[Map save/reload stream lua function problem]

Is there currently a way to do it in memory only?

[Map save/reload stream lua function problem]

Hi,

I'm trying to get lua examples for Map's Save and Reload functions working. If you try the example from https://www.ultraengine.com/learn/Map_Save?lang=lua , sol complains about args (with a StreamBuffer at least). It's not clear to me what to feed it for in-memory stuff.

I assume it's outdated because it's trying to call this

scene:Save(stream, "game.sav")

 

But save and reload do not take a string whatsoever as a second arg in lua docs. I assume changing the examples to do something like this is the way?

 

local buffer = CreateBuffer(1024)
local stream = CreateBufferStream(buffer)

-- Create a scene
local scene = CreateMap()

-- .... 

-- Save the starting scene to an in memory buffer
scene:Save(stream)

This appears to work, but it's unclear to me how to do the next two things:

1. seek to beginning of stream: I tried this `stream = CreateStreamBuffer(stream)`. an API to seek to beginning of oft-reused buffers for cute tricks would be nice though

2. Actually reload a map from memory? `Map:Reload(Stream)` complains about args as well when trying a stream arg, it appears only the unary string function exists.

I understand I can work around it with disk like so, maybe the old API was shorthand for this. But I'd like to avoid all disk I/O for reasons

scene:Save('foo.sav')

-- Main loop
while not window:Closed() and not window:KeyDown(KEY_ESCAPE) do
    -- Reload the starting scene when space key is pressed
    if window:KeyHit(KEY_SPACE) then
        scene:Reload('foo.sav')
    end
    world:Update()
    world:Render(framebuffer)
end

 

If something like "`scene:Reload(stream, LOAD_DEFAULT)`" worked again that would be the money. Appreciate any input

[Multiplayer with Lua]

1 hour ago, Josh said:

Lua DLL modules need to be placed in the /Modules folder. Lua code file modules should be placed in /Source.

Enet is nice to use but it doesn't support NAT punch-through, so it might not be very useful for modern networked games.

The P2P system is pretty nice because when the lobby owner leaves, ownership gets transferred to another player. This acts like a dedicated server without needing to program and maintain one.

ahh great, I had dlls next to exe, thanks. Fair point on ENet, just throwing out there are alternatives

[Multiplayer with Lua]

Beware steamworks lobby is P2P only. This made me curious about something else tho, it appears lua's require doesnt work? I was trying it with enet, eg `require "enet"` and it blows up. If require isnt working, that would be nice to become available so the reams of existing solutions (eg, love community) could be used

 

I did look at the Plugin architecture but that looks unrelated

[Initial speed of an object]

I had to do something kind of similar with a bowling ball. What I did was checked velocity, and if it was below a threshold I flat out set velocity to the minimum for that axis in UpdatePhysics()

 

I'd recommend to update your velocity in UpdatePhysics() if possible, if I recall correctly it always runs at a constant rate regardless of FPS, where UpdateWorld does NOT. if you have to set velocity in update world, scale it by Time:GetSpeed() so its not jittery

[Tying entities to C++ code]

I'm working on something using lua right now and it' starting to get big to the point I want to better manage the code. I've considered two things: trying to use flowgraph for all gameplay code or just switching to C++ which I would prefer.

 

I searched a bit and only found the suggestion of using hooks. I'd like placing something in the editor, and then pointing a C++ class at it for behavior but that doesn't seem to exist.

 

Only idea I have so far: use a pivot and a key value pair with something like ("ClassName", "MyClass") and searching entities on load and gluing things up there, but that would probably take RTTI . What I'm basically after is avoiding creating objects procedurally.

 

Am I missing something obvious? Anyone else handle this? If not, has anyone had massive flowgraphs handling gamplay instead of massive player luas?