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#include <string.h>
#include "common.h"
#include "bitmap.h"
#include "text.h"
#include "small-font.c"
#include "uxn/uxn.h"
#include "uxn/uxn.c"
#include "uxn/devices/ppu.h"
#include "uxn/devices/ppu.c"
// #include "uxn/roms/console.c"
#include "uxn/roms/dvd.c"
// #include "uxn/roms/proportional_fonts.c"
// #include "uxn/roms/automata.c"
// #include "uxn/roms/life.c"
static Ppu ppu;
u8 reqdraw = 0;
static Device *devscreen;
void
nil_talk(Device *d, Uint8 b0, Uint8 w) {
(void)d;
(void)b0;
(void)w;
}
void
console_talk(Device *d, u8 b0, u8 w) {
if(!w) {
return;
}
switch(b0) {
case 0x8: txt_printf("%c", d->dat[0x8]); break;
case 0x9: txt_printf("0x%02x", d->dat[0x9]); break;
case 0xb: txt_printf("0x%04x", mempeek16(d->dat, 0xa)); break;
case 0xd: txt_printf("%s", &d->mem[mempeek16(d->dat, 0xc)]); break;
}
}
void
system_talk(Device *d, Uint8 b0, Uint8 w)
{
if(!w) {
d->dat[0x2] = d->u->wst.ptr;
d->dat[0x3] = d->u->rst.ptr;
} else {
putcolors(&ppu, &d->dat[0x8]);
reqdraw = 1;
}
(void)b0;
}
void
screen_talk(Device *d, Uint8 b0, Uint8 w) {
if(w && b0 == 0xe) {
Uint16 x = mempeek16(d->dat, 0x8);
Uint16 y = mempeek16(d->dat, 0xa);
Uint8 *addr = &d->mem[mempeek16(d->dat, 0xc)];
Uint8 *layer = d->dat[0xe] >> 4 & 0x1 ? ppu.fg : ppu.bg;
Uint8 mode = d->dat[0xe] >> 5;
if(!mode) {
putpixel(&ppu, layer, x, y, d->dat[0xe] & 0x3);
} else if(mode-- & 0x1) {
puticn(&ppu, layer, x, y, addr, d->dat[0xe] & 0xf, mode & 0x2, mode & 0x4);
} else {
putchr(&ppu, layer, x, y, addr, d->dat[0xe] & 0xf, mode & 0x2, mode & 0x4);
}
reqdraw = 1;
}
}
void
redraw(Uint16 *dst, Uxn *u) {
// TODO: The screen will flicker but using Mode4 for double buffering would
// be way too slow.
drawppu(&ppu);
clear_screen_m3();
// Copy ppu data to framebuffer.
for (size_t j = 0; j < ppu.height; ++j) {
for (size_t i = 0; i < ppu.width; ++i) {
FRAMEBUFFER[j][i] = ppu.output[i + j * ppu.width];
}
}
reqdraw = 0;
}
void
init_uxn(Uxn *u) {
// Initialize PPU.
initppu(&ppu, 30, 20, 0);
// Copy rom to VM.
memcpy(u->ram.dat + PAGE_PROGRAM, uxn_rom, sizeof(uxn_rom));
// Prepare devices.
portuxn(u, 0x0, "system", system_talk);
portuxn(u, 0x1, "console", console_talk);
devscreen = portuxn(u, 0x2, "screen", screen_talk);
portuxn(u, 0x3, "---", nil_talk);
portuxn(u, 0x4, "---", nil_talk);
portuxn(u, 0x5, "---", nil_talk);
portuxn(u, 0x6, "---", nil_talk);
portuxn(u, 0x7, "---", nil_talk);
portuxn(u, 0x8, "---", nil_talk);
portuxn(u, 0x9, "---", nil_talk);
portuxn(u, 0xa, "---", nil_talk);
portuxn(u, 0xb, "---", nil_talk);
portuxn(u, 0xc, "---", nil_talk);
portuxn(u, 0xd, "---", nil_talk);
portuxn(u, 0xe, "---", nil_talk);
portuxn(u, 0xf, "---", nil_talk);
mempoke16(devscreen->dat, 2, ppu.hor * 8);
mempoke16(devscreen->dat, 4, ppu.ver * 8);
}
int main(void) {
// Initialize display mode and bg palette.
DISP_CTRL = DISP_MODE_3 | DISP_BG_2;
// Initialize text engine.
txt_init_bitmap(
TXT_MODE_MODE3,
(Font){
.data = small_font,
.char_width = 4,
.char_height = 8,
.color = COLOR_BLUE,
.char_map = small_font_map,
});
// Register interrupts.
irq_init();
irs_set(IRQ_VBLANK, irs_stub);
// Initialize VM.
Uxn u = {0};
init_uxn(&u);
evaluxn(&u, 0x0100);
// Main loop.
int frame_counter = 0;
while(true) {
bios_vblank_wait();
poll_keys();
evaluxn(&u, mempeek16(devscreen->dat, 0));
if(reqdraw) {
redraw(ppu.output, &u);
}
frame_counter++;
};
return 0;
}
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