check-es3-support.cc

// check if OpenGL ES 3.0 is supported

#include <cstdio>
#include <EGL/egl.h>

#ifndef EGL_OPENGL_ES3_BIT
#define EGL_OPENGL_ES3_BIT 0x40
#endif

int
main(int argc, char *argv[])
{
        EGLDisplay display = eglGetDisplay(EGL_DEFAULT_DISPLAY);
        eglInitialize(display, 0, 0); 

        const EGLint attribs[] { EGL_NONE };

        EGLConfig config;
        EGLint num_configs;
        eglChooseConfig(display, attribs, &config, 1, &num_configs);

        if (!num_configs) {
                fprintf(stderr, "no configs found?\n");
                return 1;
        }

        EGLint conformant;
        eglGetConfigAttrib(display, config, EGL_CONFORMANT, &conformant);

        struct {
                EGLint bit;
                const char *name;
        } conformant_bits[]
                {
#define D(bit) { bit, #bit }
                  D(EGL_OPENGL_BIT),
                  D(EGL_OPENGL_ES_BIT),
                  D(EGL_OPENGL_ES2_BIT),
                  D(EGL_OPENGL_ES3_BIT),
                  D(EGL_OPENVG_BIT)
#undef D
                };

        printf("conformant:");

        for (auto& b : conformant_bits) {
                if (conformant & b.bit)
                        printf(" %s", b.name);
        }

        putchar('\n');

        return 0;
}