Need help with lua? - LunaLua General Help

[Novarender]

I have multiple questions.

1. Is there any way to detect if a number is an integer?
2. I made a time limit-- how do I make it kill Mario when it reaches zero?
3. I was having trouble positioning printed text. Are its coordinates measured in pixels?
4. What are the dimensions of one printed character (in pixels or otherwise?)
5. Is there a way to make a loop stop? (e.g. exit loop)
6. Can you make a function loop every "x" ticks?
7. Can you create new npcs (adding more IDs) or other graphics?

1. Lua does not differentiate between integer, float, and other number types. Why specifically do you need to test this? There might be a better way.
2. Are you using an API to do so? (leveltimer.lua, etc.) If so, this is usually default. If you're using your own call player:kill();
3. Measured in pixels and using screen coordinates; top left is (0, 0), bottom right is (800, 600).
4. Depends on the character and its frame. You can use player.width and player.height to find these values.
5. Use a while loop or type break; on its own line inside a loop to break it.
6. You can call a function after a decreasing variable hits zero (and then reset that variable). Could probably use the eventu library but I wouldn't for this.
7. You can create new NPCs up to ID 300 in Beta3. In Beta4, we've added IDs up to 1000 iirc, a limit which can be extended easily, to add more NPCs. You can also replace current NPC graphics if you just need an existing AI. NPCs aren't easy to program

1: I just thought it might be useful. And I did find a better way to do what I was trying.
2: What do you mean by API? I just made my own timer. Is this like a pre-made one?
3: Ah. Thanks.
4: Well, I meant character as in a letter or number. They all seem to be around 16 pixels wide-- is this true?
5: Ok.
6: Ok.
7: Do you just have to create new NPCs and put them in the level folder/ game folder and you'll be able to use them?

The reason I asked a few of these is because I wanted to have a global tick count and make the timer decrease every 20 ticks. But the only way I could do this by basing it off the timer would be to divide the tick count by 20 and check if it is an integer.

Alternatively, I have a way to check for integers regardless:

Input number n.
Set c to zero.
Have c count up by one until it is greater than or equal to n.
If it is equal to n, n is an integer.
If it is greater than n, n is not an integer.

[Emral]

2: What do you mean by API? I just made my own timer. Is this like a pre-made one?

He means "library", which are scripts you can load using "local myLib = API.load("myLib") where myAPI is to be replaced with the library's name.

4: Well, I meant character as in a letter or number. They all seem to be around 16 pixels wide-- is this true?

16 pixels wide and 2 for spaces in between, yup.

7: Do you just have to create new NPCs and put them in the level folder/ game folder and you'll be able to use them?

You can basically make a Beta 3 npc do nothing by creating a folder as a subfolder of your level folder, called "NPCs", and putting a library in there which has the same name as the one you want to replace. Then just put the line "return {}" in there, and you got yourself an empty NPC slot. Then you can replace that slot with a NPC you have created.

But the only way I could do this by basing it off the timer would be to divide the tick count by 20 and check if it is an integer.

Couldn't you just use math.floor or math.ceil to round to an integer for drawing, but keep it a float internally?

[The0x539]

The reason I asked a few of these is because I wanted to have a global tick count and make the timer decrease every 20 ticks. But the only way I could do this by basing it off the timer would be to divide the tick count by 20 and check if it is an integer.

Alternatively, I have a way to check for integers regardless:

Input number n.
Set c to zero.
Have c count up by one until it is greater than or equal to n.
If it is equal to n, n is an integer.
If it is greater than n, n is not an integer.

Code: Select all

local lunatime = API.load("core/lunatime")
function onTick()
	if lunatime.tick() % 20 == 0 then
		--do stuff
	end
end

please avoid doing either of the things you just came up with
Modulo is a very useful mathematical operator. Division is fairly expensive, and that integer test is most likely extremely inefficient compared to checking whether a%1==0 (not to mention that that check isn't necessary when division itself isn't).

[Novarender]

7: Do you just have to create new NPCs and put them in the level folder/ game folder and you'll be able to use them?

You can basically make a Beta 3 npc do nothing by creating a folder as a subfolder of your level folder, called "NPCs", and putting a library in there which has the same name as the one you want to replace. Then just put the line "return {}" in there, and you got yourself an empty NPC slot. Then you can replace that slot with a NPC you have created.

That seems fairly complicated, and I just started LunaLua yesterday or so. Maybe in a while I'll come back to this...

But the only way I could do this by basing it off the timer would be to divide the tick count by 20 and check if it is an integer.

Couldn't you just use math.floor or math.ceil to round to an integer for drawing, but keep it a float internally?

I guess you're right. I actually did come up with something like that, but it was after I figured out the right way to do it.

Is it possible to force Mario to enter ANY state, such as his statue form? I might deprive the tanooki suit of its flight power and redesign it as a metal cap from Super Mario 64. If I can't do this, I might also just make a separate powerup entirely that changes Mario's properties.

Also, how can I use "loop while"? I tried it but I couldn't figure out how to format it properly.

One more thing: Is Player.speedX outdated? I tried to use it and it said it didn't exist.

The reason I asked a few of these is because I wanted to have a global tick count and make the timer decrease every 20 ticks. But the only way I could do this by basing it off the timer would be to divide the tick count by 20 and check if it is an integer.

Alternatively, I have a way to check for integers regardless:

Input number n.
Set c to zero.
Have c count up by one until it is greater than or equal to n.
If it is equal to n, n is an integer.
If it is greater than n, n is not an integer.

Code: Select all

local lunatime = API.load("core/lunatime")
function onTick()
	if lunatime.tick() % 20 == 0 then
		--do stuff
	end
end

please avoid doing either of the things you just came up with
Modulo is a very useful mathematical operator. Division is fairly expensive, and that integer test is most likely extremely inefficient compared to checking whether a%1==0 (not to mention that that check isn't necessary when division itself isn't).

I didn't understand some of that, and I don't need to yet, but I did just start LunaLua like yesterday so I haven't explored it much so far.

[The0x539]

The reason I asked a few of these is because I wanted to have a global tick count and make the timer decrease every 20 ticks. But the only way I could do this by basing it off the timer would be to divide the tick count by 20 and check if it is an integer.

Alternatively, I have a way to check for integers regardless:

Input number n.
Set c to zero.
Have c count up by one until it is greater than or equal to n.
If it is equal to n, n is an integer.
If it is greater than n, n is not an integer.

Code: Select all

local lunatime = API.load("core/lunatime")
function onTick()
	if lunatime.tick() % 20 == 0 then
		--do stuff
	end
end

please avoid doing either of the things you just came up with
Modulo is a very useful mathematical operator. Division is fairly expensive, and that integer test is most likely extremely inefficient compared to checking whether a%1==0 (not to mention that that check isn't necessary when division itself isn't).

I didn't understand some of that, and I don't need to yet, but I did just start LunaLua like yesterday so I haven't explored it much so far.

lunatime is an API that keeps track of how many ticks and seconds have passed since the level has started, as well as providing functions for converting between the two.
% is the modulo operator in Lua.

[Novarender]

lunatime is an API that keeps track of how many ticks and seconds have passed since the level has started, as well as providing functions for converting between the two.
% is the modulo operator in Lua.

Oh. Thanks!

Do you know how many ticks are in a second in Lua?
EDIT: Nvm

[Emral]

lunatime is an API that keeps track of how many ticks and seconds have passed since the level has started, as well as providing functions for converting between the two.
% is the modulo operator in Lua.

Oh. Thanks!

Do you know how many ticks are in a second in Lua?

Approximately 64. 2500/39, to be exact.

[Novarender]

I was trying to use things like Player.speedX and Player.powerup as values, but it didn't work. The site says it is a "field" type of command. What's a field and how do I use it?

[Quantumenace]

Is it possible to force Mario to enter ANY state, such as his statue form? I might deprive the tanooki suit of its flight power and redesign it as a metal cap from Super Mario 64. If I can't do this, I might also just make a separate powerup entirely that changes Mario's properties.

Try looking at the player memory offsets 0x4A, 0x4C and 0x4E, which have to do with the statue form. I haven't experimented much with this. I'd think Mario can't move with it enabled though.

Also, how can I use "loop while"? I tried it but I couldn't figure out how to format it properly.

"while" is itself a loop command.

One more thing: Is Player.speedX outdated? I tried to use it and it said it didn't exist.

"Player" (capitalized) is the name of the table of player-related functions. The name for player 1 is "player". "player.speedX" will work.

[Novarender]

Is it possible to force Mario to enter ANY state, such as his statue form? I might deprive the tanooki suit of its flight power and redesign it as a metal cap from Super Mario 64. If I can't do this, I might also just make a separate powerup entirely that changes Mario's properties.

Try looking at the player memory offsets 0x4A, 0x4C and 0x4E, which have to do with the statue form. I haven't experimented much with this. I'd think Mario can't move with it enabled though.

Ok. It doesn't matter if he can move. I have plans.

One more thing: Is Player.speedX outdated? I tried to use it and it said it didn't exist.

"Player" (capitalized) is the name of the table of player-related functions. The name for player 1 is "player". "player.speedX" will work.

Yes, I just realised this before I saw your comment. I don't know why the site kept capitalizing Player.

[PixelPest]

It capitalizes "Player" to indicate that that property belongs to all objects of the Player class, such as the "player" object. Anything that isn't a constructor or a static function in a class is inherited by the class objects on instantiation (creation). This includes methods like "kill" and fields like "speedX". The constructors and static functions are called by the class itself and not as part of a specific object so when using a function like "get" within the Player class, you will call it with a capital "P" ("Player.get")

[Hoeloe]

lunatime is an API that keeps track of how many ticks and seconds have passed since the level has started, as well as providing functions for converting between the two.
% is the modulo operator in Lua.

Oh. Thanks!

Do you know how many ticks are in a second in Lua?

Approximately 64. 2500/39, to be exact.

First, lunatime, being a core API, doesn't need to be explicitly loaded. You can just use it.

Secondly, lunatime has a function called lunatime.toSeconds (as well as lunatime.toTicks) used for converting values between seconds and ticks so that you don't have to use obtuse calculations like 2500/39 and can use the more readable lunatime.toTicks(1).

I also wouldn't worry about a single modulo use. The0x539 is right that modulus is a fairly expensive operator compared to something like addition, but it's not going to lag up your game any time soon.

[Taycamgame]

What is the meaning of 2500/39, and why isn't that something else like 2000/40?

[The0x539]

What is the meaning of 2500/39, and why isn't that something else like 2000/40?

A tick lasts 15.6 milliseconds (this probably wasn't intended but it's the way things are). With this length, "39 ticks pass in 2500 milliseconds" is the smallest integer expression of the ratio between ticks and milliseconds.

[Novarender]

How do I use and format "while"? Can you give an example?
What about math.flor and math.ceil?
Also, what is the default jump height?

[The0x539]

How do I use and format "while"? Can you give an example?
What about math.flor and math.ceil?
Also, what is the default jump height?

Code: Select all

while someCondition do
	--do stuff
end

repeat
	--do stuff
until someCondition

floor and ceil round up and down to the nearest integer.
The default jump "height" is 20 ticks.

[Quantumenace]

while (condition) do
...
end

example:

Code: Select all

i=1
while i<=10 do
i=i+1
end

x = math.floor(num)
-rounds down to nearest integer
x = math.ceil(num)
-rounds up to nearest integer

The jump height isn't a fixed number, it depends on the character, gravity, a certain jump momentum timer IIRC and how fast the character is running.

[Novarender]

Can you tell me what's wrong here?

This is script for a triple jump sequence (TJS):

Code: Select all

--double jump
function onJumpEnd() --after landing on ground from jump

	while loop < 64 do --for 1 second
		
		if player.speedX > 4 or player.speedX < -4 then --if fast enough
		Defines.jumpheight = 100 --can jump higher (double jump) [set to high number for testing]
		else --if too slow
		Defines.jumpheight = 20 --jump normally
		end		
		loop = loop + 1 --adding to timer
	
	end
	loop = 0 --reset timer
	Defines.jumpheight = 20 --jump normally after 1 second
	
end

For some reason, it worked once but in a glitchy way, and since then I probably modified it, but I still don't know why it's not working. Nothing is failing except the fact that he doesn't do a double jump (in a TJS).

[Quantumenace]

It's important to note that a loop doesn't wait for the next tick. That won't take place over a second, it will just run that code 64 times in a row right when you land.

What you'll want to do is have a timer variable that is set to 64 when you land. Then, on onTick() you'll want to check if it isn't zero, decrease the timer by 1, and do the code for the jump. You don't need a loop for that.

[Novarender]

What you'll want to do is have a timer variable that is set to 64 when you land. Then, on onTick() you'll want to check if it isn't zero, decrease the timer by 1, and do the code for the jump. You don't need a loop for that.

How exactly could I do this? It needs to be within "onJumpEnd", and it never works when I try to use "function onTick()" in something else. It just freezes.
Is there a different way I can use onTick()?