dos33fsprogs/utils/gr-sim/plasma/plasma.c
2021-01-09 01:41:44 -05:00

89 lines
1.5 KiB
C

/* for demoscene, you need a plasma effect... */
/* https://rosettacode.org/wiki/Plasma_effect */
/* https://www.bidouille.org/prog/plasma */
#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <math.h>
#include "tfv_zp.h"
#include "gr-sim.h"
#define PI 3.14159265358979323846264338327950
#if 1
static unsigned char color_lookup[]={0x0, 0x0, 0x5, 0x5,
0x7, 0x7, 0xf, 0xf,
0x7, 0x7, 0x6, 0x6,
0x2, 0x2, 0x5, 0x5};
#else
static unsigned char color_lookup[]={0x0, 0x5, 0x7, 0xf,
0x7, 0x6, 0x2, 0x5,
0x0, 0x5, 0x7, 0xf,
0x7, 0x6, 0x2, 0x5};
#endif
static int offscreen[40][40];
int main(int argc, char **argv) {
int ch,xx,yy,col;
grsim_init();
gr();
soft_switch(MIXCLR);
clear_screens();
ram[DRAW_PAGE]=0x0;
for(yy=0;yy<40;yy++) {
for(xx=0;xx<40;xx++) {
// col = ( 32.0 + (32.0 * sin(xx / 4.0))
// + 32.0 + (32.0 * sin(yy / 4.0))
// ) / 2;
col = ( 8.0 + (8.0 * sin(xx *PI/8.0))
+ 8.0 + (8.0 * sin(yy *PI/8.0))
) / 2;
offscreen[xx][yy]=col;
}
}
while(1) {
for(yy=0;yy<40;yy++) {
for(xx=0;xx<40;xx++) {
col=offscreen[xx][yy];
color_equals(color_lookup[col]);
col++;
col&=0xf;
offscreen[xx][yy]=col;
plot(xx,yy);
}
}
grsim_update();
ch=grsim_input();
if (ch=='q') exit(0);
if (ch==' ') {
while(1) {
ch=grsim_input();
if (ch) break;
}
}
usleep(200000);
}
return 0;
}