src/libglw/glw.c

   1 #include <stdlib.h>
   2 #include <GL/glx.h>
   3 #include <X11/Xutil.h>
   4
   5 #include "glw.h"
   6
   7 /*--------------------------------------------------------------------*/
   8
   9 static Display      *dpy;
  10 static Window        win;
  11 static XVisualInfo  *xvi;
  12 static Atom          del;
  13 static XSizeHints   *siz;
  14 static GLXContext    ctx;
  15
  16 static int center_x = 0;
  17 static int center_y = 0;
  18
  19 static int last_x = 0;
  20 static int last_y = 0;
  21 static int height = 0;
  22
  23 /*--------------------------------------------------------------------*/
  24
  25 static int glx_init_dpy(void)
  26 {
  27     if ((dpy = XOpenDisplay(NULL)) == NULL)
  28         return 0;
  29
  30     if (glXQueryExtension(dpy, NULL, NULL) == False)
  31         return 0;
  32
  33     return 1;
  34 }
  35
  36 static int glx_init_xvi(int e)
  37 {
  38     int attributes[] = {
  39         GLX_STEREO,
  40         GLX_RGBA,
  41         GLX_DOUBLEBUFFER,
  42         GLX_DEPTH_SIZE, 16,
  43         None
  44     };
  45
  46     int *p = (e == 2) ? attributes : attributes + 1;
  47
  48     if ((xvi = glXChooseVisual(dpy, DefaultScreen(dpy), p)) == NULL)
  49         return 0;
  50
  51     if (xvi->class != TrueColor)
  52         return 0;
  53
  54     return 1;
  55 }
  56
  57
  58 static GLboolean glx_init_dec(void)
  59 {
  60     unsigned long hint[5] = { 2, 0, 0, 0, 0 };
  61     Atom prop;
  62
  63     if (!(prop = XInternAtom(dpy, "_MOTIF_WM_HINTS", True)))
  64         return GL_FALSE;
  65
  66     XChangeProperty(dpy, win, prop, prop, 32, PropModeReplace,
  67                     (unsigned char *) hint, 5);
  68
  69     return GL_TRUE;
  70 }
  71
  72 static int glx_init_win(int w, int h)
  73 {
  74     int W = w ? w : DisplayWidth (dpy, xvi->screen);
  75     int H = h ? h : DisplayHeight(dpy, xvi->screen);
  76
  77     Window root = RootWindow(dpy, xvi->screen);
  78     Visual *vis = xvi->visual;
  79     XSetWindowAttributes wa;
  80
  81     unsigned long valuemask = CWBorderPixel
  82                             | CWColormap
  83                             | CWEventMask;
  84
  85     wa.border_pixel = 0;
  86     wa.colormap     = XCreateColormap(dpy, root, vis, AllocNone);
  87     wa.event_mask   = StructureNotifyMask
  88                     | ExposureMask
  89                     | KeyPressMask
  90                     | KeyReleaseMask
  91                     | PointerMotionMask
  92                     | ButtonPressMask
  93                     | ButtonReleaseMask;
  94
  95     del = XInternAtom(dpy, "WM_DELETE_WINDOW", False);
  96     win = XCreateWindow(dpy, root, 0, 0, W, H, 0, xvi->depth,
  97                         InputOutput, vis, valuemask, &wa);
  98
  99     XSetWMProtocols(dpy, win, &del, 1);
 100
 101     return (w || h) ? 1 : glx_init_dec();
 102 }
 103
 104 static int glx_init_hnt(const char *s)
 105 {
 106     int w = DisplayWidth (dpy, DefaultScreen(dpy));
 107     int h = DisplayHeight(dpy, DefaultScreen(dpy));
 108
 109     siz = XAllocSizeHints();
 110
 111     if (siz)
 112     {
 113         siz->min_width  = 160;
 114         siz->min_height = 120;
 115         siz->max_width  = w;
 116         siz->max_height = h;
 117
 118         siz->flags = PMinSize | PMaxSize;
 119
 120         XmbSetWMProperties(dpy, win, s, s, NULL, 0, siz, NULL, NULL);
 121
 122         return 1;
 123     }
 124     return 0;
 125 }
 126
 127 static int glx_init_crs(void)
 128 {
 129     char   bit[] = { 0, 0, 0, 0, 0, 0, 0, 0 };
 130     Pixmap pix;
 131     Cursor crs;
 132     XColor rgb;
 133
 134     rgb.red   = 0;
 135     rgb.green = 0;
 136     rgb.blue  = 0;
 137
 138     pix = XCreateBitmapFromData(dpy, win, bit, 8, 8);
 139     crs = XCreatePixmapCursor(dpy, pix, pix, &rgb, &rgb, 0, 0);
 140
 141     XDefineCursor(dpy, win, crs);
 142     XFreePixmap(dpy, pix);
 143
 144     return 1;
 145 }
 146
 147 static int glx_init_ctx(void)
 148 {
 149     if ((ctx = glXCreateContext(dpy, xvi, NULL, True)) == NULL)
 150         return 0;
 151
 152     if (glXMakeCurrent(dpy, win, ctx) == True)
 153         return 1;
 154     else
 155         return 0;
 156 }
 157
 158 /*--------------------------------------------------------------------*/
 159
 160 static int glx_client(XClientMessageEvent *e)
 161 {
 162     if (e->data.l[0] == del)
 163         return GLW_CLOSE;
 164     else
 165         return 0;
 166 }
 167
 168 static int glx_render(XExposeEvent *e)
 169 {
 170     if (e->count == 0)
 171         return GLW_RENDER;
 172     else
 173         return 0;
 174 }
 175
 176 static int glx_resize(XConfigureEvent *e)
 177 {
 178     height = e->height;
 179     last_y = e->height;
 180     last_x = e->width;
 181
 182     center_x = e->width  / 2;
 183     center_y = e->height / 2;
 184
 185     return GLW_RESIZE;
 186 }
 187
 188 /*--------------------------------------------------------------------*/
 189
 190 static int glx_point(XMotionEvent *e)
 191 {
 192     last_x = e->x - center_x;
 193     last_y = e->y - center_y;
 194
 195     XWarpPointer(dpy, None, win, 0, 0, 0, 0, center_x, center_y);
 196
 197     return GLW_MOTION;
 198 }
 199
 200 static int glx_btn_d(XButtonEvent *e)
 201 {
 202     last_x = e->x;
 203     last_y = e->y;
 204
 205     switch (e->button)
 206     {
 207     case 1: return GLW_L_BTN_D;
 208     case 2: return GLW_M_BTN_D;
 209     case 3: return GLW_R_BTN_D;
 210     case 4: return GLW_WHEEL_D;
 211     case 5: return GLW_WHEEL_U;
 212     }
 213     return 0;
 214 }
 215
 216 static int glx_btn_u(XButtonEvent *e)
 217 {
 218     last_x = e->x;
 219     last_y = e->y;
 220
 221     switch (e->button)
 222     {
 223     case 1: return GLW_L_BTN_U;
 224     case 2: return GLW_M_BTN_U;
 225     case 3: return GLW_R_BTN_U;
 226     }
 227     return 0;
 228 }
 229
 230 /*--------------------------------------------------------------------*/
 231
 232 static int glx_key_d(XKeyEvent *e)
 233 {
 234     char c;
 235
 236     XLookupString(e, &c, 1, NULL, NULL);
 237     last_x = (int) c;
 238
 239     return GLW_KEY_D;
 240 }
 241
 242 static int glx_key_u(XKeyEvent *e)
 243 {
 244     char c;
 245
 246     XLookupString(e, &c, 1, NULL, NULL);
 247     last_x = (int) c;
 248
 249     return GLW_KEY_U;
 250 }
 251
 252 /*--------------------------------------------------------------------*/
 253
 254 int glw_create(const char *s, int w, int h, int e)
 255 {
 256     if (dpy == NULL)
 257     {
 258         if (!glx_init_dpy())     return 0;
 259         if (!glx_init_xvi(e))    return 0;
 260         if (!glx_init_win(w, h)) return 0;
 261         if (!glx_init_hnt(s))    return 0;
 262         if (!glx_init_crs())     return 0;
 263         if (!glx_init_ctx())     return 0;
 264
 265         XMapWindow(dpy, win);
 266     }
 267     return 1;
 268 }
 269
 270 void glw_delete(void)
 271 {
 272     if (dpy != NULL)
 273     {
 274         glXMakeCurrent(dpy, None, NULL);
 275         glXDestroyContext(dpy, ctx);
 276
 277         XDestroyWindow(dpy, win);
 278         XCloseDisplay(dpy);
 279
 280         dpy = NULL;
 281     }
 282 }
 283
 284 /*--------------------------------------------------------------------*/
 285
 286 int glw_update(int dirty, int wait)
 287 {
 288     XEvent e;
 289
 290     if (dirty) glXSwapBuffers(dpy, win);
 291
 292     if (wait || XPending(dpy) > 0)
 293     {
 294         XNextEvent(dpy, &e);
 295
 296         switch (e.type)
 297         {
 298         case ClientMessage:   return glx_client(&e.xclient);
 299         case Expose:          return glx_render(&e.xexpose);
 300         case ConfigureNotify: return glx_resize(&e.xconfigure);
 301
 302         case MotionNotify:    return glx_point(&e.xmotion);
 303         case ButtonPress:     return glx_btn_d(&e.xbutton);
 304         case ButtonRelease:   return glx_btn_u(&e.xbutton);
 305         case KeyPress:        return glx_key_d(&e.xkey);
 306         case KeyRelease:      return glx_key_u(&e.xkey);
 307         }
 308     }
 309     return 0;
 310 }
 311
 312 int glw_x(void)
 313 {
 314     return last_x;
 315 }
 316
 317 int glw_y(void)
 318 {
 319     return last_y;
 320 }
 321