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#include <SDL_image.h>
#include <math.h>
#include <stdlib.h>
#include <string.h>
#include "common.h"
#include "vorconfig.h"
#include "file.h"
#include "globals.h"
#include "mt.h"
#include "rocks.h"
#include "sprite.h"
static struct rock rocks[MAXROCKS];
static struct rock prototypes[NROCKS];
// timers for rock generation.
static float rtimers[4];
uint32_t nrocks = NORMAL_I_ROCKS;
uint32_t initial_rocks = NORMAL_I_ROCKS;
uint32_t final_rocks = NORMAL_F_ROCKS;
float nrocks_timer = 0;
float nrocks_inc_ticks = 2*60*20/(NORMAL_F_ROCKS-NORMAL_I_ROCKS);
// constants for rock generation.
#define KH (32*20) // 32 s for a speed=1 rock to cross the screen horizontally.
#define KV (24*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 (+/-)
void
reset_rocks(void)
{
nrocks = initial_rocks;
nrocks_inc_ticks = 2*60*20/(final_rocks-initial_rocks);
nrocks_timer = 0;
}
#define ROCK_LEN sizeof("rockXX.png")
void
load_rocks(void)
{
int i;
char a[ROCK_LEN];
for(i=0; i<NROCKS; i++) {
snprintf(a, ROCK_LEN, "rock%02d.png", i);
load_sprite(SPRITE(&prototypes[i]), a);
prototypes[i].sprite_type = ROCK;
prototypes[i].flags = MOVE|DRAW|COLLIDE;
}
memset(rocks, 0, MAXROCKS*sizeof(struct rock));
for(i=1; i<MAXROCKS; i++) rocks[i].next = &rocks[i-1];
free_sprites[ROCK] = SPRITE(&rocks[MAXROCKS-1]);
reset_rocks();
}
enum { LEFT, RIGHT, TOP, BOTTOM };
// compute the number of rocks/tick that should be coming from each side,
// and 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;
}
} 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) {
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, type;
struct rock *r;
float ti[4];
float rmin[4];
float rmax[4];
if(nrocks < final_rocks) {
nrocks_timer += t_frame;
if(nrocks_timer >= nrocks_inc_ticks) {
nrocks_timer -= nrocks_inc_ticks;
nrocks++;
}
}
rock_sides(ti, rmin, rmax);
// increment timers
for(i=0; i<4; i++) rtimers[i] += ti[i]*t_frame;
// generate rocks
for(i=0; i<4; i++) {
while(rtimers[i] >= 1) {
rtimers[i] -= 1;
if(!free_sprites[ROCK]) return; // sorry, we ran out of rocks!
r = (struct rock *) remove_sprite(&free_sprites[ROCK]);
type = urnd() % NROCKS;
*r = prototypes[type];
r->type = type;
switch(i) {
case RIGHT:
r->x = XSIZE;
r->y = frnd()*(YSIZE + r->image->h);
r->dx = -weighted_rnd_range(rmin[i], rmax[i]) + screendx;
r->dy = RDY*crnd();
break;
case LEFT:
r->x = -r->image->w;
r->y = frnd()*(YSIZE + r->image->h);
r->dx = weighted_rnd_range(rmin[i], rmax[i]) + screendx;
r->dy = RDY*crnd();
break;
case BOTTOM:
r->x = (frnd()*(XSIZE + r->image->w)) - r->image->w;
r->y = YSIZE;
r->dx = RDX*crnd();
r->dy = -weighted_rnd_range(rmin[i], rmax[i]) + screendy;
break;
case TOP:
r->x = (frnd() * (XSIZE + r->image->w)) - r->image->w;
r->y = -r->image->h;
r->dx = RDX*crnd();
r->dy = weighted_rnd_range(rmin[i], rmax[i]) + screendy;
break;
}
add_sprite(SPRITE(r));
}
}
}
void
draw_rocks(void)
{
int i;
for(i=0; i<MAXROCKS; i++) draw_sprite(SPRITE(&rocks[i]));
}
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