github.com/SahandAslani/gomobile@v0.0.0-20210909130135-2cb2d44c09b2/exp/gl/glutil/context_x11.go (about)

     1  // Copyright 2014 The Go Authors. All rights reserved.
     2  // Use of this source code is governed by a BSD-style
     3  // license that can be found in the LICENSE file.
     4  
     5  //go:build linux && !android
     6  // +build linux,!android
     7  
     8  package glutil
     9  
    10  /*
    11  #cgo LDFLAGS: -lEGL
    12  #include <EGL/egl.h>
    13  #include <stdio.h>
    14  #include <stdlib.h>
    15  
    16  void createContext(EGLDisplay *out_dpy, EGLContext *out_ctx, EGLSurface *out_surf) {
    17  	EGLDisplay e_dpy = eglGetDisplay(EGL_DEFAULT_DISPLAY);
    18  	if (!e_dpy) {
    19  		fprintf(stderr, "eglGetDisplay failed\n");
    20  		exit(1);
    21  	}
    22  	EGLint e_major, e_minor;
    23  	if (!eglInitialize(e_dpy, &e_major, &e_minor)) {
    24  		fprintf(stderr, "eglInitialize failed\n");
    25  		exit(1);
    26  	}
    27  	eglBindAPI(EGL_OPENGL_ES_API);
    28  	static const EGLint config_attribs[] = {
    29  		EGL_RENDERABLE_TYPE, EGL_OPENGL_ES2_BIT,
    30  		EGL_SURFACE_TYPE, EGL_PBUFFER_BIT,
    31  		EGL_BLUE_SIZE, 8,
    32  		EGL_GREEN_SIZE, 8,
    33  		EGL_RED_SIZE, 8,
    34  		EGL_CONFIG_CAVEAT, EGL_NONE,
    35  		EGL_NONE
    36  	};
    37  	EGLConfig config;
    38  	EGLint num_configs;
    39  	if (!eglChooseConfig(e_dpy, config_attribs, &config, 1, &num_configs)) {
    40  		fprintf(stderr, "eglChooseConfig failed\n");
    41  		exit(1);
    42  	}
    43  	static const EGLint ctx_attribs[] = {
    44  		EGL_CONTEXT_CLIENT_VERSION, 2,
    45  		EGL_NONE
    46  	};
    47  	EGLContext e_ctx = eglCreateContext(e_dpy, config, EGL_NO_CONTEXT, ctx_attribs);
    48  	if (e_ctx == EGL_NO_CONTEXT) {
    49  		fprintf(stderr, "eglCreateContext failed\n");
    50  		exit(1);
    51  	}
    52  	static const EGLint pbuf_attribs[] = {
    53  		EGL_NONE
    54  	};
    55  	EGLSurface e_surf = eglCreatePbufferSurface(e_dpy, config, pbuf_attribs);
    56  	if (e_surf == EGL_NO_SURFACE) {
    57  		fprintf(stderr, "eglCreatePbufferSurface failed\n");
    58  		exit(1);
    59  	}
    60  	if (!eglMakeCurrent(e_dpy, e_surf, e_surf, e_ctx)) {
    61  		fprintf(stderr, "eglMakeCurrent failed\n");
    62  		exit(1);
    63  	}
    64  	*out_surf = e_surf;
    65  	*out_ctx = e_ctx;
    66  	*out_dpy = e_dpy;
    67  }
    68  
    69  void destroyContext(EGLDisplay e_dpy, EGLContext e_ctx, EGLSurface e_surf) {
    70  	if (!eglMakeCurrent(e_dpy, EGL_NO_SURFACE, EGL_NO_SURFACE, EGL_NO_CONTEXT)) {
    71  		fprintf(stderr, "eglMakeCurrent failed\n");
    72  		exit(1);
    73  	}
    74  	if (!eglDestroySurface(e_dpy, e_surf)) {
    75  		fprintf(stderr, "eglDestroySurface failed\n");
    76  		exit(1);
    77  	}
    78  	if (!eglDestroyContext(e_dpy, e_ctx)) {
    79  		fprintf(stderr, "eglDestroyContext failed\n");
    80  		exit(1);
    81  	}
    82  }
    83  */
    84  import "C"
    85  
    86  import (
    87  	"runtime"
    88  )
    89  
    90  type contextGL struct {
    91  	dpy  C.EGLDisplay
    92  	ctx  C.EGLContext
    93  	surf C.EGLSurface
    94  }
    95  
    96  func createContext() (*contextGL, error) {
    97  	runtime.LockOSThread()
    98  	c := &contextGL{}
    99  	C.createContext(&c.dpy, &c.ctx, &c.surf)
   100  	return c, nil
   101  }
   102  
   103  func (c *contextGL) destroy() {
   104  	C.destroyContext(c.dpy, c.ctx, c.surf)
   105  	runtime.UnlockOSThread()
   106  }