diff options
Diffstat (limited to 'src')
| -rw-r--r-- | src/xbouncing.c | 101 |
1 files changed, 91 insertions, 10 deletions
diff --git a/src/xbouncing.c b/src/xbouncing.c index 7ab5d89..d073c67 100644 --- a/src/xbouncing.c +++ b/src/xbouncing.c @@ -1,3 +1,4 @@ +#include <stdio.h> #include <stdlib.h> #include <stdbool.h> #include <string.h> @@ -81,7 +82,10 @@ int main (const int argc, const char **argv) { state.p2.x = state.w = dvdlogo_width; state.p2.y = state.h = dvdlogo_height; - init_x11(); + if (!init_x11()) { + ec = 1; + goto END; + } // - load xbm // - init X11 @@ -112,11 +116,32 @@ static void update_screen_info (void) { x11.refresh_interval.tv_nsec = 1000000000 / x11.refresh_rate; } +static void print_l18n_xopen_err (void) { + const char *LANG = getenv("LANG"); + const char *msg; + + if (strncmp(LANG, "ko", 2) == 0) { + msg = "X 서버 연결 실패. `ssh -X` 옵션으로 X11 포워딩을 활성화 하셨습니까?"; + } + else { + msg = + "Could not open X display. " + "Did you enable X11 forwarding with `ssh -X` option?"; + } + + fprintf(stderr, "%s\n", msg); +} + static bool init_x11 (void) { XSizeHints hints = { 0, }; XGCValues gcv = { 0, }; x11.dpy = XOpenDisplay(NULL); + if (x11.dpy == NULL) { + print_l18n_xopen_err(); + return false; + } + // after this point, X11 will call exit() upon error. x11.scr_num = DefaultScreen(x11.dpy); // TODO: parameterise x11.scr = XScreenOfDisplay(x11.dpy, x11.scr_num); x11.rwnd = RootWindowOfScreen(x11.scr); @@ -334,13 +359,13 @@ static int get_geo_nullable ( #undef CHK_ASS } -static void do_move (bool *redraw) { +static void do_move (bool *redraw, const double v_factor) { double dx, dy; const unsigned int root_w = XWidthOfScreen(x11.scr); const unsigned int root_h = XHeightOfScreen(x11.scr); - dx = state.dir.x * param.vel / x11.refresh_rate; - dy = state.dir.y * param.vel / x11.refresh_rate; + dx = state.dir.x * param.vel / x11.refresh_rate * v_factor; + dy = state.dir.y * param.vel / x11.refresh_rate * v_factor; state.p1.x += dx; state.p1.y += dy; state.p2.x += dx; @@ -381,10 +406,46 @@ static void do_move (bool *redraw) { } } +static void sub_ts ( + struct timespec *out, + const struct timespec *a, + const struct timespec *b) +{ + if (a->tv_nsec < b->tv_nsec) { + out->tv_sec = a->tv_sec - 1 - b->tv_sec; + out->tv_nsec = 1000000000 + a->tv_nsec - b->tv_nsec; + } + else { + out->tv_sec = a->tv_sec - b->tv_sec; + out->tv_nsec = a->tv_nsec - b->tv_nsec; + } +} + +static int cmp_ts (const struct timespec *a, const struct timespec *b) { + if (a->tv_sec < b->tv_sec) { + return -1; + } + else if (a->tv_sec > b->tv_sec) { + return 1; + } + + return a->tv_nsec < b->tv_nsec ? -1 : a->tv_nsec > b->tv_nsec ? 1 : 0; +} + +static double ts2d (const struct timespec *x) { + return (double)x->tv_nsec / 1000000000 + x->tv_sec; +} + static int main_loop (void) { bool loop_flag = true; bool redraw; + struct timespec ts_now; + struct timespec ts_last_tick; + struct timespec ts_delta; + double v_factor = 1.0; + clock_gettime(CLOCK_MONOTONIC, &ts_now); + memcpy(&ts_last_tick, &ts_now, sizeof(struct timespec)); while (true) { redraw = false; @@ -394,19 +455,39 @@ static int main_loop (void) { break; } - do_move(&redraw); + if (false) { + fprintf(stderr, "v_factor: %.6lf\n", v_factor); + } + + do_move(&redraw, v_factor); if (redraw) { draw(); } - if (true) { - XSync(x11.dpy, False); + if (false) { + // manually introduce network delay for testing + ts_delta.tv_sec = 0; + ts_delta.tv_nsec = 50000000; // 50ms + nanosleep(&ts_delta, NULL); } - else { - XFlush(x11.dpy); + + clock_gettime(CLOCK_MONOTONIC, &ts_now); + sub_ts(&ts_delta, &ts_now, &ts_last_tick); + + // TODO: to alleviate stuttering, + // do PID control to keep the X11 command queue under certain limit + + v_factor = 1.0 + ts2d(&ts_delta) / ts2d(&x11.refresh_interval); + + if (cmp_ts(&ts_delta, &x11.refresh_interval) < 0) { + struct timespec ts_sleep; + + sub_ts(&ts_sleep, &x11.refresh_interval, &ts_delta); + nanosleep(&ts_sleep, NULL); } - nanosleep(&x11.refresh_interval, NULL); + + clock_gettime(CLOCK_MONOTONIC, &ts_last_tick); } return 0; |