transmit current-poly-target to parallel rendering place

pollen/private/ts.rktd

@@ -1 +1 @@
-1556202286
+1556304028

pollen/render.rkt

@@ -59,9 +59,11 @@
        (for/list ([i (in-range (processor-count))])
                  (place ch
                         (let loop ()
+                          (match-define (cons path poly-target) (place-channel-get ch))
                           (define result
                             (with-handlers ([exn:fail? (λ (e) #false)])
-                      (render-from-source-or-output-path (place-channel-get ch))
+                              (parameterize ([current-poly-target poly-target])
+                                (render-from-source-or-output-path path))
                               #true))
                           (place-channel-put ch result)
                           (loop)))))
@@ -80,7 +82,7 @@
                 [(wp wpidx) (in-indexed worker-places)])
                (message (format "rendering parallel on core ~a /~a" (add1 wpidx)
                                 (find-relative-path (current-project-root) (->source-path path))))
-         (place-channel-put wp path))
+               (place-channel-put wp (cons path (current-poly-target))))
           (for ([path (in-list path-group)]
                 [(wp wpidx) (in-indexed worker-places)])
                (message (format "rendered parallel on core ~a /~a" (add1 wpidx)