In this way, AE will use the Alpha channel information of the picture to draw the automatic trajectory. This is much more accurate and faster than drawing by hand, 1. If you feel that there are too many anchor points or the tracking is not careful, select the material in the menu, select Layer → Auto Tracking, and import the material with ALPHA channel into synthesis.
Display grid: Ctrl+': Align grid: Ctrl+Shift+' Display reference line: Ctrl+; : align with the reference line, ctrl+shift+; In the composition window, next to the mask, click that icon, and the third item will be ticked to display the grid, so AE will use the Alpha channel information of the picture to draw the automatic trajectory. This is much more accurate and faster than drawing by hand. If you feel that there are too many anchor points or the tracking is not careful, select the material in the menu, select Layer → Auto Tracking, and import the material with ALPHA channel into synthesis.