hvirtual/guicast/bccapture.C

   1 #include "bccapture.h"
   2 #include "bcresources.h"
   3 #include "bcwindowbase.h"
   4 #include "colormodels.h"
   5 #include "vframe.h"
   6 #include <stdlib.h>
   7 #include <stdio.h>
   8 #include <X11/Xutil.h>
   9
  10 #include <libintl.h>
  11 #define _(String) gettext(String)
  12 #define gettext_noop(String) String
  13 #define N_(String) gettext_noop (String)
  14
  15
  16
  17
  18 // Byte orders:
  19 // 24 bpp packed:         bgr
  20 // 24 bpp unpacked:       0bgr
  21
  22
  23 BC_Capture::BC_Capture(int w, int h, char *display_path)
  24 {
  25         this->w = w;
  26         this->h = h;
  27
  28         data = 0;
  29         use_shm = 1;
  30         init_window(display_path);
  31         allocate_data();
  32 }
  33
  34
  35 BC_Capture::~BC_Capture()
  36 {
  37         delete_data();
  38         XCloseDisplay(display);
  39 }
  40
  41 int BC_Capture::init_window(char *display_path)
  42 {
  43         int bits_per_pixel;
  44         if(display_path && display_path[0] == 0) display_path = NULL;
  45         if((display = XOpenDisplay(display_path)) == NULL)
  46         {
  47                 printf(_("cannot connect to X server.\n"));
  48                 if(getenv("DISPLAY") == NULL)
  49                 printf(_("'DISPLAY' environment variable not set.\n"));
  50                 exit(-1);
  51                 return 1;
  52         }
  53
  54         screen = DefaultScreen(display);
  55         rootwin = RootWindow(display, screen);
  56         vis = DefaultVisual(display, screen);
  57         default_depth = DefaultDepth(display, screen);
  58         client_byte_order = (*(u_int32_t*)"a   ") & 0x00000001;
  59         server_byte_order = (XImageByteOrder(display) == MSBFirst) ? 0 : 1;
  60         char *data = 0;
  61         XImage *ximage;
  62         ximage = XCreateImage(display,
  63                                         vis,
  64                                         default_depth,
  65                                         ZPixmap,
  66                                         0,
  67                                         data,
  68                                         16,
  69                                         16,
  70                                         8,
  71                                         0);
  72         bits_per_pixel = ximage->bits_per_pixel;
  73         XDestroyImage(ximage);
  74         bitmap_color_model = BC_WindowBase::evaluate_color_model(client_byte_order, server_byte_order, bits_per_pixel);
  75
  76 // test shared memory
  77 // This doesn't ensure the X Server is on the local host
  78     if(use_shm && !XShmQueryExtension(display))
  79     {
  80         use_shm = 0;
  81     }
  82         return 0;
  83 }
  84
  85
  86 int BC_Capture::allocate_data()
  87 {
  88 // try shared memory
  89         if(!display) return 1;
  90     if(use_shm)
  91         {
  92             ximage = XShmCreateImage(display, vis, default_depth, ZPixmap, (char*)NULL, &shm_info, w, h);
  93
  94                 shm_info.shmid = shmget(IPC_PRIVATE, h * ximage->bytes_per_line, IPC_CREAT | 0777);
  95                 if(shm_info.shmid < 0) perror("BC_Capture::allocate_data shmget");
  96                 data = (unsigned char *)shmat(shm_info.shmid, NULL, 0);
  97                 shmctl(shm_info.shmid, IPC_RMID, 0);
  98                 ximage->data = shm_info.shmaddr = (char*)data;  // setting ximage->data stops BadValue
  99                 shm_info.readOnly = 0;
 100
 101 // Crashes here if remote server.
 102                 BC_Resources::error = 0;
 103                 XShmAttach(display, &shm_info);
 104         XSync(display, False);
 105                 if(BC_Resources::error)
 106                 {
 107                         XDestroyImage(ximage);
 108                         shmdt(shm_info.shmaddr);
 109                         use_shm = 0;
 110                 }
 111         }
 112
 113         if(!use_shm)
 114         {
 115 // need to use bytes_per_line for some X servers
 116                 data = 0;
 117                 ximage = XCreateImage(display, vis, default_depth, ZPixmap, 0, (char*)data, w, h, 8, 0);
 118                 data = (unsigned char*)malloc(h * ximage->bytes_per_line);
 119                 XDestroyImage(ximage);
 120
 121                 ximage = XCreateImage(display, vis, default_depth, ZPixmap, 0, (char*)data, w, h, 8, 0);
 122         }
 123
 124         row_data = new unsigned char*[h];
 125         for(int i = 0; i < h; i++)
 126         {
 127                 row_data[i] = &data[i * ximage->bytes_per_line];
 128         }
 129 // This differs from the depth parameter of the top_level.
 130         bits_per_pixel = ximage->bits_per_pixel;
 131         return 0;
 132 }
 133
 134 int BC_Capture::delete_data()
 135 {
 136         if(!display) return 1;
 137         if(data)
 138         {
 139                 if(use_shm)
 140                 {
 141                         XShmDetach(display, &shm_info);
 142                         XDestroyImage(ximage);
 143                         shmdt(shm_info.shmaddr);
 144                 }
 145                 else
 146                 {
 147                         XDestroyImage(ximage);
 148                 }
 149
 150 // data is automatically freed by XDestroyImage
 151                 data = 0;
 152                 delete row_data;
 153         }
 154         return 0;
 155 }
 156
 157
 158 int BC_Capture::get_w() { return w; }
 159 int BC_Capture::get_h() { return h; }
 160
 161 // Capture a frame from the screen
 162 #define CAPTURE_FRAME_HEAD \
 163         for(int i = 0; i < h; i++) \
 164         { \
 165                 unsigned char *input_row = row_data[i]; \
 166                 unsigned char *output_row = (unsigned char*)frame->get_rows()[i]; \
 167                 for(int j = 0; j < w; j++) \
 168                 {
 169
 170 #define CAPTURE_FRAME_TAIL \
 171                 } \
 172         }
 173
 174
 175
 176 int BC_Capture::capture_frame(VFrame *frame, int &x1, int &y1)
 177 {
 178         if(!display) return 1;
 179         if(x1 < 0) x1 = 0;
 180         if(y1 < 0) y1 = 0;
 181         if(x1 > get_top_w() - w) x1 = get_top_w() - w;
 182         if(y1 > get_top_h() - h) y1 = get_top_h() - h;
 183
 184
 185 // Read the raw data
 186         if(use_shm)
 187                 XShmGetImage(display, rootwin, ximage, x1, y1, 0xffffffff);
 188         else
 189                 XGetSubImage(display, rootwin, x1, y1, w, h, 0xffffffff, ZPixmap, ximage, 0, 0);
 190
 191         cmodel_transfer(frame->get_rows(),
 192                 row_data,
 193                 frame->get_y(),
 194                 frame->get_u(),
 195                 frame->get_v(),
 196                 0,
 197                 0,
 198                 0,
 199                 0,
 200                 0,
 201                 w,
 202                 h,
 203                 0,
 204                 0,
 205                 frame->get_w(),
 206                 frame->get_h(),
 207                 bitmap_color_model,
 208                 frame->get_color_model(),
 209                 0,
 210                 frame->get_w(),
 211                 w);
 212
 213         return 0;
 214 }
 215
 216 int BC_Capture::get_top_w()
 217 {
 218         Screen *screen_ptr = XDefaultScreenOfDisplay(display);
 219         return WidthOfScreen(screen_ptr);
 220 }
 221
 222 int BC_Capture::get_top_h()
 223 {
 224         Screen *screen_ptr = XDefaultScreenOfDisplay(display);
 225         return HeightOfScreen(screen_ptr);
 226 }