External library woes

Thanks Jaymie! Having an easily transferrable solution would be the ideal solution, as in having it as a nodeset to just pop over to different computers. There might be a middle ground if its only a matter of the library being installed to the same location that requires rebuilding. I'm using Homebrew to install the libraries, so both cfitsio and eventual other libraries installed using that should always reside at /usr/local/Cellar if not changed by the end user.

Cfitsio is at least mulit-platform and supported on Apple Silicon, so hopefully it isn't the worst of libraries to try to include

Aha! Could the /usr/***/Cellar be dependant on architecture in the cmake file perhaps?

I also have to admit to using some performance enhancers for this experiment (chatGPT), but as it compiles fine, and it is the linker that is complaining, I think it has been coaxed into providing something that should run at least.

Using the example you provided, I got a little bit farther. I did not get an error when running your example node, but this one still spits out a linker error:

ld: warning: passed two min versions (10.10.0, 10.12) for platform macOS. Using 10.12. Undefined symbols for architecture x86_64: "_fits_getimg_param", referenced from: _display_fits_image in composite-Aq6gm3-95525c.o ld: symbol(s) not found for architecture x86_64 clang: error: linker command failed with exit code 1 (use -v to see invocation)

C code for the node:

/**
 * @file
 * MM.image.fetchFits node implementation.
 *
 * @copyright Copyright © 2012–2022 Magneson.
 * This code may be modified and distributed under the terms of the MIT License.
 * For more information, see https://vuo.org/license.
 */
 
#include "node.h"
#include "fitsio.h"
#include "fitsio2.h"
#include <OpenGL/gl.h>
 
 
VuoModuleMetadata({
                     "title" : "Fetch FITS",
                     "description" : "Fetches a FITS file as a Vuo Image",
                     "keywords" : [ ],
                     "version" : "1.0.0",
                     "dependencies" : [ "cfitsio.dylib" ],
                 });
 
VuoImage display_fits_image(const char *filename) {
    fitsfile *fptr;
    int status = 0;
    int bitpix, naxis;
    long naxes[FITS_MAX_DIM];
    unsigned char *pixels;
    int x, y;
 
    // Open FITS file.
    fits_open_file(&fptr, filename, READONLY, &status);
 
    // Get the image dimensions and type.
    fits_get_img_param(fptr, FITS_MAX_DIM, &bitpix, &naxis, naxes, &status);
 
    // Allocate memory for the pixel data.
    pixels = (unsigned char *) malloc(naxes[0] * naxes[1] * sizeof(unsigned char));
 
    // Read the image data.
    long fpixel[FITS_MAX_DIM];
    fpixel[0] = 1;
    fpixel[1] = 1;
    long nelements = naxes[0] * naxes[1];
    for (int i = 2; i <= naxis; i++) {
        nelements *= naxes[i-1];
        fpixel[i] = 1;
    }
    fits_read_pix(fptr, TBYTE, fpixel, nelements, NULL, pixels, NULL, &status);
 
    // Close the FITS file.
    fits_close_file(fptr, &status);
 
    // Create a GL texture from the pixel data.
    unsigned int textureName;
    glGenTextures(1, &textureName);
    glBindTexture(GL_TEXTURE_2D, textureName);
    glTexImage2D(GL_TEXTURE_2D, 0, GL_LUMINANCE, naxes[0], naxes[1], 0, GL_LUMINANCE, GL_UNSIGNED_BYTE, pixels);
    glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_CLAMP_TO_EDGE);
    glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_CLAMP_TO_EDGE);
    glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR);
    glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR);
 
    // Create VuoImage from GL texture.
    VuoImage image = VuoImage_make(textureName, GL_LUMINANCE, naxes[0], naxes[1]);
 
    // Free the pixel data.
    free(pixels);
 
    // Return VuoImage.
    return image;
}
 
void nodeEvent
(
        VuoInputData(VuoText) url,
        VuoOutputData(VuoImage) fitsImage
)
{
    *fitsImage = display_fits_image(url);
}

Relevant part of CMakeLists.txt:

set(compiledNodes "")
foreach (source ${sources})
    set(compiledNode "")
    set(bitcodeParts "")
    list(LENGTH CMAKE_OSX_ARCHITECTURES archCount)
    foreach (arch ${CMAKE_OSX_ARCHITECTURES})
        get_filename_component(bitcode ${source} NAME_WLE)
        set(compiledNode "${bitcode}.vuonode")
        if (archCount EQUAL 1)
            set(bitcode "${bitcode}.vuonode")
        else()
            set(bitcode "${bitcode}-${arch}.vuonode")
        endif()
 
        add_custom_command(
            DEPENDS "${PROJECT_SOURCE_DIR}/${source}"
            COMMENT "Compiling node class (${arch})"
            COMMAND ${VUO_FRAMEWORK}/../vuo-compile
                "${PROJECT_SOURCE_DIR}/${source}"
                --target ${arch}-apple-macosx10.12.0
                --output ${bitcode}
                --header-search-path /usr/local/Cellar/cfitsio/4.2.0/include  # for #include "fitsio.h"
                OUTPUT ${bitcode}
        )
 
        if (archCount GREATER 1)
            list(APPEND bitcodeParts ${bitcode})
        endif()
    endforeach()
 
    if (archCount GREATER 1)
        add_custom_command(
            DEPENDS ${bitcodeParts}
            COMMENT "Merging into multi-architecture file"
            COMMAND lipo -create ${bitcodeParts} -output ${compiledNode}
            OUTPUT ${compiledNode}
        )
    endif()
 
    list(APPEND compiledNodes ${compiledNode})
endforeach()
 
#Name your nodeset
set(nodeset MM.image.vuonode)
add_custom_command(
    DEPENDS ${compiledNodes}
    COMMENT "Packaging node set and copying to User Modules folder"
    COMMAND zip --quiet --junk-paths ${nodeset}
        ${compiledNodes}
    COMMAND cp ${nodeset} ${userModules}
    OUTPUT ${nodeset}
)
 
set(installedDylib ${userModules}/libcfitsio.dylib)
add_custom_command(
    COMMENT "Copying libcfitsio.dylib to User Modules folder"
    COMMAND cp /usr/local/Cellar/cfitsio/4.2.0/lib/libcfitsio.dylib ${installedDylib}  
    OUTPUT ${installedDylib}
)
 
 
add_custom_target(node ALL
    DEPENDS ${installedNode} ${installedDylib}
)