From 8b9c97a2e36ee554135526202fdb128ecde4c068 Mon Sep 17 00:00:00 2001 From: girst Date: Thu, 17 May 2018 23:41:04 +0200 Subject: [PATCH] initial (proof-of-concept-y) code --- LICENSE | 619 ++++++++++++++++++++++++++++++++++++++++++++++++++++++ Makefile | 8 + README.md | 57 +++++ viiper.c | 512 ++++++++++++++++++++++++++++++++++++++++++++ 4 files changed, 1196 insertions(+) create mode 100644 LICENSE create mode 100644 Makefile create mode 100644 README.md create mode 100644 viiper.c diff --git a/LICENSE b/LICENSE new file mode 100644 index 0000000..bc08fe2 --- /dev/null +++ b/LICENSE @@ -0,0 +1,619 @@ + GNU GENERAL PUBLIC LICENSE + Version 3, 29 June 2007 + + Copyright (C) 2007 Free Software Foundation, Inc. + Everyone is permitted to copy and distribute verbatim copies + of this license document, but changing it is not allowed. + + Preamble + + The GNU General Public License is a free, copyleft license for +software and other kinds of works. + + The licenses for most software and other practical works are designed +to take away your freedom to share and change the works. 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Limitation of Liability. + + IN NO EVENT UNLESS REQUIRED BY APPLICABLE LAW OR AGREED TO IN WRITING +WILL ANY COPYRIGHT HOLDER, OR ANY OTHER PARTY WHO MODIFIES AND/OR CONVEYS +THE PROGRAM AS PERMITTED ABOVE, BE LIABLE TO YOU FOR DAMAGES, INCLUDING ANY +GENERAL, SPECIAL, INCIDENTAL OR CONSEQUENTIAL DAMAGES ARISING OUT OF THE +USE OR INABILITY TO USE THE PROGRAM (INCLUDING BUT NOT LIMITED TO LOSS OF +DATA OR DATA BEING RENDERED INACCURATE OR LOSSES SUSTAINED BY YOU OR THIRD +PARTIES OR A FAILURE OF THE PROGRAM TO OPERATE WITH ANY OTHER PROGRAMS), +EVEN IF SUCH HOLDER OR OTHER PARTY HAS BEEN ADVISED OF THE POSSIBILITY OF +SUCH DAMAGES. + + 17. Interpretation of Sections 15 and 16. + + If the disclaimer of warranty and limitation of liability provided +above cannot be given local legal effect according to their terms, +reviewing courts shall apply local law that most closely approximates +an absolute waiver of all civil liability in connection with the +Program, unless a warranty or assumption of liability accompanies a +copy of the Program in return for a fee. diff --git a/Makefile b/Makefile new file mode 100644 index 0000000..14c2a58 --- /dev/null +++ b/Makefile @@ -0,0 +1,8 @@ +.PHONY: all clean +all: viiper + +viiper: viiper.c + gcc viiper.c -o viiper -g + +clean: + rm -f viiper diff --git a/README.md b/README.md new file mode 100644 index 0000000..9745007 --- /dev/null +++ b/README.md @@ -0,0 +1,57 @@ +# VIIper - a Snake Clone for Unicode-compatible Terminals + +## Dependencies + + - A VTE based terminal (like GNOME Terminal and a whole bunch of others) + - Google Noto's Color Emoji Font (Fedora: `google-noto-emoji-color-fonts.noarch`) + +## Keybindings + +hjkl or cursor keys move the snake. +r to restart, p to pause, q to quit. + +## TODO + + - DONE base game: fixed field size, fixed speed + - food (unicode) + - put 'sprites' into `schemes.h` + - snake elongates + - unicode chars + - timer, score, increasing speed + - special items: slower snake, shorter snake, etc. + - input buffer (so fast 180° turns get executed) + +## Notes + +### terminal compat + +to display emojis, we need a terminal that can handle a color emoji font (no +shit, sherlock). mlterm, xterm and urxvt didn't work in my tests (mlterm might +work if compiled correctly, the other two use bitmap fonts and i don't think +there are any w/ emoji support). konsole will have to be tested in the future. +i intend to put bonus items in the game that will only be visible for a short +time. when they get near the end of their life, SGI-5 (blink) will make them +blink. this is supported in gnome-term 3.28 (vte 0.52) which is supplied with +fedora 28. [bug report](https://bugzilla.gnome.org/show_bug.cgi?id=579964) + +### drawing the snake + +to draw the snake with box chars, we need to know which glyph to draw. + +our current position is X, and our predecessor and successor are on one of +`[NESW]` of us (we need to compute the relpos from the absolute). we need to +draw a line between them. note that head and tail have `NULL` as pre-/successor. + +``` + [N] +[W][X][E] + [S] +``` + +6 combinations (+ reverse): + - N-S -> `||` + - W-E -> `==` + - N-E -> `'=` + - E-S -> `,=` + - S-W -> `=,` + - W-N -> `='` diff --git a/viiper.c b/viiper.c new file mode 100644 index 0000000..53abcb9 --- /dev/null +++ b/viiper.c @@ -0,0 +1,512 @@ +/******************************************************************************* + viiper 0.1 + By Tobias Girstmair, 2018 + + ./viiper 40x25 + (see ./viiper -h for full list of options) + + KEYBINDINGS: - hjkl to move + - p to pause and resume + - r to restart + - q to quit + - (see `./minesviiper -h' for all keybindings) + + GNU GPL v3, see LICENSE or https://www.gnu.org/licenses/gpl-3.0.txt +*******************************************************************************/ + + +#define _POSIX_C_SOURCE 2 /*for getopt, sigaction in c99*/ +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include + +#define MIN(a,b) (a>b?b:a) +#define MAX(a,b) (a>b?a:b) +#define CLAMP(a,m,M) (aM?M:a)) +#define printm(n, s) for (int _loop = 0; _loop < n; _loop++) fputs (s, stdout) +#define print(str) fputs (str?str:"", stdout) +#define CTRL_ 0x1F & + +#define COL_OFFSET 1 +#define LINE_OFFSET 1 +#define LINES_AFTER 1 +#define CW 2 /* cell width */ +#define SHORTHELP "%s [OPTIONS] [FIELDSIZE]\n" +#define LONGHELP \ + "OPTIONS:\n" \ + " -h(elp)\n" \ + "FIELDSIZE:\n" \ + " WxH (width 'x' height)\n" \ + " defaults to 30x20\n" \ + "\n" \ + "Keybindings:\n" \ + " hjkl: move left/down/up/right\n" \ + " p: pause / unpause\n" \ + " r: start a new game\n" \ + " q: quit\n" + +struct snake { + int r; /* row */ + int c; /* column */ + struct snake* next; /* points to tail */ +}; +struct item { //TODO: make it more abstract (type should encode glyph, points, etc) + int r; /* row */ + int c; /* column */ + int t; /* type */ + int s; /* spawn time (for bonus) */ + char* g; /* glyph */ + struct item* prev; + struct item* next; +}; +enum direction { + NONE, + EAST, + NORTH, + SOUTH, + WEST, +}; +enum item_type { + NO_ITEM, + FOOD, + BONUS, +}; +struct game { + int w; /* field width */ + int h; /* field height */ + struct snake* s; /* snek */ + struct item* i; /* items (food, boni) */ + int d; /* direction the snake is looking */ + int n;/* direction to move on next tick */ + int t; /* time of game start */ + int p; /* score */ +} g; + +struct opt { + void* scheme; //TODO + int l; /* initial snake length */ + int s; //TODO: initial snake speed +} op; + +int viiper(void); +void snake_advance (void); +void spawn_item (int type); +void consume_item (struct item* i); +void show_playfield (void); +void snake_append (struct snake* s, int row, int col); +void init_snake(); +void quit (void); +int getctrlseq (void); +void move_ph (int line, int col); +void clamp_fieldsize (void); +void timer_setup (int enable); +void signal_setup (void); +void signal_handler (int signum); +void screen_setup (int enable); +void raw_mode(int enable); +enum event { + /* for getctrlseq() */ + CTRSEQ_NULL = 0, + CTRSEQ_EOF = -1, + CTRSEQ_INVALID = -2, + CTRSEQ_MOUSE = -3, + CTRSEQ_CURSOR_LEFT = -7, + CTRSEQ_CURSOR_DOWN = -8, + CTRSEQ_CURSOR_UP = -9, + CTRSEQ_CURSOR_RIGHT = -10, +}; + +int main (int argc, char** argv) { + /* defaults: */ + g.w = 30; //two-char-width + g.h = 20; + op.l = 10; + op.scheme = NULL; + + int optget; + opterr = 0; /* don't print message on unrecognized option */ + while ((optget = getopt (argc, argv, "+h")) != -1) { + switch (optget) { + case 'h': + default: + fprintf (stderr, SHORTHELP LONGHELP, argv[0]); + return !(optget=='h'); + } + } if (optind < argc) { /* parse Fieldspec */ + } + + srand(time(0)); + signal_setup(); + screen_setup(1); + atexit (*quit); + + //TODO: call viiper() in a game loop + viiper(); +quit: + return 0; +} + +int viiper(void) { + init_snake(); + show_playfield (); + g.d = g.n = EAST; + + timer_setup(1); + + spawn_item(FOOD); + + for(;;) { + switch (getctrlseq()) { + case 'h': if (g.d != EAST) g.n = WEST; break; + case 'j': if (g.d != NORTH) g.n = SOUTH; break; + case 'k': if (g.d != SOUTH) g.n = NORTH; break; + case 'l': if (g.d != WEST) g.n = EAST; break; + case 'r': /*TODO:restart*/ return 0; + case 'q': return 0; + case CTRL_'L': + screen_setup(1); + show_playfield(); + break; + } + + print ("\033[H\033[J"); + show_playfield ();//TODO: only redraw diff + } + +} + +void snake_advance (void) { + g.d = g.n; + int new_row = g.s->r +(g.d==SOUTH) -(g.d==NORTH); + int new_col = g.s->c +(g.d==EAST) -(g.d==WEST); + + //TODO: detect food hit and spawn a new food. + for (struct item* i = g.i; i; i = i->next) { + if (i->r == new_row && i->c == new_col) { + consume_item (i); + spawn_item(FOOD); + } + } + + if (new_row >= g.h || new_col >= g.w || new_row < 0 || new_col < 0) + exit(1); //TODO: longjump? + + struct snake* new_head; + struct snake* new_tail; /* former second-to-last element */ + for (new_tail = g.s; new_tail->next->next; new_tail = new_tail->next) + /* use the opportunity of looping to check if we eat ourselves*/ + if(new_tail->next->r == new_row && new_tail->next->c == new_col) + exit(1); + new_head = new_tail->next; /* reuse element instead of malloc() */ + new_tail->next = NULL; + + new_head->r = new_row; + new_head->c = new_col; + new_head->next = g.s; + + g.s = new_head; +} + +void spawn_item (int type) { + int row, col; +try_again: + row = rand() % g.h; + col = rand() % g.w; + /* loop through snake to check if we aren't on it */ + //TODO: inefficient as snake gets longer; near impossible in the end + for (struct snake* s = g.s; s; s = s->next) + if (s->r == row && s->c == col) goto try_again; + + //3. get item from category TODO + struct item* new_item = malloc (sizeof(struct item)); + new_item->g = "🍎"; + new_item->r = row; + new_item->c = col; + new_item->t = type; + new_item->s = time(0); + if (g.i) g.i->prev = new_item; + new_item->next = g.i; + + g.i = new_item; +} + +void consume_item (struct item* i) { + struct item* predecessor = i->prev; + struct item* successor = i->next; + + if (i->t == FOOD) { + switch (i->t) { + case FOOD: + g.p+=10; //TODO: multiple types for different points? + snake_append(g.s, 0,0); /* position doesn't matter, as item */ + break; /* will be reused as the head before it is drawn */ + case BONUS: + //handle bonus + break; + } + + if (predecessor == NULL) { + g.i = successor; + if (successor) successor->prev = NULL; + } else { + predecessor->next = successor; + successor->prev = predecessor; + } + + free (i); +} + +void show_playfield (void) { + /* top border */ + print("╔═"); + printm (g.w/2-4/2, "══"); + printf ("╡ %04d ╞", g.p); + printm(g.w/2-4/2, "══"); + print ("═╗\n"); + + /* main area */ + for (int row = 0; row < g.h; row++) { + print ("║ "); + printm (g.w, " "); + print (" ║\n"); + } + /* bottom border */ + print("╚═"); + printm (g.w, "══"); + print ("═╝\n"); + + /* print snake */ + struct snake* last = NULL; + for (struct snake* s = g.s; s; s = s->next) { + move_ph (s->r+COL_OFFSET, s->c*CW+LINE_OFFSET); + + int predecessor = (last==NULL)?-1: + (last->r < s->r) ? NORTH: + (last->r > s->r) ? SOUTH: + (last->c > s->c) ? EAST: + (last->c < s->c) ? WEST:-1; + int successor = (s->next == NULL)?-2: + (s->next->r < s->r) ? NORTH: + (s->next->r > s->r) ? SOUTH: + (s->next->c > s->c) ? EAST: + (s->next->c < s->c) ? WEST:-2; + +#define GOES(dir1, dir2) \ + ((predecessor == dir1 || successor == dir1) && \ + (predecessor == dir2 || successor == dir2)) + + /* head (NOTE: direction is inverted in this section) */ + if /*SOUTH*/ GOES(NORTH,-1) print ("⢿⡿"); + else if /*WEST*/ GOES(EAST,-1) print ("⢾⣿"); + else if /*NORTH*/ GOES(SOUTH,-1) print ("⣾⣷"); + else if /*EAST*/ GOES(WEST,-1) print ("⣿⡷"); + /* body */ + else if GOES(NORTH,SOUTH) print ("⡇⢸"); + else if GOES(WEST,EAST) print ("⣉⣉"); + else if GOES(NORTH,EAST) print ("⢇⣈"); + else if GOES(EAST,SOUTH) print ("⡎⢉"); + else if GOES(SOUTH,WEST) print ("⡉⢱"); + else if GOES(WEST,NORTH) print ("⣁⡸"); + /* tail */ + else if GOES(NORTH,-2) print ("⢇⡸"); + else if GOES(EAST,-2) print ("⢎⣉"); + else if GOES(SOUTH,-2) print ("⡎⢱"); + else if GOES(WEST,-2) print ("⣉⡱"); +#undef GOES + last = s; + } + + /* print item queue */ + for (struct item* i = g.i; i; i = i->next) { + move_ph (i->r+LINE_OFFSET, i->c*CW+COL_OFFSET); + print (i->g); + } +} + +void snake_append (struct snake* s, int row, int col) { + struct snake* new = malloc (sizeof(struct snake)); + new->r = row; + new->c = col; + new->next = NULL; + + struct snake* p = s; + while (p->next) p = p->next; + p->next = new; +} + +void init_snake() { + g.s = malloc (sizeof(struct snake)); + g.s->r = g.h/2; + g.s->c = g.w/2; + g.s->next=NULL; + + for (int i = 1; i < op.l; i++) + snake_append(g.s, g.h/2, g.w/2-i); +} + +void quit (void) { + screen_setup(0); + for (struct snake* s = g.s; s;) { + struct snake* tmp = s->next; + free (s); + s = tmp; + } + for (struct item* i = g.i; i;) { + struct item* tmp = i->next; + free (i); + i = tmp; + } +} + +enum esc_states { + START, + ESC_SENT, + CSI_SENT, + MOUSE_EVENT, +}; +int getctrlseq (void) { + int c; + int state = START; + int offset = 0x20; /* never sends control chars as data */ + while ((c = getchar()) != EOF) { + switch (state) { + case START: + switch (c) { + case '\033': state=ESC_SENT; break; + default: return c; + } + break; + case ESC_SENT: + switch (c) { + case '[': state=CSI_SENT; break; + default: return CTRSEQ_INVALID; + } + break; + case CSI_SENT: + switch (c) { + case 'A': return CTRSEQ_CURSOR_UP; + case 'B': return CTRSEQ_CURSOR_DOWN; + case 'C': return CTRSEQ_CURSOR_RIGHT; + case 'D': return CTRSEQ_CURSOR_LEFT; + default: return CTRSEQ_INVALID; + } + break; + default: + return CTRSEQ_INVALID; + } + } + return 2; +} + +void move_ph (int line, int col) { + /* move printhead to zero-indexed position */ + printf ("\033[%d;%dH", line+1, col+1); +} + +void clamp_fieldsize (void) { + /* clamp field size to terminal size and mouse maximum: */ + struct winsize w; + ioctl(STDOUT_FILENO, TIOCGWINSZ, &w); + + if (g.w < 1) g.w = 1; + if (g.h < 1) g.h = 1; + + if (COL_OFFSET + g.w*CW + COL_OFFSET > w.ws_col) + g.w = (w.ws_col - COL_OFFSET - COL_OFFSET)/CW; //TODO: does not work in `-d' (in xterm) + if (LINE_OFFSET + g.h + LINES_AFTER > w.ws_row) + g.h = w.ws_row - (LINE_OFFSET+LINES_AFTER); +} + +void timer_setup (int enable) { + static struct itimerval tbuf; + tbuf.it_interval.tv_sec = 0;//TODO: make configurable, TODO: speed up + tbuf.it_interval.tv_usec = 300000; + + if (enable) { + g.t = time(NULL); + tbuf.it_value.tv_sec = tbuf.it_interval.tv_sec; + tbuf.it_value.tv_usec = tbuf.it_interval.tv_usec; + if (setitimer(ITIMER_REAL, &tbuf, NULL) == -1) { + perror("setitimer"); + exit(1); + } + } else { + tbuf.it_value.tv_sec = 0; + tbuf.it_value.tv_usec = 0; + if ( setitimer(ITIMER_REAL, &tbuf, NULL) == -1 ) { + perror("setitimer"); + exit(1); + } + } + +} + +void signal_setup (void) { + struct sigaction saction; + + saction.sa_handler = signal_handler; + sigemptyset(&saction.sa_mask); + saction.sa_flags = 0; + if (sigaction(SIGALRM, &saction, NULL) < 0 ) { + perror("SIGALRM"); + exit(1); + } + + if (sigaction(SIGINT, &saction, NULL) < 0 ) { + perror ("SIGINT"); + exit (1); + } +} + +void signal_handler (int signum) { + //int dtime; + switch (signum) { + case SIGALRM: + //dtime = difftime (time(NULL), g.t); + //move_ph (1, g.w*CW-(CW%2)-3-(dtime>999)); + //printf ("[%03d]", g.t?dtime:0); + snake_advance(); + break; + case SIGINT: + exit(128+SIGINT); + } +} + +void screen_setup (int enable) { + if (enable) { + raw_mode(1); + printf ("\033[s\033[?47h"); /* save cursor, alternate screen */ + printf ("\033[H\033[J"); /* reset cursor, clear screen */ + printf ("\033[?25l"); /* hide cursor */ + //print (op.scheme->init_seq); /* swich charset, if necessary */ + } else { + //print (op.scheme->reset_seq); /* reset charset, if necessary */ + printf ("\033[?25h"); /* show cursor */ + printf ("\033[?47l\033[u"); /* primary screen, restore cursor */ + raw_mode(0); + } +} + +/* http://users.csc.calpoly.edu/~phatalsk/357/lectures/code/sigalrm.c */ +void raw_mode(int enable) { + static struct termios saved_term_mode; + struct termios raw_term_mode; + + if (enable) { + tcgetattr(STDIN_FILENO, &saved_term_mode); + raw_term_mode = saved_term_mode; + raw_term_mode.c_lflag &= ~(ICANON | ECHO); + raw_term_mode.c_cc[VMIN] = 1 ; + raw_term_mode.c_cc[VTIME] = 0; + tcsetattr(STDIN_FILENO, TCSAFLUSH, &raw_term_mode); + } else { + tcsetattr(STDIN_FILENO, TCSAFLUSH, &saved_term_mode); + } +} -- 2.39.3