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         Pixmap root_pixmap;
  75         GLXPixmap root_glx_pixmap;
  76         unsigned root_texture;
  77         CompositedWindow *windows;
  78         unsigned nwindows;
  79         unsigned windows_capacity;
  80         CompositedMonitor *monitors;
  81         unsigned nmonitors;
  82         int dirty;
  83 } CompositedScreen;
  84
  85 typedef struct Compositor
  86 {
  87         Display *display;
  88         CompositedScreen *screens;
  89         unsigned nscreens;
  90         int damage_event;
  91         int shape_event;
  92         PFNGLXCREATECONTEXTATTRIBSARBPROC glXCreateContextAttribsARB;
  93         PFNGLXBINDTEXIMAGEEXTPROC glXBindTexImageEXT;
  94         PFNGLXRELEASETEXIMAGEEXTPROC glXReleaseTexImageEXT;
  95         Atom root_pmap_atom;
  96         Atom correction_atom;
  97         Atom monitors_atom;
  98         int dirty;
  99 } Compositor;
 100
 101 static const char *vshader_src =
 102         "#version 150\n"
 103         "uniform vec4 geometry;\n"
 104         "in vec2 vertex;\n"
 105         "in vec2 texture_coord;\n"
 106         "out vec2 texcoord;\n"
 107         "void main()\n"
 108         "{\n"
 109         "  gl_Position = vec4((geometry.xy+vertex*geometry.zw)*2.0-1.0, 0.0, 1.0);\n"
 110         "  texcoord = texture_coord;\n"
 111         "}\n";
 112
 113 static const char *fshader_src =
 114         "#version 150\n"
 115         "uniform sampler2D image;\n"
 116         "in vec2 texcoord;\n"
 117         "out vec4 frag_color;\n"
 118         "void main()\n"
 119         "{\n"
 120         "  frag_color = texture(image, texcoord);\n"
 121         "}\n";
 122
 123 static const char *masked_fshader_src =
 124         "#version 150\n"
 125         "uniform sampler2D image;\n"
 126         "uniform sampler2D mask;\n"
 127         "in vec2 texcoord;\n"
 128         "out vec4 frag_color;\n"
 129         "void main()\n"
 130         "{\n"
 131         "  if(texture(mask, texcoord).r==0.0)\n"
 132         "    discard;\n"
 133         "  frag_color = texture(image, texcoord);\n"
 134         "}\n";
 135
 136 static const float window_vertices[] =
 137 {
 138         /* vertex    texcoord */
 139         0.0f, 1.0f,  0.0f, 0.0f,
 140         0.0f, 0.0f,  0.0f, 1.0f,
 141         1.0f, 1.0f,  1.0f, 0.0f,
 142         1.0f, 0.0f,  1.0f, 1.0f
 143 };
 144
 145 int terminate_requested = 0;
 146
 147 int x_error_handler(Display *display, XErrorEvent *event)
 148 {
 149         printf("Ignoring X error %d on resource %lx\n", event->error_code, event->resourceid);
 150         (void)display;
 151         return 0;
 152 }
 153
 154 int with_error(const char *message)
 155 {
 156         fprintf(stderr, "%s\n", message);
 157         return 0;
 158 }
 159
 160 int initialize_gl(Compositor *compositor, CompositedScreen *screen)
 161 {
 162         int attribs[9];
 163         unsigned i;
 164         GLXFBConfig *configs;
 165         int nconfigs;
 166         XVisualInfo *vi;
 167         XSetWindowAttributes win_attr;
 168
 169         i = 0;
 170         attribs[i++] = GLX_DRAWABLE_TYPE;
 171         attribs[i++] = GLX_WINDOW_BIT;
 172         attribs[i++] = GLX_RENDER_TYPE;
 173         attribs[i++] = GLX_RGBA_BIT;
 174         attribs[i++] = GLX_DOUBLEBUFFER;
 175         attribs[i++] = True;
 176         attribs[i++] = GLX_BIND_TO_TEXTURE_RGBA_EXT;
 177         attribs[i++] = True;
 178         attribs[i] = None;
 179
 180         configs = glXChooseFBConfig(compositor->display, screen->number, attribs, &nconfigs);
 181         if(!configs || !nconfigs)
 182                 return with_error("Could not find a suitable FBConfig");
 183         screen->fbconfig = configs[0];
 184         XFree(configs);
 185
 186         vi = glXGetVisualFromFBConfig(compositor->display, screen->fbconfig);
 187         win_attr.colormap = XCreateColormap(compositor->display, screen->root, vi->visual, AllocNone);
 188         screen->render_window = XCreateWindow(compositor->display, screen->overlay, 0, 0, screen->width, screen->height, 0, vi->depth, InputOutput, vi->visual, CWColormap, &win_attr);
 189         XMapWindow(compositor->display, screen->render_window);
 190
 191         screen->glx_window = glXCreateWindow(compositor->display, screen->fbconfig, screen->render_window, NULL);
 192
 193         i = 0;
 194         attribs[i++] = GLX_CONTEXT_FLAGS_ARB;
 195         attribs[i++] = GLX_CONTEXT_FORWARD_COMPATIBLE_BIT_ARB;
 196         attribs[i++] = GLX_CONTEXT_MAJOR_VERSION_ARB;
 197         attribs[i++] = 3;
 198         attribs[i++] = GLX_CONTEXT_MINOR_VERSION_ARB;
 199         attribs[i++] = 1;
 200         attribs[i] = None;
 201
 202         screen->glx_context = compositor->glXCreateContextAttribsARB(compositor->display, screen->fbconfig, NULL, True, attribs);
 203
 204         XFree(vi);
 205
 206         return 1;
 207 }
 208
 209 void use_gl(Compositor *compositor, CompositedScreen *screen)
 210 {
 211         glXMakeContextCurrent(compositor->display, screen->glx_window, screen->glx_window, screen->glx_context);
 212 }
 213
 214 unsigned compile_shader(GLenum type, const char *source)
 215 {
 216         unsigned shader;
 217         int status;
 218         char info_log[1024];
 219         GLsizei length;
 220
 221         shader = glCreateShader(type);
 222         glShaderSource(shader, 1, &source, NULL);
 223         glCompileShader(shader);
 224         glGetShaderiv(shader, GL_COMPILE_STATUS, &status);
 225         glGetShaderInfoLog(shader, sizeof(info_log), &length, info_log);
 226         if(!status)
 227         {
 228                 fprintf(stderr, "Shader compilation failed:\n%s\n", info_log);
 229                 glDeleteShader(shader);
 230                 return 0;
 231         }
 232         else if(length)
 233                 printf("Shader info log:\n%s\n", info_log);
 234
 235         return shader;
 236 }
 237
 238 unsigned link_program(unsigned vshader, unsigned fshader)
 239 {
 240         unsigned program;
 241         int status;
 242         char info_log[1024];
 243         GLsizei length;
 244
 245         program = glCreateProgram();
 246         glAttachShader(program, vshader);
 247         glAttachShader(program, fshader);
 248         glBindAttribLocation(program, 0, "vertex");
 249         glBindAttribLocation(program, 1, "texture_coord");
 250         glBindFragDataLocation(program, 0, "frag_color");
 251         glLinkProgram(program);
 252
 253         glGetProgramiv(program, GL_LINK_STATUS, &status);
 254         glGetProgramInfoLog(program, sizeof(info_log), &length, info_log);
 255         if(!status)
 256         {
 257                 fprintf(stderr, "Program link failed:\n%s\n", info_log);
 258                 glDeleteProgram(program);
 259                 return 0;
 260         }
 261         else if(length)
 262                 printf("Program info log:\n%s\n", info_log);
 263
 264         return program;
 265 }
 266
 267 unsigned create_2d_texture()
 268 {
 269         unsigned texture;
 270         glGenTextures(1, &texture);
 271         glBindTexture(GL_TEXTURE_2D, texture);
 272         glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR);
 273         glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_CLAMP_TO_EDGE);
 274         glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_CLAMP_TO_EDGE);
 275         return texture;
 276 }
 277
 278 int create_gl_resources(CompositedScreen *screen)
 279 {
 280         unsigned stride;
 281         int loc;
 282
 283         screen->shaders[0] = compile_shader(GL_VERTEX_SHADER, vshader_src);
 284         screen->shaders[1] = compile_shader(GL_FRAGMENT_SHADER, fshader_src);
 285         screen->shaders[2] = compile_shader(GL_FRAGMENT_SHADER, masked_fshader_src);
 286         if(!screen->shaders[0] || !screen->shaders[1] || !screen->shaders[2])
 287                 return 0;
 288
 289         screen->program = link_program(screen->shaders[0], screen->shaders[1]);
 290         if(!screen->program)
 291                 return 0;
 292
 293         screen->masked_program = link_program(screen->shaders[0], screen->shaders[2]);
 294         if(!screen->masked_program)
 295                 return 0;
 296
 297         screen->geometry_loc = glGetUniformLocation(screen->program, "geometry");
 298         screen->masked_geometry_loc = glGetUniformLocation(screen->masked_program, "geometry");
 299
 300         loc = glGetUniformLocation(screen->masked_program, "mask");
 301         if(loc>=0)
 302         {
 303                 glUseProgram(screen->masked_program);
 304                 glUniform1i(loc, 1);
 305         }
 306
 307         glGenBuffers(1, &screen->window_vertex_buffer);
 308         glBindBuffer(GL_ARRAY_BUFFER, screen->window_vertex_buffer);
 309         glBufferData(GL_ARRAY_BUFFER, sizeof(window_vertices), window_vertices, GL_STATIC_DRAW);
 310
 311         stride = 4*sizeof(float);
 312         glGenVertexArrays(1, &screen->window_vertex_array);
 313         glBindVertexArray(screen->window_vertex_array);
 314         glVertexAttribPointer(0, 2, GL_FLOAT, GL_FALSE, stride, NULL);
 315         glEnableVertexAttribArray(0);
 316         glVertexAttribPointer(1, 2, GL_FLOAT, GL_FALSE, stride, (void *)(2*sizeof(float)));
 317         glEnableVertexAttribArray(1);
 318         glBindVertexArray(0);
 319
 320         glBindBuffer(GL_ARRAY_BUFFER, 0);
 321
 322         screen->fb_texture = create_2d_texture();
 323         glTexImage2D(GL_TEXTURE_2D, 0, GL_RGB8, screen->width, screen->height, 0, GL_RGB, GL_UNSIGNED_BYTE, NULL);
 324         glBindTexture(GL_TEXTURE_2D, 0);
 325
 326         glGenFramebuffers(1, &screen->framebuffer);
 327         glBindFramebuffer(GL_DRAW_FRAMEBUFFER, screen->framebuffer);
 328         glFramebufferTexture2D(GL_DRAW_FRAMEBUFFER, GL_COLOR_ATTACHMENT0, GL_TEXTURE_2D, screen->fb_texture, 0);
 329         glDepthMask(GL_FALSE);
 330         glBindFramebuffer(GL_DRAW_FRAMEBUFFER, 0);
 331
 332         screen->root_texture = create_2d_texture();
 333
 334         return 1;
 335 }
 336
 337 CompositedWindow *find_window(CompositedScreen *screen, Window w)
 338 {
 339         unsigned i;
 340
 341         for(i=0; i<screen->nwindows; ++i)
 342                 if(screen->windows[i].window==w)
 343                         return &screen->windows[i];
 344
 345         return NULL;
 346 }
 347
 348 CompositedWindow *find_window_global(Compositor *compositor, Window w, CompositedScreen **screen)
 349 {
 350         unsigned i, j;
 351
 352         for(i=0; i<compositor->nscreens; ++i)
 353                 for(j=0; j<compositor->screens[i].nwindows; ++j)
 354                         if(compositor->screens[i].windows[j].window==w)
 355                         {
 356                                 if(screen)
 357                                         *screen = &compositor->screens[i];
 358                                 return &compositor->screens[i].windows[j];
 359                         }
 360
 361         if(screen)
 362                 *screen = NULL;
 363         return NULL;
 364 }
 365
 366 GLXPixmap pixmap_to_glx_pixmap(Compositor *compositor, CompositedScreen *screen, Pixmap pixmap)
 367 {
 368         int attribs[5];
 369         unsigned i;
 370
 371         i = 0;
 372         attribs[i++] = GLX_TEXTURE_TARGET_EXT;
 373         attribs[i++] = GLX_TEXTURE_2D_EXT;
 374         attribs[i++] = GLX_TEXTURE_FORMAT_EXT;
 375         attribs[i++] = GLX_TEXTURE_FORMAT_RGBA_EXT;
 376         attribs[i++] = None;
 377
 378         return glXCreatePixmap(compositor->display, screen->fbconfig, pixmap, attribs);
 379 }
 380
 381 void create_window_pixmap(Compositor *compositor, CompositedScreen *screen, CompositedWindow *window)
 382 {
 383         if(window->pixmap)
 384         {
 385                 glXDestroyPixmap(compositor->display, window->glx_pixmap);
 386                 XFreePixmap(compositor->display, window->pixmap);
 387         }
 388
 389         window->pixmap = XCompositeNameWindowPixmap(compositor->display, window->window);
 390         window->glx_pixmap = pixmap_to_glx_pixmap(compositor, screen, window->pixmap);
 391         window->recreate_pixmap = 0;
 392 }
 393
 394 void update_window_mask(Compositor *compositor, CompositedWindow *window)
 395 {
 396         Bool bounding_shaped;
 397         Bool clip_shaped;
 398         int xi, yi;
 399         XRectangle *rects;
 400         int rect_count;
 401         int rect_order;
 402         unsigned width;
 403         unsigned height;
 404         unsigned char *data;
 405         int i;
 406         unsigned y;
 407
 408         XShapeQueryExtents(compositor->display, window->window, &bounding_shaped, &xi, &yi, &width, &height, &clip_shaped, &xi, &yi, &width, &height);
 409         window->use_mask = bounding_shaped;
 410         if(!window->use_mask)
 411                 return;
 412
 413         rects = XShapeGetRectangles(compositor->display, window->window, ShapeBounding, &rect_count, &rect_order);
 414
 415         width = window->width+2*window->border;
 416         height = window->height+2*window->border;
 417         data = (unsigned char *)malloc(width*height);
 418         memset(data, 0, width*height);
 419         for(i=0; i<rect_count; ++i)
 420         {
 421                 rects[i].x += window->border;
 422                 rects[i].y += window->border;
 423                 if(rects[i].x>=(int)width || rects[i].y>=(int)height)
 424                         continue;
 425
 426                 if(rects[i].x<0)
 427                 {
 428                         if(-rects[i].x>rects[i].width)
 429                                 continue;
 430                         rects[i].width += rects[i].x;
 431                         rects[i].x = 0;
 432                 }
 433
 434                 if(rects[i].y<0)
 435                 {
 436                         if(-rects[i].y>rects[i].height)
 437                                 continue;
 438                         rects[i].height += rects[i].y;
 439                         rects[i].y = 0;
 440                 }
 441
 442                 if(rects[i].x+rects[i].width>(int)width)
 443                         rects[i].width = width-rects[i].x;
 444                 if(rects[i].y+rects[i].height>(int)height)
 445                         rects[i].height = height-rects[i].y;
 446
 447                 for(y=0; y<rects[i].height; ++y)
 448                 {
 449                         unsigned char *row = data+(rects[i].y+y)*width+rects[i].x;
 450                         memset(row, 255, rects[i].width);
 451                 }
 452         }
 453
 454         XFree(rects);
 455
 456         glBindTexture(GL_TEXTURE_2D, window->mask_texture);
 457         glPixelStorei(GL_UNPACK_ALIGNMENT, 1);
 458         glTexImage2D(GL_TEXTURE_2D, 0, GL_R8, width, height, 0, GL_RED, GL_UNSIGNED_BYTE, data);
 459
 460         free(data);
 461
 462         window->recreate_mask = 0;
 463 }
 464
 465 CompositedWindow *add_window(Compositor *compositor, CompositedScreen *screen, Window w)
 466 {
 467         CompositedWindow *window;
 468         XWindowAttributes win_attr;
 469
 470         if(w==screen->root || w==screen->overlay)
 471                 return NULL;
 472
 473         if(!XGetWindowAttributes(compositor->display, w, &win_attr))
 474         {
 475                 printf("XGetWindowAttributes failed; probably the window was already destroyed\n");
 476                 return NULL;
 477         }
 478         if(win_attr.class==InputOnly)
 479                 return NULL;
 480
 481         if(find_window(screen, w))
 482                 return NULL;
 483
 484         if(screen->nwindows==screen->windows_capacity)
 485         {
 486                 screen->windows = (CompositedWindow *)realloc(screen->windows, (screen->windows_capacity+1)*sizeof(CompositedWindow));
 487                 ++screen->windows_capacity;
 488         }
 489
 490         window = &screen->windows[screen->nwindows++];
 491
 492         window->window = w;
 493         window->x = win_attr.x;
 494         window->y = win_attr.y;
 495         window->width = win_attr.width;
 496         window->height = win_attr.height;
 497         window->border = win_attr.border_width;
 498         window->map_state = win_attr.map_state;
 499
 500         window->damage = XDamageCreate(compositor->display, window->window, XDamageReportNonEmpty);
 501         window->pixmap = None;
 502         window->glx_pixmap = None;
 503
 504         XCompositeRedirectWindow(compositor->display, window->window, CompositeRedirectManual);
 505         window->recreate_pixmap = (window->map_state==IsViewable);
 506
 507         window->texture = create_2d_texture();
 508         window->mask_texture = create_2d_texture();
 509         window->use_mask = 0;
 510         window->recreate_mask = (window->map_state==IsViewable);
 511
 512         XShapeSelectInput(compositor->display, window->window, ShapeNotifyMask);
 513
 514         return window;
 515 }
 516
 517 void remove_window(Compositor *compositor, CompositedScreen *screen, CompositedWindow *window, int destroyed)
 518 {
 519         unsigned i;
 520
 521         glDeleteTextures(1, &window->texture);
 522         if(!destroyed)
 523         {
 524                 XDamageDestroy(compositor->display, window->damage);
 525                 if(window->pixmap)
 526                 {
 527                         glXDestroyPixmap(compositor->display, window->glx_pixmap);
 528                         XFreePixmap(compositor->display, window->pixmap);
 529                 }
 530                 XCompositeUnredirectWindow(compositor->display, window->window, CompositeRedirectManual);
 531         }
 532
 533         --screen->nwindows;
 534         for(i=window-screen->windows; i<screen->nwindows; ++i)
 535                 screen->windows[i] = screen->windows[i+1];
 536 }
 537
 538 CompositedWindow *reorder_window(CompositedScreen *screen, CompositedWindow *window, Window above)
 539 {
 540         unsigned i, j;
 541         CompositedWindow hold;
 542
 543         i = window-screen->windows;
 544         if(above)
 545         {
 546                 for(j=0; j<screen->nwindows; ++j)
 547                         if(screen->windows[j].window==above)
 548                                 break;
 549
 550                 if(j>=screen->nwindows || i==j+1)
 551                         return window;
 552
 553                 if(j<i)
 554                         ++j;
 555         }
 556         else
 557                 j = 0;
 558
 559         hold = *window;
 560         if(i<j)
 561         {
 562                 for(; i<j; ++i)
 563                         screen->windows[i] = screen->windows[i+1];
 564         }
 565         else
 566         {
 567                 for(; i>j; --i)
 568                         screen->windows[i] = screen->windows[i-1];
 569         }
 570         screen->windows[j] = hold;
 571
 572         return &screen->windows[j];
 573 }
 574
 575 CompositedScreen *find_screen_by_root(Compositor *compositor, Window root)
 576 {
 577         unsigned i;
 578
 579         for(i=0; i<compositor->nscreens; ++i)
 580                 if(compositor->screens[i].root==root)
 581                         return &compositor->screens[i];
 582
 583         return NULL;
 584 }
 585
 586 void update_monitor_vertices(CompositedScreen *screen, CompositedMonitor *monitor)
 587 {
 588         unsigned t;
 589         unsigned data_size;
 590         float *vertex_data;
 591         unsigned short *index_data;
 592         unsigned x, y;
 593         unsigned i;
 594         float aspect;
 595         float cyl_radius;
 596         float cyl_arc;
 597         float sin_ksv;
 598         float cos_ksv;
 599         float distance;
 600         float eye[3];
 601         float look[3];
 602
 603         t = monitor->tessellation;
 604
 605         data_size = (t+1)*(t+1)*4*sizeof(float);
 606         vertex_data = (float *)malloc(data_size);
 607
 608         aspect = (float)monitor->width/monitor->height;
 609
 610         if(monitor->cylinder_depth)
 611         {
 612                 cyl_radius = (monitor->cylinder_depth*monitor->cylinder_depth+0.25f)/(2.0f*monitor->cylinder_depth);
 613                 cyl_arc = 2.0f*asin(0.5f/cyl_radius);
 614         }
 615
 616         sin_ksv = monitor->keystone_vertical/sqrt(1.0f+monitor->keystone_vertical*monitor->keystone_vertical);
 617         cos_ksv = sqrt(1.0f-sin_ksv*sin_ksv);
 618         distance = monitor->perspective+sin_ksv*((sin_ksv>0)-monitor->vertical_center)/aspect;
 619
 620         eye[0] = 0.0f;
 621         eye[1] = (monitor->vertical_center-0.5f)/aspect+sin_ksv*distance;
 622         eye[2] = cos_ksv*distance;
 623
 624         look[0] = 0.0f;
 625         look[1] = -sin_ksv;
 626         look[2] = -cos_ksv;
 627
 628         for(y=0; y<=t; ++y)
 629                 for(x=0; x<=t; ++x)
 630                 {
 631                         float *v;
 632
 633                         v = vertex_data+(y*(t+1)+x)*3;
 634                         v[0] = (float)x/t-0.5f;
 635                         v[1] = ((float)y/t-0.5f)/aspect;
 636                         v[2] = 0;
 637                         if(monitor->cylinder_depth)
 638                         {
 639                                 v[2] = (1.0f-cos(v[0]*cyl_arc))*cyl_radius-monitor->cylinder_depth;
 640                                 v[0] = sin(v[0]*cyl_arc)*cyl_radius;
 641                         }
 642                 }
 643
 644         for(y=t; y<=t; --y)
 645                 for(x=t; x<=t; --x)
 646                 {
 647                         float *v;
 648                         float px, py, pz;
 649                         float scale;
 650
 651                         v = vertex_data+(y*(t+1)+x)*3;
 652                         px = v[0]-eye[0];
 653                         py = (v[0]-eye[0])*look[0] - (v[1]-eye[1])*look[2] + (v[2]-eye[2])*look[1];
 654                         pz = (v[0]-eye[0])*look[0] + (v[1]-eye[1])*look[1] + (v[2]-eye[2])*look[2];
 655                         scale = monitor->perspective/pz;
 656
 657                         v = vertex_data+(y*(t+1)+x)*4;
 658                         v[0] = px*scale+0.5f;
 659                         v[1] = py*aspect*scale+monitor->vertical_center;
 660                         v[2] = (monitor->x+(float)x*monitor->width/t)/screen->width;
 661                         v[3] = 1.0f-(monitor->y+(1.0f-(float)y/t)*monitor->height)/screen->height;
 662                 }
 663
 664         glBindBuffer(GL_ARRAY_BUFFER, monitor->vertex_buffer);
 665         glBufferData(GL_ARRAY_BUFFER, data_size, vertex_data, GL_STATIC_DRAW);
 666         glBindBuffer(GL_ARRAY_BUFFER, 0);
 667         free(vertex_data);
 668
 669         monitor->nelements = t*((t+1)*2+1)-1;
 670         data_size = monitor->nelements*sizeof(unsigned short);
 671         index_data = (unsigned short *)malloc(data_size);
 672         i = 0;
 673         for(y=0; y<t; ++y)
 674         {
 675                 if(y>0)
 676                         index_data[i++] = 0xFFFF;
 677                 for(x=0; x<=t; ++x)
 678                 {
 679                         index_data[i++] = (y+1)*(t+1)+x;
 680                         index_data[i++] = y*(t+1)+x;
 681                 }
 682         }
 683         glBindBuffer(GL_ELEMENT_ARRAY_BUFFER, monitor->index_buffer);
 684         glBufferData(GL_ELEMENT_ARRAY_BUFFER, data_size, index_data, GL_STATIC_DRAW);
 685         glBindBuffer(GL_ELEMENT_ARRAY_BUFFER, 0);
 686         free(index_data);
 687 }
 688
 689 int initialize_monitor(Compositor *compositor, CompositedScreen *screen, XRRScreenResources *xrr_res, unsigned index)
 690 {
 691         CompositedMonitor *monitor;
 692         XRROutputInfo *output;
 693         int namelen;
 694         XRRCrtcInfo *crtc;
 695         unsigned buffers[2];
 696         unsigned stride;
 697
 698         monitor = &screen->monitors[index];
 699
 700         output = XRRGetOutputInfo(compositor->display, xrr_res, xrr_res->outputs[index]);
 701         namelen = strlen(output->name);
 702         monitor->name = (char *)malloc(namelen+1);
 703         strcpy(monitor->name, output->name);
 704         monitor->enabled = !!output->crtc;
 705         if(!monitor->enabled)
 706         {
 707                 XRRFreeOutputInfo(output);
 708                 return 1;
 709         }
 710
 711         crtc = XRRGetCrtcInfo(compositor->display, xrr_res, output->crtc);
 712         monitor->x = crtc->x;
 713         monitor->y = crtc->y;
 714         monitor->width = crtc->width;
 715         monitor->height = crtc->height;
 716         XRRFreeCrtcInfo(crtc);
 717         XRRFreeOutputInfo(output);
 718
 719         monitor->keystone_vertical = 0.0f;
 720         monitor->cylinder_depth = 0.0f;
 721         monitor->vertical_center = 0.5f;
 722         monitor->perspective = 1.0f;
 723
 724         glGenBuffers(2, buffers);
 725         monitor->vertex_buffer = buffers[0];
 726         monitor->index_buffer = buffers[1];
 727
 728         monitor->tessellation = 50;
 729         update_monitor_vertices(screen, monitor);
 730         stride = 4*sizeof(float);
 731
 732         glGenVertexArrays(1, &monitor->vertex_array);
 733         glBindVertexArray(monitor->vertex_array);
 734         glBindBuffer(GL_ARRAY_BUFFER, monitor->vertex_buffer);
 735         glVertexAttribPointer(0, 2, GL_FLOAT, GL_FALSE, stride, NULL);
 736         glEnableVertexAttribArray(0);
 737         glVertexAttribPointer(1, 2, GL_FLOAT, GL_FALSE, stride, (void *)(2*sizeof(float)));
 738         glEnableVertexAttribArray(1);
 739         glBindBuffer(GL_ARRAY_BUFFER, 0);
 740         glBindBuffer(GL_ELEMENT_ARRAY_BUFFER, monitor->index_buffer);
 741         glBindVertexArray(0);
 742
 743         return 1;
 744 }
 745
 746 CompositedMonitor *find_monitor_by_name(CompositedScreen *screen, char *name)
 747 {
 748         unsigned i;
 749
 750         for(i=0; i<screen->nmonitors; ++i)
 751                 if(!strcmp(screen->monitors[i].name, name))
 752                         return &screen->monitors[i];
 753
 754         return NULL;
 755 }
 756
 757 void update_geometry_correction(Compositor *compositor, CompositedScreen *screen)
 758 {
 759         Atom prop_type;
 760         int prop_format;
 761         unsigned long overflow;
 762         unsigned long names_length;
 763         char *names;
 764         unsigned long values_length;
 765         short *values;
 766         char *name_ptr;
 767         unsigned i;
 768
 769         XGetWindowProperty(compositor->display, screen->root, compositor->monitors_atom, 0, 64, False, XA_STRING,
 770                 &prop_type, &prop_format, &names_length, &overflow, (unsigned char **)&names);
 771         if(prop_type!=XA_STRING || prop_format!=8)
 772                 return;
 773
 774         XGetWindowProperty(compositor->display, screen->root, compositor->correction_atom, 0, 64, False, XA_INTEGER,
 775                 &prop_type, &prop_format, &values_length, &overflow, (unsigned char **)&values);
 776         if(prop_type!=XA_INTEGER || prop_format!=16)
 777         {
 778                 XFree(names);
 779                 return;
 780         }
 781
 782         use_gl(compositor, screen);
 783
 784         name_ptr = names;
 785         for(i=0; i*4<values_length; ++i)
 786         {
 787                 CompositedMonitor *monitor;
 788
 789                 if(name_ptr>=names+names_length)
 790                         break;
 791
 792                 monitor = find_monitor_by_name(screen, name_ptr);
 793                 if(monitor)
 794                 {
 795                         monitor->keystone_vertical = values[i*4]/10000.0f;
 796                         monitor->cylinder_depth = values[i*4+1]/10000.0f;
 797                         monitor->vertical_center = values[i*4+2]/10000.0f;
 798                         monitor->perspective = values[i*4+3]/10000.0f;
 799
 800                         if(monitor->enabled)
 801                                 update_monitor_vertices(screen, monitor);
 802                 }
 803
 804                 name_ptr += strlen(name_ptr)+1;
 805         }
 806
 807         XFree(names);
 808         XFree(values);
 809 }
 810
 811 void update_root_pixmap(Compositor *compositor, CompositedScreen *screen)
 812 {
 813         Atom prop_type;
 814         int prop_format;
 815         unsigned long overflow;
 816         unsigned long length;
 817         long *pixmap;
 818         Window root;
 819         int x, y;
 820         unsigned width;
 821         unsigned height;
 822         unsigned border;
 823         unsigned depth;
 824
 825         use_gl(compositor, screen);
 826
 827         if(screen->root_glx_pixmap)
 828         {
 829                 glXDestroyPixmap(compositor->display, screen->root_glx_pixmap);
 830                 screen->root_glx_pixmap = 0;
 831         }
 832
 833         XGetWindowProperty(compositor->display, screen->root, compositor->root_pmap_atom, 0, 1, False, XA_PIXMAP,
 834                 &prop_type, &prop_format, &length, &overflow, (unsigned char **)&pixmap);
 835         if(prop_type!=XA_PIXMAP || prop_format!=32)
 836         {
 837                 screen->root_pixmap = 0;
 838                 return;
 839         }
 840
 841         screen->root_pixmap = pixmap[0];
 842         if(XGetGeometry(compositor->display, screen->root_pixmap, &root, &x, &y, &width, &height, &border, &depth))
 843                 screen->root_glx_pixmap = pixmap_to_glx_pixmap(compositor, screen, screen->root_pixmap);
 844         else
 845                 screen->root_pixmap = None;
 846
 847         XFree(pixmap);
 848 }
 849
 850 int initialize_screen(Compositor *compositor, unsigned number)
 851 {
 852         CompositedScreen *screen;
 853         const char *extensions;
 854         Window dummy_root;
 855         int x, y;
 856         unsigned border;
 857         unsigned depth;
 858         XRRScreenResources *xrr_res;
 859         Window dummy_parent;
 860         Window *children;
 861         unsigned nchildren;
 862         unsigned i;
 863
 864         screen = &compositor->screens[number];
 865         screen->number = number;
 866
 867         extensions = glXQueryExtensionsString(compositor->display, screen->number);
 868         if(!strstr(extensions, "GLX_ARB_create_context"))
 869                 return with_error("GLX_ARB_create_context is required");
 870         if(!strstr(extensions, "GLX_EXT_texture_from_pixmap"))
 871                 return with_error("GLX_EXT_texture_from_pixmap is required");
 872
 873         screen->root = RootWindow(compositor->display, screen->number);
 874         XSelectInput(compositor->display, screen->root, SubstructureNotifyMask|PropertyChangeMask);
 875         screen->overlay = XCompositeGetOverlayWindow(compositor->display, screen->root);
 876         XGetGeometry(compositor->display, screen->overlay, &dummy_root, &x, &y, &screen->width, &screen->height, &border, &depth);
 877         XShapeCombineRectangles(compositor->display, screen->overlay, ShapeInput, 0, 0, NULL, 0, ShapeSet, Unsorted);
 878
 879         if(!initialize_gl(compositor, screen))
 880                 return 0;
 881
 882         use_gl(compositor, screen);
 883
 884         if(!create_gl_resources(screen))
 885                 return 0;
 886
 887         xrr_res = XRRGetScreenResources(compositor->display, screen->root);
 888         screen->nmonitors = xrr_res->noutput;
 889         screen->monitors = (CompositedMonitor *)malloc(screen->nmonitors*sizeof(CompositedMonitor));
 890         for(i=0; i<screen->nmonitors; ++i)
 891                 if(!initialize_monitor(compositor, screen, xrr_res, i))
 892                         return 0;
 893         XRRFreeScreenResources(xrr_res);
 894
 895         screen->root_pixmap = 0;
 896         screen->root_glx_pixmap = 0;
 897
 898         update_geometry_correction(compositor, screen);
 899         update_root_pixmap(compositor, screen);
 900
 901         XQueryTree(compositor->display, screen->root, &dummy_root, &dummy_parent, &children, &nchildren);
 902
 903         screen->windows = (CompositedWindow *)malloc(nchildren*sizeof(CompositedWindow));
 904         screen->nwindows = 0;
 905         screen->windows_capacity = nchildren;
 906
 907         for(i=0; i<nchildren; ++i)
 908                 add_window(compositor, screen, children[i]);
 909
 910         XFree(children);
 911
 912         screen->dirty = 1;
 913
 914         return 1;
 915 }
 916
 917 int initialize_compositor(Compositor *compositor)
 918 {
 919         int event_base;
 920         int error_base;
 921         int major_ver;
 922         int minor_ver;
 923         unsigned i;
 924
 925         compositor->display = XOpenDisplay(NULL);
 926         if(!compositor->display)
 927                 return with_error("Could not open X display");
 928
 929         XSetErrorHandler(&x_error_handler);
 930
 931         if(!XCompositeQueryExtension(compositor->display, &event_base, &error_base))
 932                 return with_error("XComposite is required but was not found");
 933         else if(!XCompositeQueryVersion(compositor->display, &major_ver, &minor_ver))
 934                 return with_error("Cannot determine XComposite version");
 935         else if(major_ver==0 && minor_ver<3)
 936                 return with_error("XComposite 0.3 or later is required");
 937
 938         if(!glXQueryExtension(compositor->display, &event_base, &error_base))
 939                 return with_error("GLX is required but was not found");
 940         else if(!glXQueryVersion(compositor->display, &major_ver, &minor_ver))
 941                 return with_error("Cannot determine GLX version");
 942         else if(major_ver<1 || (major_ver==1 && minor_ver<4))
 943                 return with_error("GLX 1.4 or later is required");
 944
 945         if(!XDamageQueryExtension(compositor->display, &compositor->damage_event, &error_base))
 946                 return with_error("XDamage is required but was not found");
 947         else if(!XDamageQueryVersion(compositor->display, &major_ver, &minor_ver))
 948                 return with_error("Cannot determine XDamage version");
 949         else if(major_ver<1)
 950                 return with_error("XDamage 1.0 or later is required");
 951
 952         if(!XShapeQueryExtension(compositor->display, &compositor->shape_event, &error_base))
 953                 return with_error("XShape is required but was not found");
 954         else if(!XShapeQueryVersion(compositor->display, &major_ver, &minor_ver))
 955                 return with_error("Cannot determine XShape version");
 956         else if(major_ver<1 || (major_ver==1 && minor_ver<1))
 957                 return with_error("XShape 1.1 or later is required");
 958
 959         if(!XRRQueryExtension(compositor->display, &event_base, &error_base))
 960                 return with_error("XRandR is required but was not found");
 961         else if(!XRRQueryVersion(compositor->display, &major_ver, &minor_ver))
 962                 return with_error("Cannot determine XRandR version");
 963         else if(major_ver<1 || (major_ver==1 && minor_ver<2))
 964                 return with_error("XRandR 1.2 or later is required");
 965
 966         compositor->glXCreateContextAttribsARB = (PFNGLXCREATECONTEXTATTRIBSARBPROC)glXGetProcAddress((unsigned char *)"glXCreateContextAttribsARB");
 967         compositor->glXBindTexImageEXT = (PFNGLXBINDTEXIMAGEEXTPROC)glXGetProcAddress((unsigned char *)"glXBindTexImageEXT");
 968         compositor->glXReleaseTexImageEXT = (PFNGLXRELEASETEXIMAGEEXTPROC)glXGetProcAddress((unsigned char *)"glXReleaseTexImageEXT");
 969
 970         compositor->root_pmap_atom = XInternAtom(compositor->display, "_XROOTPMAP_ID", False);
 971         compositor->correction_atom = XInternAtom(compositor->display, "GEOMETRY_CORRECTION", False);
 972         compositor->monitors_atom = XInternAtom(compositor->display, "GEOMETRY_CORRECTION_MONITORS", False);
 973
 974         compositor->nscreens = ScreenCount(compositor->display);
 975         compositor->screens = (CompositedScreen *)malloc(compositor->nscreens*sizeof(CompositedScreen));
 976         for(i=0; i<compositor->nscreens; ++i)
 977                 if(!initialize_screen(compositor, i))
 978                         return 0;
 979
 980         compositor->dirty = 1;
 981
 982         return 1;
 983 }
 984
 985 void shutdown_screen(Compositor *compositor, CompositedScreen *screen)
 986 {
 987         unsigned i;
 988
 989         use_gl(compositor, screen);
 990
 991         for(i=0; i<screen->nwindows; ++i)
 992         {
 993                 glDeleteTextures(1, &screen->windows[i].texture);
 994                 glDeleteTextures(1, &screen->windows[i].mask_texture);
 995                 if(screen->windows[i].pixmap)
 996                 {
 997                         glXDestroyPixmap(compositor->display, screen->windows[i].glx_pixmap);
 998                         XFreePixmap(compositor->display, screen->windows[i].pixmap);
 999                         XDamageDestroy(compositor->display, screen->windows[i].damage);
1000                 }
1001         }
1002
1003         for(i=0; i<screen->nmonitors; ++i)
1004         {
1005                 free(screen->monitors[i].name);
1006                 if(screen->monitors[i].enabled)
1007                 {
1008                         glDeleteBuffers(1, &screen->monitors[i].vertex_buffer);
1009                         glDeleteBuffers(1, &screen->monitors[i].index_buffer);
1010                         glDeleteVertexArrays(1, &screen->monitors[i].vertex_array);
1011                 }
1012         }
1013
1014         glDeleteTextures(1, &screen->root_texture);
1015         glXDestroyPixmap(compositor->display, screen->root_glx_pixmap);
1016
1017         glDeleteBuffers(1, &screen->window_vertex_buffer);
1018         glDeleteVertexArrays(1, &screen->window_vertex_array);
1019         glDeleteFramebuffers(1, &screen->framebuffer);
1020         glDeleteTextures(1, &screen->fb_texture);
1021         glDeleteProgram(screen->program);
1022         glDeleteProgram(screen->masked_program);
1023         for(i=0; i<3; ++i)
1024                 glDeleteShader(screen->shaders[i]);
1025
1026         glXMakeContextCurrent(compositor->display, 0, 0, NULL);
1027         glXDestroyContext(compositor->display, screen->glx_context);
1028         glXDestroyWindow(compositor->display, screen->glx_window);
1029         XDestroyWindow(compositor->display, screen->render_window);
1030
1031         XCompositeReleaseOverlayWindow(compositor->display, screen->overlay);
1032
1033         free(screen->windows);
1034         free(screen->monitors);
1035 }
1036
1037 void shutdown_compositor(Compositor *compositor)
1038 {
1039         unsigned i;
1040
1041         for(i=0; i<compositor->nscreens; ++i)
1042                 shutdown_screen(compositor, &compositor->screens[i]);
1043         free(compositor->screens);
1044
1045         XCloseDisplay(compositor->display);
1046 }
1047
1048 void mark_dirty(Compositor *compositor, CompositedScreen *screen)
1049 {
1050         compositor->dirty = 1;
1051         screen->dirty = 1;
1052 }
1053
1054 void process_create_window_event(Compositor *compositor, XCreateWindowEvent *event)
1055 {
1056         CompositedScreen *screen;
1057
1058         if((screen = find_screen_by_root(compositor, event->parent)))
1059                 add_window(compositor, screen, event->window);
1060 }
1061
1062 void process_destroy_window_event(Compositor *compositor, XDestroyWindowEvent *event)
1063 {
1064         CompositedScreen *screen;
1065         CompositedWindow *window;
1066
1067         if((screen = find_screen_by_root(compositor, event->event)))
1068                 if((window = find_window(screen, event->window)))
1069                 {
1070                         use_gl(compositor, screen);
1071                         remove_window(compositor, screen, window, 1);
1072                 }
1073 }
1074
1075 void process_map_event(Compositor *compositor, XMapEvent *event)
1076 {
1077         CompositedScreen *screen;
1078         CompositedWindow *window;
1079
1080         screen = find_screen_by_root(compositor, event->event);
1081         if(!screen)
1082                 return;
1083
1084         window = find_window(screen, event->window);
1085         if(!window)
1086                 return;
1087
1088         window->map_state = IsViewable;
1089         window->recreate_pixmap = 1;
1090         window->recreate_mask = 1;
1091
1092         mark_dirty(compositor, screen);
1093 }
1094
1095 void process_unmap_event(Compositor *compositor, XUnmapEvent *event)
1096 {
1097         CompositedScreen *screen;
1098         CompositedWindow *window;
1099
1100         screen = find_screen_by_root(compositor, event->event);
1101         if(!screen)
1102                 return;
1103
1104         window = find_window(screen, event->window);
1105         if(window)
1106                 window->map_state = IsUnviewable;
1107
1108         mark_dirty(compositor, screen);
1109 }
1110
1111 void process_reparent_event(Compositor *compositor, XReparentEvent *event)
1112 {
1113         CompositedScreen *screen;
1114         CompositedWindow *window;
1115
1116         screen = find_screen_by_root(compositor, event->event);
1117         if(!screen)
1118                 return;
1119
1120         if(event->parent==screen->root)
1121                 window = add_window(compositor, screen, event->window);
1122         else
1123         {
1124                 window = find_window(screen, event->window);
1125                 if(!window)
1126                         return;
1127
1128                 remove_window(compositor, screen, window, 0);
1129         }
1130
1131         if(window && window->map_state==IsViewable)
1132                 mark_dirty(compositor, screen);
1133 }
1134
1135 void process_configure_event(Compositor *compositor, XConfigureEvent *event)
1136 {
1137         CompositedScreen *screen;
1138         CompositedWindow *window;
1139
1140         screen = find_screen_by_root(compositor, event->event);
1141         if(!screen)
1142                 return;
1143
1144         window = find_window(screen, event->window);
1145         if(!window)
1146                 return;
1147
1148         window->x = event->x;
1149         window->y = event->y;
1150         if((unsigned)event->width!=window->width || (unsigned)event->height!=window->height || (unsigned)event->border_width!=window->border)
1151         {
1152                 window->width = event->width;
1153                 window->height = event->height;
1154                 window->border = event->border_width;
1155                 window->recreate_pixmap = 1;
1156         }
1157         reorder_window(screen, window, event->above);
1158
1159         if(window->map_state==IsViewable)
1160                 mark_dirty(compositor, screen);
1161 }
1162
1163 void process_property_event(Compositor *compositor, XPropertyEvent *event)
1164 {
1165         CompositedScreen *screen;
1166
1167         screen = find_screen_by_root(compositor, event->window);
1168         if(!screen)
1169                 return;
1170
1171         if(event->atom==compositor->correction_atom)
1172                 update_geometry_correction(compositor, screen);
1173         else if(event->atom==compositor->root_pmap_atom)
1174                 update_root_pixmap(compositor, screen);
1175 }
1176
1177 void process_damage_event(Compositor *compositor, XDamageNotifyEvent *event)
1178 {
1179         CompositedScreen *screen;
1180         CompositedWindow *window;
1181
1182         window = find_window_global(compositor, event->drawable, &screen);
1183         if(window && window->map_state==IsViewable)
1184                 mark_dirty(compositor, screen);
1185 }
1186
1187 void process_shape_event(Compositor *compositor, XShapeEvent *event)
1188 {
1189         CompositedScreen *screen;
1190         CompositedWindow *window;
1191
1192         if(event->kind!=ShapeBounding)
1193                 return;
1194
1195         window = find_window_global(compositor, event->window, &screen);
1196         if(window && window->map_state==IsViewable)
1197         {
1198                 window->recreate_mask = 1;
1199                 mark_dirty(compositor, screen);
1200         }
1201 }
1202
1203 void process_events(Compositor *compositor)
1204 {
1205         int pending;
1206         XEvent event;
1207
1208         pending = 0;
1209         while((pending || !compositor->dirty) && !terminate_requested)
1210         {
1211                 if(!pending)
1212                         pending = XPending(compositor->display);
1213
1214                 XNextEvent(compositor->display, &event);
1215                 if(pending)
1216                         --pending;
1217
1218                 switch(event.type)
1219                 {
1220                 case CreateNotify:
1221                         process_create_window_event(compositor, &event.xcreatewindow);
1222                         break;
1223                 case DestroyNotify:
1224                         process_destroy_window_event(compositor, &event.xdestroywindow);
1225                         break;
1226                 case MapNotify:
1227                         process_map_event(compositor, &event.xmap);
1228                         break;
1229                 case UnmapNotify:
1230                         process_unmap_event(compositor, &event.xunmap);
1231                         break;
1232                 case ReparentNotify:
1233                         process_reparent_event(compositor, &event.xreparent);
1234                         break;
1235                 case ConfigureNotify:
1236                         process_configure_event(compositor, &event.xconfigure);
1237                         break;
1238                 case PropertyNotify:
1239                         process_property_event(compositor, &event.xproperty);
1240                         break;
1241                 default:
1242                         if(event.type==compositor->damage_event+XDamageNotify)
1243                                 process_damage_event(compositor, (XDamageNotifyEvent *)&event);
1244                         else if(event.type==compositor->shape_event+ShapeNotify)
1245                                 process_shape_event(compositor, (XShapeEvent *)&event);
1246                         else
1247                                 printf("Event %d\n", event.type);
1248                 }
1249         }
1250 }
1251
1252 void refresh_screen(Compositor *compositor, CompositedScreen *screen)
1253 {
1254         unsigned i;
1255         int use_mask;
1256
1257         for(i=0; i<screen->nwindows; ++i)
1258                 if(screen->windows[i].map_state==IsViewable)
1259                         XDamageSubtract(compositor->display, screen->windows[i].damage, None, None);
1260         glXWaitX();
1261
1262         use_gl(compositor, screen);
1263
1264         glClearColor(0.0f, 0.0f, 0.0f, 0.0f);
1265         glBindFramebuffer(GL_DRAW_FRAMEBUFFER, screen->framebuffer);
1266
1267         use_mask = -1;
1268         glBindVertexArray(screen->window_vertex_array);
1269
1270         if(screen->root_pixmap)
1271         {
1272                 use_mask = 0;
1273                 glUseProgram(screen->program);
1274                 glBindTexture(GL_TEXTURE_2D, screen->root_texture);
1275                 compositor->glXBindTexImageEXT(compositor->display, screen->root_glx_pixmap, GLX_FRONT_LEFT_EXT, NULL);
1276                 glUniform4f(screen->geometry_loc, 0.0f, 0.0f, 1.0f, 1.0f);
1277                 glDrawArrays(GL_TRIANGLE_STRIP, 0, 4);
1278                 compositor->glXReleaseTexImageEXT(compositor->display, screen->root_glx_pixmap, GLX_FRONT_LEFT_EXT);
1279         }
1280         else
1281                 glClear(GL_COLOR_BUFFER_BIT);
1282
1283         for(i=0; i<screen->nwindows; ++i)
1284         {
1285                 CompositedWindow *window;
1286
1287                 window = &screen->windows[i];
1288                 if(window->map_state!=IsViewable)
1289                         continue;
1290
1291                 if(window->use_mask!=use_mask)
1292                 {
1293                         use_mask = window->use_mask;
1294                         glUseProgram(use_mask ? screen->masked_program : screen->program);
1295                 }
1296
1297                 if(window->use_mask)
1298                 {
1299                         glActiveTexture(GL_TEXTURE1);
1300                         glBindTexture(GL_TEXTURE_2D, window->mask_texture);
1301                         glActiveTexture(GL_TEXTURE0);
1302                 }
1303
1304                 if(window->recreate_pixmap)
1305                         create_window_pixmap(compositor, screen, window);
1306                 if(window->recreate_mask)
1307                         update_window_mask(compositor, window);
1308
1309                 glBindTexture(GL_TEXTURE_2D, window->texture);
1310                 compositor->glXBindTexImageEXT(compositor->display, window->glx_pixmap, GLX_FRONT_LEFT_EXT, NULL);
1311                 glUniform4f((use_mask ? screen->masked_geometry_loc : screen->geometry_loc),
1312                         (float)window->x/screen->width, 1.0f-(float)(window->y+window->height)/screen->height,
1313                         (float)(window->width+2*window->border)/screen->width, (float)(window->height+2*window->border)/screen->height);
1314                 glDrawArrays(GL_TRIANGLE_STRIP, 0, 4);
1315                 compositor->glXReleaseTexImageEXT(compositor->display, window->glx_pixmap, GLX_FRONT_LEFT_EXT);
1316         }
1317
1318         glBindFramebuffer(GL_DRAW_FRAMEBUFFER, 0);
1319         glClear(GL_COLOR_BUFFER_BIT);
1320         glBindTexture(GL_TEXTURE_2D, screen->fb_texture);
1321         glEnable(GL_PRIMITIVE_RESTART);
1322         glPrimitiveRestartIndex(0xFFFF);
1323         if(use_mask)
1324                 glUseProgram(screen->program);
1325
1326         for(i=0; i<screen->nmonitors; ++i)
1327         {
1328                 CompositedMonitor *monitor = &screen->monitors[i];
1329                 if(!monitor->enabled)
1330                         continue;
1331
1332                 glUniform4f(screen->geometry_loc,
1333                         (float)monitor->x/screen->width, 1.0f-(float)(monitor->y+monitor->height)/screen->height,
1334                         (float)monitor->width/screen->width, (float)monitor->height/screen->height);
1335
1336                 glBindVertexArray(monitor->vertex_array);
1337                 glDrawElements(GL_TRIANGLE_STRIP, monitor->nelements, GL_UNSIGNED_SHORT, NULL);
1338         }
1339
1340         glBindVertexArray(0);
1341
1342         glXSwapBuffers(compositor->display, screen->glx_window);
1343
1344         screen->dirty = 0;
1345 }
1346
1347 void refresh_all_screens(Compositor *compositor)
1348 {
1349         unsigned i;
1350
1351         for(i=0; i<compositor->nscreens; ++i)
1352         {
1353                 CompositedScreen *screen = &compositor->screens[i];
1354                 if(screen->dirty)
1355                         refresh_screen(compositor, screen);
1356         }
1357
1358         compositor->dirty = 0;
1359 }
1360
1361 void sighandler(int sig)
1362 {
1363         terminate_requested = 1;
1364         (void)sig;
1365 }
1366
1367 int main()
1368 {
1369         Compositor compositor;
1370
1371         signal(SIGINT, &sighandler);
1372         signal(SIGTERM, &sighandler);
1373
1374         if(!initialize_compositor(&compositor))
1375                 return 1;
1376
1377         while(!terminate_requested)
1378         {
1379                 process_events(&compositor);
1380                 if(compositor.dirty && !terminate_requested)
1381                         refresh_all_screens(&compositor);
1382         }
1383
1384         shutdown_compositor(&compositor);
1385
1386         return 0;
1387 }