It is about symetrical triangles:
1. Add a volatility indicator of 300 bars.
2. Add a moving avarage of 200 closes.
If 1 goes very low adn 2 goes flat. It is a triangle - most probably. Unfortunatly, it does not filter out sideway market moves... not just triangles. But it is still ok.
Using a stop. We enter the market short or long and change if it was just false breakout.