X-Git-Url: https://jasonwoof.com/gitweb/?p=vor.git;a=blobdiff_plain;f=rocks.c;h=565397924379aab64e07418827bc83cdbdd06896;hp=fe66c4c3ba5bdc4effced5b5859c9cb06b53defb;hb=0179e60b6196d115000cb77fcd4cc880eecb177f;hpb=46dacbe75dac20a1c6e1b61a2eb99ca25fc971ec

diff --git a/rocks.c b/rocks.c
index fe66c4c..5653979 100644
--- a/rocks.c
+++ b/rocks.c
@@ -12,8 +12,6 @@
 struct rock_struct {
 	float x,y,dx,dy;
 	int active;
-	int dead;  // has been blown out of the way
-	           // to make room for a new ship appearing.
 	SDL_Surface *image;
 	struct shape *shape;
 	int type_number;
@@ -21,16 +19,23 @@ struct rock_struct {
 
 struct rock_struct rock[MAXROCKS], *rockptr = rock;
 
-float rockrate,rockspeed;
-
 SDL_Surface *surf_rock[NROCKS];
 struct shape rock_shapes[NROCKS];
 
-int countdown = 0;
+// timers for rock generation.
+float rtimers[4];
+int nrocks;
+
+// constants for rock generation.
+#define KH 32.0  // 32 s for a speed=1 rock to cross the screen horizontally.
+#define KV 24.0  // 24 s for a speed=1 rock to cross the screen vertically.
+#define RDX 2.5  // range for rock dx values (+/-)
+#define RDY 2.5  // range for rock dy values (+/-)
 
 float rnd(void);
 
-uint32_t area;
+#define crnd() (2*(rnd()-0.5))
+
 
 int
 init_rocks(void)
@@ -39,88 +44,131 @@ init_rocks(void)
 	char a[MAX_PATH_LEN];
 	SDL_Surface *temp;
 
-	area = 0;
-
 	for(i = 0; i<NROCKS; i++) {
 		snprintf(a,MAX_PATH_LEN,add_path("sprites/rock%02d.png"),i);
 		NULLERROR(temp = IMG_Load(a));
 		NULLERROR(surf_rock[i] = SDL_DisplayFormat(temp));
 		get_shape(surf_rock[i], &rock_shapes[i]);
 	}
+	nrocks = 41;
 	return 0;
 }
 
 void
-new_rocks(void)
+reset_rocks(void)
 {
-	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;
-		}
-		if(gamerate>0.1) {
-			countdown = (int)(ROCKRATE/gamerate);
-		} else {
-			countdown = 0;
-		}
-	}
+	int i;
+
+	for(i = 0; i<MAXROCKS; i++) rock[i].active = 0;
 }
 
+enum { LEFT, RIGHT, TOP, BOTTOM };
+
 void
-move_rocks(void)
+rock_timer_increments(float *ti)
 {
+	float dx0,dx1, dy0,dy1;
+	float hfactor, vfactor;
 	int i;
 
-	// Move all the rocks
-	for(i = 0; i < MAXROCKS; i++) {
-		if(rock[i].active) {
-			rock[i].x += rock[i].dx*gamerate;
-			rock[i].y += rock[i].dy*gamerate + yscroll;
-			if(rock[i].y > YSIZE || rock[i].y < -rock[i].image->h) {
-				if(rock[i].dead) {
-					area -= rock[i].shape->area;
-					rock[i].dead = 0;
-					rock[i].active = 0;
-				} else {
-					// wrap
-					rock[i].y = (YSIZE - rock[i].image->h) - rock[i].y;
-					rock[i].y += (rock[i].dy*gamerate + yscroll) * 1.01;
-				}
+	for(i=0; i<4; i++) ti[i] = 0;
+	hfactor = nrocks/KH; vfactor = nrocks/KV;
+
+	dx0 = -RDX - screendx; dx1 = RDX - screendx;
+	dy0 = -RDY - screendy; dy1 = RDY - screendy;
+
+	if(dx0 != 0) {
+		if(dx0 < 0) {
+			if(dx1 < 0) ti[RIGHT] = -(dx0+dx1)/2;
+			else {
+				ti[RIGHT] = -dx0/2;
+				ti[LEFT] = dx1/2;
 			}
-			if(rock[i].x < -rock[i].image->w || rock[i].x > XSIZE) {
-				area -= rock[i].shape->area;
-				rock[i].active = 0;
-				rock[i].dead = 0;
+		} else ti[LEFT] = (dx0+dx1)/2;
+	}
+	ti[LEFT] *= hfactor;
+	ti[RIGHT] *= hfactor;
+
+	if(dy0 != 0) {
+		if(dy0 < 0) {
+			if(dy1 < 0) ti[BOTTOM] = -(dy0+dy1)/2;
+			else {
+				ti[BOTTOM] = -dy0/2;
+				ti[TOP] = dy1/2;
+			}
+		} else ti[TOP] = (dy0+dy1)/2;
+	}
+	ti[TOP] *= vfactor;
+	ti[BOTTOM] *= vfactor;
+}
+
+void
+new_rocks(void)
+{
+	int i,j;
+	float ti[4];
+
+	rock_timer_increments(ti);
+
+	for(i=0; i<4; i++) {
+		rtimers[i] += ti[i]*gamerate/20;
+		if(rtimers[i] >= 1) {
+			j=0;
+			while(rockptr->active && j<MAXROCKS) {
+				if(++rockptr - rock >= MAXROCKS) rockptr = rock;
+				j++;
+			}
+			if(!rockptr->active) {
+				rtimers[i] -= 1;
+				rockptr->type_number = random() % NROCKS;
+				rockptr->image = surf_rock[rockptr->type_number];
+				rockptr->shape = &rock_shapes[rockptr->type_number];
+				switch(i) {
+					case RIGHT:
+						rockptr->x = XSIZE;
+						rockptr->y = rnd()*(YSIZE + rockptr->image->h);
+						break;
+					case LEFT:
+						rockptr->x = -rockptr->image->w;
+						rockptr->y = rnd()*(YSIZE + rockptr->image->h);
+						break;
+					case BOTTOM:
+						rockptr->x = rnd()*(XSIZE + rockptr->image->w);
+						rockptr->y = YSIZE;
+						break;
+					case TOP:
+						rockptr->x = rnd()*(XSIZE + rockptr->image->w);
+						rockptr->y = -rockptr->image->h;
+						break;
+				}
+
+				rockptr->dx = RDX*crnd();
+				rockptr->dy = RDY*crnd();
+
+				rockptr->active = 1;
 			}
 		}
 	}
 }
 
 void
-reset_rocks(void)
+move_rocks(void)
 {
 	int i;
 
-	area = 0;
-	for(i = 0; i<MAXROCKS; i++ ) {
-		rock[i].active = 0;
-		rock[i].dead = 0;
+	// Move all the rocks
+	for(i = 0; i < MAXROCKS; i++) {
+		if(rock[i].active) {
+			// move
+			rock[i].x += (rock[i].dx-screendx)*gamerate;
+			rock[i].y += (rock[i].dy-screendy)*gamerate;
+			// clip
+			if(rock[i].x < -rock[i].image->w || rock[i].x >= XSIZE
+					|| rock[i].y < -rock[i].image->h || rock[i].y >= YSIZE) {
+				rock[i].active = 0;
+			}
+		}
 	}
-
-	rockrate = 54.0;
-	rockspeed = 5.0;
 }
 
 void
@@ -173,9 +221,7 @@ blast_rocks(float x, float y, float radius, int onlyslow)
 		// This makes it so your explosion from dying magically doesn't leave
 		// any rocks that aren't moving much on the x axis. If onlyslow is set,
 		// only rocks that are barely moving will be pushed.
-		if(onlyslow && (!rock[i].dead || rock[i].dx < -4 || rock[i].dx > 3)) {
-			continue;
-		}
+		if(onlyslow && (rock[i].dx-screendx < -4 || rock[i].dx-screendx > 3)) continue;
 
 		dx = rock[i].x - x;
 		dy = rock[i].y - y;
@@ -183,9 +229,8 @@ blast_rocks(float x, float y, float radius, int onlyslow)
 		n = sqrt(dx*dx + dy*dy);
 		if(n < radius) {
 			n *= 20;
-			rock[i].dx += rockrate*(dx+30)/n;
-			rock[i].dy += rockrate*dy/n;
-			rock[i].dead = 1;
+			rock[i].dx += 54.0*(dx+30)/n;
+			rock[i].dy += 54.0*dy/n;
 		}
 	}
 }