gfx.blit requires four parameters...?

[Fabian]

The Lua API docs say of gfx.blit(source,scale,rotation) that "If three parameters are specified, copies the entirety of the source bitmap to gfx.x, gfx.y using current opacity and copy mode..." and more. Note the if. To me, this means that not all parameters are required. So I try: gfx.blit(src_img) and to my surprise I get an error saying Function 'blit' requires 4 parameters, 1 passed.

If I do gfx.blit(src_img, 1) I get a message saying almost the same thing: Function 'blit' requires 4 parameters, 2 passed

Only if I pass all three parameters gfx.blit(src_img, 1, 0) do I not get any error message.

So I guess the API docs and the error message should be updated. Right?

[schwa]

There are two help entries for gfx.blit. The one you are looking at describes the behavior with three parameters, the other one describes the behavior with more than three parameters. The 4th and 5th parameters are "srcx, srcy" so I think you are getting the "4 parameters" message because if you provide one, you have to provide both.

I do notice the documentation spells "entirity" wrong though

[Meo-Ada Mespotine]

Maybe it's better to rephrase the error-message to "...requires at least 3 parameters..."

[Fabian]

OK, this is a minor detail really, and maybe my post was a slight overreaction

Originally Posted by schwa

There are two help entries for gfx.blit. The one you are looking at describes the behavior with three parameters, the other one describes the behavior with more than three parameters. The 4th and 5th parameters are "srcx, srcy" so I think you are getting the "4 parameters" message because if you provide one, you have to provide both.

But, I'm not sure that I follow this... Yes, I read the notes for the simplified 3-parameter blit, and that's the one I use. The problem does not occur if I give srcx but not srcy, it occurs when I give only the src_img, and no scale, no rotation. That should not ask for 4 parameters, should it?

And if I have to give all three parameters, the docs should not say "If three parameters are specified". Or?

Originally Posted by schwa

I do notice the documentation spells "entirity" wrong though

Yeah, when quoting the spell-checker complained so I changed it But when updating that, maybe also the "if" should be removed.

[Justin]

Hmm yeah the two implementations of gfx_blit() can get combined, doing that.

[Meo-Ada Mespotine]

Originally Posted by Justin

Hmm yeah the two implementations of gfx_blit() can get combined, doing that.

Would it be possible to make rotation and scale optional? So

gfx.blit(1)

is equal to

gfx.blit(1, 1, 0)

?
I think that is probably the most used case for people who just want to quickly blit something.
Happens often to me, at least.

[Justin]

Originally Posted by Meo-Ada Mespotine

Would it be possible to make rotation and scale optional? So

gfx.blit(1)

is equal to

gfx.blit(1, 1, 0)

?
I think that is probably the most used case for people who just want to quickly blit something.
Happens often to me, at least.

Yeah, sure (though it wouldn't work with 6.44 and earlier)

[Meo-Ada Mespotine]

No problem for my usual usecases.

Maybe a note in the docs "6.44 and lower expect three parameters minimum" for scripts that need to be backwards-compatible should be enough, I think.

[Fabian]

Originally Posted by Meo-Ada Mespotine

Would it be possible to make rotation and scale optional? So

gfx.blit(1)

is equal to

gfx.blit(1, 1, 0)

?
I think that is probably the most used case for people who just want to quickly blit something.
Happens often to me, at least.

It is exactly the same here. This was what I stumbled on from the beginning, so would be very convenient.