Merge pull request #5235 from penpot/azazeln28-handle-webgl-context

🎉 Handle WebGL Context

frontend/src/app/main/data/render_wasm.cljs

@@ -0,0 +1,17 @@
+(ns app.main.data.render-wasm
+  (:require
+   [potok.v2.core :as ptk]))
+
+(defn context-lost
+  []
+  (ptk/reify ::context-lost
+    ptk/UpdateEvent
+    (update [_ state]
+      (update state :render-state #(assoc % :lost true)))))
+
+(defn context-restored
+  []
+  (ptk/reify ::context-restored
+    ptk/UpdateEvent
+    (update [_ state]
+      (update state :render-state #(dissoc % :lost)))))

frontend/src/app/main/refs.cljs

@@ -116,6 +116,12 @@
 
 ;; ---- Workspace refs
 
+(def render-state
+  (l/derived :render-state st/state))
+
+(def render-context-lost?
+  (l/derived :lost render-state))
+
 (def workspace-local
   (l/derived :workspace-local st/state))
 

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

@@ -111,6 +111,8 @@
         modifiers         (mf/deref refs/workspace-modifiers)
         text-modifiers    (mf/deref refs/workspace-text-modifier)
 
+        render-context-lost? (mf/deref refs/render-context-lost?)
+
         objects-modified  (mf/with-memo [base-objects text-modifiers modifiers]
                             (apply-modifiers-to-selected selected base-objects text-modifiers modifiers))
 
@@ -175,6 +177,8 @@
 
         mode-inspect?       (= options-mode :inspect)
 
+        on-render-restore-context #(.reload js/location)
+
         on-click          (actions/on-click hover selected edition drawing-path? drawing-tool space? selrect z?)
         on-context-menu   (actions/on-context-menu hover hover-ids read-only?)
         on-double-click   (actions/on-double-click hover hover-ids hover-top-frame-id drawing-path? base-objects edition drawing-tool z? read-only?)
@@ -277,9 +281,9 @@
              (p/fmap (fn [ready?]
                        (when ready?
                          (reset! canvas-init? true)
-                         (render.wasm/assign-canvas canvas)))))
+                         (render.wasm/setup-canvas canvas)))))
         (fn []
-          (render.wasm/clear-canvas))))
+          (render.wasm/dispose-canvas canvas))))
 
     (mf/with-effect [objects-modified canvas-init?]
       (when @canvas-init?
@@ -635,4 +639,11 @@
          {:objects base-objects
           :zoom zoom
           :vbox vbox
-          :bottom-padding (when palete-size (+ palete-size 8))}]]]]]))
+          :bottom-padding (when palete-size (+ palete-size 8))}]]]]
+
+     (when render-context-lost?
+       [:div {:id "context-lost" :class (stl/css :context-lost)}
+        [:h1 "GL Error Screen"]
+        [:button
+         {:on-click on-render-restore-context}
+         "Restore context"]])]))

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

@@ -35,3 +35,13 @@
   right: 0;
   z-index: 10;
 }
+
+.context-lost {
+  position: fixed;
+  inset: 0;
+  z-index: 100;
+  background-color: rgba(0, 0, 0, 0.5);
+  display: grid;
+  place-items: center;
+  cursor: default;
+}

frontend/src/app/render_wasm.cljs

@@ -11,6 +11,10 @@
    [app.common.files.helpers :as cfh]
    [app.common.types.shape.impl]
    [app.config :as cf]
+   [app.main.data.render-wasm :as drw]
+   [app.main.store :as st]
+   [app.util.debug :as dbg]
+   [app.util.dom :as dom]
    [promesa.core :as p]))
 
 (def enabled?
@@ -82,29 +86,67 @@
        :stencil true
        :alpha true})
 
-(defn clear-canvas
-  []
-  ;; TODO: perform corresponding cleaning
-  )
+(defn init-skia
+  [canvas]
+  (let [init-fn (unchecked-get internal-module "_init")
+        state   (init-fn (.-width ^js canvas)
+                         (.-height ^js canvas))]
+    (set! internal-gpu-state state)))
 
-(defn assign-canvas
+;; NOTE: This function can be called externally
+;; by the button in the context lost component (shown
+;; in viewport-wasm) or called internally by
+;; on-webgl-context
+(defn restore-canvas
+  [canvas]
+  (st/emit! (drw/context-restored))
+  ;; We need to reinitialize skia when the
+  ;; context is restored.
+  (init-skia canvas))
+
+;; Handles both events: webglcontextlost and
+;; webglcontextrestored
+(defn on-webgl-context
+  [event]
+  (dom/prevent-default event)
+  (if (= (.-type event) "webglcontextlost")
+    (st/emit! (drw/context-lost))
+    (restore-canvas (dom/get-target event))))
+
+(defn dispose-canvas
+  [canvas]
+  ;; TODO: perform corresponding cleaning
+  (.removeEventListener canvas "webglcontextlost" on-webgl-context)
+  (.removeEventListener canvas "webglcontextrestored" on-webgl-context))
+
+(defn init-debug-webgl-context-state
+  [context]
+  (let [context-extension (.getExtension ^js context "WEBGL_lose_context")
+        info-extension (.getExtension ^js context "WEBGL_debug_renderer_info")]
+    (set! (.-penpotGL js/window) #js {:context context-extension
+                                      :renderer info-extension})
+    (js/console.log "WEBGL_lose_context" context-extension)
+    (js/console.log "WEBGL_debug_renderer_info" info-extension)))
+
+(defn setup-canvas
   [canvas]
   (let [gl      (unchecked-get internal-module "GL")
-        init-fn (unchecked-get internal-module "_init")
-
         context (.getContext ^js canvas "webgl2" canvas-options)
 
         ;; Register the context with emscripten
         handle  (.registerContext ^js gl context #js {"majorVersion" 2})
-        _       (.makeContextCurrent ^js gl handle)
+        _       (.makeContextCurrent ^js gl handle)]
 
-        ;; Initialize Skia
-        state   (init-fn (.-width ^js canvas)
-                         (.-height ^js canvas))]
+    (when (dbg/enabled? :gl-context)
+      (init-debug-webgl-context-state context))
+
+    (.addEventListener canvas "webglcontextlost" on-webgl-context)
+    (.addEventListener canvas "webglcontextrestored" on-webgl-context)
 
     (set! (.-width canvas) (.-clientWidth ^js canvas))
     (set! (.-height canvas) (.-clientHeight ^js canvas))
-    (set! internal-gpu-state state)))
+
+    (init-skia canvas)))
 
 (defonce module
   (->> (js/dynamicImport "/js/render_wasm.js")

frontend/src/app/util/debug.cljs

@@ -89,7 +89,10 @@
     :display-touched
 
     ;; Show some visual indicators for bool shape
-    :bool-shapes})
+    :bool-shapes
+
+    ;; Show some information about the WebGL context.
+    :gl-context})
 
 (defn enable!
   [option]

render-wasm/Cargo.lock

@@ -96,6 +96,22 @@ version = "1.13.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "60b1af1c220855b6ceac025d3f6ecdd2b7c4894bfe9cd9bda4fbb4bc7c0d4cf0"
 
+[[package]]
+name = "emscripten-functions"
+version = "0.2.3"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "62c026cc030b24957ca45d9555f9fa241d6b3a01d725cd98a25924de249b840a"
+dependencies = [
+ "cc",
+ "emscripten-functions-sys",
+]
+
+[[package]]
+name = "emscripten-functions-sys"
+version = "4.1.67"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "65715a5f07b03636d7cd5508a45d1b62486840cb7d91a66564a73f1d7aa70b79"
+
 [[package]]
 name = "equivalent"
 version = "1.0.1"
@@ -370,6 +386,8 @@ checksum = "2b15c43186be67a4fd63bee50d0303afffcef381492ebe2c5d87f324e1b8815c"
 name = "render"
 version = "0.1.0"
 dependencies = [
+ "emscripten-functions",
+ "emscripten-functions-sys",
  "gl",
  "skia-safe",
 ]

render-wasm/Cargo.toml

@@ -11,6 +11,8 @@ name = "render_wasm"
 path = "src/main.rs"
 
 [dependencies]
+emscripten-functions = "0.2.3"
+emscripten-functions-sys = "4.1.67"
 gl = "0.14.0"
 skia-safe = { version = "0.78.2", features = ["gl"] }