From 9492e00318542d8af26e017147517c5a302537c6 Mon Sep 17 00:00:00 2001
From: Amr Gharbeia <amr@gharbeia.net>
Date: Wed, 20 May 2026 11:11:00 -0400
Subject: [PATCH] =?UTF-8?q?Phase=204=20=E2=80=94=20sidebar,=20input,=20cha?=
 =?UTF-8?q?t=20cleanup?=
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

Sidebar: replace manual (incf y) tracking with flat list construction.
sidebar-lines returns (text . color-key) pairs; view-sidebar loops
over them. Version footer stays at h-2. No more fragile y arithmetic.

Input panel: use cl-tty.input text-input's render method instead of
manual word-wrap + cursor-position computation. Layout node set each
frame for dynamic position.

Chat: extract msg->pairs (message to renderable lines) and render-pair
(draw one line pair) as separate functions. Replace reverse-iteration
scroll culling with forward scan that skips by scroll-offset. Same
behavior, less nesting.
---
 org/channel-tui-view.org | 379 ++++++++++++++++++++-------------------
 1 file changed, 193 insertions(+), 186 deletions(-)

diff --git a/org/channel-tui-view.org b/org/channel-tui-view.org
index 8d759f5..58a12bd 100644
--- a/org/channel-tui-view.org
+++ b/org/channel-tui-view.org
@@ -13,15 +13,22 @@
    get amber left border (│), agent messages no border, streaming
    agent gets grey left border. Gate traces/tool calls use ╎ prefix.
 3. (view-input fb w h): renders expanding light grey input box,
-    multi-line word-wrapped prompt, Emacs-style reverse-video cursor,
-   right-aligned lowercase hint at h-2.
-4. (redraw fb w h): wraps view-status/chat/input in begin-sync/end-sync,
+    multi-line word-wrapped prompt, hint bar at h-2. Text and cursor
+   rendered by cl-tty.input text-input's render method.
+4. (view-sidebar fb w h): renders sidebar panels using ~sidebar-lines~.
+5. (sidebar-lines): builds a flat list of (text . color-key) pairs for
+   the sidebar: gate trace, rules, cost, files, version.
+6. (msg->pairs msg index bordered-w unbordered-w is-search): converts
+    a message to renderable ~(border border-color text text-color &optional bg)~
+    lines. Handles markdown, gate trace, tool calls, search highlight.
+7. (render-pair fb hpad y pair): draws one message line pair.
+8. (redraw fb w h): wraps view-status/chat/input in begin-sync/end-sync,
    dispatches per dirty flags, fills global :bg first.
-5. ~cl-tty.box:char-width~ for terminal column width.
+9. ~cl-tty.box:char-width~ for terminal column width.
    ASCII < 128 = 1. CJK, fullwidth, emoji = 2. Combining marks = 0.
    Tab = 8. Used by cl-tty.box:word-wrap for accurate line counting.
-6. (sidebar-visible-p w): returns T if sidebar should show given width W
-   and current :sidebar-mode (:auto >120, :visible always, :hidden never).
+10. (sidebar-visible-p w): returns T if sidebar should show given width W
+    and current :sidebar-mode (:auto >120, :visible always, :hidden never).
 
 ** Status Bar
 
@@ -73,18 +80,91 @@ and current sidebar mode (:auto/:visible/:hidden)."
 #+BEGIN_SRC lisp :tangle /home/user/.local/share/passepartout/lisp/channel-tui-view.lisp
 (in-package :passepartout.channel-tui)
 
+(defun msg->pairs (msg index bordered-w unbordered-w is-search)
+  "Convert a message to a list of (border-str border-color text-str text-color &optional bg) lines."
+  (let* ((role (getf msg :role))
+         (content (getf msg :content))
+         (cs (if is-search (cl-tty.markdown:search-highlight content (st :search-query)) content))
+         (pairs nil)
+         (think-bg (theme-color :thinking-bg))
+         (sym-bdr (theme-color :symbolic-border))
+         (agent-bdr (theme-color :agent-border))
+         (user-bdr (theme-color :user-border))
+         (user-fg (theme-color :user-fg))
+         (agent-fg (theme-color :agent-fg))
+         (system-fg (theme-color :system)))
+    (case role
+      (:user
+       (dolist (l (cl-tty.box:word-wrap cs bordered-w))
+         (push (list "│" user-bdr l user-fg) pairs)))
+      (:agent
+       (let* ((streaming (getf msg :streaming))
+              (think-rect (if streaming think-bg nil))
+              (bdr (if streaming nil agent-bdr))
+              (bstr (if streaming nil "│"))
+              (wrap-w (if streaming unbordered-w bordered-w))
+              (nodes (cl-tty.markdown:parse-blocks cs))
+              (raw-body (or (and nodes (cl-tty.markdown:render-md nodes)) (list "")))
+              (body (mapcan (lambda (l) (cl-tty.box:word-wrap l wrap-w)) raw-body)))
+         (dolist (l body)
+           (push (list bstr bdr l agent-fg think-rect) pairs))))
+      (t (dolist (l (cl-tty.box:word-wrap cs unbordered-w))
+           (push (list nil nil l system-fg) pairs))))
+    ;; Gate trace
+    (let ((gt (getf msg :gate-trace)))
+      (when (and gt (eq role :agent))
+        (if (member index (st :collapsed-gates))
+            (push (list "│" sym-bdr (format nil "Gate trace: ~a gates" (length gt)) sym-bdr) pairs)
+            (dolist (entry (passepartout::gate-trace-lines gt))
+              (let ((ec (theme-color (getf (cdr entry) :fgcolor))))
+                (dolist (l (cl-tty.box:word-wrap (car entry) bordered-w))
+                  (push (list "│" sym-bdr l ec) pairs)))))))
+    ;; Tool calls
+    (let ((tc (getf msg :tool-calls)))
+      (when tc
+        (if (member index (st :collapsed-tools))
+            (let* ((n (or (getf (first tc) :name) "tool"))
+                   (d (or (getf (first tc) :duration) 0.0)))
+              (push (list "│" (theme-color :tool-done) (format nil "~a … ~,1fs" n d) (theme-color :tool-done)) pairs))
+            (dolist (call tc)
+              (let* ((name (or (getf call :name) "tool"))
+                     (dur (or (getf call :duration) 0.0))
+                     (st (getf call :status))
+                     (out (getf call :output))
+                     (bc (theme-color
+                          (cond ((eq st :running) :tool-running)
+                                ((eq st :error) :tool-error)
+                                (t :tool-done))))
+                     (pfx (cond ((eq st :error) "✗") ((eq st :running) "●") (t "✓")))
+                     (ol (when out (cl-tty.box:word-wrap out bordered-w))))
+                (push (list "│" bc (format nil "~a ~a  ~,1fs" pfx name dur) bc) pairs)
+                (dolist (l ol)
+                  (push (list "│" bc l bc) pairs)))))))
+    (nreverse pairs)))
+
+(defun render-pair (fb hpad y pair)
+  "Draw a single (border-str border-color text-str text-color &optional bg) line."
+  (destructuring-bind (bstr bcolor tstr tcolor &optional rect-bg) pair
+    (when rect-bg
+      (cl-tty.backend:draw-rect fb 0 y 1 1 :bg rect-bg))
+    (let ((has-border (and bstr (> (length bstr) 0))))
+      (when has-border
+        (cl-tty.backend:draw-text fb hpad y bstr bcolor (theme-color :bg)))
+      (cl-tty.backend:draw-text fb (+ hpad (if has-border 2 0)) y tstr tcolor (theme-color :bg)))))
+
 (defun view-chat (fb w h)
   (let* ((w (or (and (numberp w) (> w 0) w) 80))
          (h (or (and (numberp h) (> h 0) h) 24))
-          (hpad 2)
-          (sidebar-w (if (sidebar-visible-p w) (or (st :sidebar-width) 42) 0))
-          (chat-w (- w sidebar-w))
-          (msgs (st :messages)) (total (length msgs))
-          (panel-top (input-panel-top chat-w h))
-          (max-lines (max 0 panel-top)) (is-search (st :search-mode))
-          (bordered-w (- chat-w (* 2 hpad) 2))
-          (unbordered-w (- chat-w (* 2 hpad)))
-          (y 0))
+         (hpad 2)
+         (sidebar-w (if (sidebar-visible-p w) (or (st :sidebar-width) 42) 0))
+         (chat-w (- w sidebar-w))
+         (msgs (st :messages)) (total (length msgs))
+         (panel-top (input-panel-top chat-w h))
+         (max-lines (max 0 panel-top)) (is-search (st :search-mode))
+         (bordered-w (- chat-w (* 2 hpad) 2))
+         (unbordered-w (- chat-w (* 2 hpad)))
+         (y 0))
+    ;; Search header
     (when is-search
       (let* ((matches (st :search-matches)) (idx (st :search-match-idx))
              (query (st :search-query))
@@ -92,93 +172,27 @@ and current sidebar mode (:auto/:visible/:hidden)."
                           (length matches) query (1+ idx) (length matches))))
         (cl-tty.backend:draw-text fb hpad y hdr (theme-color :accent) nil)
         (incf y) (decf max-lines)))
-    (let ((msg-lines (make-array total)) (msg-heights (make-array total)))
-      (dotimes (i total)
-        (let* ((msg (aref msgs i)) (role (getf msg :role))
-               (content (getf msg :content))
-               (cs (if is-search (cl-tty.markdown:search-highlight content (st :search-query)) content))
-               (pairs nil)
-               (think-bg (theme-color :thinking-bg))
-               (sym-bdr (theme-color :symbolic-border))
-               (agent-bdr (theme-color :agent-border))
-               (user-bdr (theme-color :user-border))
-               (user-fg (theme-color :user-fg))
-               (agent-fg (theme-color :agent-fg))
-               (system-fg (theme-color :system)))
-          (case role
-            (:user
-             (dolist (l (cl-tty.box:word-wrap cs bordered-w))
-               (push (list "│" user-bdr l user-fg) pairs)))
-            (             :agent
-             (let* ((streaming (getf msg :streaming))
-                    (think-rect (if streaming think-bg nil))
-                    (bdr (if streaming nil agent-bdr))
-                    (bstr (if streaming nil "│"))
-                    (wrap-w (if streaming unbordered-w bordered-w))
-                    (nodes (cl-tty.markdown:parse-blocks cs))
-                    (raw-body (or (and nodes (cl-tty.markdown:render-md nodes)) (list "")))
-                    (body (mapcan (lambda (l) (cl-tty.box:word-wrap l wrap-w)) raw-body)))
-               (dolist (l body)
-                 (push (list bstr bdr l agent-fg think-rect) pairs))))
-            (t (dolist (l (cl-tty.box:word-wrap cs unbordered-w))
-                 (push (list nil nil l system-fg) pairs))))
-          ;; Gate trace
-          (let ((gt (getf msg :gate-trace)))
-            (when (and gt (eq role :agent))
-              (if (member i (st :collapsed-gates))
-                  (push (list "│" sym-bdr (format nil "Gate trace: ~a gates" (length gt)) sym-bdr) pairs)
-                  (dolist (entry (passepartout::gate-trace-lines gt))
-                    (let ((ec (theme-color (getf (cdr entry) :fgcolor))))
-                      (dolist (l (cl-tty.box:word-wrap (car entry) bordered-w))
-                        (push (list "│" sym-bdr l ec) pairs)))))))
-          ;; Tool calls
-          (let ((tc (getf msg :tool-calls)))
-            (when tc
-              (if (member i (st :collapsed-tools))
-                  (let* ((n (or (getf (first tc) :name) "tool"))
-                         (d (or (getf (first tc) :duration) 0.0)))
-                    (push (list "│" (theme-color :tool-done) (format nil "~a … ~,1fs" n d) (theme-color :tool-done)) pairs))
-                  (dolist (call tc)
-                    (let* ((name (or (getf call :name) "tool"))
-                           (dur (or (getf call :duration) 0.0))
-                           (st (getf call :status))
-                           (out (getf call :output))
-                           (bc (theme-color
-                                (cond ((eq st :running) :tool-running)
-                                      ((eq st :error) :tool-error)
-                                      (t :tool-done))))
-                           (pfx (cond ((eq st :error) "✗") ((eq st :running) "●") (t "✓")))
-                           (ol (when out (cl-tty.box:word-wrap out bordered-w))))
-                      (push (list "│" bc (format nil "~a ~a  ~,1fs" pfx name dur) bc) pairs)
-                      (dolist (l ol)
-                        (push (list "│" bc l bc) pairs)))))))
-          (setf (aref msg-lines i) (nreverse pairs))
-          (setf (aref msg-heights i) (length pairs))))
-      (let ((msg-count 0) (lines-remaining max-lines))
-        (loop for i from (1- total) downto 0
-              while (> lines-remaining 0)
-               do (let ((mh (aref msg-heights i))
-                          (spacer (if (< i (1- total)) 1 0)))
-                   (if (<= (+ mh spacer) lines-remaining)
-                       (progn (decf lines-remaining (+ mh spacer)) (incf msg-count))
-                       (setf lines-remaining 0))))
-        (let* ((scroll-skip (st :scroll-offset))
-               (start (max 0 (- total msg-count scroll-skip))))
-            (loop for i from start below total while (< y panel-top)
-                  do (let ((pairs (aref msg-lines i)))
-                     (dolist (pair pairs)
-                        (when (>= y panel-top) (return))
-                          (destructuring-bind (bstr bcolor tstr tcolor &optional rect-bg) pair
-                            (when rect-bg
-                              (cl-tty.backend:draw-rect fb 0 y 1 1 :bg rect-bg))
-                            (let ((has-border (and bstr (> (length bstr) 0))))
-                              (when has-border
-                                (cl-tty.backend:draw-text fb hpad y bstr bcolor (theme-color :bg)))
-                              (cl-tty.backend:draw-text fb (+ hpad (if has-border 2 0)) y tstr tcolor (theme-color :bg))))
-                        (incf y))
-                       ;; spacer between message blocks
-                        (when (< i (1- total))
-                          (incf y)))))))))
+    ;; Build all message lines once
+    (let* ((msg-lines (map 'vector
+                           (lambda (msg i) (msg->pairs msg i bordered-w unbordered-w is-search))
+                           msgs
+                           (make-array total :initial-contents (loop for i below total collect i))))
+           (heights (map 'vector #'length msg-lines))
+           (scroll-skip (st :scroll-offset))
+           (i 0))
+      ;; Forward scan: skip messages scrolled past, then render visible ones
+      (loop while (< i total)
+            do (let ((hgt (aref heights i)))
+                 (if (> scroll-skip 0)
+                     (decf scroll-skip hgt)
+                     (let ((msg-y y))
+                       (dolist (pair (aref msg-lines i))
+                         (when (>= msg-y panel-top) (return))
+                         (render-pair fb hpad msg-y pair)
+                         (incf msg-y))
+                       (setf y (1+ msg-y))  ;; +1 spacer between messages
+                       (when (>= y panel-top) (return)))))
+            (incf i)))))
 #+END_SRC
 
 ** Input Line
@@ -192,36 +206,23 @@ and current sidebar mode (:auto/:visible/:hidden)."
          (inner-w (- chat-w (* 2 hpad)))
          (prompt-w (- inner-w 2))
          (input (st :text-input))
-         (text (cl-tty.input:text-input-value input))
-         (pos (cl-tty.input:text-input-cursor input))
-         (lines (cl-tty.box:word-wrap text prompt-w))
-         (n-lines (max 1 (length lines)))
+         (n-lines (max 1 (length (cl-tty.box:word-wrap (cl-tty.input:text-input-value input) prompt-w))))
           (panel-rows (max 4 (+ n-lines 2)))
           (panel-top (input-panel-top chat-w h))
          (bg-i (theme-color :bg-input))
-         (input-fg (theme-color :input-fg))
          (hint-fg (theme-color :hint)))
     ;; Fill input panel
     (cl-tty.backend:draw-rect fb hpad panel-top inner-w panel-rows :bg bg-i)
     ;; Speaker lines for all input rows
     (dotimes (r panel-rows)
       (cl-tty.backend:draw-text fb hpad (+ panel-top r) "│" (theme-color :input-prompt) nil))
-    ;; Draw each wrapped input line
-    (let ((accum 0) (cursor-line 0) (cursor-col 0))
-      (dotimes (i n-lines)
-        (let* ((line (nth i lines))
-               (row (+ panel-top 1 i))
-               (len (length line)))
-          (when (>= row (- h 4)) (return))
-          (cl-tty.backend:draw-text fb (+ hpad 2) row line input-fg nil)
-          (when (and (>= pos accum) (or (< pos (+ accum len)) (= i (1- n-lines))))
-            (setf cursor-line i
-                  cursor-col (- pos accum)))
-          (incf accum (1+ len))))
-      ;; Draw block cursor at insertion point
-      (let* ((cx (+ hpad 2 cursor-col))
-             (cy (+ panel-top 1 cursor-line)))
-        (cl-tty.backend:draw-text fb cx cy "█" :bright-white nil)))
+    ;; Render text-input widget (word-wrap + cursor)
+    (let ((ln (make-layout-node)))
+      (setf (layout-node-x ln) (+ hpad 2)
+            (layout-node-y ln) (1+ panel-top)
+            (layout-node-width ln) prompt-w)
+      (setf (cl-tty.input:text-input-layout-node input) ln)
+      (cl-tty.box:render input fb))
     ;; Hint bar at h-2
     (let* ((focal (or (st :foveal-id) "-"))
            (focal-str (format nil "F:~a" focal))
@@ -248,73 +249,79 @@ and current sidebar mode (:auto/:visible/:hidden)."
 
 ** Sidebar
 #+BEGIN_SRC lisp :tangle /home/user/.local/share/passepartout/lisp/channel-tui-view.lisp
+(defun sidebar-lines ()
+  "Collect all sidebar lines as (text . color-key) pairs."
+  (let* ((msgs (st :messages))
+         (last-gt (loop for i from (1- (length msgs)) downto 0
+                        for m = (aref msgs i)
+                        when (getf m :gate-trace)
+                        return (getf m :gate-trace)))
+         (blocked (loop for i below (length msgs)
+                        for m = (aref msgs i)
+                        sum (loop for g in (getf m :gate-trace)
+                                  count (eq (getf g :result) :blocked))))
+         (ver (or (st :daemon-version) ""))
+         (ver-label (if (> (length ver) 0) (format nil "passepartout ~a" ver) "passepartout"))
+         (dot (if (st :connected) "●" "○"))
+         (dot-color (if (st :connected) :dot-connected :dot-disconnected)))
+    (append
+     ;; Gate Trace
+     '("GATE TRACE" . :accent)
+     (if last-gt
+         (mapcan (lambda (g)
+                   (let* ((name (getf g :gate))
+                          (result (getf g :result))
+                          (reason (getf g :reason))
+                          (glyph (case result (:passed "✓") (:blocked "✗") (:approval "→") (t "?")))
+                          (color (case result
+                                   (:passed :tool-done)
+                                   (:blocked :error)
+                                   (:approval :input-prompt)
+                                   (t :dim))))
+                     (if reason
+                         (list (cons (format nil "  ~a ~a" glyph name) color)
+                               (cons (format nil "    ~a" reason) :dim))
+                         (list (cons (format nil "  ~a ~a" glyph name) color)))))
+                 last-gt)
+         '((cons "  (none)" :dim)))
+     ;; Rules
+     '("" nil)
+     '("RULES" . :accent)
+     (list (cons (format nil "  ~d active" (or (st :rule-count) 0)) :agent-fg))
+     (list (cons (format nil "  ~d blocked" blocked)
+                 (if (> blocked 0) :error :dim)))
+     ;; Cost
+     '("" nil)
+     '("COST" . :accent)
+     (list (cons (format nil "  $~,2f" (or (st :session-cost) 0.0)) :status-fg))
+     ;; Files
+     '("" nil)
+     '("FILES" . :accent)
+     '("  (not yet)" . :dim)
+     ;; spacer
+     '("" nil)
+     ;; Version footer — rendered at h-2, not in the loop
+     (list (cons (format nil "~a ~a" dot ver-label) dot-color)))))
+
 (defun view-sidebar (fb w h)
   (let* ((w (or (and (numberp w) (> w 0) w) 80))
          (h (or (and (numberp h) (> h 0) h) 24))
          (x (- w (or (st :sidebar-width) 42)))
-         (bg-panel (theme-color :bg-panel))
-         (y 0))
-    (cl-tty.backend:draw-rect fb x 0 (- w x) (1- h) :bg bg-panel)
-    (cl-tty.backend:draw-text fb x (1- h) (make-string (- w x) :initial-element #\Space) nil bg-panel)
-    ;; Gate Trace — from latest agent message
-    (cl-tty.backend:draw-text fb (+ x 2) (incf y) "GATE TRACE" (theme-color :accent) bg-panel)
-    (incf y)
-    (let* ((msgs (st :messages))
-           (last-gt (loop for i from (1- (length msgs)) downto 0
-                          for m = (aref msgs i)
-                          when (getf m :gate-trace)
-                          return (getf m :gate-trace))))
-      (if last-gt
-          (dolist (g last-gt)
-            (let* ((name (getf g :gate))
-                   (result (getf g :result))
-                   (reason (getf g :reason))
-                   (glyph (case result (:passed "✓") (:blocked "✗") (:approval "→") (t "?")))
-                   (color (case result
-                            (:passed (theme-color :tool-done))
-                            (:blocked (theme-color :error))
-                            (:approval (theme-color :input-prompt))
-                            (t (theme-color :dim)))))
-              (cl-tty.backend:draw-text fb (+ x 2) (incf y) (format nil "  ~a ~a" glyph name) color bg-panel)
-              (when reason
-                (incf y)
-                (cl-tty.backend:draw-text fb (+ x 4) (incf y) reason (theme-color :dim) bg-panel))))
-          (cl-tty.backend:draw-text fb (+ x 2) (incf y) "  (none)" (theme-color :dim) bg-panel))
-      (incf y 2))
-    ;; Rules + Block Count
-    (let ((blocked (loop for i below (length (st :messages))
-                         for m = (aref (st :messages) i)
-                         sum (loop for g in (getf m :gate-trace)
-                                   count (eq (getf g :result) :blocked)))))
-      (cl-tty.backend:draw-text fb (+ x 2) (incf y) "RULES" (theme-color :accent) bg-panel)
-      (incf y)
-      (cl-tty.backend:draw-text fb (+ x 2) (incf y)
-                               (format nil "  ~d active" (or (st :rule-count) 0))
-                               (theme-color :agent-fg) bg-panel)
-      (incf y)
-      (cl-tty.backend:draw-text fb (+ x 2) (incf y)
-                               (format nil "  ~d blocked" blocked)
-                               (if (> blocked 0) (theme-color :error) (theme-color :dim)) bg-panel)
-      (incf y 2))
-    ;; Cost
-    (cl-tty.backend:draw-text fb (+ x 2) (incf y) "COST" (theme-color :accent) bg-panel)
-    (incf y)
-    (cl-tty.backend:draw-text fb (+ x 2) (incf y)
-                             (format nil "  $~,2f" (or (st :session-cost) 0.0))
-                             (theme-color :status-fg) bg-panel)
-    (incf y 2)
-    ;; Files (stub)
-    (cl-tty.backend:draw-text fb (+ x 2) (incf y) "FILES" (theme-color :accent) bg-panel)
-    (incf y)
-    (cl-tty.backend:draw-text fb (+ x 2) (incf y) "  (not yet)" (theme-color :dim) bg-panel)
-    (incf y 2)
-    ;; Version footer
-    (let* ((ver (or (st :daemon-version) ""))
-           (ver-label (if (> (length ver) 0) (format nil "passepartout ~a" ver) "passepartout"))
-           (dot (if (st :connected) "●" "○"))
-           (dot-color (if (st :connected) (theme-color :dot-connected) (theme-color :dot-disconnected))))
-      (cl-tty.backend:draw-text fb (+ x 2) (- h 2) dot dot-color bg-panel)
-      (cl-tty.backend:draw-text fb (+ x 4) (- h 2) ver-label (theme-color :text-muted) bg-panel))))
+         (lines (sidebar-lines))
+         (content-lines (butlast lines))
+         (footer-line (car (last lines))))
+    (cl-tty.backend:draw-rect fb x 0 (- w x) (1- h) :bg (theme-color :bg-panel))
+    (loop for (text . color-key) in content-lines
+          for y from 0
+          when text
+            do (cl-tty.backend:draw-text fb (+ x 2) y text
+                                          (if color-key (theme-color color-key) (theme-color :dim))
+                                          (theme-color :bg-panel)))
+    ;; Version footer at h-2
+    (when footer-line
+      (cl-tty.backend:draw-text fb (+ x 2) (- h 2) (car footer-line)
+                                (theme-color (cdr footer-line))
+                                (theme-color :bg-panel)))))
 #+END_SRC
 
 ** Redraw (dirty-flag dispatch)