diff --git a/plot-lib/plot/private/common/plot-device.rkt b/plot-lib/plot/private/common/plot-device.rkt
index c692bf60..9a1c81cc 100644
--- a/plot-lib/plot/private/common/plot-device.rkt
+++ b/plot-lib/plot/private/common/plot-device.rkt
@@ -636,8 +636,8 @@
          ;; get max widths and heights per row/column
          (define-values (max-label-widths max-label-heights)
            (let-values ([(width height)
-                        (for/fold ([width  : (HashTable Integer Exact-Rational) #hash()]
-                                   [height : (HashTable Integer Exact-Rational) #hash()])
+                        (for/fold ([width  : (Immutable-HashTable Integer Exact-Rational) #hash()]
+                                   [height : (Immutable-HashTable Integer Exact-Rational) #hash()])
                                   ([label (in-list labels)]
                                    [k (in-naturals)])
                           (define-values (i j)
@@ -666,7 +666,7 @@
          ;; different gaps
          (define-values (horiz-gap min-label-height baseline _1)
            (get-text-extent " "))
-      
+
          (define top-gap baseline)
          (define bottom-gap (* 1/2 baseline))
          (define in-label-gap (* 3 horiz-gap))
@@ -724,7 +724,7 @@
          (define draw-x-mins (for/list : (Listof Real)
                                ([x (in-list label-x-mins)]
                                 [w (in-list max-label-widths)]) (+ x w in-label-gap)))
-         
+
          (values legend-rect max-label-heights
                  draw-x-size label-x-mins draw-x-mins
                  draw-y-size label-y-mins
@@ -801,7 +801,7 @@
           (define max-label-height (list-ref max-label-heights i))
           (define label-y-min (+ legend-entry-y-min
                                  (* 1/2 (- max-label-height label-height))))
-          
+
           (if (pict? label)
               (draw-pict label (vector label-x-min label-y-min) 'top-left 0)
               (draw-text label (vector label-x-min label-y-min) 'top-left 0 0 #t))
diff --git a/plot-lib/plot/private/plot3d/bsp-trees.rkt b/plot-lib/plot/private/plot3d/bsp-trees.rkt
index d34b3842..52c5b997 100644
--- a/plot-lib/plot/private/plot3d/bsp-trees.rkt
+++ b/plot-lib/plot/private/plot3d/bsp-trees.rkt
@@ -7,26 +7,26 @@
 
 (provide (all-defined-out))
 
-(: build-bsp-trees (-> (HashTable Integer (Listof BSP-Shape))
-                       (HashTable Integer BSP-Tree)))
+(: build-bsp-trees (-> (Immutable-HashTable Integer (Listof BSP-Shape))
+                       (Immutable-HashTable Integer BSP-Tree)))
 (define (build-bsp-trees structural-shapes)
-  (for/hasheq : (HashTable Integer BSP-Tree) ([(layer ss)  (in-hash structural-shapes)])
+  (for/hasheq : (Immutable-HashTable Integer BSP-Tree) ([(layer ss)  (in-hash structural-shapes)])
     (values layer (build-bsp-tree ss))))
 
-(: walk-bsp-trees (-> (HashTable Integer BSP-Tree)
+(: walk-bsp-trees (-> (Immutable-HashTable Integer BSP-Tree)
                       FlVector
-                      (HashTable Integer (Listof BSP-Shape))
-                      (HashTable Integer (Listof BSP-Shape))))
+                      (Immutable-HashTable Integer (Listof BSP-Shape))
+                      (Immutable-HashTable Integer (Listof BSP-Shape))))
 (define (walk-bsp-trees bsp-trees view-dir detail-shapes)
   (define vx (flvector-ref view-dir 0))
   (define vy (flvector-ref view-dir 1))
   (define vz (flvector-ref view-dir 2))
-  
+
   (define layers (sort (append (hash-keys bsp-trees) (hash-keys detail-shapes)) >))
-  (for/hasheq : (HashTable Integer (Listof BSP-Shape)) ([layer  (in-list layers)])
+  (for/hasheq : (Immutable-HashTable Integer (Listof BSP-Shape)) ([layer  (in-list layers)])
     (define bsp (hash-ref bsp-trees layer (λ () (bsp-leaf empty))))
     (define ss (hash-ref detail-shapes layer (λ () empty)))
-    
+
     (: in-order-ss (Listof BSP-Shape))
     (define in-order-ss
       (let loop ([bsp  (bsp-tree-insert bsp ss)])
@@ -40,5 +40,5 @@
            (if (cos-angle . > . -1e-16)
                (append (loop neg) (loop pos))
                (append (loop pos) (loop neg)))])))
-    
+
     (values layer in-order-ss)))
diff --git a/plot-lib/plot/private/plot3d/bsp.rkt b/plot-lib/plot/private/plot3d/bsp.rkt
index 89920188..72587691 100644
--- a/plot-lib/plot/private/plot3d/bsp.rkt
+++ b/plot-lib/plot/private/plot3d/bsp.rkt
@@ -143,7 +143,7 @@
                          [(n . = . 2)  (list (line data (first vs) (second vs)))]
                          [else  (list (lines data vs))]))
                  vss)))
-         
+
          (define-values (vss1 vss2) (split-lines3d vs plane))
          (values (vertices->lines vss2) (vertices->lines vss1))]))
 
@@ -254,7 +254,7 @@
              (define n (length ivls))
              (define-values (ivls1 ivls2) (split-at ivls (quotient n 2)))
              (interval-list-union (loop ivls1) (loop ivls2))])))
-  
+
   (cond [(empty? ivls)  #f]
         [(empty? (rest ivls))  #f]
         [else
@@ -408,7 +408,7 @@
      (match s
        [(points _ vs)
         (if (empty? vs) empty (list s))]
-       [(line _ v1 v2) 
+       [(line _ v1 v2)
         (if (equal? v1 v2) empty (list s))]
        [(poly data vs ls norm)
         (let-values ([(vs ls)  (canonical-polygon3d vs ls)])
@@ -513,17 +513,17 @@
     [else
      (define axes (vertices->axes (bsp-polys->vertices ps)))
      (define center (list->flvector (map axis-mid axes)))
-     
+
      ;; Planes defined by neighboring polygon vertices
      (define polygon-planes (delay (sort-planes (append* (map bsp-poly-planes ps)) center)))
-     
+
      (: try-bsp-split/polygon-planes (-> Boolean (U #f BSP-Tree)))
      ;; Tries splitting using polygon-planes
      (define (try-bsp-split/polygon-planes disjoint?)
        (define planes (force polygon-planes))
        (cond [(and disjoint? ((length planes) . > . 10))  #f]
              [else  (try-bsp-split/planes ss planes disjoint?)]))
-     
+
      (let* ([bsp  #f]
             [bsp  (if bsp bsp (try-bsp-split/axial-planes ss axes))]
             [bsp  (if bsp bsp (try-bsp-split/bounding-planes ss ps center))]
@@ -543,17 +543,17 @@
     [else
      (define axes (vertices->axes (bsp-lines->vertices ls)))
      (define center (list->flvector (map axis-mid axes)))
-     
+
      ;; Planes defined by line segments and basis vectors (i.e. one basis in normal is zero)
      (define line-planes (delay (sort-planes (append* (map bsp-line-planes ls)) center)))
-     
+
      (: try-bsp-split/line-planes (-> Boolean (U #f BSP-Tree)))
      ;; Tries splitting using line-planes
      (define (try-bsp-split/line-planes disjoint?)
        (define planes (force line-planes))
        (cond [(and disjoint? ((length planes) . > . 10))  #f]
              [else  (try-bsp-split/planes ss planes disjoint?)]))
-     
+
      (let* ([bsp  #f]
             [bsp  (if bsp bsp (try-bsp-split/axial-planes ss axes))]
             [bsp  (if bsp bsp (try-bsp-split/line-planes #t))]
@@ -573,7 +573,7 @@
      (define axes (vertices->axes (append (append* (map lines-vertices ls))
                                           (append* (map points-vertices ps)))))
      (define center (list->flvector (map axis-mid axes)))
-     
+
      (: try-nondisjoint-split (-> (U #f BSP-Tree)))
      (define (try-nondisjoint-split)
        (match-define (axis i size _mn _mx mid) (argmax axis-size axes))
@@ -581,7 +581,7 @@
              [else
               (define plane (axial-plane i mid))
               (try-bsp-split ss plane #f (λ () #f))]))
-     
+
      (let* ([bsp  #f]
             [bsp  (if bsp bsp (try-bsp-split/axial-planes ss axes))]
             [bsp  (if bsp bsp (try-nondisjoint-split))])
diff --git a/plot-lib/plot/private/plot3d/plot-area.rkt b/plot-lib/plot/private/plot3d/plot-area.rkt
index 27af815e..eb43be4f 100644
--- a/plot-lib/plot/private/plot3d/plot-area.rkt
+++ b/plot-lib/plot/private/plot3d/plot-area.rkt
@@ -34,9 +34,9 @@
 (: plot3d-subdivisions (Parameterof Natural))
 (define plot3d-subdivisions (make-parameter 0))
 
-(struct render-tasks ([structural-shapes : (HashTable Integer (Listof BSP-Shape))]
-                      [detail-shapes : (HashTable Integer (Listof BSP-Shape))]
-                      [bsp-trees : (HashTable Integer BSP-Tree)]))
+(struct render-tasks ([structural-shapes : (Immutable-HashTable Integer (Listof BSP-Shape))]
+                      [detail-shapes : (Immutable-HashTable Integer (Listof BSP-Shape))]
+                      [bsp-trees : (Immutable-HashTable Integer BSP-Tree)]))
 
 (struct data ([alpha : Nonnegative-Real]) #:transparent)
 
@@ -153,16 +153,16 @@
     (init-field bounds-rect rx-ticks rx-far-ticks ry-ticks ry-far-ticks rz-ticks rz-far-ticks legend)
     (init-field dc dc-x-min dc-y-min dc-x-size dc-y-size aspect-ratio)
     (super-new)
-    
+
     (: pd (Instance Plot-Device%))
     (define pd (make-object plot-device% dc dc-x-min dc-y-min dc-x-size dc-y-size))
     (send pd reset-drawing-params)
-    
+
     (: char-height Exact-Rational)
     (: half-char-height Exact-Rational)
     (define char-height (send pd get-char-height))
     (define half-char-height (* 1/2 char-height))
-    
+
     (define: x-min : Real  0)
     (define: x-max : Real  0)
     (define: y-min : Real  0)
@@ -170,7 +170,7 @@
     (define: z-min : Real  0)
     (define: z-max : Real  0)
     (let ()
-      (match-define (vector (ivl x-min-val x-max-val) 
+      (match-define (vector (ivl x-min-val x-max-val)
                             (ivl y-min-val y-max-val)
                             (ivl z-min-val z-max-val))
         bounds-rect)
@@ -183,7 +183,7 @@
              (set! z-max z-max-val)]
             [else
              (raise-argument-error '3d-plot-area% "rect-known?" bounds-rect)]))
-    
+
     (: x-size Real)
     (: y-size Real)
     (: z-size Real)
@@ -196,7 +196,7 @@
     (define x-mid (* 1/2 (+ x-min x-max)))
     (define y-mid (* 1/2 (+ y-min y-max)))
     (define z-mid (* 1/2 (+ z-min z-max)))
-    
+
     (: clipping? Boolean)
     (: clip-x-min Real)
     (: clip-x-max Real)
@@ -211,7 +211,7 @@
     (define clip-y-max y-max)
     (define clip-z-min z-min)
     (define clip-z-max z-max)
-    
+
     (define/public (put-clip-rect rect)
       (match-define (vector (ivl rx-min rx-max) (ivl ry-min ry-max) (ivl rz-min rz-max)) rect)
       (define cx-min (if rx-min (max* x-min rx-min) x-min))
@@ -233,30 +233,30 @@
         (set! clip-z-min cz-min)
         (set! clip-z-max cz-max))
       (set! clipping? #t))
-    
+
     (define/public (clear-clip-rect) (set! clipping? #f))
-    
+
     (: in-bounds? (-> (Vectorof Real) Boolean))
     (define/private (in-bounds? v)
       (or (not clipping?) (point-in-bounds? v
                                             clip-x-min clip-x-max
                                             clip-y-min clip-y-max
                                             clip-z-min clip-z-max)))
-    
+
     (define/public (get-x-ticks) x-ticks)
     (define/public (get-y-ticks) y-ticks)
     (define/public (get-z-ticks) z-ticks)
     (define/public (get-x-far-ticks) x-far-ticks)
     (define/public (get-y-far-ticks) y-far-ticks)
     (define/public (get-z-far-ticks) z-far-ticks)
-    
+
     (define/public (get-bounds-rect) bounds-rect)
-    
+
     (define/public (get-clip-rect)
       (if clipping?
           (vector (ivl clip-x-min clip-x-max) (ivl clip-y-min clip-y-max) (ivl clip-z-min clip-z-max))
           bounds-rect))
-    
+
     (: angle Real)
     (: altitude Real)
     (: theta Real)
@@ -267,14 +267,14 @@
     ;; or 270, the x/y/z tick labels are drawn on the left side.
     (define theta (+ (degrees->radians angle) 0.00001))
     (define rho (degrees->radians altitude))
-    
+
     ;; There are four coordinate systems:
     ;;  1. Plot coordinates (original, user-facing coordinate system)
     ;;  2. Normalized coordinates (from plot coordinates: for each axis: transform, center, and scale
     ;;     to [-0.5,0.5]) - these are always flvectors
     ;;  3. View coordinates (from normalized coordinates: rotate)
     ;;  4. Device context coordinates (from view coordinates: project to 2D)
-    
+
     (define: fx : (-> Real Real)  (λ ([x : Real]) x))
     (define: gx : (-> Real Real)  (λ ([x : Real]) x))
     (define: fy : (-> Real Real)  (λ ([y : Real]) y))
@@ -291,13 +291,13 @@
       (set! gy gy-val)
       (set! fz fz-val)
       (set! gz gz-val))
-    
+
     (: identity-transforms? Boolean)
     (define identity-transforms?
       (and (equal? (plot-x-transform) id-transform)
            (equal? (plot-y-transform) id-transform)
            (equal? (plot-z-transform) id-transform)))
-    
+
     (: plot->norm (-> (Vectorof Real) FlVector))
     (define/private (plot->norm v)
       (match v
@@ -320,14 +320,14 @@
          [s (in-list (list x-size y-size z-size))]
          [g (in-list (list gx gy gz))])
         (g (+ (* c s) m))))
-    
+
     (: rotate-theta-matrix M3)
     (: rotate-rho-matrix M3)
     (: rotation-matrix M3)
     (define rotate-theta-matrix (m3-rotate-z theta))
     (define rotate-rho-matrix (m3-rotate-x rho))
     (define rotation-matrix (m3* rotate-rho-matrix rotate-theta-matrix))
-    
+
     (: norm->view (-> FlVector FlVector))
     (: plot->view (-> (Vectorof Real) FlVector))
     (: plot->view/no-rho (-> (Vectorof Real) FlVector))
@@ -338,17 +338,17 @@
     (define/private (plot->view/no-rho v) (m3-apply rotate-theta-matrix (plot->norm v)))
     (define/private (norm->view/no-rho v) (m3-apply rotate-theta-matrix v))
     (define/private (rotate/rho v) (m3-apply rotate-rho-matrix v))
-    
+
     (: unrotation-matrix M3)
     (: view->norm (-> FlVector FlVector))
     (define unrotation-matrix (m3-transpose rotation-matrix))
     (define/private (view->norm v) (m3-apply unrotation-matrix v))
-    
+
     (: plot->dc (-> (Vectorof Real) (Vectorof Real)))
-    (: norm->dc (-> FlVector (Vectorof Real)))    
+    (: norm->dc (-> FlVector (Vectorof Real)))
     (define (plot->dc v) (view->dc (plot->view v)))
     (define/private (norm->dc v) (view->dc (norm->view v)))
-    
+
     (define: view-x-size : Real  0)
     (define: view-y-size : Real  0)
     (define: view-z-size : Real  0)
@@ -365,7 +365,7 @@
       (set! view-x-size view-x-size-val)
       (set! view-y-size view-y-size-val)
       (set! view-z-size view-z-size-val))
-    
+
     (: make-view->dc (-> Real Real Real Real (-> FlVector (Vectorof Real))))
     (define/private (make-view->dc left right top bottom)
       (define area-x-min left)
@@ -400,7 +400,7 @@
     (: dc->plot (-> (Vectorof Real)  (Vectorof Real)))
     (define (dc->plot v)
       (norm->plot (view->norm (dc->view v))))
-    
+
     (: title-margin Real)
     (define title-margin
       (let ([title (plot-title)])
@@ -455,36 +455,36 @@
       (match-define (vector dx dy) (v- (norm->dc (flvector 0.5 0.0 0.0))
                                        (norm->dc (flvector -0.5 0.0 0.0))))
       (- (atan2 (- dy) dx)))
-    
+
     (: y-axis-angle (-> Real))
     (define (y-axis-angle)
       (match-define (vector dx dy) (v- (norm->dc (flvector 0.0 0.5 0.0))
                                        (norm->dc (flvector 0.0 -0.5 0.0))))
       (- (atan2 (- dy) dx)))
-    
+
     (: x-axis-dir (-> (Vectorof Real)))
     (define (x-axis-dir)
       (vnormalize (v- (norm->dc (flvector 0.5 0.0 0.0))
                       (norm->dc (flvector -0.5 0.0 0.0)))))
-    
+
     (: y-axis-dir (-> (Vectorof Real)))
     (define (y-axis-dir)
       (vnormalize (v- (norm->dc (flvector 0.0 0.5 0.0))
                       (norm->dc (flvector 0.0 -0.5 0.0)))))
-    
+
     ;; ===============================================================================================
     ;; Tick and label constants
-    
+
     (: tick-radius Real)
     (: half-tick-radius Real)
     (define tick-radius (* 1/2 (plot-tick-size)))
     (define half-tick-radius (* 1/2 tick-radius))
-    
+
     (: x-axis-y-min? Boolean)
     (: y-axis-x-min? Boolean)
     (define x-axis-y-min? ((cos theta) . >= . 0))  ; #t iff x near labels should be drawn at y-min
     (define y-axis-x-min? ((sin theta) . >= . 0))  ; #t iff y near labels should be drawn at x-min
-    
+
     (: x-axis-y Real)
     (: y-axis-x Real)
     (: z-axis-x Real)
@@ -493,7 +493,7 @@
     (define y-axis-x (if y-axis-x-min? x-min x-max))
     (define z-axis-x (if x-axis-y-min? x-min x-max))
     (define z-axis-y (if y-axis-x-min? y-max y-min))
-    
+
     (: x-far-axis-y Real)
     (: y-far-axis-x Real)
     (: z-far-axis-x Real)
@@ -502,7 +502,7 @@
     (define y-far-axis-x (if y-axis-x-min? x-max x-min))
     (define z-far-axis-x (if x-axis-y-min? x-max x-min))
     (define z-far-axis-y (if y-axis-x-min? y-min y-max))
-    
+
     (: x-axis-norm-y Flonum)
     (: y-axis-norm-x Flonum)
     (: z-axis-norm-x Flonum)
@@ -511,7 +511,7 @@
     (define y-axis-norm-x (if y-axis-x-min? -0.5 0.5))
     (define z-axis-norm-x (if x-axis-y-min? -0.5 0.5))
     (define z-axis-norm-y (if y-axis-x-min? 0.5 -0.5))
-    
+
     (: x-far-axis-norm-y Flonum)
     (: y-far-axis-norm-x Flonum)
     (: z-far-axis-norm-x Flonum)
@@ -520,29 +520,29 @@
     (define y-far-axis-norm-x (if y-axis-x-min? 0.5 -0.5))
     (define z-far-axis-norm-x (if x-axis-y-min? 0.5 -0.5))
     (define z-far-axis-norm-y (if y-axis-x-min? -0.5 0.5))
-    
+
     (: near-dist^2 Real)
     (define near-dist^2 (sqr (* 3 (plot-line-width))))
-    
+
     (: vnear? (-> (Vectorof Real) (Vectorof Real) Boolean))
     (define/private (vnear? v1 v2)
       ((vmag^2 (v- (plot->dc v1) (plot->dc v2))) . <= . near-dist^2))
-    
+
     (: x-ticks-near? (-> Real (-> pre-tick pre-tick Boolean)))
     (define/private ((x-ticks-near? y) t1 t2)
       (vnear? (vector (pre-tick-value t1) y z-min)
               (vector (pre-tick-value t2) y z-min)))
-    
+
     (: y-ticks-near? (-> Real (-> pre-tick pre-tick Boolean)))
     (define/private ((y-ticks-near? x) t1 t2)
       (vnear? (vector x (pre-tick-value t1) z-min)
               (vector x (pre-tick-value t2) z-min)))
-    
+
     (: z-ticks-near? (-> Real Real (-> pre-tick pre-tick Boolean)))
     (define/private ((z-ticks-near? x y) t1 t2)
       (vnear? (vector x y (pre-tick-value t1))
               (vector x y (pre-tick-value t2))))
-    
+
     (: x-ticks (Listof tick))
     (: y-ticks (Listof tick))
     (: z-ticks (Listof tick))
@@ -558,7 +558,7 @@
       (collapse-ticks (filter (λ ([t : tick]) (<= z-min (pre-tick-value t) z-max))
                               (map tick-inexact->exact rz-ticks))
                       (z-ticks-near? z-axis-x z-axis-y)))
-    
+
     (: x-far-ticks (Listof tick))
     (: y-far-ticks (Listof tick))
     (: z-far-ticks (Listof tick))
@@ -574,18 +574,18 @@
       (collapse-ticks (filter (λ ([t : tick]) (<= z-min (pre-tick-value t) z-max))
                               (map tick-inexact->exact rz-far-ticks))
                       (z-ticks-near? z-far-axis-x z-far-axis-y)))
-    
+
     ;; ===============================================================================================
     ;; Tick and label parameters, and fixpoint margin computation
-    
+
     ;; From here through "All parameters" are functions that compute *just the parameters* of ticks
     ;; and labels that will be drawn on the plot. We have to separate computing parameters from
     ;; actually drawing the ticks and labels so we can solve for the plot margins using a fixpoint
     ;; computation. See ../common/draw.rkt for more explanation. (Search for 'margin-fixpoint'.)
-    
+
     ;; -----------------------------------------------------------------------------------------------
     ;; Tick parameters
-    
+
     (: x-tick-value->view (-> Real FlVector))
     (: y-tick-value->view (-> Real FlVector))
     (: x-far-tick-value->view (-> Real FlVector))
@@ -594,7 +594,7 @@
     (define/private (y-tick-value->view y) (plot->view (vector y-axis-x y z-min)))
     (define/private (x-far-tick-value->view x) (plot->view (vector x x-far-axis-y z-min)))
     (define/private (y-far-tick-value->view y) (plot->view (vector y-far-axis-x y z-min)))
-    
+
     (: x-tick-value->dc (-> Real (Vectorof Real)))
     (: y-tick-value->dc (-> Real (Vectorof Real)))
     (: z-tick-value->dc (-> Real (Vectorof Real)))
@@ -607,49 +607,49 @@
     (define/private (x-far-tick-value->dc x) (view->dc (x-far-tick-value->view x)))
     (define/private (y-far-tick-value->dc y) (view->dc (y-far-tick-value->view y)))
     (define/private (z-far-tick-value->dc z) (plot->dc (vector z-far-axis-x z-far-axis-y z)))
-    
+
     (: get-tick-params (-> (Listof tick) (-> Real (Vectorof Real)) Real (Listof Tick-Params)))
     (define/private (get-tick-params ts tick-value->dc angle)
       (for/list : (Listof Tick-Params) ([t  (in-list ts)])
         (match-define (tick p major? _) t)
         (list major? (tick-value->dc p) (if major? tick-radius half-tick-radius) angle)))
-    
+
     (: get-x-tick-params (-> (Listof Tick-Params)))
     (define (get-x-tick-params)
       (if (plot-x-axis?)
           (get-tick-params x-ticks (λ ([x : Real]) (x-tick-value->dc x)) (y-axis-angle))
           empty))
-    
+
     (: get-y-tick-params (-> (Listof Tick-Params)))
     (define (get-y-tick-params)
       (if (plot-y-axis?)
           (get-tick-params y-ticks (λ ([y : Real]) (y-tick-value->dc y)) (x-axis-angle))
           empty))
-    
+
     (: get-z-tick-params (-> (Listof Tick-Params)))
     (define (get-z-tick-params)
       (if (plot-z-axis?)
           (get-tick-params z-ticks (λ ([z : Real]) (z-tick-value->dc z)) 0)
           empty))
-    
+
     (: get-x-far-tick-params (-> (Listof Tick-Params)))
     (define (get-x-far-tick-params)
       (if (plot-x-far-axis?)
           (get-tick-params x-far-ticks (λ ([x : Real]) (x-far-tick-value->dc x)) (y-axis-angle))
           empty))
-    
+
     (: get-y-far-tick-params (-> (Listof Tick-Params)))
     (define (get-y-far-tick-params)
       (if (plot-y-far-axis?)
           (get-tick-params y-far-ticks (λ ([y : Real]) (y-far-tick-value->dc y)) (x-axis-angle))
           empty))
-    
+
     (: get-z-far-tick-params (-> (Listof Tick-Params)))
     (define (get-z-far-tick-params)
       (if (plot-z-far-axis?)
           (get-tick-params z-far-ticks (λ ([z : Real]) (z-far-tick-value->dc z)) 0)
           empty))
-    
+
     ;; -----------------------------------------------------------------------------------------------
     ;; Tick label parameters
 
@@ -677,13 +677,13 @@
         (if (eq? flag 'auto)
             (and (plot-z-axis?) (equal? z-ticks z-far-ticks))
             flag)))
-    
+
     (: sort-ticks (-> (Listof tick) (-> Real FlVector) (Listof tick)))
     (define/private (sort-ticks ts tick-value->view)
       ((inst sort tick Flonum)
        ts fl> #:key (λ ([t : tick]) (flvector-ref (tick-value->view (pre-tick-value t)) 2))
        #:cache-keys? #t))
-    
+
     (: x-tick-label-anchor Anchor)
     (define x-tick-label-anchor
       (let ([s  (sin theta)])
@@ -692,7 +692,7 @@
               [(s . < . (sin (degrees->radians 22.5)))   'top]
               [(s . < . (sin (degrees->radians 67.5)))   (if x-axis-y-min? 'top-left 'top-right)]
               [else                                      (if x-axis-y-min? 'top-left 'top-right)])))
-    
+
     (: y-tick-label-anchor Anchor)
     (define y-tick-label-anchor
       (let ([c  (cos theta)])
@@ -701,17 +701,17 @@
               [(c . > . (cos (degrees->radians 112.5)))  'top]
               [(c . > . (cos (degrees->radians 157.5)))  (if y-axis-x-min? 'top-left 'top-right)]
               [else                                      (if y-axis-x-min? 'top-left 'top-right)])))
-    
+
     (: z-tick-label-anchor Anchor)
     (define z-tick-label-anchor 'right)
-    
+
     (: x-far-tick-label-anchor Anchor)
     (: y-far-tick-label-anchor Anchor)
     (: z-far-tick-label-anchor Anchor)
     (define x-far-tick-label-anchor (opposite-anchor x-tick-label-anchor))
     (define y-far-tick-label-anchor (opposite-anchor y-tick-label-anchor))
     (define z-far-tick-label-anchor 'left)
-    
+
     (: get-tick-label-params (-> (Listof tick) (-> Real (Vectorof Real)) (Vectorof Real) Anchor
                                  (Listof Label-Params)))
     (define/private (get-tick-label-params ts tick-value->dc offset-dir anchor)
@@ -719,7 +719,7 @@
       (for/list : (Listof Label-Params) ([t  (in-list ts)] #:when (pre-tick-major? t))
         (match-define (tick x _ label) t)
         (list label (v+ (tick-value->dc x) (v* offset-dir dist)) anchor 0)))
-    
+
     (: get-x-tick-label-params (-> (Listof Label-Params)))
     (define (get-x-tick-label-params)
       (if (and (plot-x-axis?) draw-x-tick-labels?)
@@ -729,7 +729,7 @@
                                    offset
                                    x-tick-label-anchor))
           empty))
-    
+
     (: get-y-tick-label-params (-> (Listof Label-Params)))
     (define (get-y-tick-label-params)
       (if (and (plot-y-axis?) draw-y-tick-labels?)
@@ -739,7 +739,7 @@
                                    offset
                                    y-tick-label-anchor))
           empty))
-    
+
     (: get-z-tick-label-params (-> (Listof Label-Params)))
     (define (get-z-tick-label-params)
       (if (and (plot-z-axis?) draw-z-tick-labels?)
@@ -748,7 +748,7 @@
                                  #(-1 0)
                                  z-tick-label-anchor)
           empty))
-    
+
     (: get-x-far-tick-label-params (-> (Listof Label-Params)))
     (define (get-x-far-tick-label-params)
       (if (and (plot-x-far-axis?) draw-x-far-tick-labels?)
@@ -759,7 +759,7 @@
                                    offset
                                    x-far-tick-label-anchor))
           empty))
-    
+
     (: get-y-far-tick-label-params (-> (Listof Label-Params)))
     (define (get-y-far-tick-label-params)
       (if (and (plot-y-far-axis?) draw-y-far-tick-labels?)
@@ -770,7 +770,7 @@
                                    offset
                                    y-far-tick-label-anchor))
           empty))
-    
+
     (: get-z-far-tick-label-params (-> (Listof Label-Params)))
     (define (get-z-far-tick-label-params)
       (if (and (plot-z-far-axis?) draw-z-far-tick-labels?)
@@ -779,16 +779,16 @@
                                  #(1 0)
                                  z-far-tick-label-anchor)
           empty))
-    
+
     ;; -----------------------------------------------------------------------------------------------
     ;; Axis label parameters
-    
+
     (: max-tick-offset (-> (Listof tick) Real))
     (define/private (max-tick-offset ts)
       (cond [(empty? ts)  0]
             [(ormap pre-tick-major? ts)  (+ (pen-gap) tick-radius)]
             [else  (+ (pen-gap) (* 1/4 (plot-tick-size)))]))
-    
+
     (: max-x-tick-offset Real)
     (: max-y-tick-offset Real)
     (: max-x-far-tick-offset Real)
@@ -797,16 +797,16 @@
     (define max-y-tick-offset (if (plot-y-axis?) (max-tick-offset y-ticks) 0))
     (define max-x-far-tick-offset (if (plot-x-far-axis?) (max-tick-offset x-far-ticks) 0))
     (define max-y-far-tick-offset (if (plot-y-far-axis?) (max-tick-offset y-far-ticks) 0))
-    
+
     (: max-tick-label-height (-> (Listof tick) Real))
     (define/private (max-tick-label-height ts)
       (if (ormap pre-tick-major? ts) char-height 0))
-    
+
     (: max-tick-label-width (-> (Listof tick) Real))
     (define/private (max-tick-label-width ts)
       (apply max 0 (for/list : (Listof Real) ([t  (in-list ts)] #:when (pre-tick-major? t))
                      (send pd get-text-width (tick-label t)))))
-    
+
     (: max-x-tick-label-width Real)
     (: max-y-tick-label-width Real)
     (: max-z-tick-label-width Real)
@@ -819,7 +819,7 @@
     (define max-x-tick-label-height (max-tick-label-height x-ticks))
     (define max-y-tick-label-height (max-tick-label-height y-ticks))
     (define max-z-tick-label-height (max-tick-label-height z-ticks))
-    
+
     (: max-x-far-tick-label-width Real)
     (: max-y-far-tick-label-width Real)
     (: max-z-far-tick-label-width Real)
@@ -832,81 +832,81 @@
     (define max-x-far-tick-label-height (max-tick-label-height x-far-ticks))
     (define max-y-far-tick-label-height (max-tick-label-height y-far-ticks))
     (define max-z-far-tick-label-height (max-tick-label-height z-far-ticks))
-    
+
     (: max-tick-label-diag (-> (Vectorof Real) Real Real Real))
     (define/private (max-tick-label-diag axis-dc-dir max-tick-label-width max-tick-label-height)
       (match-define (vector dx dy) axis-dc-dir)
       (+ (* (abs dx) max-tick-label-width) (* (abs dy) max-tick-label-height)))
-    
+
     (: max-x-tick-label-diag (-> Real))
     (define (max-x-tick-label-diag)
       (if (and (plot-x-axis?) draw-x-tick-labels?)
           (max-tick-label-diag (y-axis-dir) max-x-tick-label-width max-x-tick-label-height)
           0))
-    
+
     (: max-y-tick-label-diag (-> Real))
     (define (max-y-tick-label-diag)
       (if (and (plot-y-axis?) draw-y-far-tick-labels?)
           (max-tick-label-diag (x-axis-dir) max-y-tick-label-width max-y-tick-label-height)
           0))
-    
+
     (: max-x-far-tick-label-diag (-> Real))
     (define (max-x-far-tick-label-diag)
       (if (and (plot-x-far-axis?) draw-x-far-tick-labels?)
           (max-tick-label-diag (y-axis-dir) max-x-far-tick-label-width max-x-far-tick-label-height)
           0))
-    
+
     (: max-y-far-tick-label-diag (-> Real))
     (define (max-y-far-tick-label-diag)
       (if (and (plot-y-far-axis?) draw-y-far-tick-labels?)
           (max-tick-label-diag (x-axis-dir) max-y-far-tick-label-width max-y-far-tick-label-height)
           0))
-    
+
     (: get-x-label-params (-> Label-Params))
     (define (get-x-label-params)
       (define v0 (norm->dc (flvector 0.0 x-axis-norm-y -0.5)))
       (define dist (+ max-x-tick-offset (max-x-tick-label-diag) half-char-height))
       (list (plot-x-label) (v+ v0 (v* (y-axis-dir) (if x-axis-y-min? (- dist) dist)))
             'top (- (if x-axis-y-min? 0 pi) (x-axis-angle))))
-    
+
     (: get-y-label-params (-> Label-Params))
     (define (get-y-label-params)
       (define v0 (norm->dc (flvector y-axis-norm-x 0.0 -0.5)))
       (define dist (+ max-y-tick-offset (max-y-tick-label-diag) half-char-height))
       (list (plot-y-label) (v+ v0 (v* (x-axis-dir) (if y-axis-x-min? (- dist) dist)))
             'top (- (if y-axis-x-min? pi 0) (y-axis-angle))))
-    
+
     (: get-z-label-params (-> Label-Params))
     (define (get-z-label-params)
       (list (plot-z-label) (v+ (plot->dc (vector z-axis-x z-axis-y z-max))
                                (vector 0 (- half-char-height)))
             'bottom-left 0))
-    
+
     (: get-x-far-label-params (-> Label-Params))
     (define (get-x-far-label-params)
       (define v0 (norm->dc (flvector 0.0 x-far-axis-norm-y -0.5)))
       (define dist (+ max-x-far-tick-offset (max-x-far-tick-label-diag) half-char-height))
       (list (plot-x-far-label) (v+ v0 (v* (y-axis-dir) (if x-axis-y-min? dist (- dist))))
             'bottom (- (if x-axis-y-min? 0 pi) (x-axis-angle))))
-    
+
     (: get-y-far-label-params (-> Label-Params))
     (define (get-y-far-label-params)
       (define v0 (norm->dc (flvector y-far-axis-norm-x 0.0 -0.5)))
       (define dist (+ max-y-far-tick-offset (max-y-far-tick-label-diag) half-char-height))
       (list (plot-y-far-label) (v+ v0 (v* (x-axis-dir) (if y-axis-x-min? dist (- dist))))
             'bottom (- (if y-axis-x-min? pi 0) (y-axis-angle))))
-    
+
     (: get-z-far-label-params (-> Label-Params))
     (define (get-z-far-label-params)
       (list (plot-z-far-label) (v+ (plot->dc (vector z-far-axis-x z-far-axis-y z-max))
                                    (vector 0 (- half-char-height)))
             'bottom-right 0))
-    
+
     ;; -----------------------------------------------------------------------------------------------
     ;; All parameters
-    
+
     ;; Within each get-back-* or get-front-*, the parameters are ordered (roughly) back-to-front
-    
+
     (: get-back-label-params (-> (Listof Label-Params)))
     (define (get-back-label-params)
       (if (plot-decorations?)
@@ -915,7 +915,7 @@
                   (get-x-far-tick-label-params)
                   (get-y-far-tick-label-params))
           empty))
-    
+
     (: get-front-label-params (-> (Listof Label-Params)))
     (define (get-front-label-params)
       (if (plot-decorations?)
@@ -928,11 +928,11 @@
                   (if (plot-z-label) (list (get-z-label-params)) empty)
                   (if (plot-z-far-label) (list (get-z-far-label-params)) empty))
           empty))
-    
+
     (: get-all-label-params (-> (Listof Label-Params)))
     (define (get-all-label-params)
       (append (get-back-label-params) (get-front-label-params)))
-    
+
     (: get-back-tick-params (-> (Listof Tick-Params)))
     (define (get-back-tick-params)
       (if (plot-decorations?)
@@ -941,22 +941,22 @@
                   (if (plot-x-axis?) (get-x-tick-params) empty)
                   (if (plot-y-axis?) (get-y-tick-params) empty))
           empty))
-    
+
     (: get-front-tick-params (-> (Listof Tick-Params)))
     (define (get-front-tick-params)
       (if (plot-decorations?)
           (append (if (plot-z-axis?) (get-z-tick-params) empty)
                   (if (plot-z-far-axis?) (get-z-far-tick-params) empty))
           empty))
-    
+
     (: get-all-tick-params (-> (Listof Tick-Params)))
     (define (get-all-tick-params)
       (append (get-back-tick-params) (get-front-tick-params)))
-    
-    
+
+
     ;; -----------------------------------------------------------------------------------------------
     ;; Fixpoint margin computation
-    
+
     (: get-param-vs/set-view->dc! (-> Real Real Real Real (Listof (Vectorof Real))))
     (define/private (get-param-vs/set-view->dc! left right top bottom)
       ;(printf "margins: ~v ~v ~v ~v~n" left right top bottom)
@@ -973,7 +973,7 @@
                               (match-define (list _ v radius angle) p)
                               (send pd get-tick-endpoints v radius angle))
                             (get-all-tick-params)))))
-    
+
     (define: left : Real  0)
     (define: right : Real  0)
     (define: top : Real  0)
@@ -1006,7 +1006,7 @@
       (set! view->dc (make-view->dc left right top bottom)))
 
     (define/public (get-aspect-ratio) aspect-ratio)
-    
+
     (: area-x-min Real)
     (: area-x-max Real)
     (: area-y-min Real)
@@ -1015,13 +1015,13 @@
     (define area-x-max (- dc-x-size right))
     (define area-y-min top)
     (define area-y-max (- dc-y-size bottom))
-    
+
     (define/public (get-area-bounds-rect)
       (vector (ivl area-x-min area-x-max) (ivl area-y-min area-y-max)))
 
     ;; ===============================================================================================
     ;; Plot decoration
-    
+
     (: draw-title (-> Void))
     (define/private (draw-title)
       (define title (plot-title))
@@ -1029,7 +1029,7 @@
         (if (string? title)
             (send pd draw-text title (vector (* 1/2 dc-x-size) (ann 0 Real)) 'top)
             (send pd draw-pict title  (vector (* 1/2 dc-x-size) (ann 0 Real)) 'top 0))))
-    
+
     (: draw-back-axes (-> Void))
     (define/private (draw-back-axes)
       (when (plot-decorations?)
@@ -1050,7 +1050,7 @@
           (send pd draw-line
                 (norm->dc (flvector y-far-axis-norm-x -0.5 -0.5))
                 (norm->dc (flvector y-far-axis-norm-x 0.5 -0.5))))))
-    
+
     (: draw-front-axes (-> Void))
     (define/private (draw-front-axes)
       (when (plot-decorations?)
@@ -1063,14 +1063,14 @@
           (send pd draw-line
                 (norm->dc (flvector z-far-axis-norm-x z-far-axis-norm-y -0.5))
                 (norm->dc (flvector z-far-axis-norm-x z-far-axis-norm-y 0.5))))))
-    
+
     (: draw-ticks (-> (Listof Tick-Params) Void))
     (define/private (draw-ticks ps)
       (for ([p  (in-list ps)])
         (match-define (list major? v r angle) p)
         (if major? (send pd set-major-pen) (send pd set-minor-pen))
         (send pd draw-tick v r angle)))
-    
+
     (: draw-labels (-> (Listof Label-Params) Void))
     (define/private (draw-labels ps)
       (for ([p  (in-list ps)])
@@ -1079,23 +1079,23 @@
                (send pd draw-text label v anchor angle 0 #t))
               ((pict? label)
                (send pd draw-pict label v anchor 0)))))
-    
+
     ;; ===============================================================================================
     ;; Render list and its BSP representation
-    
-    (: structural-shapes (HashTable Integer (Listof BSP-Shape)))
+
+    (: structural-shapes (Immutable-HashTable Integer (Listof BSP-Shape)))
     ;; View-independent shapes, used to built initial BSP trees
     (define structural-shapes ((inst make-immutable-hash Integer (Listof BSP-Shape))))
-    
-    (: detail-shapes (HashTable Integer (Listof BSP-Shape)))
+
+    (: detail-shapes (Immutable-HashTable Integer (Listof BSP-Shape)))
     ;; View-dependent shapes, inserted into BSP trees before each refresh
     (define detail-shapes ((inst make-immutable-hash Integer (Listof BSP-Shape))))
-    
-    (: bsp-trees (U #f (HashTable Integer BSP-Tree)))
+
+    (: bsp-trees (Option (Immutable-HashTable Integer BSP-Tree)))
     ;; Structural shapes partitioned in BSP trees, indexed by drawing layer
     ;; #f means not in sync with structural-shapes
     (define bsp-trees #f)
-    
+
     (: add-shape! (-> Integer BSP-Shape Void))
     (define/private (add-shape! layer s)
       (cond [(structural-shape? s)
@@ -1105,38 +1105,38 @@
             [else
              (define ss detail-shapes)
              (set! detail-shapes (hash-set ss layer (cons s (hash-ref ss layer (λ () empty)))))]))
-    
+
     (: add-shapes! (-> Integer (Listof BSP-Shape) Void))
     (define/private (add-shapes! layer ss)
       (for ([s  (in-list ss)])
         (add-shape! layer s)))
-    
+
     (: clear-shapes! (-> Void))
     (define/private (clear-shapes!)
       (set! structural-shapes ((inst make-immutable-hash Integer (Listof BSP-Shape))))
       (set! detail-shapes ((inst make-immutable-hash Integer (Listof BSP-Shape))))
       (set! bsp-trees #f))
-    
+
     (define/public (get-render-tasks)
       (define bsp-trees (sync-bsp-trees))
       (render-tasks structural-shapes detail-shapes bsp-trees))
-    
+
     (define/public (set-render-tasks tasks)
       (match-define (render-tasks sts dts bsps) tasks)
       (set! structural-shapes sts)
       (set! detail-shapes dts)
       (set! bsp-trees bsps))
-    
-    (: sync-bsp-trees (-> (HashTable Integer BSP-Tree)))
+
+    (: sync-bsp-trees (-> (Immutable-HashTable Integer BSP-Tree)))
     (define/private (sync-bsp-trees)
       (define bsp-trees-val bsp-trees)
       (cond
-        [bsp-trees-val  bsp-trees-val]
+        [bsp-trees-val bsp-trees-val]
         [else
          (define bsp-trees-val (build-bsp-trees structural-shapes))
          (set! bsp-trees bsp-trees-val)
          bsp-trees-val]))
-    
+
     (: adjust-detail-shapes (-> (Listof BSP-Shape) (Listof BSP-Shape)))
     (define/private (adjust-detail-shapes ss)
       (define d (view->norm view-dir))
@@ -1145,7 +1145,7 @@
       (define dz (flvector-ref d 2))
       (define area-size (fl (min (- area-x-max area-x-min)
                                  (- area-y-max area-y-min))))
-      
+
       (for/list : (Listof BSP-Shape) ([s  (in-list ss)])
         (match s
           [(points data vs)
@@ -1158,7 +1158,7 @@
           [(line data v1 v2)
            ;; Bring line forward by about half its apparent thickness
            (define frac (* 0.5 (/ pen-width area-size)))
-           (line data 
+           (line data
                  (flvector (+ (flvector-ref v1 0) (* dx frac))
                            (+ (flvector-ref v1 1) (* dy frac))
                            (+ (flvector-ref v1 2) (* dz frac)))
@@ -1173,54 +1173,54 @@
                                    (+ (flvector-ref v 1) (* dy frac))
                                    (+ (flvector-ref v 2) (* dz frac)))))]
           [_  s])))
-    
+
     (: draw-all-shapes (-> Void))
     (define/private (draw-all-shapes)
       (define bsp-trees (sync-bsp-trees))
-      
+
       (define adj-detail-shapes
-        (for/hasheq : (HashTable Integer (Listof BSP-Shape)) ([(layer ss)  (in-hash detail-shapes)])
+        (for/hasheq : (Immutable-HashTable Integer (Listof BSP-Shape)) ([(layer ss)  (in-hash detail-shapes)])
           (values layer (adjust-detail-shapes ss))))
-      
+
       (define all-shapes (walk-bsp-trees bsp-trees (view->norm view-dir) adj-detail-shapes))
-      
+
       (for* ([layer  (in-list (sort (hash-keys all-shapes) >))]
              [s      (in-list (hash-ref all-shapes layer))])
         (draw-shape s)))
-    
+
     ;; ===============================================================================================
     ;; Lighting
-    
+
     (: light FlVector)
     ;; Light position, in normalized view coordinates: 5 units up, ~3 units back and to the left
     ;; (simulates non-noon daylight conditions)
     (define light (m3-apply rotate-rho-matrix (flvector (- -0.5 2.0)
                                                         (- -0.5 2.0)
                                                         (+ 0.5 5.0))))
-    
+
     ;; Do lighting only by direction so we can precalculate light-dir and half-dir
     ;; Conceptually, the viewer and light are at infinity
-    
+
     (: light-dir FlVector)
     ;; Light direction
     (define light-dir (vector->flvector (vnormalize (flv3->v light))))
-    
+
     (: view-dir FlVector)
     ;; View direction, in normalized view coordinates
     (define view-dir (flvector 0.0 -1.0 0.0))
-    
+
     (: half-dir FlVector)
     ;; Blinn-Phong "half angle" direction
     (define half-dir
       (vector->flvector (vnormalize (v* (v+ (flv3->v light-dir) (flv3->v view-dir)) 0.5))))
-    
+
     (: diffuse-light? Boolean)
     (: specular-light? Boolean)
     (: ambient-light Flonum)
     (define diffuse-light? (plot3d-diffuse-light?))
     (define specular-light? (plot3d-specular-light?))
     (define ambient-light (fl (plot3d-ambient-light)))
-    
+
     (: get-light-values (-> FlVector (Values Flonum Flonum)))
     (define/private (get-light-values normal)
       (cond
@@ -1238,17 +1238,17 @@
          ;; Blend ambient light with diffuse light, return specular as it is
          ;; As ambient-light -> 1.0, contribution of diffuse -> 0.0
          (values (fl+ ambient-light (fl* (fl- 1.0 ambient-light) diff)) spec)]))
-    
+
     (: illuminate (-> (List Real Real Real) Real Real (List Real Real Real)))
     (define/private (illuminate c diff spec)
       (match-define (list r g b) c)
       (list (+ (* r diff) spec)
             (+ (* g diff) spec)
             (+ (* b diff) spec)))
-    
+
     ;; ===============================================================================================
     ;; Drawing
-    
+
     (: draw-polygon (-> poly Void))
     (define/private (draw-polygon s)
       (match-define (poly (poly-data alpha center
@@ -1283,21 +1283,21 @@
                         [v2  (in-list vs)]
                         [l   (in-list ls)])
                     (when l (send pd draw-line v1 v2)))]))]))
-    
+
     (: draw-line (-> line Void))
     (define/private (draw-line s)
       (match-define (line (line-data alpha pen-color pen-width pen-style) v1 v2) s)
       (send pd set-alpha alpha)
       (send pd set-pen pen-color pen-width pen-style)
       (send pd draw-line (norm->dc v1) (norm->dc v2)))
-    
+
     (: draw-lines (-> lines Void))
     (define/private (draw-lines s)
       (match-define (lines (line-data alpha pen-color pen-width pen-style) vs) s)
       (send pd set-alpha alpha)
       (send pd set-pen pen-color pen-width pen-style)
       (send pd draw-lines (map (λ ([v : FlVector]) (norm->dc v)) vs)))
-    
+
     (: draw-glyph (-> glyph-data (Listof FlVector) Void))
     (define/private (draw-glyph data vs)
       (match-define (glyph-data alpha symbol size
@@ -1308,7 +1308,7 @@
       (send pd set-pen pen-color pen-width pen-style)
       (send pd set-brush brush-color brush-style)
       (send pd draw-glyphs (map (λ ([v : FlVector]) (norm->dc v)) vs) symbol size))
-    
+
     (: draw-text (-> text-data (Listof FlVector) Void))
     (define/private (draw-text data vs)
       (match-define (text-data alpha anchor angle dist str font-size font-family color outline?) data)
@@ -1317,7 +1317,7 @@
       (send pd set-text-foreground color)
       (for ([v  (in-list vs)])
         (send pd draw-text str (norm->dc v) anchor angle dist outline?)))
-    
+
     (: draw-arrow (-> arrow-data Void))
     (define/private (draw-arrow data)
       (match-define (arrow-data alpha v1 v2 outline-color pen-color pen-width pen-style size-or-scale angle) data)
@@ -1329,14 +1329,14 @@
         (send pd set-pen pen-color pen-width pen-style)
         (send pd set-arrow-head size-or-scale angle)
         (send pd draw-arrow v1 v2)))
-    
+
     (: draw-points (-> points Void))
     (define/private (draw-points s)
       (match-define (points data vs) s)
       (cond [(glyph-data? data)  (draw-glyph data vs)]
             [(text-data? data)   (draw-text data vs)]
             [(arrow-data? data)  (draw-arrow data)]))
-    
+
     (: draw-shape (-> BSP-Shape Void))
     (define/private (draw-shape s)
       (cond [(poly? s)    (draw-polygon s)]
@@ -1344,10 +1344,10 @@
             [(lines? s)   (draw-lines s)]
             [(points? s)  (draw-points s)]
             [else  (raise-argument-error 'draw-shape "known shape" s)]))
-    
+
     ;; ===============================================================================================
     ;; Public drawing control (used by plot3d/dc)
-    
+
     (define/public (start-plot)
       (send pd reset-drawing-params)
       (send pd clear)
@@ -1361,11 +1361,11 @@
             (vector (ivl (+ 1/2 (- area-x-min (plot-line-width))) (+ area-x-max (plot-line-width)))
                     (ivl (+ 1/2 (- area-y-min (plot-line-width))) (+ area-y-max (plot-line-width)))))
       (clear-shapes!))
-    
+
     (define/public (start-renderer rend-bounds-rect)
       (reset-drawing-params)
       (put-clip-rect rend-bounds-rect))
-    
+
     (define/public (end-renderers)
       (clear-clip-rect)
       (draw-all-shapes)
@@ -1375,7 +1375,7 @@
       (draw-labels (get-front-label-params))
       (when (and (not (empty? legend)) (inside-anchor? (plot-legend-anchor)))
         (draw-legend legend)))
-    
+
     (define/public (draw-legend legend-entries)
       (define outside? (outside-anchor? (plot-legend-anchor)))
       (define gap-size (+ (pen-gap) (if outside? 0 tick-radius)))
@@ -1387,40 +1387,40 @@
       (send pd draw-legend legend-entries
             (vector (ivl (+ x-min gap-size) (- x-max gap-size))
                     (ivl (+ y-min gap-size) (- y-max gap-size)))))
-    
+
     (define/public (end-plot)
       (send pd restore-drawing-params))
-    
+
     ;; ===============================================================================================
     ;; Public drawing interface (used by renderers)
-    
+
     ;; Drawing parameters
-    
+
     (: alpha Nonnegative-Real)
     (define alpha 1)
-    
+
     (: pen-color (List Real Real Real))
     (: pen-width Nonnegative-Real)
     (: pen-style Plot-Pen-Style-Sym)
     (define pen-color '(0 0 0))
     (define pen-width 1)
     (define pen-style 'solid)
-    
+
     (: brush-color (List Real Real Real))
     (: brush-style Plot-Brush-Style-Sym)
     (define brush-color '(255 255 255))
     (define brush-style 'solid)
-    
+
     (: background-color (List Real Real Real))
     (define background-color '(255 255 255))
-    
+
     (: font-size Nonnegative-Real)
     (: font-face (U #f String))
     (: font-family Font-Family)
     (define font-size 11)
     (define font-face #f)
     (define font-family 'roman)
-    
+
     (: text-foreground (List Real Real Real))
     (define text-foreground '(0 0 0))
 
@@ -1429,41 +1429,41 @@
     (define pa-arrow-head-size-or-scale (arrow-head-size-or-scale))
     (define pa-arrow-head-angle (arrow-head-angle))
 
-    
+
     ;; Drawing parameter accessors
-    
+
     (define/public (put-alpha a) (set! alpha a))
-    
+
     (define/public (put-pen color width style)
       (set! pen-color (->pen-color color))
       (set! pen-width width)
       (set! pen-style (->pen-style style)))
-    
+
     (define/public (put-major-pen [style 'solid])
       (put-pen (plot-foreground) (plot-line-width) style))
-    
+
     (define/public (put-minor-pen [style 'solid])
       (put-pen (plot-foreground) (* 1/2 (plot-line-width)) style))
-    
+
     (define/public (put-brush color style)
       (set! brush-color (->brush-color color))
       (set! brush-style (->brush-style style)))
-    
+
     (define/public (put-background color)
       (set! background-color (->brush-color color)))
-    
+
     (define/public (put-font-size size) (set! font-size size))
     (define/public (put-font-face face) (set! font-face face))
     (define/public (put-font-family family) (set! font-family family))
-    
+
     (define/public (put-font-attribs size face family)
       (put-font-size size)
       (put-font-face face)
       (put-font-family family))
-    
+
     (define/public (put-text-foreground c)
       (set! text-foreground (->pen-color c)))
-    
+
     (define/public (put-arrow-head size-or-scale angle)
       (set! pa-arrow-head-size-or-scale size-or-scale)
       (set! pa-arrow-head-angle angle))
@@ -1475,9 +1475,9 @@
       (put-background (plot-background))
       (put-font-attribs (plot-font-size) (plot-font-face) (plot-font-family))
       (put-text-foreground (plot-foreground)))
-    
+
     ;; Drawing shapes
-    
+
     (define/public (put-line v1 v2)
       (let ([v1  (exact-vector3d v1)]
             [v2  (exact-vector3d v2)])
@@ -1499,7 +1499,7 @@
                      (add-shape! plot3d-area-layer
                                  (lines (line-data alpha pen-color pen-width pen-style)
                                         (map (λ ([v : (Vectorof Real)]) (plot->norm v)) vs)))]))))))
-    
+
     (define/public (put-lines vs)
       (for ([vs  (in-list (exact-vector3d-sublists vs))])
         (let ([vss  (if clipping?
@@ -1519,7 +1519,7 @@
                      (add-shape! plot3d-area-layer
                                  (lines (line-data alpha pen-color pen-width pen-style)
                                         (map (λ ([v : (Vectorof Real)]) (plot->norm v)) vs)))))]))))
-    
+
     (define/public (put-polygon vs [face 'both] [ls (make-list (length vs) #t)])
       (let-values ([(vs ls)  (exact-polygon3d vs ls)])
         (unless (empty? vs)
@@ -1542,7 +1542,7 @@
                                            pen-color pen-width pen-style
                                            brush-color brush-style face)
                                 norm-vs ls normal)))))))
-    
+
     (define/public (put-rect r)
       (let ([r  (if (rect-rational? r) (rect-meet r bounds-rect) r)])
         (when (rect-rational? r)
@@ -1565,7 +1565,7 @@
             (define z-mid (* 0.5 (+ z-max z-min)))
             ;; Faces are a list of center, normal, then vertices
             (define faces
-              (list 
+              (list
                ;; Bottom (z-min) face
                (list (flvector x-mid y-mid z-min) (flvector 0.0 0.0 -1.0)
                      (flvector x-min y-min z-min) (flvector x-max y-min z-min)
@@ -1598,7 +1598,7 @@
                                            pen-color pen-width pen-style
                                            brush-color brush-style 'front)
                                 vs ls normal)))))))
-    
+
     (define/public (put-text str v [anchor 'center] [angle 0] [dist 0] [outline? #f]
                              [layer plot3d-area-layer])
       (let ([v  (exact-vector3d v)])
@@ -1606,7 +1606,7 @@
           (add-shape! layer (points (text-data alpha anchor angle dist str
                                                font-size font-family text-foreground outline?)
                                     (list (plot->norm v)))))))
-    
+
     (define/public (put-glyphs vs symbol size [layer plot3d-area-layer])
       (let ([vs  (filter (λ ([v : (U #f (Vectorof Real))]) (and v (in-bounds? v)))
                          (map exact-vector3d vs))])
@@ -1617,7 +1617,7 @@
                                     (map (λ ([v : (U #f (Vectorof Real))])
                                            (plot->norm (assert v values)))
                                          vs))))))
-    
+
     (define/public (put-arrow v1 v2 [draw-outside? #f])
       (let ([v1  (exact-vector3d v1)]
             [v2  (exact-vector3d v2)])