(Example Uses)
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==Example Uses==
 
==Example Uses==
 
*Often in games, the player controls a sprite and moves it around {{-}} the '''Change X by ()''' block (and the [[Change Y by () (block)|Change Y by ()]] block) are very common in this event.
 
*Often in games, the player controls a sprite and moves it around {{-}} the '''Change X by ()''' block (and the [[Change Y by () (block)|Change Y by ()]] block) are very common in this event.
 +
<scratchblocks>
 +
when gf clicked
 +
forever
 +
if <key [left v] pressed?>
 +
change x by (-5)
 +
end
 +
if <key [right v] pressed?>
 +
change x by (5)
 +
</scratchblocks>
 
*This block can also be used to move a sprite which creates a sine wave ''(see [[Trigonometry]])'' along the x axis. An example script of this situation is:
 
*This block can also be used to move a sprite which creates a sine wave ''(see [[Trigonometry]])'' along the x axis. An example script of this situation is:
 
<scratchblocks>
 
<scratchblocks>

Revision as of 20:17, 5 April 2014

Change X by ()
2.0 Change X by ().png
Category Motion
Type Stack
The Change X by () block is a Motion block and a Stack block. The block moves its sprite costume center's X position by the specified amount.

Example Uses

  • Often in games, the player controls a sprite and moves it around — the Change X by () block (and the Change Y by () block) are very common in this event.
when gf clicked
forever
if <key [left v] pressed?>
change x by (-5)
end
if <key [right v] pressed?>
change x by (5)
  • This block can also be used to move a sprite which creates a sine wave (see Trigonometry) along the x axis. An example script of this situation is:
when gf clicked
go to x (-240) y (([sin v] of (-240)) * (100)) //240 is the leftmost position of the stage
clear //clears a previously drawn wave, if it exists
pen down //draws the first point of the wave
repeat (480) //the width of the stage is 480 x coordinates
pen up //so the movement to the next position is not interfered with an unintended, out-of-place line
change x by (1) //the use of the block
set y to (([sin v] of (x position)) * (100)) //the result is multiplied by "100" to expand the amplitude for visual preference
pen down //creates the mark

Workaround

Main article: List of Block Workarounds

This block can be replicated with either of the following codes:

set x to ((x position) + (change))
go to x: ((x position) + (change)) y: (y position)

See Also