--- /dev/null
+/*
+ * Copyright (C) 2008 Brian Paul All Rights Reserved.
+ *
+ * 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 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
+ * BRIAN PAUL 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.
+ */
+
+/*
+ * Draw a triangle with X/EGL.
+ * Brian Paul
+ * 3 June 2008
+ */
+
+
+#include <assert.h>
+#include <math.h>
+#include <stdlib.h>
+#include <stdio.h>
+#include <string.h>
+#include <X11/Xlib.h>
+#include <X11/Xutil.h>
+#include <X11/keysym.h>
+#include <GL/gl.h> /* using full OpenGL for now */
+#include <GLES/egl.h>
+
+
+static GLfloat view_rotx = 0.0, view_roty = 0.0, view_rotz = 0.0;
+
+
+static void
+draw(void)
+{
+ static const GLfloat verts[3][2] = {
+ { -1, -1 },
+ { 1, -1 },
+ { 0, 1 }
+ };
+ static const GLfloat colors[3][3] = {
+ { 1, 0, 0 },
+ { 0, 1, 0 },
+ { 0, 0, 1 }
+ };
+
+ glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
+
+ glPushMatrix();
+ glRotatef(view_rotx, 1, 0, 0);
+ glRotatef(view_roty, 0, 1, 0);
+ glRotatef(view_rotz, 0, 0, 1);
+
+ {
+ glVertexPointer(2, GL_FLOAT, 0, verts);
+ glColorPointer(3, GL_FLOAT, 0, colors);
+ glEnableClientState(GL_VERTEX_ARRAY);
+ glEnableClientState(GL_COLOR_ARRAY);
+
+ glDrawArrays(GL_TRIANGLES, 0, 3);
+
+ glDisableClientState(GL_VERTEX_ARRAY);
+ glDisableClientState(GL_COLOR_ARRAY);
+ }
+
+ glPopMatrix();
+}
+
+
+/* new window size or exposure */
+static void
+reshape(int width, int height)
+{
+ GLfloat ar = (GLfloat) width / (GLfloat) height;
+
+ glViewport(0, 0, (GLint) width, (GLint) height);
+
+ glMatrixMode(GL_PROJECTION);
+ glLoadIdentity();
+ glFrustum(-ar, ar, -1, 1, 5.0, 60.0);
+
+ glMatrixMode(GL_MODELVIEW);
+ glLoadIdentity();
+ glTranslatef(0.0, 0.0, -10.0);
+}
+
+
+static void
+init(void)
+{
+ glClearColor(0.4, 0.4, 0.4, 0.0);
+}
+
+
+/*
+ * Create an RGB, double-buffered X window.
+ * Return the window and context handles.
+ */
+static void
+make_x_window(Display *x_dpy, EGLDisplay egl_dpy,
+ const char *name,
+ int x, int y, int width, int height,
+ Window *winRet,
+ EGLContext *ctxRet,
+ EGLSurface *surfRet)
+{
+ static const EGLint attribs[] = {
+ EGL_RED_SIZE, 1,
+ EGL_GREEN_SIZE, 1,
+ EGL_BLUE_SIZE, 1,
+ EGL_DEPTH_SIZE, 1,
+ EGL_NONE
+ };
+
+ int scrnum;
+ XSetWindowAttributes attr;
+ unsigned long mask;
+ Window root;
+ Window win;
+ XVisualInfo *visInfo, visTemplate;
+ int num_visuals;
+ EGLContext ctx;
+ EGLConfig config;
+ EGLint num_configs;
+ EGLint vid;
+
+ scrnum = DefaultScreen( x_dpy );
+ root = RootWindow( x_dpy, scrnum );
+
+ if (!eglChooseConfig( egl_dpy, attribs, &config, 1, &num_configs)) {
+ printf("Error: couldn't get an EGL visual config\n");
+ exit(1);
+ }
+
+ assert(config);
+ assert(num_configs > 0);
+
+ if (!eglGetConfigAttrib(egl_dpy, config, EGL_NATIVE_VISUAL_ID, &vid)) {
+ printf("Error: eglGetConfigAttrib() failed\n");
+ exit(1);
+ }
+
+ /* The X window visual must match the EGL config */
+ visTemplate.visualid = vid;
+ visInfo = XGetVisualInfo(x_dpy, VisualIDMask, &visTemplate, &num_visuals);
+ if (!visInfo) {
+ printf("Error: couldn't get X visual\n");
+ exit(1);
+ }
+
+ /* window attributes */
+ attr.background_pixel = 0;
+ attr.border_pixel = 0;
+ attr.colormap = XCreateColormap( x_dpy, root, visInfo->visual, AllocNone);
+ attr.event_mask = StructureNotifyMask | ExposureMask | KeyPressMask;
+ mask = CWBackPixel | CWBorderPixel | CWColormap | CWEventMask;
+
+ win = XCreateWindow( x_dpy, root, 0, 0, width, height,
+ 0, visInfo->depth, InputOutput,
+ visInfo->visual, mask, &attr );
+
+ /* set hints and properties */
+ {
+ XSizeHints sizehints;
+ sizehints.x = x;
+ sizehints.y = y;
+ sizehints.width = width;
+ sizehints.height = height;
+ sizehints.flags = USSize | USPosition;
+ XSetNormalHints(x_dpy, win, &sizehints);
+ XSetStandardProperties(x_dpy, win, name, name,
+ None, (char **)NULL, 0, &sizehints);
+ }
+
+ eglBindAPI(EGL_OPENGL_API);
+
+ ctx = eglCreateContext(egl_dpy, config, EGL_NO_CONTEXT, NULL );
+ if (!ctx) {
+ printf("Error: glXCreateContext failed\n");
+ exit(1);
+ }
+
+ *surfRet = eglCreateWindowSurface(egl_dpy, config, win, NULL);
+
+ if (!*surfRet) {
+ printf("Error: eglCreateWindowSurface failed\n");
+ exit(1);
+ }
+
+ XFree(visInfo);
+
+ *winRet = win;
+ *ctxRet = ctx;
+}
+
+
+static void
+event_loop(Display *dpy, Window win,
+ EGLDisplay egl_dpy, EGLSurface egl_surf)
+{
+ while (1) {
+ int redraw = 0;
+ XEvent event;
+
+ XNextEvent(dpy, &event);
+
+ switch (event.type) {
+ case Expose:
+ redraw = 1;
+ break;
+ case ConfigureNotify:
+ reshape(event.xconfigure.width, event.xconfigure.height);
+ break;
+ case KeyPress:
+ {
+ char buffer[10];
+ int r, code;
+ code = XLookupKeysym(&event.xkey, 0);
+ if (code == XK_Left) {
+ view_roty += 5.0;
+ }
+ else if (code == XK_Right) {
+ view_roty -= 5.0;
+ }
+ else if (code == XK_Up) {
+ view_rotx += 5.0;
+ }
+ else if (code == XK_Down) {
+ view_rotx -= 5.0;
+ }
+ else {
+ r = XLookupString(&event.xkey, buffer, sizeof(buffer),
+ NULL, NULL);
+ if (buffer[0] == 27) {
+ /* escape */
+ return;
+ }
+ }
+ }
+ redraw = 1;
+ break;
+ default:
+ ; /*no-op*/
+ }
+
+ if (redraw) {
+ draw();
+ eglSwapBuffers(egl_dpy, egl_surf);
+ }
+ }
+}
+
+
+static void
+usage(void)
+{
+ printf("Usage:\n");
+ printf(" -display <displayname> set the display to run on\n");
+ printf(" -info display OpenGL renderer info\n");
+}
+
+
+int
+main(int argc, char *argv[])
+{
+ const int winWidth = 300, winHeight = 300;
+ Display *x_dpy;
+ Window win;
+ EGLSurface egl_surf;
+ EGLContext egl_ctx;
+ EGLDisplay egl_dpy;
+ char *dpyName = NULL;
+ GLboolean printInfo = GL_FALSE;
+ EGLint egl_major, egl_minor;
+ int i;
+ const char *s;
+
+ for (i = 1; i < argc; i++) {
+ if (strcmp(argv[i], "-display") == 0) {
+ dpyName = argv[i+1];
+ i++;
+ }
+ else if (strcmp(argv[i], "-info") == 0) {
+ printInfo = GL_TRUE;
+ }
+ else {
+ usage();
+ return -1;
+ }
+ }
+
+ x_dpy = XOpenDisplay(dpyName);
+ if (!x_dpy) {
+ printf("Error: couldn't open display %s\n",
+ dpyName ? dpyName : getenv("DISPLAY"));
+ return -1;
+ }
+
+ egl_dpy = eglGetDisplay(x_dpy);
+ if (!egl_dpy) {
+ printf("Error: eglGetDisplay() failed\n");
+ return -1;
+ }
+
+ if (!eglInitialize(egl_dpy, &egl_major, &egl_minor)) {
+ printf("Error: eglInitialize() failed\n");
+ return -1;
+ }
+
+ s = eglQueryString(egl_dpy, EGL_VERSION);
+ printf("EGL_VERSION = %s\n", s);
+
+ make_x_window(x_dpy, egl_dpy,
+ "xegl_tri", 0, 0, winWidth, winHeight,
+ &win, &egl_ctx, &egl_surf);
+
+ XMapWindow(x_dpy, win);
+ if (!eglMakeCurrent(egl_dpy, egl_surf, egl_surf, egl_ctx)) {
+ printf("Error: eglMakeCurrent() failed\n");
+ return -1;
+ }
+
+ if (printInfo) {
+ printf("GL_RENDERER = %s\n", (char *) glGetString(GL_RENDERER));
+ printf("GL_VERSION = %s\n", (char *) glGetString(GL_VERSION));
+ printf("GL_VENDOR = %s\n", (char *) glGetString(GL_VENDOR));
+ }
+
+ init();
+
+ /* Set initial projection/viewing transformation.
+ * We can't be sure we'll get a ConfigureNotify event when the window
+ * first appears.
+ */
+ reshape(winWidth, winHeight);
+
+ event_loop(x_dpy, win, egl_dpy, egl_surf);
+
+ eglDestroyContext(egl_dpy, egl_ctx);
+ eglDestroySurface(egl_dpy, egl_surf);
+ eglTerminate(egl_dpy);
+
+
+ XDestroyWindow(x_dpy, win);
+ XCloseDisplay(x_dpy);
+
+ return 0;
+}