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