#include <stdlib.h>
#include <string.h>
+#include "common.h"
#include "config.h"
#include "file.h"
#include "globals.h"
+#include "mt.h"
#include "rocks.h"
#include "shape.h"
float rtimers[4];
uint32_t nrocks;
-uint32_t nrocks_timer;
-uint32_t nrocks_inc_ticks = 2*60*1000/(F_ROCKS-I_ROCKS);
+float nrocks_timer;
+float nrocks_inc_ticks = 2*60*20/(F_ROCKS-I_ROCKS);
// 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 KH (32.0*20) // 32 s for a speed=1 rock to cross the screen horizontally.
+#define KV (24.0*20) // 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);
-
-#define crnd() (2*(rnd()-0.5))
-
-
int
init_rocks(void)
{
NULLERROR(surf_rock[i] = SDL_DisplayFormat(temp));
get_shape(surf_rock[i], &rock_shapes[i]);
}
+ reset_rocks();
return 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_timer_increments(float *ti)
+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;
- hfactor = nrocks/KH; vfactor = nrocks/KV;
+ 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) {
- if(dx0 < 0) {
- if(dx1 < 0) ti[RIGHT] = -(dx0+dx1)/2;
- else {
- ti[RIGHT] = -dx0/2;
- ti[LEFT] = dx1/2;
- }
- } else ti[LEFT] = (dx0+dx1)/2;
+ 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;
+ }
+ } else {
+ // Rocks moving right only. So the LEFT side of the screen
+ speed_min[LEFT] = dx0;
+ speed_max[LEFT] = dx1;
+ 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;
+ if(dy0 < 0) {
+ speed_max[BOTTOM] = -dy0;
+ if(dy1 < 0) {
+ // Rocks moving up only. So the BOTTOM of the screen
+ speed_min[BOTTOM] = -dy1;
+ ti[BOTTOM] = -(dy0+dy1)/2;
+ } else {
+ // Rocks moving up and down
+ speed_max[TOP] = dy1;
+ ti[BOTTOM] = -dy0/2;
+ ti[TOP] = dy1/2;
+ }
+ } else {
+ // Rocks moving down only. so the TOP of the screen
+ speed_min[TOP] = dy0;
+ speed_max[TOP] = dy1;
+ ti[TOP] = (dy0+dy1)/2;
}
ti[TOP] *= vfactor;
ti[BOTTOM] *= vfactor;
}
+float
+weighted_rnd_range(float min, float max) {
+ return sqrt(min * min + frnd() * (max * max - min * min));
+}
+
void
new_rocks(void)
{
int i,j;
float ti[4];
+ float rmin[4];
+ float rmax[4];
if(nrocks < F_ROCKS) {
- nrocks_timer += ticks_since_last;
+ nrocks_timer += t_frame;
if(nrocks_timer >= nrocks_inc_ticks) {
nrocks_timer -= nrocks_inc_ticks;
nrocks++;
}
}
- rock_timer_increments(ti);
+ rock_sides(ti, rmin, rmax);
+ // loop through the four sides of the screen
for(i=0; i<4; i++) {
- rtimers[i] += ti[i]*gamerate/20;
- if(rtimers[i] >= 1) {
+ // see if we generate a rock for this side this frame
+ rtimers[i] += ti[i]*t_frame;
+ while(rtimers[i] >= 1) {
+ 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);
+ rockptr->y = frnd()*(YSIZE + rockptr->image->h);
+
+ rockptr->dx = -weighted_rnd_range(rmin[i], rmax[i]) + screendx;
+ rockptr->dy = RDY*crnd();
break;
case LEFT:
rockptr->x = -rockptr->image->w;
- rockptr->y = rnd()*(YSIZE + rockptr->image->h);
+ rockptr->y = frnd()*(YSIZE + rockptr->image->h);
+
+ rockptr->dx = weighted_rnd_range(rmin[i], rmax[i]) + screendx;
+ rockptr->dy = RDY*crnd();
break;
case BOTTOM:
- rockptr->x = rnd()*(XSIZE + rockptr->image->w);
+ rockptr->x = frnd()*(XSIZE + rockptr->image->w);
rockptr->y = YSIZE;
+
+ rockptr->dx = RDX*crnd();
+ rockptr->dy = -weighted_rnd_range(rmin[i], rmax[i]) + screendy;
break;
case TOP:
- rockptr->x = rnd()*(XSIZE + rockptr->image->w);
+ rockptr->x = frnd()*(XSIZE + rockptr->image->w);
rockptr->y = -rockptr->image->h;
+
+ rockptr->dx = RDX*crnd();
+ rockptr->dy = weighted_rnd_range(rmin[i], rmax[i]) + screendy;
break;
}
- rockptr->dx = RDX*crnd();
- rockptr->dy = RDY*crnd();
-
rockptr->active = 1;
}
}
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;
+ rock[i].x += (rock[i].dx-screendx)*t_frame;
+ rock[i].y += (rock[i].dy-screendy)*t_frame;
// clip
if(rock[i].x < -rock[i].image->w || rock[i].x >= XSIZE
|| rock[i].y < -rock[i].image->h || rock[i].y >= YSIZE) {