Creating a C library

[BenStigsen]

So I've been messing around with SDL2, tigr and kit.

What I've done so far is just take those libraries and compile them like:

gcc -lgdi32 -lwinmm -luser32 -c -o tigr.o tigr.c
gcc -lgdi32 -lwinmm -luser32 -shared -o tigr.dll tigr.o

And while this does create a .dll file, I am wondering if there's a better way to it.

My test library currently looks like so:

var lib = clib.load('./kit.dll')

var kit_create = lib.define('kit_create', clib.ptr, clib.char_ptr, clib.int, clib.int, clib.int)
def create(title, w, h) {
  return kit_create(title, w, h, 0)
}

var kit_step = lib.define('kit_step', clib.bool, clib.ptr, clib.ptr)
def step(ctx) {
  return kit_step(ctx, clib.double)
}

var kit_destroy = lib.define('kit_destroy', clib.void, clib.ptr)
def destroy(ctx) {
  kit_destroy(ctx)
}

There's currently some issues with using structs, and it also seems to run inconsistently. What I was thinking is, would it be better if I made a wrapper library in C, using blade.h? Should I just create a .dll from this or would I have to build it into the Blade executable?

[mcfriend99]

Have you checked out the blade-ext-demo repository?? That's an example repository showing how to achieve this easily. Though the project uses cmake, it's not exactly a requirement. The basic requirements are:

• Dynamically link against the libblade
• Added the <blade_install_path>/includes to your includes path

You can learn more about the API by looking at the builtin-packages under the packages directory or src/standard directory of Blade source code. It's very similar to the builtin methods API as well.

[BenStigsen]

Yeah but does this build an entirely new Blade executable or DLL with those libraries?
Because ideally I wouldn't need to modify basic Blade installation, for someone to use SDL2 or something.

[mcfriend99]

No. It generates a Blade extension dll. If you create a directory .blade/bin at the root of the application and run it, it will load it as an extension that can then be used in the project.

For example, if you build the demo project, it will create a demo.dll (or demo.so for Linux OS and demo.dylib on MacOS) file for you. If you put it in a directory called .blade/bin, you will be able to import it like this in your application.

import demo

demo.say_hello()

You should be greeted by Hello, world!.

Also, note that the sqlite based message in the CMakeLists.txt file is irrelevant and is no longer valid.

[BenStigsen]

Ah okay. Well, in that case. I don't know how to compile the blade-ext-demo if I follow the instructions:

cmake -B ./build -DCMAKE_BUILD_TYPE=Release -DBLADE_ROOT="D:/Projects/Blade/blade/build/blade"
cmake --build build --config Release

I've tried changing the path to forward slashes and to just D:\Projects\Blade\blade instead of the build, but I keep getting errors.

So I get:

CMake Error at CMakeLists.txt:3 (project):
   'nmake' '-?'

  failed with:
   The system cannot find the file specified

I also got errors with C compilers, but I defined them in the CMake file:

set(CMAKE_CXX_COMPILER "C:/mingw64/bin/g++")
set(CMAKE_C_COMPILER "C:/mingw64/bin/gcc")

So now I'm just getting the The system cannot find the file specified error.

---

If you put it in a directory called .blade/bin, you will be able to import it like this in your application.

Nice, I didn't know about this!

[mcfriend99]

For the last comment, See https://bladelang.com/tutorial/modules.html#first-class-package-management

[mcfriend99]

Do you have the mingw32-make in your path?? If you don't, you can get it by installing TCC or WinLibs compiler and adding it to your path (Or simply add the directory C:/mingw64/bin/ to your path based on what I see). Without changing anything in the CMakeLists.txt file and provided that the blade.exe resides in the directory D:/Projects/Blade/blade/build/blade, you can change the first command to:

cmake -B ./build -DCMAKE_BUILD_TYPE=Release -DBLADE_ROOT="D:/Projects/Blade/blade/build/blade" -DCMAKE_MAKE_PROGRAM=mingw32-make -G "Unix Makefiles"

[BenStigsen]

Alright, your make suggestion made it work! Here's a GIF of a window opening with a loop!

But, I'm having my hard time wrapping my brain around, how to make it a Blade module. Do I just keep the DLL files in the .blade/bin, then what do I do with my index.b, draw.b and so on? Do I move these into .blade/libs and import _kit. What would be the best way to make something easily installable or perhaps Nyssa compatible with a C module?

It might be a vague question. But even though I've looked at the sqlite and json modules, I don't quite see how I could use the same system as those, since they don't make use of a .blade/ folder.

[mcfriend99]

Your suggestion works perfectly. You can convert it into a nyssa package and use the nyssa post_installation script option to copy the required dlls into the proper directory.

• More information about the post_install
• Sample package using the post_install

[mcfriend99]

Quick suggestion, you could use index.b instead of main.b to make it easy to import the package. It's also easier to run with the command blade . that way.

Also, which editor is this and how were you able to make it recognise Blade syntax?? I'm really interested.

[BenStigsen]

I'm using lite-xl for writing code in Blade. I added the Blade syntax highlighting to the plugins repo as language_blade.

[BenStigsen]

Sort of related last thing.
Is there any thing gamedev wise you wish was a library for Blade? Because while Kit is good, it's only for Windows. So perhaps you'd prefer Tigr, SDL2 or something else?

[mcfriend99]

Is the project on GitHub??

[BenStigsen]

Not yet. I'll post here when I make it public (within a week).
I also still have to add the HTTP router module to Nyssa.

[BenStigsen]

I sort of changed my mind. I'm now considering kit or raylib. Still not certain which one I'll choose. But here's little example with raylib 😄

[mcfriend99]

I believe raylib is more matured and cross platform. I think it's a better choice and better suited to Blade as a package.

[BenStigsen]

Yep, the API is very simple and will fit in nicely with Blade.

Raylib it is!

[mcfriend99]

So I've been messing around with SDL2, tigr and kit.

What I've done so far is just take those libraries and compile them like:

gcc -lgdi32 -lwinmm -luser32 -c -o tigr.o tigr.c
gcc -lgdi32 -lwinmm -luser32 -shared -o tigr.dll tigr.o

And while this does create a .dll file, I am wondering if there's a better way to it.

My test library currently looks like so:

var lib = clib.load('./kit.dll')

var kit_create = lib.define('kit_create', clib.ptr, clib.char_ptr, clib.int, clib.int, clib.int)
def create(title, w, h) {
  return kit_create(title, w, h, 0)
}

var kit_step = lib.define('kit_step', clib.bool, clib.ptr, clib.ptr)
def step(ctx) {
  return kit_step(ctx, clib.double)
}

var kit_destroy = lib.define('kit_destroy', clib.void, clib.ptr)
def destroy(ctx) {
  kit_destroy(ctx)
}

There's currently some issues with using structs, and it also seems to run inconsistently. What I was thinking is, would it be better if I made a wrapper library in C, using blade.h? Should I just create a .dll from this or would I have to build it into the Blade executable?

This came to my attention again specifically the statement "There's currently some issues with using structs". If you knew the elements in the structure and their data type, you can use struct packing available in the struct module to create the struct pointer and pass it in as clib.ptr. Blade struct packing behaves the same as and uses the same syntax as PHP's struct packing.

See the structs documentation.

[BenStigsen]

I've been busy with school and work so I haven't gotten around to the raylib library for Blade. But I can see that you have started Blade projects based on raylib and raygui for these 😄

Do you still want me to make a 1:1 raylib library?

[mcfriend99]

More of an experiment and a way to test the clib module ahead of v0.0.84 and not something I'm planning to release. Will be taking down the GitHub repo as soon as th clib module matures.