--- /dev/null
+/*
+ * Copyright © 2011 Benjamin Franzke
+ *
+ * Permission to use, copy, modify, distribute, and sell this software and its
+ * documentation for any purpose is hereby granted without fee, provided that
+ * the above copyright notice appear in all copies and that both that copyright
+ * notice and this permission notice appear in supporting documentation, and
+ * that the name of the copyright holders not be used in advertising or
+ * publicity pertaining to distribution of the software without specific,
+ * written prior permission. The copyright holders make no representations
+ * about the suitability of this software for any purpose. It is provided "as
+ * is" without express or implied warranty.
+ *
+ * THE COPYRIGHT HOLDERS DISCLAIM ALL WARRANTIES WITH REGARD TO THIS SOFTWARE,
+ * INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS, IN NO
+ * EVENT SHALL THE COPYRIGHT HOLDERS BE LIABLE FOR ANY SPECIAL, INDIRECT OR
+ * CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE,
+ * DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER
+ * TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE
+ * OF THIS SOFTWARE.
+ */
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <stddef.h>
+#include <stdint.h>
+#include <stdbool.h>
+#include <math.h>
+#include <assert.h>
+
+#include <fcntl.h>
+
+#include <wayland-client.h>
+#include <xf86drm.h>
+
+#define GL_GLEXT_PROTOTYPES
+#define EGL_EGLEXT_PROTOTYPES
+#include <GLES2/gl2.h>
+#include <GLES2/gl2ext.h>
+#include <EGL/egl.h>
+#include <EGL/eglext.h>
+
+struct display {
+ struct wl_display *display;
+ struct {
+ struct wl_compositor *compositor;
+ struct wl_drm *drm;
+ } interface;
+ struct {
+ EGLDisplay dpy;
+ EGLContext ctx;
+ } egl;
+ struct {
+ int fd;
+ const char *device_name;
+ bool authenticated;
+ } drm;
+ uint32_t mask;
+};
+
+struct window {
+ struct display *display;
+ struct {
+ int width, height;
+ } geometry;
+ struct {
+ GLuint fbo;
+ GLuint color_rbo;
+
+ GLuint program;
+ GLuint rotation_uniform;
+
+ GLuint pos;
+ GLuint col;
+ } gl;
+ struct {
+ struct wl_buffer *buffer;
+ struct wl_surface *surface;
+ EGLImageKHR image;
+ } drm_surface;
+};
+
+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 =
+ "varying vec4 v_color;\n"
+ "void main() {\n"
+ " gl_FragColor = v_color;\n"
+ "}\n";
+
+static void
+init_egl(struct display *display)
+{
+ EGLint major, minor;
+ EGLBoolean ret;
+
+ display->egl.dpy = eglGetDRMDisplayMESA(display->drm.fd);
+ assert(display->egl.dpy);
+
+ ret = eglInitialize(display->egl.dpy, &major, &minor);
+ assert(ret == EGL_TRUE);
+ ret = eglBindAPI(EGL_OPENGL_API);
+ assert(ret == EGL_TRUE);
+
+ display->egl.ctx = eglCreateContext(display->egl.dpy, NULL,
+ EGL_NO_CONTEXT, NULL);
+ assert(display->egl.ctx);
+ ret = eglMakeCurrent(display->egl.dpy, NULL, NULL, display->egl.ctx);
+ assert(ret == EGL_TRUE);
+}
+
+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)
+{
+ GLfloat ar;
+ GLuint frag, vert;
+ GLint status;
+
+ glGenFramebuffers(1, &window->gl.fbo);
+ glBindFramebuffer(GL_FRAMEBUFFER, window->gl.fbo);
+
+ glGenRenderbuffers(1, &window->gl.color_rbo);
+
+ glViewport(0, 0, window->geometry.width, window->geometry.height);
+ ar = (GLfloat)window->geometry.width / (GLfloat)window->geometry.height;
+
+ frag = create_shader(window, frag_shader_text, GL_FRAGMENT_SHADER);
+ vert = create_shader(window, vert_shader_text, GL_VERTEX_SHADER);
+
+ window->gl.program = glCreateProgram();
+ glAttachShader(window->gl.program, frag);
+ glAttachShader(window->gl.program, vert);
+ glLinkProgram(window->gl.program);
+
+ glGetProgramiv(window->gl.program, GL_LINK_STATUS, &status);
+ if (!status) {
+ char log[1000];
+ GLsizei len;
+ glGetProgramInfoLog(window->gl.program, 1000, &len, log);
+ fprintf(stderr, "Error: linking:\n%*s\n", len, log);
+ exit(1);
+ }
+
+ glUseProgram(window->gl.program);
+
+ window->gl.pos = 0;
+ window->gl.pos = 1;
+
+ glBindAttribLocation(window->gl.program, window->gl.pos, "pos");
+ glBindAttribLocation(window->gl.program, window->gl.col, "color");
+ glLinkProgram(window->gl.program);
+
+ window->gl.rotation_uniform =
+ glGetUniformLocation(window->gl.program, "rotation");
+}
+
+static void
+create_surface(struct window *window)
+{
+ struct display *display = window->display;
+ struct wl_visual *visual;
+ EGLint name, stride;
+ EGLint image_attribs[] = {
+ EGL_WIDTH, 0,
+ EGL_HEIGHT, 0,
+ EGL_DRM_BUFFER_FORMAT_MESA, EGL_DRM_BUFFER_FORMAT_ARGB32_MESA,
+ EGL_DRM_BUFFER_USE_MESA, EGL_DRM_BUFFER_USE_SCANOUT_MESA,
+ EGL_NONE
+ };
+
+ window->drm_surface.surface =
+ wl_compositor_create_surface(display->interface.compositor);
+
+ image_attribs[1] = window->geometry.width;
+ image_attribs[3] = window->geometry.height;
+
+ window->drm_surface.image = eglCreateDRMImageMESA(display->egl.dpy,
+ image_attribs);
+ eglExportDRMImageMESA(display->egl.dpy, window->drm_surface.image,
+ &name, NULL, &stride);
+ visual = wl_display_get_premultiplied_argb_visual(display->display);
+
+ window->drm_surface.buffer =
+ wl_drm_create_buffer(display->interface.drm, name,
+ window->geometry.width,
+ window->geometry.height,
+ stride, visual);
+ /* Process wl_drm_create_buffer. */
+ wl_display_iterate(display->display, WL_DISPLAY_WRITABLE);
+
+ wl_surface_attach(window->drm_surface.surface,
+ window->drm_surface.buffer, 0, 0);
+ wl_surface_map_toplevel(window->drm_surface.surface);
+
+ glBindRenderbuffer(GL_RENDERBUFFER, window->gl.color_rbo);
+ glEGLImageTargetRenderbufferStorageOES(GL_RENDERBUFFER,
+ window->drm_surface.image);
+
+ glFramebufferRenderbuffer(GL_FRAMEBUFFER,
+ GL_COLOR_ATTACHMENT0,
+ GL_RENDERBUFFER,
+ window->gl.color_rbo);
+
+ assert(glCheckFramebufferStatus(GL_FRAMEBUFFER) ==
+ GL_FRAMEBUFFER_COMPLETE);
+}
+
+static void
+redraw(void *data, uint32_t time)
+{
+ struct window *window = data;
+ 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 int32_t speed_div = 5;
+ static uint32_t start_time = 0;
+
+ if (start_time == 0)
+ start_time = time;
+
+ angle = ((time-start_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);
+
+ 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);
+
+ glFlush();
+
+ wl_surface_damage(window->drm_surface.surface, 0, 0,
+ window->geometry.width, window->geometry.height);
+
+ wl_display_frame_callback(window->display->display, redraw, window);
+}
+
+static void
+drm_handle_device(void *data, struct wl_drm *drm, const char *device)
+{
+ struct display *d = data;
+
+ d->drm.device_name = strdup(device);
+}
+
+static void
+drm_handle_authenticated(void *data, struct wl_drm *drm)
+{
+ struct display *d = data;
+
+ d->drm.authenticated = true;
+}
+
+static const struct wl_drm_listener drm_listener = {
+ drm_handle_device,
+ drm_handle_authenticated
+};
+
+static void
+display_handle_global(struct wl_display *display, uint32_t id,
+ const char *interface, uint32_t version, void *data)
+{
+ struct display *d = data;
+
+ if (strcmp(interface, "compositor") == 0) {
+ d->interface.compositor = wl_compositor_create(display, id);
+ } else if (strcmp(interface, "drm") == 0) {
+ d->interface.drm = wl_drm_create(display, id);
+ wl_drm_add_listener(d->interface.drm, &drm_listener, d);
+ }
+}
+
+static int
+event_mask_update(uint32_t mask, void *data)
+{
+ struct display *d = data;
+
+ d->mask = mask;
+
+ return 0;
+}
+
+int
+main(int argc, char **argv)
+{
+ struct display display = { 0 };
+ struct window window = { 0 };
+ drm_magic_t magic;
+ int ret;
+
+ memset(&display, 0, sizeof display);
+ memset(&window, 0, sizeof window);
+
+ window.display = &display;
+ window.geometry.width = 250;
+ window.geometry.height = 250;
+
+ display.display = wl_display_connect(NULL);
+ assert(display.display);
+
+ wl_display_add_global_listener(display.display,
+ display_handle_global, &display);
+ /* process connection events */
+ wl_display_iterate(display.display, WL_DISPLAY_READABLE);
+
+ display.drm.fd = open(display.drm.device_name, O_RDWR);
+ assert(display.drm.fd >= 0);
+
+ ret = drmGetMagic(display.drm.fd, &magic);
+ assert(ret == 0);
+ wl_drm_authenticate(display.interface.drm, magic);
+ wl_display_iterate(display.display, WL_DISPLAY_WRITABLE);
+ while (!display.drm.authenticated)
+ wl_display_iterate(display.display, WL_DISPLAY_READABLE);
+
+ init_egl(&display);
+ init_gl(&window);
+ create_surface(&window);
+
+ wl_display_frame_callback(display.display, redraw, &window);
+
+ wl_display_get_fd(display.display, event_mask_update, &display);
+ while (true)
+ wl_display_iterate(display.display, display.mask);
+
+ return 0;
+}