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Diffstat (limited to 'glew/auto/EGL-Registry/extensions/KHR/EGL_KHR_platform_gbm.txt')
| -rw-r--r-- | glew/auto/EGL-Registry/extensions/KHR/EGL_KHR_platform_gbm.txt | 295 |
1 files changed, 295 insertions, 0 deletions
diff --git a/glew/auto/EGL-Registry/extensions/KHR/EGL_KHR_platform_gbm.txt b/glew/auto/EGL-Registry/extensions/KHR/EGL_KHR_platform_gbm.txt new file mode 100644 index 0000000..a4c04e0 --- /dev/null +++ b/glew/auto/EGL-Registry/extensions/KHR/EGL_KHR_platform_gbm.txt @@ -0,0 +1,295 @@ +Name + + KHR_platform_gbm + +Name Strings + + EGL_KHR_platform_gbm + +Contributors + + Chad Versace <chad.versace@intel.com> + Jon Leech (oddhack 'at' sonic.net) + Kristian Høgsberg <krh@bitplanet.org> + +Contacts + + Chad Versace <chad.versace@intel.com> + +Status + + Complete. + Approved by the EGL Working Group on January 31, 2014. + Ratified by the Khronos Board of Promoters on March 14, 2014. + +Version + + Version 3, 2016/01/04 + +Number + + EGL Extension #69 + +Extension Type + + EGL client extension + +Dependencies + + EGL 1.5 is required. + + This extension is written against the EGL 1.5 Specification (draft + 20140122). + +Overview + + This extension defines how to create EGL resources from native GBM + resources using the EGL 1.5 platform functionality (GBM is a Generic + Buffer Manager for Linux). + +New Types + + None + +New Procedures and Functions + + None + +New Tokens + + Accepted as the <platform> argument of eglGetPlatformDisplay: + + EGL_PLATFORM_GBM_KHR 0x31D7 + +Additions to the EGL Specification + + None. + +New Behavior + + To determine if the EGL implementation supports this extension, clients + should query the EGL_EXTENSIONS string of EGL_NO_DISPLAY. + + To obtain an EGLDisplay from an GBM device, call eglGetPlatformDisplay with + <platform> set to EGL_PLATFORM_GBM_KHR. The <native_display> parameter + specifies the GBM device to use and must either point to a `struct + gbm_device` or be EGL_DEFAULT_DISPLAY. If <native_display> is + EGL_DEFAULT_DISPLAY, then the resultant EGLDisplay will be backed by some + implementation-chosen GBM device. + + For each EGLConfig that belongs to the GBM platform, the + EGL_NATIVE_VISUAL_ID attribute is a GBM color format, such as + GBM_FORMAT_XRGB8888. + + To obtain a rendering surface from a GBM surface, call + eglCreatePlatformWindowSurface with a <dpy> that belongs to the GBM + platform and a <native_window> that points to a `struct gbm_surface`. If + <native_window> was created without the GBM_BO_USE_RENDERING flag, or if + the color format of <native_window> differs from the EGL_NATIVE_VISUAL_ID + of <config>, then the function fails and generates EGL_BAD_MATCH. + + It is not valid to call eglCreatePlatformPixmapSurface with a <dpy> that + belongs to the GBM platform. Any such call fails and generates + an EGL_BAD_PARAMETER error. + +Issues + + 1. Should this extension permit EGL_DEFAULT_DISPLAY as input to + eglGetPlatformDisplay? + + RESOLUTION: Yes. When given EGL_DEFAULT_DISPLAY, eglGetPlatformDisplay + returns an EGLDisplay backed by an implementation-chosen GBM device. + +Example Code + + // This example program creates an EGL surface from a GBM surface. + // + // If the macro EGL_KHR_platform_gbm is defined, then the program + // creates the surfaces using the methods defined in this specification. + // Otherwise, it uses the methods defined by the EGL 1.4 specification. + // + // Compile with `cc -std=c99 example.c -lgbm -lEGL`. + + #include <stdlib.h> + #include <string.h> + + #include <sys/types.h> + #include <sys/stat.h> + #include <fcntl.h> + + #include <EGL/egl.h> + #include <gbm.h> + + struct my_display { + struct gbm_device *gbm; + EGLDisplay egl; + }; + + struct my_config { + struct my_display dpy; + EGLConfig egl; + }; + + struct my_window { + struct my_config config; + struct gbm_surface *gbm; + EGLSurface egl; + }; + + static void + check_extensions(void) + { + #ifdef EGL_KHR_platform_gbm + const char *client_extensions = eglQueryString(EGL_NO_DISPLAY, EGL_EXTENSIONS); + + if (!client_extensions) { + // No client extensions string available + abort(); + } + if (!strstr(client_extensions, "EGL_KHR_platform_gbm")) { + abort(); + } + #endif + } + + static struct my_display + get_display(void) + { + struct my_display dpy; + + int fd = open("/dev/dri/card0", O_RDWR | FD_CLOEXEC); + if (fd < 0) { + abort(); + } + + dpy.gbm = gbm_create_device(fd); + if (!dpy.gbm) { + abort(); + } + + + #ifdef EGL_KHR_platform_gbm + dpy.egl = eglGetPlatformDisplay(EGL_PLATFORM_GBM_KHR, dpy.gbm, NULL); + #else + dpy.egl = eglGetDisplay(dpy.gbm); + #endif + + if (dpy.egl == EGL_NO_DISPLAY) { + abort(); + } + + EGLint major, minor; + if (!eglInitialize(dpy.egl, &major, &minor)) { + abort(); + } + + return dpy; + } + + static struct my_config + get_config(struct my_display dpy) + { + struct my_config config = { + .dpy = dpy, + }; + + EGLint egl_config_attribs[] = { + EGL_BUFFER_SIZE, 32, + EGL_DEPTH_SIZE, EGL_DONT_CARE, + EGL_STENCIL_SIZE, EGL_DONT_CARE, + EGL_RENDERABLE_TYPE, EGL_OPENGL_ES2_BIT, + EGL_SURFACE_TYPE, EGL_WINDOW_BIT, + EGL_NONE, + }; + + EGLint num_configs; + if (!eglGetConfigs(dpy.egl, NULL, 0, &num_configs)) { + abort(); + } + + EGLConfig *configs = malloc(num_configs * sizeof(EGLConfig)); + if (!eglChooseConfig(dpy.egl, egl_config_attribs, + configs, num_configs, &num_configs)) { + abort(); + } + if (num_configs == 0) { + abort(); + } + + // Find a config whose native visual ID is the desired GBM format. + for (int i = 0; i < num_configs; ++i) { + EGLint gbm_format; + + if (!eglGetConfigAttrib(dpy.egl, configs[i], + EGL_NATIVE_VISUAL_ID, &gbm_format)) { + abort(); + } + + if (gbm_format == GBM_FORMAT_XRGB8888) { + config.egl = configs[i]; + free(configs); + return config; + } + } + + // Failed to find a config with matching GBM format. + abort(); + } + + static struct my_window + get_window(struct my_config config) + { + struct my_window window = { + .config = config, + }; + + window.gbm = gbm_surface_create(config.dpy.gbm, + 256, 256, + GBM_FORMAT_XRGB8888, + GBM_BO_USE_RENDERING); + if (!window.gbm) { + abort(); + } + + #ifdef EGL_KHR_platform_gbm + window.egl = eglCreatePlatformWindowSurface(config.dpy.egl, + config.egl, + window.gbm, + NULL); + #else + window.egl = eglCreateWindowSurface(config.dpy.egl, + config.egl, + window.gbm, + NULL); + #endif + + if (window.egl == EGL_NO_SURFACE) { + abort(); + } + + return window; + } + + int + main(void) + { + check_extensions(); + + struct my_display dpy = get_display(); + struct my_config config = get_config(dpy); + struct my_window window = get_window(config); + + return 0; + } + +Revision History + + Version 3, 2016-01-04 (Jon Leech) + - Free config memory allocated in sample code (Public Bug 1445). + + Version 2, 2014/02/12 (Chad Versace) + - Change resolution of issue #1 from "no" to "yes". Now + eglGetPlatformDisplay accepts EGL_DEFAULT_DISPLAY for GBM. + + Version 1, 2014/01/22 (Jon Leech) + - Promote EGL_MESA_platform_gbm to KHR to go with EGL 1.5. |