Просмотр кода страницы How to Go Off the Screen Edge

In the Scratch Player, [[sprite]]s are prevented from '''moving off the edge of the screen'''; if one tries to make a sprite do so by setting its x or y position to a very large positive or negative number, the sprite will be unable to move completely off of the [[Stage]].

However, it ''is'' possible to move a sprite completely off the screen by using a trick involving different costumes. There are multiple ways to pull off this trick, one of which is detailed below.

==Steps==
First of all, make two new costumes. Leave one of them blank, and fill the other one entirely using the [[Paint Editor#Paint Bucket 2|fill bucket]] (so that its width is 480 pixels and its height is 360 pixels). It can be any solid color. If other costumes are needed, create them; they are not subject to any requirements.

Next, create the following block (enable "run without screen refresh"):

<scratchblocks>
define go offscreen to x: (x) y: (y)
set [old costume v] to (costume [number v]) // back up costume
set [old size v] to (size) // back up size
switch costume to (blank costume v)
set size to ((1)/(0))% // or some similarly high number
switch costume to (completely filled costume v)
go to x: (x) y: (y)
set size to (old size)% // restore size
switch costume to (old costume) // restore costume
</scratchblocks>
To use it:
<scratchblocks>
when gf clicked
. . .
go offscreen to x: (wanted x) y: (wanted y) :: custom
. . .
</scratchblocks>

===Details===

This can be combined with [[Overriding the Costume Size Limit]] for use in scrollers.

A quick rundown on how the above definition works:

It first backs up the old costume ID and the old size for later.

It then uses [[Overriding the Costume Size Limit|a technique that can set a sprite's size to an arbitrarily large number.]] Basically, an empty costume's size can be set to any number between 100 and 54,000, and changing a sprite's costume does not change its size. This means that, by switching a sprite's costume to the empty costume, setting the size, and then switching back, a sprite can be set to practically any size that is needed.

Next, it exploits the different x and y position limits of different costumes and the fact that a sprite's costume changing will not change its x or y position. A larger costume can move farther off of the screen than a smaller costume, simply because it is larger; this fact can be magnified by using the set size block as shown previously.

Then it just restores the costume and size.

==See also==
* [[Overriding the Costume Size Limit]]

[[Category:Scripting Tutorials]]