source/main.c

   1 #define GL_GLEXT_PROTOTYPES
   2 #include <stdio.h>
   3 #include <stdlib.h>
   4 #include <string.h>
   5 #include <signal.h>
   6 #include <math.h>
   7 #include <X11/Xlib.h>
   8 #include <X11/Xatom.h>
   9 #include <X11/extensions/Xcomposite.h>
  10 #include <X11/extensions/Xdamage.h>
  11 #include <X11/extensions/shape.h>
  12 #include <X11/extensions/Xrandr.h>
  13 #include <GL/gl.h>
  14 #include <GL/glx.h>
  15
  16 typedef struct CompositedWindow
  17 {
  18         Window window;
  19         int x;
  20         int y;
  21         unsigned width;
  22         unsigned height;
  23         unsigned border;
  24         int map_state;
  25         Damage damage;
  26         Pixmap pixmap;
  27         GLXPixmap glx_pixmap;
  28         int recreate_pixmap;
  29         unsigned texture;
  30         unsigned mask_texture;
  31         int use_mask;
  32         int recreate_mask;
  33 } CompositedWindow;
  34
  35 typedef struct CompositedMonitor
  36 {
  37         char *name;
  38         int enabled;
  39         int x;
  40         int y;
  41         unsigned width;
  42         unsigned height;
  43         float keystone_vertical;
  44         float cylinder_depth;
  45         float vertical_center;
  46         float perspective;
  47         unsigned vertex_buffer;
  48         unsigned index_buffer;
  49         unsigned vertex_array;
  50         unsigned tessellation;
  51         unsigned nelements;
  52 } CompositedMonitor;
  53
  54 typedef struct CompositedScreen
  55 {
  56         int number;
  57         Window root;
  58         unsigned width;
  59         unsigned height;
  60         Window overlay;
  61         Window render_window;
  62         GLXFBConfig fbconfig;
  63         GLXWindow glx_window;
  64         GLXContext glx_context;
  65         unsigned shaders[3];
  66         unsigned program;
  67         int geometry_loc;
  68         unsigned masked_program;
  69         int masked_geometry_loc;
  70         unsigned window_vertex_buffer;
  71         unsigned window_vertex_array;
  72         unsigned framebuffer;
  73         unsigned fb_texture;
  74         CompositedWindow *windows;
  75         unsigned nwindows;
  76         unsigned windows_capacity;
  77         CompositedMonitor *monitors;
  78         unsigned nmonitors;
  79         int dirty;
  80 } CompositedScreen;
  81
  82 typedef struct Compositor
  83 {
  84         Display *display;
  85         CompositedScreen *screens;
  86         unsigned nscreens;
  87         int damage_event;
  88         int shape_event;
  89         PFNGLXCREATECONTEXTATTRIBSARBPROC glXCreateContextAttribsARB;
  90         PFNGLXBINDTEXIMAGEEXTPROC glXBindTexImageEXT;
  91         PFNGLXRELEASETEXIMAGEEXTPROC glXReleaseTexImageEXT;
  92         Atom correction_atom;
  93         Atom monitors_atom;
  94         int dirty;
  95 } Compositor;
  96
  97 static const char *vshader_src =
  98         "#version 150\n"
  99         "uniform vec4 geometry;\n"
 100         "in vec2 vertex;\n"
 101         "in vec2 texture_coord;\n"
 102         "out vec2 texcoord;\n"
 103         "void main()\n"
 104         "{\n"
 105         "  gl_Position = vec4((geometry.xy+vertex*geometry.zw)*2.0-1.0, 0.0, 1.0);\n"
 106         "  texcoord = texture_coord;\n"
 107         "}\n";
 108
 109 static const char *fshader_src =
 110         "#version 150\n"
 111         "uniform sampler2D image;\n"
 112         "in vec2 texcoord;\n"
 113         "out vec4 frag_color;\n"
 114         "void main()\n"
 115         "{\n"
 116         "  frag_color = texture(image, texcoord);\n"
 117         "}\n";
 118
 119 static const char *masked_fshader_src =
 120         "#version 150\n"
 121         "uniform sampler2D image;\n"
 122         "uniform sampler2D mask;\n"
 123         "in vec2 texcoord;\n"
 124         "out vec4 frag_color;\n"
 125         "void main()\n"
 126         "{\n"
 127         "  if(texture(mask, texcoord).r==0.0)\n"
 128         "    discard;\n"
 129         "  frag_color = texture(image, texcoord);\n"
 130         "}\n";
 131
 132 static const float window_vertices[] =
 133 {
 134         /* vertex    texcoord */
 135         0.0f, 1.0f,  0.0f, 0.0f,
 136         0.0f, 0.0f,  0.0f, 1.0f,
 137         1.0f, 1.0f,  1.0f, 0.0f,
 138         1.0f, 0.0f,  1.0f, 1.0f
 139 };
 140
 141 int terminate_requested = 0;
 142
 143 int x_error_handler(Display *display, XErrorEvent *event)
 144 {
 145         printf("Ignoring X error %d on resource %lx\n", event->error_code, event->resourceid);
 146         (void)display;
 147         return 0;
 148 }
 149
 150 int with_error(const char *message)
 151 {
 152         fprintf(stderr, "%s\n", message);
 153         return 0;
 154 }
 155
 156 int initialize_gl(Compositor *compositor, CompositedScreen *screen)
 157 {
 158         int attribs[9];
 159         unsigned i;
 160         GLXFBConfig *configs;
 161         int nconfigs;
 162         XVisualInfo *vi;
 163         XSetWindowAttributes win_attr;
 164
 165         i = 0;
 166         attribs[i++] = GLX_DRAWABLE_TYPE;
 167         attribs[i++] = GLX_WINDOW_BIT;
 168         attribs[i++] = GLX_RENDER_TYPE;
 169         attribs[i++] = GLX_RGBA_BIT;
 170         attribs[i++] = GLX_DOUBLEBUFFER;
 171         attribs[i++] = True;
 172         attribs[i++] = GLX_BIND_TO_TEXTURE_RGBA_EXT;
 173         attribs[i++] = True;
 174         attribs[i] = None;
 175
 176         configs = glXChooseFBConfig(compositor->display, screen->number, attribs, &nconfigs);
 177         if(!configs || !nconfigs)
 178                 return with_error("Could not find a suitable FBConfig");
 179         screen->fbconfig = configs[0];
 180         XFree(configs);
 181
 182         vi = glXGetVisualFromFBConfig(compositor->display, screen->fbconfig);
 183         win_attr.colormap = XCreateColormap(compositor->display, screen->root, vi->visual, AllocNone);
 184         screen->render_window = XCreateWindow(compositor->display, screen->overlay, 0, 0, screen->width, screen->height, 0, vi->depth, InputOutput, vi->visual, CWColormap, &win_attr);
 185         XMapWindow(compositor->display, screen->render_window);
 186
 187         screen->glx_window = glXCreateWindow(compositor->display, screen->fbconfig, screen->render_window, NULL);
 188
 189         i = 0;
 190         attribs[i++] = GLX_CONTEXT_FLAGS_ARB;
 191         attribs[i++] = GLX_CONTEXT_FORWARD_COMPATIBLE_BIT_ARB;
 192         attribs[i++] = GLX_CONTEXT_MAJOR_VERSION_ARB;
 193         attribs[i++] = 3;
 194         attribs[i++] = GLX_CONTEXT_MINOR_VERSION_ARB;
 195         attribs[i++] = 1;
 196         attribs[i] = None;
 197
 198         screen->glx_context = compositor->glXCreateContextAttribsARB(compositor->display, screen->fbconfig, NULL, True, attribs);
 199
 200         XFree(vi);
 201
 202         return 1;
 203 }
 204
 205 void use_gl(Compositor *compositor, CompositedScreen *screen)
 206 {
 207         glXMakeContextCurrent(compositor->display, screen->glx_window, screen->glx_window, screen->glx_context);
 208 }
 209
 210 unsigned compile_shader(GLenum type, const char *source)
 211 {
 212         unsigned shader;
 213         int status;
 214         char info_log[1024];
 215         GLsizei length;
 216
 217         shader = glCreateShader(type);
 218         glShaderSource(shader, 1, &source, NULL);
 219         glCompileShader(shader);
 220         glGetShaderiv(shader, GL_COMPILE_STATUS, &status);
 221         glGetShaderInfoLog(shader, sizeof(info_log), &length, info_log);
 222         if(!status)
 223         {
 224                 fprintf(stderr, "Shader compilation failed:\n%s\n", info_log);
 225                 glDeleteShader(shader);
 226                 return 0;
 227         }
 228         else if(length)
 229                 printf("Shader info log:\n%s\n", info_log);
 230
 231         return shader;
 232 }
 233
 234 unsigned link_program(unsigned vshader, unsigned fshader)
 235 {
 236         unsigned program;
 237         int status;
 238         char info_log[1024];
 239         GLsizei length;
 240
 241         program = glCreateProgram();
 242         glAttachShader(program, vshader);
 243         glAttachShader(program, fshader);
 244         glBindAttribLocation(program, 0, "vertex");
 245         glBindAttribLocation(program, 1, "texture_coord");
 246         glBindFragDataLocation(program, 0, "frag_color");
 247         glLinkProgram(program);
 248
 249         glGetProgramiv(program, GL_LINK_STATUS, &status);
 250         glGetProgramInfoLog(program, sizeof(info_log), &length, info_log);
 251         if(!status)
 252         {
 253                 fprintf(stderr, "Program link failed:\n%s\n", info_log);
 254                 glDeleteProgram(program);
 255                 return 0;
 256         }
 257         else if(length)
 258                 printf("Program info log:\n%s\n", info_log);
 259
 260         return program;
 261 }
 262
 263 unsigned create_2d_texture()
 264 {
 265         unsigned texture;
 266         glGenTextures(1, &texture);
 267         glBindTexture(GL_TEXTURE_2D, texture);
 268         glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR);
 269         glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_CLAMP_TO_EDGE);
 270         glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_CLAMP_TO_EDGE);
 271         return texture;
 272 }
 273
 274 int create_gl_resources(Compositor *compositor, CompositedScreen *screen)
 275 {
 276         unsigned stride;
 277         int loc;
 278
 279         use_gl(compositor, screen);
 280
 281         screen->shaders[0] = compile_shader(GL_VERTEX_SHADER, vshader_src);
 282         screen->shaders[1] = compile_shader(GL_FRAGMENT_SHADER, fshader_src);
 283         screen->shaders[2] = compile_shader(GL_FRAGMENT_SHADER, masked_fshader_src);
 284         if(!screen->shaders[0] || !screen->shaders[1] || !screen->shaders[2])
 285                 return 0;
 286
 287         screen->program = link_program(screen->shaders[0], screen->shaders[1]);
 288         if(!screen->program)
 289                 return 0;
 290
 291         screen->masked_program = link_program(screen->shaders[0], screen->shaders[2]);
 292         if(!screen->masked_program)
 293                 return 0;
 294
 295         screen->geometry_loc = glGetUniformLocation(screen->program, "geometry");
 296         screen->masked_geometry_loc = glGetUniformLocation(screen->masked_program, "geometry");
 297
 298         loc = glGetUniformLocation(screen->masked_program, "mask");
 299         if(loc>=0)
 300         {
 301                 glUseProgram(screen->masked_program);
 302                 glUniform1i(loc, 1);
 303         }
 304
 305         glGenBuffers(1, &screen->window_vertex_buffer);
 306         glBindBuffer(GL_ARRAY_BUFFER, screen->window_vertex_buffer);
 307         glBufferData(GL_ARRAY_BUFFER, sizeof(window_vertices), window_vertices, GL_STATIC_DRAW);
 308
 309         stride = 4*sizeof(float);
 310         glGenVertexArrays(1, &screen->window_vertex_array);
 311         glBindVertexArray(screen->window_vertex_array);
 312         glVertexAttribPointer(0, 2, GL_FLOAT, GL_FALSE, stride, NULL);
 313         glEnableVertexAttribArray(0);
 314         glVertexAttribPointer(1, 2, GL_FLOAT, GL_FALSE, stride, (void *)(2*sizeof(float)));
 315         glEnableVertexAttribArray(1);
 316         glBindVertexArray(0);
 317
 318         glBindBuffer(GL_ARRAY_BUFFER, 0);
 319
 320         screen->fb_texture = create_2d_texture();
 321         glTexImage2D(GL_TEXTURE_2D, 0, GL_RGB8, screen->width, screen->height, 0, GL_RGB, GL_UNSIGNED_BYTE, NULL);
 322         glBindTexture(GL_TEXTURE_2D, 0);
 323
 324         glGenFramebuffers(1, &screen->framebuffer);
 325         glBindFramebuffer(GL_DRAW_FRAMEBUFFER, screen->framebuffer);
 326         glFramebufferTexture2D(GL_DRAW_FRAMEBUFFER, GL_COLOR_ATTACHMENT0, GL_TEXTURE_2D, screen->fb_texture, 0);
 327         glDepthMask(GL_FALSE);
 328         glBindFramebuffer(GL_DRAW_FRAMEBUFFER, 0);
 329
 330         return 1;
 331 }
 332
 333 CompositedWindow *find_window(CompositedScreen *screen, Window w)
 334 {
 335         unsigned i;
 336
 337         for(i=0; i<screen->nwindows; ++i)
 338                 if(screen->windows[i].window==w)
 339                         return &screen->windows[i];
 340
 341         return NULL;
 342 }
 343
 344 CompositedWindow *find_window_global(Compositor *compositor, Window w, CompositedScreen **screen)
 345 {
 346         unsigned i, j;
 347
 348         for(i=0; i<compositor->nscreens; ++i)
 349                 for(j=0; j<compositor->screens[i].nwindows; ++j)
 350                         if(compositor->screens[i].windows[j].window==w)
 351                         {
 352                                 if(screen)
 353                                         *screen = &compositor->screens[i];
 354                                 return &compositor->screens[i].windows[j];
 355                         }
 356
 357         if(screen)
 358                 *screen = NULL;
 359         return NULL;
 360 }
 361
 362 void create_window_pixmap(Compositor *compositor, CompositedScreen *screen, CompositedWindow *window)
 363 {
 364         int attribs[5];
 365         unsigned i;
 366
 367         if(window->pixmap)
 368         {
 369                 glXDestroyPixmap(compositor->display, window->glx_pixmap);
 370                 XFreePixmap(compositor->display, window->pixmap);
 371         }
 372
 373         i = 0;
 374         attribs[i++] = GLX_TEXTURE_TARGET_EXT;
 375         attribs[i++] = GLX_TEXTURE_2D_EXT;
 376         attribs[i++] = GLX_TEXTURE_FORMAT_EXT;
 377         attribs[i++] = GLX_TEXTURE_FORMAT_RGBA_EXT;
 378         attribs[i++] = None;
 379
 380         window->pixmap = XCompositeNameWindowPixmap(compositor->display, window->window);
 381         window->glx_pixmap = glXCreatePixmap(compositor->display, screen->fbconfig, window->pixmap, attribs);
 382         window->recreate_pixmap = 0;
 383 }
 384
 385 void update_window_mask(Compositor *compositor, CompositedWindow *window)
 386 {
 387         Bool bounding_shaped;
 388         Bool clip_shaped;
 389         int xi, yi;
 390         XRectangle *rects;
 391         int rect_count;
 392         int rect_order;
 393         unsigned width;
 394         unsigned height;
 395         unsigned char *data;
 396         int i;
 397         unsigned y;
 398
 399         XShapeQueryExtents(compositor->display, window->window, &bounding_shaped, &xi, &yi, &width, &height, &clip_shaped, &xi, &yi, &width, &height);
 400         window->use_mask = bounding_shaped;
 401         if(!window->use_mask)
 402                 return;
 403
 404         rects = XShapeGetRectangles(compositor->display, window->window, ShapeBounding, &rect_count, &rect_order);
 405
 406         width = window->width+2*window->border;
 407         height = window->height+2*window->border;
 408         data = (unsigned char *)malloc(width*height);
 409         memset(data, 0, width*height);
 410         for(i=0; i<rect_count; ++i)
 411         {
 412                 rects[i].x += window->border;
 413                 rects[i].y += window->border;
 414                 if(rects[i].x>=(int)width || rects[i].y>=(int)height)
 415                         continue;
 416
 417                 if(rects[i].x<0)
 418                 {
 419                         if(-rects[i].x>rects[i].width)
 420                                 continue;
 421                         rects[i].width += rects[i].x;
 422                         rects[i].x = 0;
 423                 }
 424
 425                 if(rects[i].y<0)
 426                 {
 427                         if(-rects[i].y>rects[i].height)
 428                                 continue;
 429                         rects[i].height += rects[i].y;
 430                         rects[i].y = 0;
 431                 }
 432
 433                 if(rects[i].x+rects[i].width>(int)width)
 434                         rects[i].width = width-rects[i].x;
 435                 if(rects[i].y+rects[i].height>(int)height)
 436                         rects[i].height = height-rects[i].y;
 437
 438                 for(y=0; y<rects[i].height; ++y)
 439                 {
 440                         unsigned char *row = data+(rects[i].y+y)*width+rects[i].x;
 441                         memset(row, 255, rects[i].width);
 442                 }
 443         }
 444
 445         XFree(rects);
 446
 447         glBindTexture(GL_TEXTURE_2D, window->mask_texture);
 448         glPixelStorei(GL_UNPACK_ALIGNMENT, 1);
 449         glTexImage2D(GL_TEXTURE_2D, 0, GL_R8, width, height, 0, GL_RED, GL_UNSIGNED_BYTE, data);
 450
 451         free(data);
 452
 453         window->recreate_mask = 0;
 454 }
 455
 456 CompositedWindow *add_window(Compositor *compositor, CompositedScreen *screen, Window w)
 457 {
 458         CompositedWindow *window;
 459         XWindowAttributes win_attr;
 460
 461         if(w==screen->root || w==screen->overlay)
 462                 return NULL;
 463
 464         if(!XGetWindowAttributes(compositor->display, w, &win_attr))
 465         {
 466                 printf("XGetWindowAttributes failed; probably the window was already destroyed\n");
 467                 return NULL;
 468         }
 469         if(win_attr.class==InputOnly)
 470                 return NULL;
 471
 472         if(find_window(screen, w))
 473                 return NULL;
 474
 475         if(screen->nwindows==screen->windows_capacity)
 476         {
 477                 screen->windows = (CompositedWindow *)realloc(screen->windows, (screen->windows_capacity+1)*sizeof(CompositedWindow));
 478                 ++screen->windows_capacity;
 479         }
 480
 481         window = &screen->windows[screen->nwindows++];
 482
 483         window->window = w;
 484         window->x = win_attr.x;
 485         window->y = win_attr.y;
 486         window->width = win_attr.width;
 487         window->height = win_attr.height;
 488         window->border = win_attr.border_width;
 489         window->map_state = win_attr.map_state;
 490
 491         window->damage = XDamageCreate(compositor->display, window->window, XDamageReportNonEmpty);
 492         window->pixmap = None;
 493         window->glx_pixmap = None;
 494
 495         XCompositeRedirectWindow(compositor->display, window->window, CompositeRedirectManual);
 496         window->recreate_pixmap = (window->map_state==IsViewable);
 497
 498         window->texture = create_2d_texture();
 499         window->mask_texture = create_2d_texture();
 500         window->recreate_mask = (window->map_state==IsViewable);
 501
 502         XShapeSelectInput(compositor->display, window->window, ShapeNotifyMask);
 503
 504         return window;
 505 }
 506
 507 void remove_window(Compositor *compositor, CompositedScreen *screen, CompositedWindow *window, int destroyed)
 508 {
 509         unsigned i;
 510
 511         glDeleteTextures(1, &window->texture);
 512         if(!destroyed)
 513         {
 514                 XDamageDestroy(compositor->display, window->damage);
 515                 if(window->pixmap)
 516                 {
 517                         glXDestroyPixmap(compositor->display, window->glx_pixmap);
 518                         XFreePixmap(compositor->display, window->pixmap);
 519                 }
 520                 XCompositeUnredirectWindow(compositor->display, window->window, CompositeRedirectManual);
 521         }
 522
 523         --screen->nwindows;
 524         for(i=window-screen->windows; i<screen->nwindows; ++i)
 525                 screen->windows[i] = screen->windows[i+1];
 526 }
 527
 528 CompositedWindow *reorder_window(CompositedScreen *screen, CompositedWindow *window, Window above)
 529 {
 530         unsigned i, j;
 531         CompositedWindow hold;
 532
 533         i = window-screen->windows;
 534         if(above)
 535         {
 536                 for(j=0; j<screen->nwindows; ++j)
 537                         if(screen->windows[j].window==above)
 538                                 break;
 539
 540                 if(j>=screen->nwindows || i==j+1)
 541                         return window;
 542
 543                 if(j<i)
 544                         ++j;
 545         }
 546         else
 547                 j = 0;
 548
 549         hold = *window;
 550         if(i<j)
 551         {
 552                 for(; i<j; ++i)
 553                         screen->windows[i] = screen->windows[i+1];
 554         }
 555         else
 556         {
 557                 for(; i>j; --i)
 558                         screen->windows[i] = screen->windows[i-1];
 559         }
 560         screen->windows[j] = hold;
 561
 562         return &screen->windows[j];
 563 }
 564
 565 CompositedScreen *find_screen_by_root(Compositor *compositor, Window root)
 566 {
 567         unsigned i;
 568
 569         for(i=0; i<compositor->nscreens; ++i)
 570                 if(compositor->screens[i].root==root)
 571                         return &compositor->screens[i];
 572
 573         return NULL;
 574 }
 575
 576 void update_monitor_vertices(CompositedScreen *screen, CompositedMonitor *monitor)
 577 {
 578         unsigned t;
 579         unsigned data_size;
 580         float *vertex_data;
 581         unsigned short *index_data;
 582         unsigned x, y;
 583         unsigned i;
 584         float aspect;
 585         float cyl_radius;
 586         float cyl_arc;
 587         float sin_ksv;
 588         float cos_ksv;
 589         float distance;
 590         float eye[3];
 591         float look[3];
 592
 593         t = monitor->tessellation;
 594
 595         data_size = (t+1)*(t+1)*4*sizeof(float);
 596         vertex_data = (float *)malloc(data_size);
 597
 598         aspect = (float)monitor->width/monitor->height;
 599
 600         if(monitor->cylinder_depth)
 601         {
 602                 cyl_radius = (monitor->cylinder_depth*monitor->cylinder_depth+0.25f)/(2.0f*monitor->cylinder_depth);
 603                 cyl_arc = 2.0f*asin(0.5f/cyl_radius);
 604         }
 605
 606         sin_ksv = monitor->keystone_vertical/sqrt(1.0f+monitor->keystone_vertical*monitor->keystone_vertical);
 607         cos_ksv = sqrt(1.0f-sin_ksv*sin_ksv);
 608         distance = monitor->perspective+sin_ksv*((sin_ksv>0)-monitor->vertical_center)/aspect;
 609
 610         eye[0] = 0.0f;
 611         eye[1] = (monitor->vertical_center-0.5f)/aspect+sin_ksv*distance;
 612         eye[2] = cos_ksv*distance;
 613
 614         look[0] = 0.0f;
 615         look[1] = -sin_ksv;
 616         look[2] = -cos_ksv;
 617
 618         for(y=0; y<=t; ++y)
 619                 for(x=0; x<=t; ++x)
 620                 {
 621                         float *v;
 622
 623                         v = vertex_data+(y*(t+1)+x)*3;
 624                         v[0] = (float)x/t-0.5f;
 625                         v[1] = ((float)y/t-0.5f)/aspect;
 626                         v[2] = 0;
 627                         if(monitor->cylinder_depth)
 628                         {
 629                                 v[2] = (1.0f-cos(v[0]*cyl_arc))*cyl_radius-monitor->cylinder_depth;
 630                                 v[0] = sin(v[0]*cyl_arc)*cyl_radius;
 631                         }
 632                 }
 633
 634         for(y=t; y<=t; --y)
 635                 for(x=t; x<=t; --x)
 636                 {
 637                         float *v;
 638                         float px, py, pz;
 639                         float scale;
 640
 641                         v = vertex_data+(y*(t+1)+x)*3;
 642                         px = v[0]-eye[0];
 643                         py = (v[0]-eye[0])*look[0] - (v[1]-eye[1])*look[2] + (v[2]-eye[2])*look[1];
 644                         pz = (v[0]-eye[0])*look[0] + (v[1]-eye[1])*look[1] + (v[2]-eye[2])*look[2];
 645                         scale = monitor->perspective/pz;
 646
 647                         v = vertex_data+(y*(t+1)+x)*4;
 648                         v[0] = px*scale+0.5f;
 649                         v[1] = py*aspect*scale+monitor->vertical_center;
 650                         v[2] = (monitor->x+(float)x*monitor->width/t)/screen->width;
 651                         v[3] = 1.0f-(monitor->y+(1.0f-(float)y/t)*monitor->height)/screen->height;
 652                 }
 653
 654         glBindBuffer(GL_ARRAY_BUFFER, monitor->vertex_buffer);
 655         glBufferData(GL_ARRAY_BUFFER, data_size, vertex_data, GL_STATIC_DRAW);
 656         glBindBuffer(GL_ARRAY_BUFFER, 0);
 657         free(vertex_data);
 658
 659         monitor->nelements = t*((t+1)*2+1)-1;
 660         data_size = monitor->nelements*sizeof(unsigned short);
 661         index_data = (unsigned short *)malloc(data_size);
 662         i = 0;
 663         for(y=0; y<t; ++y)
 664         {
 665                 if(y>0)
 666                         index_data[i++] = 0xFFFF;
 667                 for(x=0; x<=t; ++x)
 668                 {
 669                         index_data[i++] = (y+1)*(t+1)+x;
 670                         index_data[i++] = y*(t+1)+x;
 671                 }
 672         }
 673         glBindBuffer(GL_ELEMENT_ARRAY_BUFFER, monitor->index_buffer);
 674         glBufferData(GL_ELEMENT_ARRAY_BUFFER, data_size, index_data, GL_STATIC_DRAW);
 675         glBindBuffer(GL_ELEMENT_ARRAY_BUFFER, 0);
 676         free(index_data);
 677 }
 678
 679 int initialize_monitor(Compositor *compositor, CompositedScreen *screen, XRRScreenResources *xrr_res, unsigned index)
 680 {
 681         CompositedMonitor *monitor;
 682         XRROutputInfo *output;
 683         int namelen;
 684         XRRCrtcInfo *crtc;
 685         unsigned buffers[2];
 686         unsigned stride;
 687
 688         monitor = &screen->monitors[index];
 689
 690         output = XRRGetOutputInfo(compositor->display, xrr_res, xrr_res->outputs[index]);
 691         namelen = strlen(output->name);
 692         monitor->name = (char *)malloc(namelen+1);
 693         strcpy(monitor->name, output->name);
 694         monitor->enabled = !!output->crtc;
 695         if(!monitor->enabled)
 696         {
 697                 XRRFreeOutputInfo(output);
 698                 return 1;
 699         }
 700
 701         crtc = XRRGetCrtcInfo(compositor->display, xrr_res, output->crtc);
 702         monitor->x = crtc->x;
 703         monitor->y = crtc->y;
 704         monitor->width = crtc->width;
 705         monitor->height = crtc->height;
 706         XRRFreeCrtcInfo(crtc);
 707         XRRFreeOutputInfo(output);
 708
 709         monitor->keystone_vertical = 0.0f;
 710         monitor->cylinder_depth = 0.0f;
 711         monitor->vertical_center = 0.5f;
 712         monitor->perspective = 1.0f;
 713
 714         glGenBuffers(2, buffers);
 715         monitor->vertex_buffer = buffers[0];
 716         monitor->index_buffer = buffers[1];
 717
 718         monitor->tessellation = 50;
 719         update_monitor_vertices(screen, monitor);
 720         stride = 4*sizeof(float);
 721
 722         glGenVertexArrays(1, &monitor->vertex_array);
 723         glBindVertexArray(monitor->vertex_array);
 724         glBindBuffer(GL_ARRAY_BUFFER, monitor->vertex_buffer);
 725         glVertexAttribPointer(0, 2, GL_FLOAT, GL_FALSE, stride, NULL);
 726         glEnableVertexAttribArray(0);
 727         glVertexAttribPointer(1, 2, GL_FLOAT, GL_FALSE, stride, (void *)(2*sizeof(float)));
 728         glEnableVertexAttribArray(1);
 729         glBindBuffer(GL_ARRAY_BUFFER, 0);
 730         glBindBuffer(GL_ELEMENT_ARRAY_BUFFER, monitor->index_buffer);
 731         glBindVertexArray(0);
 732
 733         return 1;
 734 }
 735
 736 CompositedMonitor *find_monitor_by_name(CompositedScreen *screen, char *name)
 737 {
 738         unsigned i;
 739
 740         for(i=0; i<screen->nmonitors; ++i)
 741                 if(!strcmp(screen->monitors[i].name, name))
 742                         return &screen->monitors[i];
 743
 744         return NULL;
 745 }
 746
 747 void update_geometry_correction(Compositor *compositor, CompositedScreen *screen)
 748 {
 749         Atom prop_type;
 750         int prop_format;
 751         unsigned long overflow;
 752         unsigned long names_length;
 753         char *names;
 754         unsigned long values_length;
 755         short *values;
 756         char *name_ptr;
 757         unsigned i;
 758
 759         XGetWindowProperty(compositor->display, screen->root, compositor->monitors_atom, 0, 64, False, XA_STRING,
 760                 &prop_type, &prop_format, &names_length, &overflow, (unsigned char **)&names);
 761         if(prop_type!=XA_STRING || prop_format!=8)
 762                 return;
 763
 764         XGetWindowProperty(compositor->display, screen->root, compositor->correction_atom, 0, 64, False, XA_INTEGER,
 765                 &prop_type, &prop_format, &values_length, &overflow, (unsigned char **)&values);
 766         if(prop_type!=XA_INTEGER || prop_format!=16)
 767         {
 768                 XFree(names);
 769                 return;
 770         }
 771
 772         use_gl(compositor, screen);
 773
 774         name_ptr = names;
 775         for(i=0; i*4<values_length; ++i)
 776         {
 777                 CompositedMonitor *monitor;
 778
 779                 if(name_ptr>=names+names_length)
 780                         break;
 781
 782                 monitor = find_monitor_by_name(screen, name_ptr);
 783                 if(monitor)
 784                 {
 785                         monitor->keystone_vertical = values[i*4]/10000.0f;
 786                         monitor->cylinder_depth = values[i*4+1]/10000.0f;
 787                         monitor->vertical_center = values[i*4+2]/10000.0f;
 788                         monitor->perspective = values[i*4+3]/10000.0f;
 789
 790                         if(monitor->enabled)
 791                                 update_monitor_vertices(screen, monitor);
 792                 }
 793
 794                 name_ptr += strlen(name_ptr)+1;
 795         }
 796
 797         XFree(names);
 798         XFree(values);
 799 }
 800
 801 int initialize_screen(Compositor *compositor, unsigned number)
 802 {
 803         CompositedScreen *screen;
 804         const char *extensions;
 805         Window dummy_root;
 806         int x, y;
 807         unsigned border;
 808         unsigned depth;
 809         XRRScreenResources *xrr_res;
 810         Window dummy_parent;
 811         Window *children;
 812         unsigned nchildren;
 813         unsigned i;
 814
 815         screen = &compositor->screens[number];
 816         screen->number = number;
 817
 818         extensions = glXQueryExtensionsString(compositor->display, screen->number);
 819         if(!strstr(extensions, "GLX_ARB_create_context"))
 820                 return with_error("GLX_ARB_create_context is required");
 821         if(!strstr(extensions, "GLX_EXT_texture_from_pixmap"))
 822                 return with_error("GLX_EXT_texture_from_pixmap is required");
 823
 824         screen->root = RootWindow(compositor->display, screen->number);
 825         XSelectInput(compositor->display, screen->root, SubstructureNotifyMask|PropertyChangeMask);
 826         screen->overlay = XCompositeGetOverlayWindow(compositor->display, screen->root);
 827         XGetGeometry(compositor->display, screen->overlay, &dummy_root, &x, &y, &screen->width, &screen->height, &border, &depth);
 828         XShapeCombineRectangles(compositor->display, screen->overlay, ShapeInput, 0, 0, NULL, 0, ShapeSet, Unsorted);
 829
 830         if(!initialize_gl(compositor, screen))
 831                 return 0;
 832
 833         if(!create_gl_resources(compositor, screen))
 834                 return 0;
 835
 836         xrr_res = XRRGetScreenResources(compositor->display, screen->root);
 837         screen->nmonitors = xrr_res->noutput;
 838         screen->monitors = (CompositedMonitor *)malloc(screen->nmonitors*sizeof(CompositedMonitor));
 839         for(i=0; i<screen->nmonitors; ++i)
 840                 if(!initialize_monitor(compositor, screen, xrr_res, i))
 841                         return 0;
 842         XRRFreeScreenResources(xrr_res);
 843
 844         update_geometry_correction(compositor, screen);
 845
 846         XQueryTree(compositor->display, screen->root, &dummy_root, &dummy_parent, &children, &nchildren);
 847
 848         screen->windows = (CompositedWindow *)malloc(nchildren*sizeof(CompositedWindow));
 849         screen->nwindows = 0;
 850         screen->windows_capacity = nchildren;
 851
 852         for(i=0; i<nchildren; ++i)
 853                 add_window(compositor, screen, children[i]);
 854
 855         XFree(children);
 856
 857         screen->dirty = 1;
 858
 859         return 1;
 860 }
 861
 862 int initialize_compositor(Compositor *compositor)
 863 {
 864         int event_base;
 865         int error_base;
 866         int major_ver;
 867         int minor_ver;
 868         unsigned i;
 869
 870         compositor->display = XOpenDisplay(NULL);
 871         if(!compositor->display)
 872                 return with_error("Could not open X display");
 873
 874         XSetErrorHandler(&x_error_handler);
 875
 876         if(!XCompositeQueryExtension(compositor->display, &event_base, &error_base))
 877                 return with_error("XComposite is required but was not found");
 878         else if(!XCompositeQueryVersion(compositor->display, &major_ver, &minor_ver))
 879                 return with_error("Cannot determine XComposite version");
 880         else if(major_ver==0 && minor_ver<3)
 881                 return with_error("XComposite 0.3 or later is required");
 882
 883         if(!glXQueryExtension(compositor->display, &event_base, &error_base))
 884                 return with_error("GLX is required but was not found");
 885         else if(!glXQueryVersion(compositor->display, &major_ver, &minor_ver))
 886                 return with_error("Cannot determine GLX version");
 887         else if(major_ver<1 || (major_ver==1 && minor_ver<4))
 888                 return with_error("GLX 1.4 or later is required");
 889
 890         if(!XDamageQueryExtension(compositor->display, &compositor->damage_event, &error_base))
 891                 return with_error("XDamage is required but was not found");
 892         else if(!XDamageQueryVersion(compositor->display, &major_ver, &minor_ver))
 893                 return with_error("Cannot determine XDamage version");
 894         else if(major_ver<1)
 895                 return with_error("XDamage 1.0 or later is required");
 896
 897         if(!XShapeQueryExtension(compositor->display, &compositor->shape_event, &error_base))
 898                 return with_error("XShape is required but was not found");
 899         else if(!XShapeQueryVersion(compositor->display, &major_ver, &minor_ver))
 900                 return with_error("Cannot determine XShape version");
 901         else if(major_ver<1 || (major_ver==1 && minor_ver<1))
 902                 return with_error("XShape 1.1 or later is required");
 903
 904         if(!XRRQueryExtension(compositor->display, &event_base, &error_base))
 905                 return with_error("XRandR is required but was not found");
 906         else if(!XRRQueryVersion(compositor->display, &major_ver, &minor_ver))
 907                 return with_error("Cannot determine XRandR version");
 908         else if(major_ver<1 || (major_ver==1 && minor_ver<2))
 909                 return with_error("XRandR 1.2 or later is required");
 910
 911         compositor->glXCreateContextAttribsARB = (PFNGLXCREATECONTEXTATTRIBSARBPROC)glXGetProcAddress((unsigned char *)"glXCreateContextAttribsARB");
 912         compositor->glXBindTexImageEXT = (PFNGLXBINDTEXIMAGEEXTPROC)glXGetProcAddress((unsigned char *)"glXBindTexImageEXT");
 913         compositor->glXReleaseTexImageEXT = (PFNGLXRELEASETEXIMAGEEXTPROC)glXGetProcAddress((unsigned char *)"glXReleaseTexImageEXT");
 914
 915         compositor->correction_atom = XInternAtom(compositor->display, "GEOMETRY_CORRECTION", False);
 916         compositor->monitors_atom = XInternAtom(compositor->display, "GEOMETRY_CORRECTION_MONITORS", False);
 917
 918         compositor->nscreens = ScreenCount(compositor->display);
 919         compositor->screens = (CompositedScreen *)malloc(compositor->nscreens*sizeof(CompositedScreen));
 920         for(i=0; i<compositor->nscreens; ++i)
 921                 if(!initialize_screen(compositor, i))
 922                         return 0;
 923
 924         compositor->dirty = 1;
 925
 926         return 1;
 927 }
 928
 929 void shutdown_screen(Compositor *compositor, CompositedScreen *screen)
 930 {
 931         unsigned i;
 932
 933         use_gl(compositor, screen);
 934
 935         for(i=0; i<screen->nwindows; ++i)
 936         {
 937                 glDeleteTextures(1, &screen->windows[i].texture);
 938                 glDeleteTextures(1, &screen->windows[i].mask_texture);
 939                 if(screen->windows[i].pixmap)
 940                 {
 941                         glXDestroyPixmap(compositor->display, screen->windows[i].glx_pixmap);
 942                         XFreePixmap(compositor->display, screen->windows[i].pixmap);
 943                         XDamageDestroy(compositor->display, screen->windows[i].damage);
 944                 }
 945         }
 946
 947         for(i=0; i<screen->nmonitors; ++i)
 948         {
 949                 free(screen->monitors[i].name);
 950                 if(screen->monitors[i].enabled)
 951                 {
 952                         glDeleteBuffers(1, &screen->monitors[i].vertex_buffer);
 953                         glDeleteBuffers(1, &screen->monitors[i].index_buffer);
 954                         glDeleteVertexArrays(1, &screen->monitors[i].vertex_array);
 955                 }
 956         }
 957
 958         glDeleteBuffers(1, &screen->window_vertex_buffer);
 959         glDeleteVertexArrays(1, &screen->window_vertex_array);
 960         glDeleteFramebuffers(1, &screen->framebuffer);
 961         glDeleteTextures(1, &screen->fb_texture);
 962         glDeleteProgram(screen->program);
 963         glDeleteProgram(screen->masked_program);
 964         for(i=0; i<3; ++i)
 965                 glDeleteShader(screen->shaders[i]);
 966
 967         glXMakeContextCurrent(compositor->display, 0, 0, NULL);
 968         glXDestroyContext(compositor->display, screen->glx_context);
 969         glXDestroyWindow(compositor->display, screen->glx_window);
 970         XDestroyWindow(compositor->display, screen->render_window);
 971
 972         XCompositeReleaseOverlayWindow(compositor->display, screen->overlay);
 973
 974         free(screen->windows);
 975         free(screen->monitors);
 976 }
 977
 978 void shutdown_compositor(Compositor *compositor)
 979 {
 980         unsigned i;
 981
 982         for(i=0; i<compositor->nscreens; ++i)
 983                 shutdown_screen(compositor, &compositor->screens[i]);
 984         free(compositor->screens);
 985
 986         XCloseDisplay(compositor->display);
 987 }
 988
 989 void mark_dirty(Compositor *compositor, CompositedScreen *screen)
 990 {
 991         compositor->dirty = 1;
 992         screen->dirty = 1;
 993 }
 994
 995 void process_create_window_event(Compositor *compositor, XCreateWindowEvent *event)
 996 {
 997         CompositedScreen *screen;
 998
 999         if((screen = find_screen_by_root(compositor, event->parent)))
1000                 add_window(compositor, screen, event->window);
1001 }
1002
1003 void process_destroy_window_event(Compositor *compositor, XDestroyWindowEvent *event)
1004 {
1005         CompositedScreen *screen;
1006         CompositedWindow *window;
1007
1008         if((screen = find_screen_by_root(compositor, event->event)))
1009                 if((window = find_window(screen, event->window)))
1010                         remove_window(compositor, screen, window, 1);
1011 }
1012
1013 void process_map_event(Compositor *compositor, XMapEvent *event)
1014 {
1015         CompositedScreen *screen;
1016         CompositedWindow *window;
1017
1018         screen = find_screen_by_root(compositor, event->event);
1019         if(!screen)
1020                 return;
1021
1022         window = find_window(screen, event->window);
1023         if(!window)
1024                 return;
1025
1026         window->map_state = IsViewable;
1027         window->recreate_pixmap = 1;
1028         window->recreate_mask = 1;
1029
1030         mark_dirty(compositor, screen);
1031 }
1032
1033 void process_unmap_event(Compositor *compositor, XUnmapEvent *event)
1034 {
1035         CompositedScreen *screen;
1036         CompositedWindow *window;
1037
1038         screen = find_screen_by_root(compositor, event->event);
1039         if(!screen)
1040                 return;
1041
1042         window = find_window(screen, event->window);
1043         if(window)
1044                 window->map_state = IsUnviewable;
1045
1046         mark_dirty(compositor, screen);
1047 }
1048
1049 void process_reparent_event(Compositor *compositor, XReparentEvent *event)
1050 {
1051         CompositedScreen *screen;
1052         CompositedWindow *window;
1053
1054         screen = find_screen_by_root(compositor, event->event);
1055         if(!screen)
1056                 return;
1057
1058         if(event->parent==screen->root)
1059                 window = add_window(compositor, screen, event->window);
1060         else
1061         {
1062                 window = find_window(screen, event->window);
1063                 if(!window)
1064                         return;
1065
1066                 remove_window(compositor, screen, window, 0);
1067         }
1068
1069         if(window && window->map_state==IsViewable)
1070                 mark_dirty(compositor, screen);
1071 }
1072
1073 void process_configure_event(Compositor *compositor, XConfigureEvent *event)
1074 {
1075         CompositedScreen *screen;
1076         CompositedWindow *window;
1077
1078         screen = find_screen_by_root(compositor, event->event);
1079         if(!screen)
1080                 return;
1081
1082         window = find_window(screen, event->window);
1083         if(!window)
1084                 return;
1085
1086         window->x = event->x;
1087         window->y = event->y;
1088         if((unsigned)event->width!=window->width || (unsigned)event->height!=window->height || (unsigned)event->border_width!=window->border)
1089         {
1090                 window->width = event->width;
1091                 window->height = event->height;
1092                 window->border = event->border_width;
1093                 window->recreate_pixmap = 1;
1094         }
1095         reorder_window(screen, window, event->above);
1096
1097         if(window->map_state==IsViewable)
1098                 mark_dirty(compositor, screen);
1099 }
1100
1101 void process_property_event(Compositor *compositor, XPropertyEvent *event)
1102 {
1103         CompositedScreen *screen;
1104
1105         if(event->atom!=compositor->correction_atom)
1106                 return;
1107
1108         screen = find_screen_by_root(compositor, event->window);
1109         if(!screen)
1110                 return;
1111
1112         update_geometry_correction(compositor, screen);
1113 }
1114
1115 void process_damage_event(Compositor *compositor, XDamageNotifyEvent *event)
1116 {
1117         CompositedScreen *screen;
1118         CompositedWindow *window;
1119
1120         window = find_window_global(compositor, event->drawable, &screen);
1121         if(window && window->map_state==IsViewable)
1122                 mark_dirty(compositor, screen);
1123 }
1124
1125 void process_shape_event(Compositor *compositor, XShapeEvent *event)
1126 {
1127         CompositedScreen *screen;
1128         CompositedWindow *window;
1129
1130         if(event->kind!=ShapeBounding)
1131                 return;
1132
1133         window = find_window_global(compositor, event->window, &screen);
1134         if(window && window->map_state==IsViewable)
1135         {
1136                 window->recreate_mask = 1;
1137                 mark_dirty(compositor, screen);
1138         }
1139 }
1140
1141 void process_events(Compositor *compositor)
1142 {
1143         int pending;
1144         XEvent event;
1145
1146         pending = 0;
1147         while((pending || !compositor->dirty) && !terminate_requested)
1148         {
1149                 if(!pending)
1150                         pending = XPending(compositor->display);
1151
1152                 XNextEvent(compositor->display, &event);
1153                 if(pending)
1154                         --pending;
1155
1156                 switch(event.type)
1157                 {
1158                 case CreateNotify:
1159                         process_create_window_event(compositor, &event.xcreatewindow);
1160                         break;
1161                 case DestroyNotify:
1162                         process_destroy_window_event(compositor, &event.xdestroywindow);
1163                         break;
1164                 case MapNotify:
1165                         process_map_event(compositor, &event.xmap);
1166                         break;
1167                 case UnmapNotify:
1168                         process_unmap_event(compositor, &event.xunmap);
1169                         break;
1170                 case ReparentNotify:
1171                         process_reparent_event(compositor, &event.xreparent);
1172                         break;
1173                 case ConfigureNotify:
1174                         process_configure_event(compositor, &event.xconfigure);
1175                         break;
1176                 case PropertyNotify:
1177                         process_property_event(compositor, &event.xproperty);
1178                         break;
1179                 default:
1180                         if(event.type==compositor->damage_event+XDamageNotify)
1181                                 process_damage_event(compositor, (XDamageNotifyEvent *)&event);
1182                         else if(event.type==compositor->shape_event+ShapeNotify)
1183                                 process_shape_event(compositor, (XShapeEvent *)&event);
1184                         else
1185                                 printf("Event %d\n", event.type);
1186                 }
1187         }
1188 }
1189
1190 void refresh_screen(Compositor *compositor, CompositedScreen *screen)
1191 {
1192         unsigned i;
1193         int use_mask;
1194
1195         use_gl(compositor, screen);
1196
1197         glBindFramebuffer(GL_DRAW_FRAMEBUFFER, screen->framebuffer);
1198
1199         glClearColor(0.5f, 0.5f, 0.5f, 0.0f);
1200         glClear(GL_COLOR_BUFFER_BIT);
1201
1202         use_mask = -1;
1203         glBindVertexArray(screen->window_vertex_array);
1204         for(i=0; i<screen->nwindows; ++i)
1205         {
1206                 CompositedWindow *window;
1207
1208                 window = &screen->windows[i];
1209                 if(window->map_state!=IsViewable)
1210                         continue;
1211
1212                 if(window->use_mask!=use_mask)
1213                 {
1214                         use_mask = window->use_mask;
1215                         glUseProgram(use_mask ? screen->masked_program : screen->program);
1216                 }
1217
1218                 if(window->use_mask)
1219                 {
1220                         glActiveTexture(GL_TEXTURE1);
1221                         glBindTexture(GL_TEXTURE_2D, window->mask_texture);
1222                         glActiveTexture(GL_TEXTURE0);
1223                 }
1224
1225                 XDamageSubtract(compositor->display, window->damage, None, None);
1226
1227                 if(window->recreate_pixmap)
1228                         create_window_pixmap(compositor, screen, window);
1229                 if(window->recreate_mask)
1230                         update_window_mask(compositor, window);
1231
1232                 glBindTexture(GL_TEXTURE_2D, window->texture);
1233                 compositor->glXBindTexImageEXT(compositor->display, window->glx_pixmap, GLX_FRONT_LEFT_EXT, NULL);
1234                 glUniform4f((use_mask ? screen->masked_geometry_loc : screen->geometry_loc),
1235                         (float)window->x/screen->width, 1.0f-(float)(window->y+window->height)/screen->height,
1236                         (float)(window->width+2*window->border)/screen->width, (float)(window->height+2*window->border)/screen->height);
1237                 glDrawArrays(GL_TRIANGLE_STRIP, 0, 4);
1238                 compositor->glXReleaseTexImageEXT(compositor->display, window->glx_pixmap, GLX_FRONT_LEFT_EXT);
1239         }
1240
1241         glBindFramebuffer(GL_DRAW_FRAMEBUFFER, 0);
1242         glClearColor(0.5f, 0.0f, 0.5f, 0.0f);
1243         glClear(GL_COLOR_BUFFER_BIT);
1244         glBindTexture(GL_TEXTURE_2D, screen->fb_texture);
1245         glEnable(GL_PRIMITIVE_RESTART);
1246         glPrimitiveRestartIndex(0xFFFF);
1247         if(use_mask)
1248                 glUseProgram(screen->program);
1249
1250         for(i=0; i<screen->nmonitors; ++i)
1251         {
1252                 CompositedMonitor *monitor = &screen->monitors[i];
1253                 if(!monitor->enabled)
1254                         continue;
1255
1256                 glUniform4f(screen->geometry_loc,
1257                         (float)monitor->x/screen->width, 1.0f-(float)(monitor->y+monitor->height)/screen->height,
1258                         (float)monitor->width/screen->width, (float)monitor->height/screen->height);
1259
1260                 glBindVertexArray(monitor->vertex_array);
1261                 glDrawElements(GL_TRIANGLE_STRIP, monitor->nelements, GL_UNSIGNED_SHORT, NULL);
1262         }
1263
1264         glBindVertexArray(0);
1265
1266         glXSwapBuffers(compositor->display, screen->glx_window);
1267
1268         screen->dirty = 0;
1269 }
1270
1271 void refresh_all_screens(Compositor *compositor)
1272 {
1273         unsigned i;
1274
1275         for(i=0; i<compositor->nscreens; ++i)
1276         {
1277                 CompositedScreen *screen = &compositor->screens[i];
1278                 if(screen->dirty)
1279                         refresh_screen(compositor, screen);
1280         }
1281
1282         compositor->dirty = 0;
1283 }
1284
1285 void sighandler(int sig)
1286 {
1287         terminate_requested = 1;
1288         (void)sig;
1289 }
1290
1291 int main()
1292 {
1293         Compositor compositor;
1294
1295         signal(SIGINT, &sighandler);
1296         signal(SIGTERM, &sighandler);
1297
1298         if(!initialize_compositor(&compositor))
1299                 return 1;
1300
1301         while(!terminate_requested)
1302         {
1303                 process_events(&compositor);
1304                 if(compositor.dirty && !terminate_requested)
1305                         refresh_all_screens(&compositor);
1306         }
1307
1308         shutdown_compositor(&compositor);
1309
1310         return 0;
1311 }