- if(--countdown <= 0 && (rnd()*100.0<(rockrate += 0.025))) {
- // Possibly create a rock
- rockptr++;
- if(rockptr-rock >= MAXROCKS) {
- rockptr = rock;
- }
- if(!rockptr->active) {
- rockptr->dx = -(rockspeed)*(1 + rnd());
- rockptr->dy = rnd()-0.5;
- rockptr->type_number = random() % NROCKS;
- rockptr->image = surf_rock[rockptr->type_number];
- rockptr->shape = &rock_shapes[rockptr->type_number];
- rockptr->x = (float)XSIZE;
- rockptr->y = rnd()*(YSIZE + rockptr->image->h);
- rockptr->active = 1;
- area += rockptr->shape->area;
+ int i;
+
+ for(i = 0; i<MAXROCKS; i++) rock[i].active = 0;
+ nrocks = I_ROCKS;
+ nrocks_timer = 0;
+}
+
+enum { LEFT, RIGHT, TOP, BOTTOM };
+
+
+// compute the number of rocks/second that should be coming from each side
+
+// compute the speed ranges of rocks coming from each side
+void
+rock_sides(float *ti, float *speed_min, float *speed_max)
+{
+ float dx0,dx1, dy0,dy1;
+ float hfactor, vfactor;
+ int i;
+
+ for(i=0; i<4; i++) ti[i] = 0;
+ for(i=0; i<4; i++) speed_min[i] = 0;
+ for(i=0; i<4; i++) speed_max[i] = 0;
+ hfactor = (float)nrocks/KH; vfactor = (float)nrocks/KV;
+
+ dx0 = -RDX - screendx; dx1 = RDX - screendx;
+ dy0 = -RDY - screendy; dy1 = RDY - screendy;
+
+ if(dx0 < 0) {
+ speed_max[RIGHT] = -dx0;
+ if(dx1 < 0) {
+ // Rocks moving left only. So the RIGHT side of the screen
+ speed_min[RIGHT] = -dx1;
+ ti[RIGHT] = -(dx0+dx1)/2;
+ } else {
+ // Rocks moving left and right
+ speed_max[LEFT] = dx1;
+ ti[RIGHT] = -dx0/2;
+ ti[LEFT] = dx1/2;