You know, I can sill remember the first time I started tinkering with Pinescript. As I had no prior programming experience, I learned by experimenting with other open-source scripts on TradingViews Marketplace. Tearing apart and combining interesting scripts to see what the output would be. @ChrisMoody was a huge source of inspiration for learning, and I wanted to thank him, as well as @TheLark for the concept behind this script.
The Trend Wave is based on @ChrisMoody's PPO-PercentileRank-Mkt-Tops-Bottoms, which also happens to be based on @TheLark's TheLark-Laguerre-PPO/.
Within my experimentation, I found that if I isolate the ppoT & ppoB variables and plot them calculated from extremely small decimals, you can get an extremely fast reacting, mirroring trend detector.
Within the script, you have the ability to plot the background colors based on trend to make it easier to see where crossovers occured, as well as a Mirror Input to view the mirrored version of the script.
In true TradingView spirit, the author of this script has published it open-source, so traders can understand and verify it. Cheers to the author! You may use it for free, but reuse of this code in a publication is governed by House Rules. You can favorite it to use it on a chart.