mirror of
https://github.com/sehugg/8bitworkshop.git
synced 2024-11-25 18:33:11 +00:00
98 lines
2.2 KiB
C
98 lines
2.2 KiB
C
|
|
//this example shows how to set up a palette and use 8x8 HW sprites
|
|
//also shows how fast (or slow) C code is
|
|
|
|
#include "neslib.h"
|
|
|
|
#pragma data-name (push,"CHARS")
|
|
#pragma data-name(pop)
|
|
|
|
//#link "tileset1.c"
|
|
|
|
// palette for balls, there are four sets for different ball colors
|
|
extern unsigned char palSprites[16];
|
|
|
|
// tile set, two planes for 4 colors
|
|
extern unsigned char TILESET[8*256];
|
|
|
|
//general purpose vars
|
|
static unsigned char i,j;
|
|
static unsigned char spr;
|
|
|
|
//total number of balls on the screen
|
|
//since there are 64 HW sprites, it is absolute max
|
|
|
|
#define BALLS_MAX 64
|
|
|
|
//balls parameters
|
|
|
|
static unsigned char ball_x[BALLS_MAX];
|
|
static unsigned char ball_y[BALLS_MAX];
|
|
static unsigned char ball_dx[BALLS_MAX];
|
|
static unsigned char ball_dy[BALLS_MAX];
|
|
|
|
|
|
|
|
|
|
|
|
void main(void)
|
|
{
|
|
//copy tileset to RAM
|
|
vram_adr(0x0);
|
|
vram_write((unsigned char*)TILESET, sizeof(TILESET));
|
|
|
|
pal_spr(palSprites);//set palette for sprites
|
|
oam_size(1);
|
|
ppu_on_all();//enable rendering
|
|
|
|
//initialize balls parameters
|
|
|
|
for(i=0;i<BALLS_MAX;++i)
|
|
{
|
|
//starting coordinates
|
|
|
|
ball_x[i]=rand8();
|
|
ball_y[i]=rand8();
|
|
|
|
//direction bits
|
|
|
|
j=rand8();
|
|
|
|
//horizontal speed -3..-3, excluding 0
|
|
spr=1+(rand8()%3);
|
|
ball_dx[i]=j&1?-spr:spr;
|
|
|
|
//vertical speed
|
|
|
|
spr=1+(rand8()%3);
|
|
ball_dy[i]=j&2?-spr:spr;
|
|
}
|
|
|
|
|
|
//now the main loop
|
|
|
|
while(1)
|
|
{
|
|
ppu_wait_nmi();//wait for next TV frame
|
|
|
|
spr=0;
|
|
|
|
for(i=0;i<BALLS_MAX;++i)
|
|
{
|
|
//set a sprite for current ball
|
|
|
|
spr=oam_spr(ball_x[i],ball_y[i],0x40,i&3,spr);//0x40 is tile number, i&3 is palette
|
|
|
|
//move the ball
|
|
|
|
ball_x[i]+=ball_dx[i];
|
|
ball_y[i]+=ball_dy[i];
|
|
|
|
//bounce the ball off the edges
|
|
|
|
if(ball_x[i]>=(256-8)) ball_dx[i]=-ball_dx[i];
|
|
if(ball_y[i]>=(240-8)) ball_dy[i]=-ball_dy[i];
|
|
}
|
|
}
|
|
}
|