Changing keyframe position in an expression?

[james-daugherty]

I have an animation of an object sliding back and forth with 3 key frames. The first is at 0, the second is a breakdown key that stays between the first and last, and the last I want to move with an expression to change the speed of the object.

this expression works;
keyframe -edit -index 2 -a -tc 30 -abd true "MP_5_Control.boltAnim";

but I would rather have something like
{
float $val = (1/MP_5_Control.emitAnim);
keyframe -edit -index 2 -a -tc $val -abd true "MP_5_Control.boltAnim";
}

where the MP_5_Control.emitAnim value is animated to change value of the time change in the keyframe command?

Like I said, the first expression works, but when I try to use the 2nd I get an Execution error. Does anyone have any ideas?

[james-daugherty]

I figured it out. One of the flags is -option, with "move", "insert", "over", and "segment over" as arguments. The default is move, but move won't go past a key that is already there. so when I was trying to change the rate from 1 to 15, the last key couldn't get past the middle and was throwing an error. I changed the -option to "over", and it works perfectly.

the final expression is:
keyframe -edit -index 2 -a -tc (30/MP_5_Control.emitAnim) -o over -abd true "MP_5_Control.boltAnim";

[joojaa]

Theres a tchnicaly better alternative too... Just make a expression for the time to be fed to your curve... If appropriate offfcourse.

Using mel in expressions is not realy the best of best things!