🐛 Avoid extra render calls on page initialization with wasm render (#5701)

frontend/src/app/main/ui/workspace/viewport_wasm.cljs

@@ -133,6 +133,7 @@
         frame-hover       (mf/use-state nil)
         active-frames     (mf/use-state #{})
         canvas-init?      (mf/use-state false)
+        initialized?      (mf/use-state false)
 
         ;; REFS
         [viewport-ref
@@ -293,23 +294,28 @@
         (wasm.api/resize-viewbox (:width vport) (:height vport))))
 
     (mf/with-effect [@canvas-init?  base-objects]
-      (when @canvas-init?
+      (when (and @canvas-init? @initialized?)
         (wasm.api/set-objects base-objects)))
 
     (mf/with-effect [@canvas-init? preview-blend]
       (when (and @canvas-init? preview-blend)
         (wasm.api/request-render "with-effect")))
 
-    (mf/with-effect [@canvas-init? vbox]
-      (when @canvas-init?
+    (mf/with-effect [@canvas-init? zoom vbox background]
+      (when (and @canvas-init? (not @initialized?))
+        (wasm.api/initialize base-objects zoom vbox background)
+        (reset! initialized? true)))
+
+    (mf/with-effect [vbox]
+      (when (and @canvas-init? initialized?)
         (wasm.api/set-view-zoom zoom vbox)))
 
-    (mf/with-effect [@canvas-init? vbox]
-      (when @canvas-init?
+    (mf/with-effect [vbox]
+      (when (and @canvas-init? initialized?)
         (wasm.api/set-view-box zoom vbox)))
 
-    (mf/with-effect [@canvas-init? background]
-      (when @canvas-init?
+    (mf/with-effect [background]
+      (when (and @canvas-init? initialized?)
         (wasm.api/set-canvas-background background)))
 
     (hooks/setup-dom-events zoom disable-paste in-viewport? read-only? drawing-tool drawing-path?)

frontend/src/app/render_wasm/api.cljs

@@ -573,6 +573,19 @@
            (rx/reduce conj [])
            (rx/subs! request-render)))))
 
+(defn set-canvas-background
+  [background]
+  (let [rgba (rgba-from-hex background 1)]
+    (h/call internal-module "_set_canvas_background" rgba)
+    (request-render "set-canvas-background")))
+
+(defn initialize
+  [base-objects zoom vbox background]
+  (let [rgba (rgba-from-hex background 1)]
+    (h/call internal-module "_set_canvas_background" rgba)
+    (h/call internal-module "_set_view" zoom (- (:x vbox)) (- (:y vbox)))
+    (set-objects base-objects)))
+
 (def ^:private canvas-options
   #js {:antialias false
        :depth true
@@ -610,11 +623,6 @@
   ;; TODO: perform corresponding cleaning
   (h/call internal-module "_clean_up"))
 
-(defn set-canvas-background
-  [background]
-  (let [rgba (rgba-from-hex background 1)]
-    (h/call internal-module "_set_canvas_background" rgba)))
-
 (defonce module
   (delay
     (if (exists? js/dynamicImport)

render-wasm/src/state.rs

@@ -67,6 +67,5 @@ impl<'a> State<'a> {
 
     pub fn set_background_color(&mut self, color: skia::Color) {
         self.render_state.set_background_color(color);
-        self.render_all(true);
     }
 }