Some questions about native extensions

Questions
#1

I got some problems when trying to write native extensions.
All libraries release for x64.
Version: 1.2.164

  1. We can get the buffer value using getbytes(). How can I write data to the buffer?
  2. I was building static libraries in MVSC 2019. Always got that message. I don’t know if I did anything wrong in Visual. But if build a dynamic library, everything works.
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  3. If put dlls in res, then crash.
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    Image 5.png865×365 18.2 KB

    (Sorry, that is not in English, but the meaning I think is clear. Crash.)
    But it’s okay if the dll is in the root.
    May need to bundle, but I tried with the dll in the res. Then error with a missing function from the library.

Libraries.
Dynamic in the project. Dll in the root and everything works.
Static: libvorbis.zip (605.9 KB)

Project: Simple_project.zip (9.2 MB)

No crashes and errors if the dynamic link library and dll in root

#2

OBJ files are not supported, so Defold complains about them. Just don’t put them under the extension dir.

Did you write the actual extension? Bridge between Lua and ogg/vorbis libs.

#3

Yeah. Without libraries extension works. And works if dinamic library. I did not have obj files, only lib. Sorry if I didn’t fully understand what you mean by obj. I mean .obj, but I built only .lib

#4

  1. You pass in a void** which means it returns the pointer where the bytes are stored. Cast the pointer appropriately, and store your bytes directly.

  2. As @sergey.lerg mentioned, we only support .lib files. We recommend statically linked libraries. If you use dynamically linked libraries, we don’t support that in a very good manner yet, as you noticed, since we set a path to the .dll’s when doing Build and run. During the bundling step though, you can copy files if you use the project.bundle_resources property (see project settings)

#5

Sorry, I do not understand 1.
Lua:
local res = resource.load("/assets/sound.ogg")
decodeogg.decodeogg(res)
I loss my full .cpp file. But there was something:
dmBuffer::HBuffer buffer;
dmScript::LuaHBuffer *lua_buffer = dmScript::CheckBuffer(L, 1);
buffer = lua_buffer->m_Buffer;
int size;
uint8_t* bytes;
dmBuffer::GetBytes(buffer, (void**)&bytes, &size);
//If I write bytes to file, then I get same as I pass to res.load

I seem to have begun to understand, do I need to change the values ​​in bytes?

#6

I have bytes. It’s ogg file. When I convert, I get wav file. I can’t write it in buffer, because other size. Right?

#7

That is a correct way to load an asset from the bundled assets, and getting hold of the data in C++.

If I write bytes to file, then I get same as I pass to res.load

Yes, that should be the full contents of the .ogg file.

Not sure what you mean?

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#8

I don’t know, how change buffer. I want some like:
local res = resource.load("/assets/sound.ogg")
.ogg file in res
decodeogg.decodeogg(res)
Now .wav in res

I don’t know, how write wav in buffer, where ogg.
Does the buffer have a fixed size? If so, how to change it or recreate buffer.

#9

Since the conversion will most likely need a different number of bytes, you need to create a new buffer to store your wav buffer to. Using dmBuffer::GetBytes() you’ll get both the pointer to the source bytes and a pointer to where to store the destination bytes.

As for the actual wav conversion, you’ll need to see the api of the framework you are using for the conversion.

A question though: Why convert to .wav? We support playing both .ogg and .wav, but there’s a benefit of smaller disc size when using .ogg and also faster playback on devices.

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#10

https://forum.defold.com/t/sound-lags-in-calculations/63978/7
In one of my functions, calculations occur and because of this freeze the sound. I started using OpenAL, but it only supports wav, which is large in size. I want to store files in ogg, and before transferring to OpenAL, convert them to wav.

I’ll try use dmBuffer :: Create (). Thanks.

#11

Everything worked out. Implemented so:

const dmBuffer::StreamDeclaration streams_decl[] = 
{
	{dmHashString64("byte"), dmBuffer::VALUE_TYPE_UINT8, 1},
};

dmBuffer::Result r_create = dmBuffer::Create(out_size, streams_decl, 1, &buffer);
if (r_create == dmBuffer::RESULT_OK) 
{
	char* wav_bytes;
	uint32_t wav_size;
	dmBuffer::Result r_get_wav_bytes = dmBuffer::GetBytes(buffer, (void**)&wav_bytes, &wav_size);
	if (r_get_wav_bytes == dmBuffer::RESULT_OK) 
	{
		for(size_t i = 0;i < wav_size;++i)
		{
			wav_bytes[i] = out_bytes[i];
		}
		lua_buffer->m_Buffer = buffer;

I will add to the github. It may not be useful to anyone as an extension, but I think it will help someone as an example.

Thank you for your help!

About the libraries. I think the problem is in the visual studio. I still can’t understand why static libraries write about some kind of info.obj, and dynamic libraries work perfectly. The source is one. I’ll try reinstalling it, hope it helps

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#12

Solved:
Project Property->C/C++->Code generation->runtime library->MT
Project Property->Additional->Whole Program Optimization ->No

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