Designing Games with Game Maker - YoYo Games

number of images in the gif file is used. precise indicates whether precise
collision checking should be used. transparent indicates whether the image
is partially transparent. smooth indicates whether to smooth the edges.
preload indicates whether to preload the image into texture memory. xorig
and yorig indicate the position of the origin in the sprite. The function returns
the index of the new sprite that you can then use to draw it or to assign it to
the variable sprite_index of an instance. When an error occurs -1 is returned.
sprite_add_alpha(fname,imgnumb,precise,preload,xorig,yorig)
Adds the image stored in the file fname to the set of sprite resources, but this
time the file has an alpha channel to indicate transparency (as for example in
.png files). The arguments are the same as above (but two are missing as
they are not relevant in this case). When an error occurs -1 is returned.
sprite_replace(ind,fname,imgnumb,precise,transparent,smooth
,preload,xorig,yorig) Same as above but in this case the sprite with
index ind is replaced. The function returns whether it is successful.
sprite_replace_alpha(ind,fname,imgnumb,precise,preload,xori
g,yorig) Same as above but in this case the file has an alpha channel. The
function returns whether it is successful.
sprite_create_from_screen(x,y,w,h,precise,transparent,smoot
h,preload,xorig,yorig) Creates a sprite by copying the given area from
the screen. This makes it possible to create any sprite you want. Draw the
image on the screen using the drawing functions and next create a sprite from
it. (If you don't do this in the drawing event you can even do it in such a way
that it is not visible on the screen by not refreshing the screen.) The other
parameters are as above. The function returns the index of the new sprite. A
work of caution is required here. Even though we speak about the screen, it is
actually the drawing region that matters. The fact that there is a window on
the screen and that the image might be scaled in this window does not matter.
sprite_add_from_screen(ind,x,y,w,h) Adds an area of the screen as a
next subimage to the sprite with index ind.
sprite_create_from_surface(id,x,y,w,h,precise,transparent,s
mooth,preload,xorig,yorig) Creates a sprite by copying the given area
from the surface with the given id. This makes it possible to create any sprite
you want. Draw the image on the surface using the drawing functions and next
create a sprite from it. The function returns the index of the new sprite. Note
that alpha values are maintained in the sprite.