We now limit how far ahead you can get. This is measured in screen

widths, and has a command-line option --max-lead.

Also added error checking to command-line parsing.

diff --git a/args.c b/args.c
index 5ee9c35..3a40acd 100644 (file)
--- a/args.c
+++ b/args.c
@@ -1,13 +1,18 @@
+#include <errno.h>
 #include "args.h"
 #include "config.h"
 
+// Gameplay Variations
+float opt_bounciness;
+float opt_gamespeed;
+float opt_max_lead;
+int opt_friction;
+
+// Look and Feel
 int opt_fullscreen;
 int opt_music;
 int opt_sound;
-float opt_bounciness;
-float opt_gamespeed;
 int opt_tail_engine;
-int opt_friction;
 
 error_t parse_opt(int, char*, struct argp_state *);
 
@@ -16,14 +21,15 @@ const char *argp_program_bug_address = "<josh@qualdan.com>";
 static char doc[] = "Dodge the rocks until you die.";
 static struct argp_option opts[] = {
        {0, 0, 0, 0, "Gameplay Variations:"},
-       {"bounciness", 'b', "N%", 0, "keep N% of speed when hitting edges (default 50%)"},
+       {"bounciness", 'b', "N%", 0, "Keep N% of speed when hitting edges (default 50%)"},
        {"game-speed", 'g', "N%", 0, "50-100% (default 100%)"},
-       {"bad-physics", 'p', 0, 0, "bad physics (i.e. friction)"},
+       {"max-lead", 'l', "#SCREENS", 0, "Max dist. ahead you can get (default 1 screen)\n(negative value means no limit)"},
+       {"bad-physics", 'p', 0, 0, "Bad physics (i.e. friction)"},
        {0, 0, 0, 0, "Look and Feel:"},
        {"engine", 'e', 0, 0, "Display large tail plume"},
        {"full-screen", 'f', 0, 0, ""},
        {"music", 'm', 0, 0, "Enable music"},
-       {"silent", 's', 0, 0, "Turn off explosion sounds"},
+       {"silent", 's', 0, 0, "No explosion sounds or music"},
        {0, 0, 0, 0, "Informational:", -1},
        {0}
 };
@@ -33,14 +39,17 @@ struct argp argp = { opts, &parse_opt, 0, doc };
 void
 init_opts(void)
 {
+       // Gameplay Variations
+       opt_bounciness = 0.50; // lose 50% when you hit the screen edge.
+       opt_gamespeed = 1.00; // Run game at full speed.
+       opt_max_lead = 1.00*XSIZE;  // you can get 1 screen ahead.
+       opt_friction = 0;
+
+       // Look and Feel
        opt_fullscreen = 0;
        opt_sound = 1;
        opt_music = 0;
-       opt_bounciness = 0.50; // lose 50% when you hit the screen edge.
-       opt_gamespeed = 1.00; // Run game at full speed.
-       // These switch back to the old gameplay and are off by default.
        opt_tail_engine = 0;
-       opt_friction = 0;
 }
 
 error_t
@@ -49,19 +58,31 @@ parse_opt(int key, char *arg, struct argp_state *state)
        int i;
 
        switch(key) {
-               case 'f': opt_fullscreen = 1; break;
-               case 'm': opt_music = 1; break;
-               case 's': opt_sound = 0; opt_music = 0; break;
-               case 'b': i = 0; sscanf(arg, "%d%%", &i);
+               case 'b': if(!sscanf(arg, "%d%%", &i)) {
+                                         argp_error(state, "bad --bounciness (-b) value (should be 0-100%%)");
+                                         return EINVAL;
+                                 }
                                  if(i < 50) i = 50; else if(i > 100) i = 100;
                                  opt_bounciness = (float)i / 100;
                                  break;
-               case 'g': i = 0; sscanf(arg, "%d%%", &i);
+               case 'e': opt_tail_engine = 1; break;
+               case 'f': opt_fullscreen = 1; break;
+               case 'g': if(!sscanf(arg, "%d%%", &i)) {
+                                         argp_error(state, "bad --gamespeed (-g) value (should be 50-100%%)");
+                                         return EINVAL;
+                                 }
                                  if(i < 0) i = 0; else if(i > 100) i = 100;
                                  opt_gamespeed = (float)i / 100;
                                  break;
-               case 'e': opt_tail_engine = 1; break;
+               case 'l': if(!sscanf(arg, "%f", &opt_max_lead)) {
+                                         argp_error(state, "bad --max-limit (-l) value (must be a number)");
+                                         return EINVAL;
+                                 }
+                                 opt_max_lead *= XSIZE;
+                                 break;
+               case 'm': opt_music = 1; break;
                case 'p': opt_friction = 1; break;
+               case 's': opt_sound = 0; opt_music = 0; break;
                default: break;
        }
        return 0;

diff --git a/args.h b/args.h
index 4f04d27..c2d05c6 100644 (file)
--- a/args.h
+++ b/args.h
@@ -3,13 +3,17 @@
 
 #include <argp.h>
 
+// Gameplay Variations
+extern float opt_bounciness;
+extern float opt_gamespeed;
+extern float opt_max_lead;
+extern int opt_friction;
+
+// Look and Feel
 extern int opt_fullscreen;
 extern int opt_music;
 extern int opt_sound;
-extern float opt_bounciness;
-extern float opt_gamespeed;
 extern int opt_tail_engine;
-extern int opt_friction;
 
 struct argp argp;
 

diff --git a/common.h b/common.h
new file mode 100644 (file)
index 0000000..ac9d87e
--- /dev/null
+++ b/common.h
@@ -0,0 +1,28 @@
+#ifndef VOR_COMMON_H
+#define VOR_COMMON_H
+
+#ifndef NULL
+#define NULL 0
+#endif
+
+#ifndef true
+#define true 1
+#endif
+
+#ifndef false
+#define false 0
+#endif
+
+#ifndef max
+#define max(a, b) ((a) > (b) ? (a) : (b))
+#endif
+
+#ifndef min
+#define min(a, b) ((a) < (b) ? (a) : (b))
+#endif
+
+#ifndef abs
+#define abs(a) ((a)<=0 ? -(a) : (a))
+#endif
+
+#endif // VOR_COMMON_H

diff --git a/main.c b/main.c
index c2e6601..a2bdcbc 100644 (file)
--- a/main.c
+++ b/main.c
@@ -19,11 +19,23 @@
  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
  */
 
+#include <argp.h>
+#include <math.h>
+#include <SDL/SDL.h>
+#include <SDL/SDL_image.h>
+#include <stdarg.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+
+#include "SFont.h"
+
 #ifdef DEBUG
 #include "debug.h"
 #endif
 
 #include "args.h"
+#include "common.h"
 #include "config.h"
 #include "file.h"
 #include "globals.h"
@@ -32,17 +44,6 @@
 #include "shape.h"
 #include "sound.h"
 
-#include <argp.h>
-#include <math.h>
-#include <SDL/SDL.h>
-#include <SDL/SDL_image.h>
-#include <stdarg.h>
-#include <stdio.h>
-#include <stdlib.h>
-#include <string.h>
-
-#include "SFont.h"
-
 // ************************************* VARS
 // SDL_Surface global variables
 SDL_Surface 
@@ -116,6 +117,8 @@ char *data_dir;
 extern char *optarg;
 extern int optind, opterr, optopt;
 
+#define TO_TICKS(seconds) ((seconds)*20*opt_gamespeed)
+
 // ************************************* FUNCS
 
 float
@@ -714,13 +717,14 @@ gameloop() {
                        screendx = -tmp;
 
                        // taper off if we would hit the barrier in under 2 seconds.
-                       if(back_dist + (screendx - SCREENDXMIN)*2*20*opt_gamespeed < 0) {
-                               screendx = SCREENDXMIN - (back_dist/(2*20*opt_gamespeed));
+                       if(back_dist + (screendx - SCREENDXMIN)*TO_TICKS(2) < 0) {
+                               screendx = SCREENDXMIN - (back_dist/TO_TICKS(2));
                        }
 
                        xscroll = screendx * framelen;
                        yscroll = screendy * framelen;
                        back_dist += (screendx - SCREENDXMIN)*framelen;
+                       if(opt_max_lead >= 0) back_dist = min(back_dist, opt_max_lead);
 
                        shipx -= xscroll;
                        shipy -= yscroll;

diff --git a/shape.c b/shape.c
index 9e03f19..f457158 100644 (file)
--- a/shape.c
+++ b/shape.c
@@ -1,4 +1,5 @@
 #include <stdlib.h>
+#include "common.h"
 #include "shape.h"
 
 void
@@ -39,18 +40,6 @@ get_shape(SDL_Surface *img, struct shape *s)
        SDL_UnlockSurface(img);
 }
 
-#ifndef max
-#define max(a, b) ((a) > (b) ? (a) : (b))
-#endif
-
-#ifndef min
-#define min(a, b) ((a) < (b) ? (a) : (b))
-#endif
-
-#ifndef abs
-#define abs(a) ((a)<=0 ? -(a) : (a))
-#endif
-
 int
 line_collide(int xov, struct shape *r, uint32_t *rbits, struct shape *s, uint32_t *sbits)
 {