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