Add property to override the base color of model #82
Description
When loading a GLB file that has a default white or light-colored material, it's very difficult to see the model against a light or white application background. This results in a poor user experience due to low contrast.
While changing the app's background color is a possible workaround, it's not ideal as it forces a design change. The more flexible solution is to control the model's appearance directly.
It would be useful to have a new property in the widget that gives the ability to set or override the base color of the loaded model (modelColor or baseColorFactor, etc).
Not only would it solve this contrast problem, but allows a few new use cases (like user picking a color from palette to select color of product and/or being able to use a single GLB file representing multiple colors without new model files for each).
I believe this would involve exposing the pbrMetallicRoughness.baseColorFactor property of model-viewer.