The problem here is that the bottom layer of the sky is drawn into the top layer, so it can only move one texel at a time. This looked decent in low resolutions, but it's very noticeable in higher ones. In a Quake port I found they solved this by actually separating the two layers, so they both have their own texture coordinates that can be scrolled separately.
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The problem here is that the bottom layer of the sky is drawn into the top layer, so it can only move one texel at a time. This looked decent in low resolutions, but it's very noticeable in higher ones. In a Quake port I found they solved this by actually separating the two layers, so they both have their own texture coordinates that can be scrolled separately.