Page 555 - Xara Designer Pro X17
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Animations        555


              Rotation

              Xara Designer Pro X calculates and generates the tween frames automatically by
              working out how to transform the shapes from one key frame to the next. But sometimes
              it's not possible to know exactly what type of rotation is required.
               Take this example. Suppose you tween
               from the first clock face to the second:







               You might expect it to rotate clockwise,
               but of course it could go counter
               clockwise:







               In fact there are other ways it could rotate. The above
               examples assume the hand rotates around one end, but you
               could tween from one state into the other by doing a straight
               line rotation of the center of the object, which would result in
               this:




              If you look closely, the hand rotates around its center rather than one end, and the center
              point moves in the straight line from one key frame to the next. By default, Xara Designer
              Pro X rotates objects this way.
              The Rotate command

              To force the rotation to be around any other point you can use a special keyword "rotate"
              appended to the front of the object name. Or you can use "rotate +" to force the rotation
              to go clockwise or "rotate -" to make it go counter clockwise.

              To take the simple two keyframes animation example shown on the previous page,
              where the hour hand needs to move from 12 o’clock to 8 o’clock. If you name the hand
              object "rotate + hand", you'll get an animation showing the clock’s hand moving
              clockwise. If you name it "rotate - hand", then the hand will rotate counter clockwise.
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