EGL 是 OpenGL ES 渲染 API 和本地窗口系统(native platform window system)之间的一个中间接口层，它主要由系统制造商实现。文章来源：https://www.toymoban.com/news/detail-493145.html
使用 EGL 绘图的基本步骤
- Display(EGLDisplay) 是对实际显示设备的抽象。
- Surface（EGLSurface）是对用来存储图像的内存区域
- FrameBuffer 的抽象，包括 Color Buffer， Stencil Buffer ，Depth Buffer。Context (EGLContext) 存储 OpenGL ES绘图的一些状态信息。
使用EGL的绘图的一般步骤：文章来源地址https://www.toymoban.com/news/detail-493145.html
- 获取 EGL Display 对象：eglGetDisplay()
- 初始化与 EGLDisplay 之间的连接：eglInitialize()
- 获取 EGLConfig 对象：eglChooseConfig()
- 创建 EGLContext 实例：eglCreateContext()
- 创建 EGLSurface 实例：eglCreateWindowSurface()
- 连接 EGLContext 和 EGLSurface：eglMakeCurrent()
- 使用 OpenGL ES API 绘制图形：gl_*()
- 切换 front buffer 和 back buffer 送显：eglSwapBuffer()
- 断开并释放与 EGLSurface 关联的 EGLContext 对象：eglRelease()
- 删除 EGLSurface 对象
- 删除 EGLContext 对象
- 终止与 EGLDisplay 之间的连接
/*
* Copyright © 2011 Benjamin Franzke
*
* 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.
*/
#include "config.h"
#include <stdint.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <stdbool.h>
#include <math.h>
#include <assert.h>
#include <signal.h>
#include <linux/input.h>
#include <wayland-client.h>
#include <wayland-egl.h>
#include <wayland-cursor.h>
#include <GLES2/gl2.h>
#include <EGL/egl.h>
#include <EGL/eglext.h>
#include "xdg-shell-client-protocol.h"
#include <sys/types.h>
#include <unistd.h>
#include "shared/helpers.h"
#include "shared/platform.h"
#include "shared/weston-egl-ext.h"
struct window;
struct seat;
struct display {
struct wl_display *display;
struct wl_registry *registry;
struct wl_compositor *compositor;
struct xdg_wm_base *wm_base;
struct wl_seat *seat;
struct wl_pointer *pointer;
struct wl_touch *touch;
struct wl_keyboard *keyboard;
struct wl_shm *shm;
struct wl_cursor_theme *cursor_theme;
struct wl_cursor *default_cursor;
struct wl_surface *cursor_surface;
struct {
EGLDisplay dpy;
EGLContext ctx;
EGLConfig conf;
} egl;
struct window *window;
PFNEGLSWAPBUFFERSWITHDAMAGEEXTPROC swap_buffers_with_damage;
};
struct geometry {
int width, height;
};
struct window {
struct display *display;
struct geometry geometry, window_size;
struct {
GLuint rotation_uniform;
GLuint pos;
GLuint col;
} gl;
uint32_t benchmark_time, frames;
struct wl_egl_window *native;
struct wl_surface *surface;
struct xdg_surface *xdg_surface;
struct xdg_toplevel *xdg_toplevel;
EGLSurface egl_surface;
struct wl_callback *callback;
int fullscreen, maximized, opaque, buffer_size, frame_sync, delay;
bool wait_for_configure;
};
static const char *vert_shader_text =
"uniform mat4 rotation;\n"
"attribute vec4 pos;\n"
"attribute vec4 color;\n"
"varying vec4 v_color;\n"
"void main() {\n"
" gl_Position = rotation * pos;\n"
" v_color = color;\n"
"}\n";
static const char *frag_shader_text =
"precision mediump float;\n"
"varying vec4 v_color;\n"
"void main() {\n"
" gl_FragColor = v_color;\n"
"}\n";
static int running = 1;
static void
init_egl(struct display *display, struct window *window)
{
static const struct {
char *extension, *entrypoint;
} swap_damage_ext_to_entrypoint[] = {
{
.extension = "EGL_EXT_swap_buffers_with_damage",
.entrypoint = "eglSwapBuffersWithDamageEXT",
},
{
.extension = "EGL_KHR_swap_buffers_with_damage",
.entrypoint = "eglSwapBuffersWithDamageKHR",
},
};
static const EGLint context_attribs[] = {
EGL_CONTEXT_CLIENT_VERSION, 2,
EGL_NONE
};
const char *extensions;
EGLint config_attribs[] = {
EGL_SURFACE_TYPE, EGL_WINDOW_BIT,
EGL_RED_SIZE, 1,
EGL_GREEN_SIZE, 1,
EGL_BLUE_SIZE, 1,
EGL_ALPHA_SIZE, 1,
EGL_RENDERABLE_TYPE, EGL_OPENGL_ES2_BIT,
EGL_NONE
};
EGLint major, minor, n, count, i, size;
EGLConfig *configs;
EGLBoolean ret;
if (window->opaque || window->buffer_size == 16)
config_attribs[9] = 0;
display->egl.dpy =
weston_platform_get_egl_display(EGL_PLATFORM_WAYLAND_KHR,
display->display, NULL);
assert(display->egl.dpy);
ret = eglInitialize(display->egl.dpy, &major, &minor);
assert(ret == EGL_TRUE);
ret = eglBindAPI(EGL_OPENGL_ES_API);
assert(ret == EGL_TRUE);
if (!eglGetConfigs(display->egl.dpy, NULL, 0, &count) || count < 1)
assert(0);
configs = calloc(count, sizeof *configs);
assert(configs);
ret = eglChooseConfig(display->egl.dpy, config_attribs,
configs, count, &n);
assert(ret && n >= 1);
for (i = 0; i < n; i++) {
eglGetConfigAttrib(display->egl.dpy,
configs[i], EGL_BUFFER_SIZE, &size);
if (window->buffer_size == size) {
display->egl.conf = configs[i];
break;
}
}
free(configs);
if (display->egl.conf == NULL) {
fprintf(stderr, "did not find config with buffer size %d\n",
window->buffer_size);
exit(EXIT_FAILURE);
}
display->egl.ctx = eglCreateContext(display->egl.dpy,
display->egl.conf,
EGL_NO_CONTEXT, context_attribs);
assert(display->egl.ctx);
display->swap_buffers_with_damage = NULL;
extensions = eglQueryString(display->egl.dpy, EGL_EXTENSIONS);
if (extensions &&
weston_check_egl_extension(extensions, "EGL_EXT_buffer_age")) {
for (i = 0; i < (int) ARRAY_LENGTH(swap_damage_ext_to_entrypoint); i++) {
if (weston_check_egl_extension(extensions,
swap_damage_ext_to_entrypoint[i].extension)) {
/* The EXTPROC is identical to the KHR one */
display->swap_buffers_with_damage =
(PFNEGLSWAPBUFFERSWITHDAMAGEEXTPROC)
eglGetProcAddress(swap_damage_ext_to_entrypoint[i].entrypoint);
break;
}
}
}
if (display->swap_buffers_with_damage)
printf("has EGL_EXT_buffer_age and %s\n", swap_damage_ext_to_entrypoint[i].extension);
}
static void
fini_egl(struct display *display)
{
eglTerminate(display->egl.dpy);
eglReleaseThread();
}
static GLuint
create_shader(struct window *window, const char *source, GLenum shader_type)
{
GLuint shader;
GLint status;
shader = glCreateShader(shader_type);
assert(shader != 0);
glShaderSource(shader, 1, (const char **) &source, NULL);
glCompileShader(shader);
glGetShaderiv(shader, GL_COMPILE_STATUS, &status);
if (!status) {
char log[1000];
GLsizei len;
glGetShaderInfoLog(shader, 1000, &len, log);
fprintf(stderr, "Error: compiling %s: %.*s\n",
shader_type == GL_VERTEX_SHADER ? "vertex" : "fragment",
len, log);
exit(1);
}
return shader;
}
static void
init_gl(struct window *window)
{
GLuint frag, vert;
GLuint program;
GLint status;
frag = create_shader(window, frag_shader_text, GL_FRAGMENT_SHADER);
vert = create_shader(window, vert_shader_text, GL_VERTEX_SHADER);
program = glCreateProgram();
glAttachShader(program, frag);
glAttachShader(program, vert);
glLinkProgram(program);
glGetProgramiv(program, GL_LINK_STATUS, &status);
if (!status) {
char log[1000];
GLsizei len;
glGetProgramInfoLog(program, 1000, &len, log);
fprintf(stderr, "Error: linking:\n%.*s\n", len, log);
exit(1);
}
glUseProgram(program);
window->gl.pos = 0;
window->gl.col = 1;
glBindAttribLocation(program, window->gl.pos, "pos");
glBindAttribLocation(program, window->gl.col, "color");
glLinkProgram(program);
window->gl.rotation_uniform =
glGetUniformLocation(program, "rotation");
}
static void
handle_surface_configure(void *data, struct xdg_surface *surface,
uint32_t serial)
{
struct window *window = data;
xdg_surface_ack_configure(surface, serial);
window->wait_for_configure = false;
}
static const struct xdg_surface_listener xdg_surface_listener = {
handle_surface_configure
};
static void
handle_toplevel_configure(void *data, struct xdg_toplevel *toplevel,
int32_t width, int32_t height,
struct wl_array *states)
{
struct window *window = data;
uint32_t *p;
window->fullscreen = 0;
window->maximized = 0;
wl_array_for_each(p, states) {
uint32_t state = *p;
switch (state) {
case XDG_TOPLEVEL_STATE_FULLSCREEN:
window->fullscreen = 1;
break;
case XDG_TOPLEVEL_STATE_MAXIMIZED:
window->maximized = 1;
break;
}
}
if (width > 0 && height > 0) {
if (!window->fullscreen && !window->maximized) {
window->window_size.width = width;
window->window_size.height = height;
}
window->geometry.width = width;
window->geometry.height = height;
} else if (!window->fullscreen && !window->maximized) {
window->geometry = window->window_size;
}
if (window->native)
wl_egl_window_resize(window->native,
window->geometry.width,
window->geometry.height, 0, 0);
}
static void
handle_toplevel_close(void *data, struct xdg_toplevel *xdg_toplevel)
{
running = 0;
}
static const struct xdg_toplevel_listener xdg_toplevel_listener = {
handle_toplevel_configure,
handle_toplevel_close,
};
static void
create_surface(struct window *window)
{
struct display *display = window->display;
EGLBoolean ret;
window->surface = wl_compositor_create_surface(display->compositor);
window->native =
wl_egl_window_create(window->surface,
window->geometry.width,
window->geometry.height);
window->egl_surface =
weston_platform_create_egl_surface(display->egl.dpy,
display->egl.conf,
window->native, NULL);
window->xdg_surface = xdg_wm_base_get_xdg_surface(display->wm_base,
window->surface);
xdg_surface_add_listener(window->xdg_surface,
&xdg_surface_listener, window);
window->xdg_toplevel =
xdg_surface_get_toplevel(window->xdg_surface);
xdg_toplevel_add_listener(window->xdg_toplevel,
&xdg_toplevel_listener, window);
xdg_toplevel_set_title(window->xdg_toplevel, "simple-egl");
window->wait_for_configure = true;
wl_surface_commit(window->surface);
ret = eglMakeCurrent(window->display->egl.dpy, window->egl_surface,
window->egl_surface, window->display->egl.ctx);
assert(ret == EGL_TRUE);
if (!window->frame_sync)
eglSwapInterval(display->egl.dpy, 0);
if (!display->wm_base)
return;
if (window->fullscreen)
xdg_toplevel_set_fullscreen(window->xdg_toplevel, NULL);
}
static void
destroy_surface(struct window *window)
{
/* Required, otherwise segfault in egl_dri2.c: dri2_make_current()
* on eglReleaseThread(). */
eglMakeCurrent(window->display->egl.dpy, EGL_NO_SURFACE, EGL_NO_SURFACE,
EGL_NO_CONTEXT);
weston_platform_destroy_egl_surface(window->display->egl.dpy,
window->egl_surface);
wl_egl_window_destroy(window->native);
if (window->xdg_toplevel)
xdg_toplevel_destroy(window->xdg_toplevel);
if (window->xdg_surface)
xdg_surface_destroy(window->xdg_surface);
wl_surface_destroy(window->surface);
if (window->callback)
wl_callback_destroy(window->callback);
}
static void
redraw(void *data, struct wl_callback *callback, uint32_t time)
{
struct window *window = data;
struct display *display = window->display;
static const GLfloat verts[3][2] = {
{ -0.5, -0.5 },
{ 0.5, -0.5 },
{ 0, 0.5 }
};
static const GLfloat colors[3][3] = {
{ 1, 0, 0 },
{ 0, 1, 0 },
{ 0, 0, 1 }
};
GLfloat angle;
GLfloat rotation[4][4] = {
{ 1, 0, 0, 0 },
{ 0, 1, 0, 0 },
{ 0, 0, 1, 0 },
{ 0, 0, 0, 1 }
};
static const uint32_t speed_div = 5, benchmark_interval = 5;
struct wl_region *region;
EGLint rect[4];
EGLint buffer_age = 0;
struct timeval tv;
assert(window->callback == callback);
window->callback = NULL;
if (callback)
wl_callback_destroy(callback);
gettimeofday(&tv, NULL);
time = tv.tv_sec * 1000 + tv.tv_usec / 1000;
if (window->frames == 0)
window->benchmark_time = time;
if (time - window->benchmark_time > (benchmark_interval * 1000)) {
printf("%d frames in %d seconds: %f fps\n",
window->frames,
benchmark_interval,
(float) window->frames / benchmark_interval);
window->benchmark_time = time;
window->frames = 0;
}
angle = (time / speed_div) % 360 * M_PI / 180.0;
rotation[0][0] = cos(angle);
rotation[0][2] = sin(angle);
rotation[2][0] = -sin(angle);
rotation[2][2] = cos(angle);
if (display->swap_buffers_with_damage)
eglQuerySurface(display->egl.dpy, window->egl_surface,
EGL_BUFFER_AGE_EXT, &buffer_age);
glViewport(0, 0, window->geometry.width, window->geometry.height);
glUniformMatrix4fv(window->gl.rotation_uniform, 1, GL_FALSE,
(GLfloat *) rotation);
glClearColor(0.0, 0.0, 0.0, 0.5);
glClear(GL_COLOR_BUFFER_BIT);
glVertexAttribPointer(window->gl.pos, 2, GL_FLOAT, GL_FALSE, 0, verts);
glVertexAttribPointer(window->gl.col, 3, GL_FLOAT, GL_FALSE, 0, colors);
glEnableVertexAttribArray(window->gl.pos);
glEnableVertexAttribArray(window->gl.col);
glDrawArrays(GL_TRIANGLES, 0, 3);
glDisableVertexAttribArray(window->gl.pos);
glDisableVertexAttribArray(window->gl.col);
usleep(window->delay);
if (window->opaque || window->fullscreen) {
region = wl_compositor_create_region(window->display->compositor);
wl_region_add(region, 0, 0,
window->geometry.width,
window->geometry.height);
wl_surface_set_opaque_region(window->surface, region);
wl_region_destroy(region);
} else {
wl_surface_set_opaque_region(window->surface, NULL);
}
if (display->swap_buffers_with_damage && buffer_age > 0) {
rect[0] = window->geometry.width / 4 - 1;
rect[1] = window->geometry.height / 4 - 1;
rect[2] = window->geometry.width / 2 + 2;
rect[3] = window->geometry.height / 2 + 2;
display->swap_buffers_with_damage(display->egl.dpy,
window->egl_surface,
rect, 1);
} else {
eglSwapBuffers(display->egl.dpy, window->egl_surface);
}
window->frames++;
}
static void
pointer_handle_enter(void *data, struct wl_pointer *pointer,
uint32_t serial, struct wl_surface *surface,
wl_fixed_t sx, wl_fixed_t sy)
{
struct display *display = data;
struct wl_buffer *buffer;
struct wl_cursor *cursor = display->default_cursor;
struct wl_cursor_image *image;
if (display->window->fullscreen)
wl_pointer_set_cursor(pointer, serial, NULL, 0, 0);
else if (cursor) {
image = display->default_cursor->images[0];
buffer = wl_cursor_image_get_buffer(image);
if (!buffer)
return;
wl_pointer_set_cursor(pointer, serial,
display->cursor_surface,
image->hotspot_x,
image->hotspot_y);
wl_surface_attach(display->cursor_surface, buffer, 0, 0);
wl_surface_damage(display->cursor_surface, 0, 0,
image->width, image->height);
wl_surface_commit(display->cursor_surface);
}
}
static void
pointer_handle_leave(void *data, struct wl_pointer *pointer,
uint32_t serial, struct wl_surface *surface)
{
}
static void
pointer_handle_motion(void *data, struct wl_pointer *pointer,
uint32_t time, wl_fixed_t sx, wl_fixed_t sy)
{
}
static void
pointer_handle_button(void *data, struct wl_pointer *wl_pointer,
uint32_t serial, uint32_t time, uint32_t button,
uint32_t state)
{
struct display *display = data;
if (!display->window->xdg_toplevel)
return;
if (button == BTN_LEFT && state == WL_POINTER_BUTTON_STATE_PRESSED)
xdg_toplevel_move(display->window->xdg_toplevel,
display->seat, serial);
}
static void
pointer_handle_axis(void *data, struct wl_pointer *wl_pointer,
uint32_t time, uint32_t axis, wl_fixed_t value)
{
}
static const struct wl_pointer_listener pointer_listener = {
pointer_handle_enter,
pointer_handle_leave,
pointer_handle_motion,
pointer_handle_button,
pointer_handle_axis,
};
static void
touch_handle_down(void *data, struct wl_touch *wl_touch,
uint32_t serial, uint32_t time, struct wl_surface *surface,
int32_t id, wl_fixed_t x_w, wl_fixed_t y_w)
{
struct display *d = (struct display *)data;
if (!d->wm_base)
return;
xdg_toplevel_move(d->window->xdg_toplevel, d->seat, serial);
}
static void
touch_handle_up(void *data, struct wl_touch *wl_touch,
uint32_t serial, uint32_t time, int32_t id)
{
}
static void
touch_handle_motion(void *data, struct wl_touch *wl_touch,
uint32_t time, int32_t id, wl_fixed_t x_w, wl_fixed_t y_w)
{
}
static void
touch_handle_frame(void *data, struct wl_touch *wl_touch)
{
}
static void
touch_handle_cancel(void *data, struct wl_touch *wl_touch)
{
}
static const struct wl_touch_listener touch_listener = {
touch_handle_down,
touch_handle_up,
touch_handle_motion,
touch_handle_frame,
touch_handle_cancel,
};
static void
keyboard_handle_keymap(void *data, struct wl_keyboard *keyboard,
uint32_t format, int fd, uint32_t size)
{
/* Just so we don’t leak the keymap fd */
close(fd);
}
static void
keyboard_handle_enter(void *data, struct wl_keyboard *keyboard,
uint32_t serial, struct wl_surface *surface,
struct wl_array *keys)
{
}
static void
keyboard_handle_leave(void *data, struct wl_keyboard *keyboard,
uint32_t serial, struct wl_surface *surface)
{
}
static void
keyboard_handle_key(void *data, struct wl_keyboard *keyboard,
uint32_t serial, uint32_t time, uint32_t key,
uint32_t state)
{
struct display *d = data;
if (!d->wm_base)
return;
if (key == KEY_F11 && state) {
if (d->window->fullscreen)
xdg_toplevel_unset_fullscreen(d->window->xdg_toplevel);
else
xdg_toplevel_set_fullscreen(d->window->xdg_toplevel, NULL);
} else if (key == KEY_ESC && state)
running = 0;
}
static void
keyboard_handle_modifiers(void *data, struct wl_keyboard *keyboard,
uint32_t serial, uint32_t mods_depressed,
uint32_t mods_latched, uint32_t mods_locked,
uint32_t group)
{
}
static const struct wl_keyboard_listener keyboard_listener = {
keyboard_handle_keymap,
keyboard_handle_enter,
keyboard_handle_leave,
keyboard_handle_key,
keyboard_handle_modifiers,
};
static void
seat_handle_capabilities(void *data, struct wl_seat *seat,
enum wl_seat_capability caps)
{
struct display *d = data;
if ((caps & WL_SEAT_CAPABILITY_POINTER) && !d->pointer) {
d->pointer = wl_seat_get_pointer(seat);
wl_pointer_add_listener(d->pointer, &pointer_listener, d);
} else if (!(caps & WL_SEAT_CAPABILITY_POINTER) && d->pointer) {
wl_pointer_destroy(d->pointer);
d->pointer = NULL;
}
if ((caps & WL_SEAT_CAPABILITY_KEYBOARD) && !d->keyboard) {
d->keyboard = wl_seat_get_keyboard(seat);
wl_keyboard_add_listener(d->keyboard, &keyboard_listener, d);
} else if (!(caps & WL_SEAT_CAPABILITY_KEYBOARD) && d->keyboard) {
wl_keyboard_destroy(d->keyboard);
d->keyboard = NULL;
}
if ((caps & WL_SEAT_CAPABILITY_TOUCH) && !d->touch) {
d->touch = wl_seat_get_touch(seat);
wl_touch_set_user_data(d->touch, d);
wl_touch_add_listener(d->touch, &touch_listener, d);
} else if (!(caps & WL_SEAT_CAPABILITY_TOUCH) && d->touch) {
wl_touch_destroy(d->touch);
d->touch = NULL;
}
}
static const struct wl_seat_listener seat_listener = {
seat_handle_capabilities,
};
static void
xdg_wm_base_ping(void *data, struct xdg_wm_base *shell, uint32_t serial)
{
xdg_wm_base_pong(shell, serial);
}
static const struct xdg_wm_base_listener wm_base_listener = {
xdg_wm_base_ping,
};
static void
registry_handle_global(void *data, struct wl_registry *registry,
uint32_t name, const char *interface, uint32_t version)
{
struct display *d = data;
if (strcmp(interface, "wl_compositor") == 0) {
d->compositor =
wl_registry_bind(registry, name,
&wl_compositor_interface,
MIN(version, 4));
} else if (strcmp(interface, "xdg_wm_base") == 0) {
d->wm_base = wl_registry_bind(registry, name,
&xdg_wm_base_interface, 1);
xdg_wm_base_add_listener(d->wm_base, &wm_base_listener, d);
} else if (strcmp(interface, "wl_seat") == 0) {
d->seat = wl_registry_bind(registry, name,
&wl_seat_interface, 1);
wl_seat_add_listener(d->seat, &seat_listener, d);
} else if (strcmp(interface, "wl_shm") == 0) {
d->shm = wl_registry_bind(registry, name,
&wl_shm_interface, 1);
d->cursor_theme = wl_cursor_theme_load(NULL, 32, d->shm);
if (!d->cursor_theme) {
fprintf(stderr, "unable to load default theme\n");
return;
}
d->default_cursor =
wl_cursor_theme_get_cursor(d->cursor_theme, "left_ptr");
if (!d->default_cursor) {
fprintf(stderr, "unable to load default left pointer\n");
// TODO: abort ?
}
}
}
static void
registry_handle_global_remove(void *data, struct wl_registry *registry,
uint32_t name)
{
}
static const struct wl_registry_listener registry_listener = {
registry_handle_global,
registry_handle_global_remove
};
static void
signal_int(int signum)
{
running = 0;
}
static void
usage(int error_code)
{
fprintf(stderr, "Usage: simple-egl [OPTIONS]\n\n"
" -d <us>\tBuffer swap delay in microseconds\n"
" -f\tRun in fullscreen mode\n"
" -o\tCreate an opaque surface\n"
" -s\tUse a 16 bpp EGL config\n"
" -b\tDon't sync to compositor redraw (eglSwapInterval 0)\n"
" -h\tThis help text\n\n");
exit(error_code);
}
int
main(int argc, char **argv)
{
struct sigaction sigint;
struct display display = { 0 };
struct window window = { 0 };
int i, ret = 0;
window.display = &display;
display.window = &window;
window.geometry.width = 250;
window.geometry.height = 250;
window.window_size = window.geometry;
window.buffer_size = 32;
window.frame_sync = 1;
window.delay = 0;
for (i = 1; i < argc; i++) {
if (strcmp("-d", argv[i]) == 0 && i+1 < argc)
window.delay = atoi(argv[++i]);
else if (strcmp("-f", argv[i]) == 0)
window.fullscreen = 1;
else if (strcmp("-o", argv[i]) == 0)
window.opaque = 1;
else if (strcmp("-s", argv[i]) == 0)
window.buffer_size = 16;
else if (strcmp("-b", argv[i]) == 0)
window.frame_sync = 0;
else if (strcmp("-h", argv[i]) == 0)
usage(EXIT_SUCCESS);
else
usage(EXIT_FAILURE);
}
display.display = wl_display_connect(NULL);
assert(display.display);
display.registry = wl_display_get_registry(display.display);
wl_registry_add_listener(display.registry,
®istry_listener, &display);
wl_display_roundtrip(display.display);
init_egl(&display, &window);
create_surface(&window);
init_gl(&window);
display.cursor_surface =
wl_compositor_create_surface(display.compositor);
sigint.sa_handler = signal_int;
sigemptyset(&sigint.sa_mask);
sigint.sa_flags = SA_RESETHAND;
sigaction(SIGINT, &sigint, NULL);
/* The mainloop here is a little subtle. Redrawing will cause
* EGL to read events so we can just call
* wl_display_dispatch_pending() to handle any events that got
* queued up as a side effect. */
while (running && ret != -1) {
if (window.wait_for_configure) {
ret = wl_display_dispatch(display.display);
} else {
ret = wl_display_dispatch_pending(display.display);
redraw(&window, NULL, 0);
}
}
fprintf(stderr, "simple-egl exiting\n");
destroy_surface(&window);
fini_egl(&display);
wl_surface_destroy(display.cursor_surface);
if (display.cursor_theme)
wl_cursor_theme_destroy(display.cursor_theme);
if (display.wm_base)
xdg_wm_base_destroy(display.wm_base);
if (display.compositor)
wl_compositor_destroy(display.compositor);
wl_registry_destroy(display.registry);
wl_display_flush(display.display);
wl_display_disconnect(display.display);
return 0;
}
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