I think I'm trying to do something that just is not possible, but I'm asking to confirm. I have a heatmap that I provide a custom colorscale for. However I have a need to supply a different (or multiple different) color scales for certain portions of the heatmap. Below is a picture explaining why.
In plot A, we have thresholds of -115 and -105. In a normal use-case these would be most of the range, but for this example, we have another set of thresholds much higher than that which spans most of the range. If the blue line crosses the yellow line, it should be colored yellow in Plot B and our colorscale approaches red the closer it gets to the red line.
In Plot B, we show where the blue line crosses our thresholds. The colorscale I'm providing the chart is for the set of lower thresholds. However the blue line never crosses the higher thresholds and is being colored incorrectly. So I think I would need to provide another colorscale for this portion of the graph. However, I don't think that is possible with Plotly at the moment. I'm looking for suggestions or ideas on what to do.