Fix serializer

dist/preview release/serializers/babylon.glTF2Serializer.js

@@ -1906,7 +1906,7 @@ var BABYLON;
                             baseColorBuffer[offset] = metallicRoughness.baseColor.r * 255;
                             baseColorBuffer[offset + 1] = metallicRoughness.baseColor.g * 255;
                             baseColorBuffer[offset + 2] = metallicRoughness.baseColor.b * 255;
-                            baseColorBuffer[offset + 3] = resizedTextures.texture1.hasAlpha ? diffuseBuffer[offset + 3] : 255;
+                            baseColorBuffer[offset + 3] = resizedTextures.texture1.hasAlpha ? diffuseBuffer[offset + 3] * 255 : 255;
                             metallicRoughnessBuffer[offset] = 0;
                             metallicRoughnessBuffer[offset + 1] = metallicRoughness.roughness * 255;
                             metallicRoughnessBuffer[offset + 2] = metallicRoughness.metallic * 255;

dist/preview release/serializers/babylonjs.serializers.js

@@ -2067,7 +2067,7 @@ var BABYLON;
                             baseColorBuffer[offset] = metallicRoughness.baseColor.r * 255;
                             baseColorBuffer[offset + 1] = metallicRoughness.baseColor.g * 255;
                             baseColorBuffer[offset + 2] = metallicRoughness.baseColor.b * 255;
-                            baseColorBuffer[offset + 3] = resizedTextures.texture1.hasAlpha ? diffuseBuffer[offset + 3] : 255;
+                            baseColorBuffer[offset + 3] = resizedTextures.texture1.hasAlpha ? diffuseBuffer[offset + 3] * 255 : 255;
                             metallicRoughnessBuffer[offset] = 0;
                             metallicRoughnessBuffer[offset + 1] = metallicRoughness.roughness * 255;
                             metallicRoughnessBuffer[offset + 2] = metallicRoughness.metallic * 255;