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CONTROLLING THE MOVEMENT OF A SPRITE


                 We can control a Sprite by using the sensing block.


                 SENSING BLOCK
                 The Sensing block gives an answer when asked a question. Sensing blocks are

                 colour-coded with a light-blue shade and are used to detect different sprites and
                 elements of a project including the edge of the stage. They control the movement of the
                 sprite in a better manner. The table given below outlines the code blocks that fit into this
                 category:




                           Blocks                                          Functions



                                                Checks if its sprite is touching the mouse-pointer, the edge,
                                                or another sprite. If the sprite is touching the  selected object,
                    touching mouse-pointer  ?
                                                the block returns a true value; if it is not, it returns ‘false’. It is
                                                used with an if-then block.

                                                Checks whether its sprite is touching a specified colour. If it
                     touching color  ?
                                                is, the block returns ‘true’. It is used with an if-then block.

                                                Makes an input box (with the specified text above it) and
                                                displays it at the bottom of the screen. The user can then
                   ask  What’s your name?  and wait
                                                enter  text  into  it  and  submit  it.  The input  is  stored  in  an
                                                Answer block after that.

                                                Holds the most recent text entered with the Ask () and Wait
                       answer
                                                block.
                                                Checks  if the specified  key  is  pressed.  If  the key  is  being
                   key  space    pressed?
                                                pressed, the block returns ‘true’; if it is not, it returns ‘false’.

                 Let us create a program and hear your cat meow.

                 Step  1   Click the Event button to show the Event blocks.                           when     clicked

                 Step  2   Click the Motion button to show the Motion blocks.                       move 100    steps

                 Step  3    Drag a Move 10 steps block to the code area and change the
                          value to 100.

                 Step  4   Click the Control Button to show the Control blocks.                       if       then

                 Step  5   Drag an if…then block to the code area.



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