Fix Viewer tests

Viewer/tests/validation/validation.js

@@ -51,27 +51,38 @@ function compare(renderData, referenceCanvas) {
     return (differencesCount * 100) / (width * height) > errorRatio;
 }
 
-function getRenderData(canvas, engine) {
+async function getRenderData(canvas, engine) {
     var width = canvas.width;
     var height = canvas.height;
 
-    var renderData = engine.readPixels(0, 0, width, height);
-    var numberOfChannelsByLine = width * 4;
-    var halfHeight = height / 2;
-
-    for (var i = 0; i < halfHeight; i++) {
-        for (var j = 0; j < numberOfChannelsByLine; j++) {
-            var currentCell = j + i * numberOfChannelsByLine;
-            var targetLine = height - i - 1;
-            var targetCell = j + targetLine * numberOfChannelsByLine;
-
-            var temp = renderData[currentCell];
-            renderData[currentCell] = renderData[targetCell];
-            renderData[targetCell] = temp;
-        }
-    }
+    return new Promise((resolve) => {
+        engine.onEndFrameObservable.addOnce(async () => {
+            var renderData = await engine.readPixels(0, 0, width, height);
+            var numberOfChannelsByLine = width * 4;
+            var halfHeight = height / 2;
+
+            for (var i = 0; i < halfHeight; i++) {
+                for (var j = 0; j < numberOfChannelsByLine; j++) {
+                    var currentCell = j + i * numberOfChannelsByLine;
+                    var targetLine = height - i - 1;
+                    var targetCell = j + targetLine * numberOfChannelsByLine;
+
+                    var temp = renderData[currentCell];
+                    renderData[currentCell] = renderData[targetCell];
+                    renderData[targetCell] = temp;
+                }
+            }
+            if (engine.isWebGPU) {
+                for (var i = 0; i < width * height * 4; i += 4) {
+                    var temp = renderData[i + 0];
+                    renderData[i + 0] = renderData[i + 2];
+                    renderData[i + 2] = temp;
+                }
+            }
 
-    return renderData;
+            resolve(renderData);
+        });
+    });
 }
 
 function saveRenderImage(data, canvas) {
@@ -106,9 +117,9 @@ function downloadDataUrlFromJavascript(filename, dataUrl) {
     document.body.removeChild(link);
 }
 
-function evaluate(test, resultCanvas, result, renderImage, index, waitRing, done) {
+async function evaluate(test, resultCanvas, result, renderImage, index, waitRing, done) {
     seed = 100000;
-    var renderData = getRenderData(currentViewer.canvas, currentViewer.engine);
+    var renderData = await getRenderData(currentViewer.canvas, currentViewer.engine);
     var testRes = true;
 
     // gl check