xenocara/xserver/glamor/glamor_egl.h
2019-12-12 06:05:17 +00:00

78 lines
3.1 KiB
C

/*
* Copyright © 2016 Red Hat, Inc.
*
* Permission is hereby granted, free of charge, to any person obtaining a
* copy of this software and associated documentation files (the "Software"),
* to deal in the Software without restriction, including without limitation
* the rights to use, copy, modify, merge, publish, distribute, sublicense,
* and/or sell copies of the Software, and to permit persons to whom the
* Software is furnished to do so, subject to the following conditions:
*
* The above copyright notice and this permission notice (including the next
* paragraph) shall be included in all copies or substantial portions of the
* Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
* THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
* FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
* DEALINGS IN THE SOFTWARE.
*
* Authors:
* Adam Jackson <ajax@redhat.com>
*/
#ifndef GLAMOR_EGL_H
#define GLAMOR_EGL_H
#define MESA_EGL_NO_X11_HEADERS
#define EGL_NO_X11
#include <epoxy/gl.h>
#include <epoxy/egl.h>
#include <glamor_egl_ext.h>
/*
* Create an EGLDisplay from a native display type. This is a little quirky
* for a few reasons.
*
* 1: GetPlatformDisplayEXT and GetPlatformDisplay are the API you want to
* use, but have different function signatures in the third argument; this
* happens not to matter for us, at the moment, but it means epoxy won't alias
* them together.
*
* 2: epoxy 1.3 and earlier don't understand EGL client extensions, which
* means you can't call "eglGetPlatformDisplayEXT" directly, as the resolver
* will crash.
*
* 3: You can't tell whether you have EGL 1.5 at this point, because
* eglQueryString(EGL_VERSION) is a property of the display, which we don't
* have yet. So you have to query for extensions no matter what. Fortunately
* epoxy_has_egl_extension _does_ let you query for client extensions, so
* we don't have to write our own extension string parsing.
*
* 4. There is no EGL_KHR_platform_base to complement the EXT one, thus one
* needs to know EGL 1.5 is supported in order to use the eglGetPlatformDisplay
* function pointer.
* We can workaround this (circular dependency) by probing for the EGL 1.5
* platform extensions (EGL_KHR_platform_gbm and friends) yet it doesn't seem
* like mesa will be able to adverise these (even though it can do EGL 1.5).
*/
static inline EGLDisplay
glamor_egl_get_display(EGLint type, void *native)
{
/* In practise any EGL 1.5 implementation would support the EXT extension */
if (epoxy_has_egl_extension(NULL, "EGL_EXT_platform_base")) {
PFNEGLGETPLATFORMDISPLAYEXTPROC getPlatformDisplayEXT =
(void *) eglGetProcAddress("eglGetPlatformDisplayEXT");
if (getPlatformDisplayEXT)
return getPlatformDisplayEXT(type, native, NULL);
}
/* Welp, everything is awful. */
return eglGetDisplay(native);
}
#endif