*/\" comments."

  (modify-syntax-entry ?_  "_"    table)
  (modify-syntax-entry ?\\ "\\"    table)
  (modify-syntax-entry ?+  "."    table)
  (modify-syntax-entry ?-  "."    table)
  (modify-syntax-entry ?=  "."    table)
  (modify-syntax-entry ?%  "."    table)
  (modify-syntax-entry ?<  "."    table)
  (modify-syntax-entry ?>  "."    table)
  (modify-syntax-entry ?&  "."    table)
  (modify-syntax-entry ?|  "."    table)
  (modify-syntax-entry ?\' "\""    table)
  (modify-syntax-entry ?\240 "."  table)

  ;; Set up block and line oriented comments.  The new C
  ;; standard mandates both comment styles even in C, so since
  ;; all languages now require dual comments, we make this the
  ;; default.
  (modify-syntax-entry ?/  ". 124b" table)
  (modify-syntax-entry ?*  ". 23" table)

  (modify-syntax-entry ?\n "> b" table)
  ;; Give CR the same syntax as newline, for selective-display
  (modify-syntax-entry ?\^m "> b" table)
  table)

(defvar unrealscript-mode-syntax-table
  (let ((unrealscript-mode-syntax-table (unrealscript-populate-syntax-table (make-syntax-table))))
 unrealscript-mode-syntax-table)
  "Syntax table for unrealscript-mode")

(defun unrealscript-mode ()
  "Major mode for editing Unrealscript files"
  (interactive)
  (kill-all-local-variables)
  (set-syntax-table unrealscript-mode-syntax-table)
  (use-local-map unrealscript-mode-map)
  (setq indent-line-function 'unrealscript-indent-line)
  (setq font-lock-defaults '(unrealscript-font-lock-keywords nil t))
  (setq major-mode 'unrealscript-mode)
  (setq mode-name "UNREALSCRIPT")
  (run-hooks 'unrealscript-mode-hook)
  (setq case-fold-search t)
  (setq font-lock-keywords-case-fold-search t))


(provide 'unrealscript-mode)