+/**************************************************************************
+ *
+ * Copyright 2008 Tungsten Graphics, Inc., Cedar Park, Texas.
+ * All Rights Reserved.
+ *
+ **************************************************************************/
+
+/*
+ * Draw a triangle with X/EGL and OpenGL ES 2.x
+ */
+
+#define USE_FULL_GL 1
+
+
+
+#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>
+#if USE_FULL_GL
+#include <GL/gl.h> /* use full OpenGL */
+#else
+#include <GLES2/gl2.h> /* use OpenGL ES 2.x */
+#endif
+#include <EGL/egl.h>
+
+
+#define FLOAT_TO_FIXED(X) ((X) * 65535.0)
+
+
+
+static GLfloat view_rotx = 0.0, view_roty = 0.0;
+
+static GLint u_matrix = -1;
+static GLint attr_pos = 0, attr_color = 1;
+
+
+static void
+make_z_rot_matrix(GLfloat angle, GLfloat *m)
+{
+ float c = cos(angle * M_PI / 180.0);
+ float s = sin(angle * M_PI / 180.0);
+ int i;
+ for (i = 0; i < 16; i++)
+ m[i] = 0.0;
+ m[0] = m[5] = m[10] = m[15] = 1.0;
+
+ m[0] = c;
+ m[1] = s;
+ m[4] = -s;
+ m[5] = c;
+}
+
+static void
+make_scale_matrix(GLfloat xs, GLfloat ys, GLfloat zs, GLfloat *m)
+{
+ int i;
+ for (i = 0; i < 16; i++)
+ m[i] = 0.0;
+ m[0] = xs;
+ m[5] = ys;
+ m[10] = zs;
+ m[15] = 1.0;
+}
+
+
+static void
+mul_matrix(GLfloat *prod, const GLfloat *a, const GLfloat *b)
+{
+#define A(row,col) a[(col<<2)+row]
+#define B(row,col) b[(col<<2)+row]
+#define P(row,col) p[(col<<2)+row]
+ GLfloat p[16];
+ GLint i;
+ for (i = 0; i < 4; i++) {
+ const GLfloat ai0=A(i,0), ai1=A(i,1), ai2=A(i,2), ai3=A(i,3);
+ P(i,0) = ai0 * B(0,0) + ai1 * B(1,0) + ai2 * B(2,0) + ai3 * B(3,0);
+ P(i,1) = ai0 * B(0,1) + ai1 * B(1,1) + ai2 * B(2,1) + ai3 * B(3,1);
+ P(i,2) = ai0 * B(0,2) + ai1 * B(1,2) + ai2 * B(2,2) + ai3 * B(3,2);
+ P(i,3) = ai0 * B(0,3) + ai1 * B(1,3) + ai2 * B(2,3) + ai3 * B(3,3);
+ }
+ memcpy(prod, p, sizeof(p));
+#undef A
+#undef B
+#undef PROD
+}
+
+
+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 }
+ };
+ GLfloat mat[16], rot[16], scale[16];
+
+ /* Set modelview/projection matrix */
+ make_z_rot_matrix(view_rotx, rot);
+ make_scale_matrix(0.5, 0.5, 0.5, scale);
+ mul_matrix(mat, rot, scale);
+ glUniformMatrix4fv(u_matrix, 1, GL_FALSE, mat);
+
+ glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
+
+ {
+ glVertexAttribPointer(attr_pos, 2, GL_FLOAT, GL_FALSE, 0, verts);
+ glVertexAttribPointer(attr_color, 3, GL_FLOAT, GL_FALSE, 0, colors);
+ glEnableVertexAttribArray(attr_pos);
+ glEnableVertexAttribArray(attr_color);
+
+ glDrawArrays(GL_TRIANGLES, 0, 3);
+
+ glDisableVertexAttribArray(attr_pos);
+ glDisableVertexAttribArray(attr_color);
+ }
+}
+
+
+/* new window size or exposure */
+static void
+reshape(int width, int height)
+{
+ glViewport(0, 0, (GLint) width, (GLint) height);
+}
+
+
+static void
+create_shaders(void)
+{
+ static const char *fragShaderText =
+ "varying vec4 v_color;\n"
+ "void main() {\n"
+ " gl_FragColor = v_color;\n"
+ "}\n";
+ static const char *vertShaderText =
+ "uniform mat4 modelviewProjection;\n"
+ "attribute vec4 pos;\n"
+ "attribute vec4 color;\n"
+ "varying vec4 v_color;\n"
+ "void main() {\n"
+ " gl_Position = modelviewProjection * pos;\n"
+ " v_color = color;\n"
+ "}\n";
+
+ GLuint fragShader, vertShader, program;
+ GLint stat;
+
+ fragShader = glCreateShader(GL_FRAGMENT_SHADER);
+ glShaderSource(fragShader, 1, (const char **) &fragShaderText, NULL);
+ glCompileShader(fragShader);
+ glGetShaderiv(fragShader, GL_COMPILE_STATUS, &stat);
+ if (!stat) {
+ printf("Error: fragment shader did not compile!\n");
+ exit(1);
+ }
+
+ vertShader = glCreateShader(GL_VERTEX_SHADER);
+ glShaderSource(vertShader, 1, (const char **) &vertShaderText, NULL);
+ glCompileShader(vertShader);
+ glGetShaderiv(vertShader, GL_COMPILE_STATUS, &stat);
+ if (!stat) {
+ printf("Error: vertex shader did not compile!\n");
+ exit(1);
+ }
+
+ program = glCreateProgram();
+ glAttachShader(program, fragShader);
+ glAttachShader(program, vertShader);
+ glLinkProgram(program);
+
+ glGetProgramiv(program, GL_LINK_STATUS, &stat);
+ if (!stat) {
+ char log[1000];
+ GLsizei len;
+ glGetProgramInfoLog(program, 1000, &len, log);
+ printf("Error: linking:\n%s\n", log);
+ exit(1);
+ }
+
+ glUseProgram(program);
+
+ if (1) {
+ /* test setting attrib locations */
+ glBindAttribLocation(program, attr_pos, "pos");
+ glBindAttribLocation(program, attr_color, "color");
+ glLinkProgram(program); /* needed to put attribs into effect */
+ }
+ else {
+ /* test automatic attrib locations */
+ attr_pos = glGetAttribLocation(program, "pos");
+ attr_color = glGetAttribLocation(program, "color");
+ }
+
+ u_matrix = glGetUniformLocation(program, "modelviewProjection");
+ printf("Uniform modelviewProjection at %d\n", u_matrix);
+ printf("Attrib pos at %d\n", attr_pos);
+ printf("Attrib color at %d\n", attr_color);
+}
+
+
+static void
+init(void)
+{
+ typedef void (*proc)();
+
+#if 1 /* test code */
+ proc p = eglGetProcAddress("glMapBufferOES");
+ assert(p);
+#endif
+
+ glClearColor(0.4, 0.4, 0.4, 0.0);
+
+ create_shaders();
+}
+
+
+/*
+ * 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_RENDERABLE_TYPE, EGL_OPENGL_ES2_BIT,
+ EGL_NONE
+ };
+#if USE_FULL_GL
+ static const EGLint ctx_attribs[] = {
+ EGL_NONE
+ };
+#else
+ static const EGLint ctx_attribs[] = {
+ EGL_CONTEXT_CLIENT_VERSION, 2,
+ EGL_NONE
+ };
+#endif
+
+ 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);
+ }
+
+#if USE_FULL_GL /* XXX fix this when eglBindAPI() works */
+ eglBindAPI(EGL_OPENGL_API);
+#else
+ eglBindAPI(EGL_OPENGL_ES_API);
+#endif
+
+ ctx = eglCreateContext(egl_dpy, config, EGL_NO_CONTEXT, ctx_attribs );
+ if (!ctx) {
+ printf("Error: eglCreateContext failed\n");
+ exit(1);
+ }
+
+#if !USE_FULL_GL
+ /* test eglQueryContext() */
+ {
+ EGLint val;
+ eglQueryContext(egl_dpy, ctx, EGL_CONTEXT_CLIENT_VERSION, &val);
+ assert(val == 2);
+ }
+#endif
+
+ *surfRet = eglCreateWindowSurface(egl_dpy, config, win, NULL);
+ if (!*surfRet) {
+ printf("Error: eglCreateWindowSurface failed\n");
+ exit(1);
+ }
+
+ /* sanity checks */
+ {
+ EGLint val;
+ eglQuerySurface(egl_dpy, *surfRet, EGL_WIDTH, &val);
+ assert(val == width);
+ eglQuerySurface(egl_dpy, *surfRet, EGL_HEIGHT, &val);
+ assert(val == height);
+ assert(eglGetConfigAttrib(egl_dpy, config, EGL_SURFACE_TYPE, &val));
+ assert(val & EGL_WINDOW_BIT);
+ }
+
+ 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);
+ exit(0);
+ }
+ }
+}
+
+
+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);
+
+ s = eglQueryString(egl_dpy, EGL_VENDOR);
+ printf("EGL_VENDOR = %s\n", s);
+
+ s = eglQueryString(egl_dpy, EGL_EXTENSIONS);
+ printf("EGL_EXTENSIONS = %s\n", s);
+
+ s = eglQueryString(egl_dpy, EGL_CLIENT_APIS);
+ printf("EGL_CLIENT_APIS = %s\n", s);
+
+ make_x_window(x_dpy, egl_dpy,
+ "OpenGL ES 2.x 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));
+ printf("GL_EXTENSIONS = %s\n", (char *) glGetString(GL_EXTENSIONS));
+ }
+
+ 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;
+}