User-manual.md

@@ -11,7 +11,7 @@ The adaptive grid means that the grid adapts the number of subdivision depending
 
 ### Free mode
 
-In snap mode, scattering vectors position is not restrained to a set of points. However, scattering vector norm can be fixed in the scattering parameters panel (Panels > Show Scattering Parameters). When a norm is fixed, scattering vectors can only move in positions that respect theses constrains.
+In snap mode, scattering vectors position is not restrained to a set of points. However, scattering vector norm can be fixed in the scattering parameters panel (Panels > Show Scattering Parameters). When a norm is fixed, scattering vectors can only move in positions that respect theses constraints.
 
 Define scan trajectories
 ---
@@ -20,6 +20,8 @@ To create a new trajectory, right click on the sphere pointed by the Q vector (t
 
 ![trajectoryselect](/uploads/7f7928ffb31f2e00c10e74309315b711/trajectoryselect.png)
 
+When the trajectory is set, a purple line starting from the start point of the trajectory to the end point of the trajectory will appear. The white spheres in it represent the point to be scanned at each step. Steps can be changed using the trajectory panel (Panels > Show trajectory).
+
 The new trajectory now appear in the trajectory panel (Panels > Show Trajectory). Trajectories can either be modified by clicking on a given trajectory, renamed or deleted. 
 In the same way, you can define multiple trajectories by following the same steps.