Bezier curve handles - precision modeling

Question

I encountered two problems while modeling with Bezier curves in Blender.

1. How do I equalize handle lengths? Basically I would like to make the handle A equal B in length, or make handle B equal to A.

2. How do I maintain constant angle while moving the handle? For example I would like to move the left handle to the left towards the X mark, but following the handle axis.

If it was a vertex on the edge, I would just use GG shortcut (with ALT), to move the vertex along the edge. This shortcut however doesn't work while moving curve handles.

Answer 1

Re. 1: To equalize the handle's lenght (without changing their angles) you may select the whole handle, press V-->Set Handle Type-->Free and enable the Snapping Tool (press the magnet icon and change its mode to Vertex). Rotate the shorter handle tip 180 degrees, then select the longer one and snap it to the shorter. Select the rotated one again and rotate it back to its place (input -180 while rotating).

Note: Sorry for an odd method to do it but nothing else comes to my mind right now:). The advantage of this method over Polosson's idea is you keep the angles of the handles, while when you change the handle type to Automatic you don't.

Re. 2: Change the Transform Orientation type to Normal and select the handle you want to move. Press G and input the desired axis (remember to press the button, which defines the axis twice to make a transformation along normal coordinates).

You may also just use scaling. Select desired handle tip and press S.

Answer 2

To equalize the handle tips length, you can set it to Automatic and just after that re-set it to Aligned. To do so, (in edit mode of course) select the handle, hit V, and choose the type you want. (You can also access this menu in Curve menu > Control Points > Set Handle Type.)

For your second question, you can use S after selecting one handle tip. This will move it towards, or away from center along the handle.