Hi, I'm a new user of Slic3r, and have noticed a problem with my builds when they have a gently sloping roof and a low density infill. The picture I've attached demonstrates the problem. Only the affected layer, and a few layers below it are displayed, for clarity.
The top layer in the picture contains the beginning of a gently sloping roof over part of the object. As you can see, it extends out over an empty cavity left by the sparse infill. As it builds, this part of the roof has nothing to support it and ends up being squirted down into the model, providing no support for the following layer.
I think the problem could be solved if the calculations were to take into account the locations of the infill walls below, and extend the first layer of each vertical shell out to meet them. Any extra material used would be buried invisibly inside the model, and would allow much more reliable builds without resorting to denser infill or extra shell layers.
I wonder if this is something available but hidden in the settings, or if it has been considered for development?