1/*
2 * Copyright © 2016 Red Hat, Inc.
3 *
4 * Permission is hereby granted, free of charge, to any person obtaining a
5 * copy of this software and associated documentation files (the "Software"),
6 * to deal in the Software without restriction, including without limitation
7 * the rights to use, copy, modify, merge, publish, distribute, sublicense,
8 * and/or sell copies of the Software, and to permit persons to whom the
9 * Software is furnished to do so, subject to the following conditions:
10 *
11 * The above copyright notice and this permission notice (including the next
12 * paragraph) shall be included in all copies or substantial portions of the
13 * Software.
14 *
15 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
16 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
17 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
18 * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
19 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
20 * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
21 * DEALINGS IN THE SOFTWARE.
22 *
23 * Authors:
24 *	Adam Jackson <ajax@redhat.com>
25 */
26
27#ifndef GLAMOR_EGL_H
28#define GLAMOR_EGL_H
29
30#define MESA_EGL_NO_X11_HEADERS
31#define EGL_NO_X11
32#include <epoxy/gl.h>
33#include <epoxy/egl.h>
34#include <glamor_egl_ext.h>
35
36/*
37 * Create an EGLDisplay from a native display type. This is a little quirky
38 * for a few reasons.
39 *
40 * 1: GetPlatformDisplayEXT and GetPlatformDisplay are the API you want to
41 * use, but have different function signatures in the third argument; this
42 * happens not to matter for us, at the moment, but it means epoxy won't alias
43 * them together.
44 *
45 * 2: epoxy 1.3 and earlier don't understand EGL client extensions, which
46 * means you can't call "eglGetPlatformDisplayEXT" directly, as the resolver
47 * will crash.
48 *
49 * 3: You can't tell whether you have EGL 1.5 at this point, because
50 * eglQueryString(EGL_VERSION) is a property of the display, which we don't
51 * have yet. So you have to query for extensions no matter what. Fortunately
52 * epoxy_has_egl_extension _does_ let you query for client extensions, so
53 * we don't have to write our own extension string parsing.
54 *
55 * 4. There is no EGL_KHR_platform_base to complement the EXT one, thus one
56 * needs to know EGL 1.5 is supported in order to use the eglGetPlatformDisplay
57 * function pointer.
58 * We can workaround this (circular dependency) by probing for the EGL 1.5
59 * platform extensions (EGL_KHR_platform_gbm and friends) yet it doesn't seem
60 * like mesa will be able to adverise these (even though it can do EGL 1.5).
61 */
62static inline EGLDisplay
63glamor_egl_get_display(EGLint type, void *native)
64{
65    /* In practise any EGL 1.5 implementation would support the EXT extension */
66    if (epoxy_has_egl_extension(NULL, "EGL_EXT_platform_base")) {
67        PFNEGLGETPLATFORMDISPLAYEXTPROC getPlatformDisplayEXT =
68            (void *) eglGetProcAddress("eglGetPlatformDisplayEXT");
69        if (getPlatformDisplayEXT)
70            return getPlatformDisplayEXT(type, native, NULL);
71    }
72
73    /* Welp, everything is awful. */
74    return eglGetDisplay(native);
75}
76
77#endif
78