1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
|
#include <stdio.h>
#include <stdlib.h>
#include <SDL2/SDL.h>
#include "chip8.h"
/* references
* https://austinmorlan.com/posts/chip8_emulator/
* http://www.multigesture.net/articles/how-to-write-an-emulator-chip-8-interpreter/
* http://mattmik.com/files/chip8/mastering/chip8.html (lots of info)
* http://devernay.free.fr/hacks/chip8/C8TECH10.HTM#0.1
* http://www.emulator101.com/chip-8-sprites.html
*/
#define VIDEO_SCALE 10
SDL_Window *window;
SDL_Renderer *renderer;
SDL_Texture *texture;
void init_video();
void update_video();
void toggle_pixel(int x, int y);
void quit();
void usage(char *);
extern uint32_t video[WIDTH*HEIGHT];
extern int draw_flag;
void
usage(char *program)
{
printf("usage: %s [romfile]\n", program);
}
void
quit()
{
SDL_DestroyTexture(texture);
SDL_DestroyRenderer(renderer);
SDL_DestroyWindow(window);
SDL_Quit();
}
void
init_video()
{
SDL_Init(SDL_INIT_VIDEO);
window = SDL_CreateWindow("chip8 interpreter", 0, 0, WIDTH*VIDEO_SCALE, HEIGHT*VIDEO_SCALE, SDL_WINDOW_SHOWN);
renderer = SDL_CreateRenderer(window, -1, SDL_RENDERER_ACCELERATED);
texture = SDL_CreateTexture(renderer, SDL_PIXELFORMAT_RGBA32, SDL_TEXTUREACCESS_STREAMING, WIDTH, HEIGHT);
}
void
update_video()
{
static int count = 0;
//printf("frame %d\n", count++);
/*
for (uint32_t i = 0 ;i < WIDTH*HEIGHT; i++)
{
video[i] = (255<<16)|(255<<8)|255;
}
video[0] = (255);
video[1] = (255<<8);
video[2] = (255<<16);
*/
SDL_UpdateTexture(texture, NULL, video, sizeof(video[0])*WIDTH);
SDL_RenderClear(renderer);
SDL_RenderCopy(renderer, texture, NULL, NULL);
SDL_RenderPresent(renderer);
}
void
toggle_pixel(int x, int y)
{
// TODO: clean
uint32_t dos = video[WIDTH*y+x];
if (dos <= 0)
video[WIDTH*y+x] = (255<<16)|(255<<8)|255;
else
video[WIDTH*y+x] = 0;
}
int main(int argc, char *argv[])
{
if (argc < 2)
{
usage(argv[0]);
exit(EXIT_FAILURE);
}
if (!load_rom(argv[1]))
{
fprintf(stderr, "cannot start interpreter\n");
exit(EXIT_FAILURE);
}
chip8_init();
init_video();
const int fps = 60;
const int frame_delay = 1000/fps;
uint32_t frame_start;
uint32_t frame_time;
int do_quit = 0;
chip8_draw_sprite(0, 0, 0xD*5, 0x5);
chip8_draw_sprite(5, 0, 0xE*5, 0x5);
chip8_draw_sprite(10, 0, 0xA*5, 0x5);
chip8_draw_sprite(15, 0, 0xD*5, 0x5);
chip8_draw_sprite(20, 0, 0xB*5, 0x5);
chip8_draw_sprite(25, 0, 0xE*5, 0x5);
chip8_draw_sprite(30, 0, 0xE*5, 0x5);
chip8_draw_sprite(35, 0, 0xf*5, 0x5);
chip8_draw_sprite(0, 9, 0xD*5, 0x5);
chip8_draw_sprite(5, 9, 0xE*5, 0x5);
chip8_draw_sprite(10, 9, 0xA*5, 0x5);
chip8_draw_sprite(15, 9, 0xD*5, 0x5);
chip8_draw_sprite(20, 9, 0xB*5, 0x5);
chip8_draw_sprite(25, 9, 0xE*5, 0x5);
chip8_draw_sprite(30, 9, 0xE*5, 0x5);
chip8_draw_sprite(35, 9, 0xf*5, 0x5);
while(!do_quit)
{
frame_start = SDL_GetTicks();
// logic
update_video();
frame_time = SDL_GetTicks() - frame_start;
if (frame_delay > frame_time)
{
SDL_Delay(frame_delay - frame_time);
}
}
quit();
return EXIT_SUCCESS;
}
|
