6502/8bitworkshop
1
0
Fork 0
mirror of https://github.com/sehugg/8bitworkshop.git synced 2024-08-26 00:29:05 +00:00
Code Issues Projects Releases Wiki Activity
2f7cf18d7c
8bitworkshop/gen/machine/chips/gtia.js

336 lines
10 KiB
JavaScript
Raw Blame History

"use strict";
// GTIA
// https://user.xmission.com/~trevin/atari/gtia_regs.html
// https://user.xmission.com/~trevin/atari/gtia_pinout.html
Object.defineProperty(exports, "__esModule", { value: true });
exports.GTIA = exports.CONSOL = exports.TRIG0 = void 0;
const emu_1 = require("../../common/emu");
const util_1 = require("../../common/util");
// write regs
const HPOSP0 = 0x0;
const HPOSM0 = 0x4;
const SIZEP0 = 0x8;
const SIZEM = 0x0c;
const GRAFP0 = 0x0d;
const GRAFM = 0x11;
const COLPM0 = 0x12;
const COLPF0 = 0x16;
const COLPF1 = 0x17;
const COLPF2 = 0x18;
const COLPF3 = 0x19;
const COLBK = 0x1a;
const PRIOR = 0x1b;
const VDELAY = 0x1c; // TODO
const GRACTL = 0x1d;
const HITCLR = 0x1e;
const CONSPK = 0x1f;
// read regs
const M0PF = 0x0;
const P0PF = 0x4;
const M0PL = 0x8;
const P0PL = 0xc;
exports.TRIG0 = 0x10;
exports.CONSOL = 0x1f;
const HOFFSET = -9; // bias to account for antic->gtia delay
const PRIOR_TABLE = [
0, 1, 2, 3, 7, 7, 7, 7, 8, 8, 8, 8, 4, 5, 6, 7,
0, 1, 2, 3, 7, 7, 7, 7, 8, 8, 8, 8, 4, 5, 6, 7,
0, 1, 6, 7, 5, 5, 5, 5, 8, 8, 8, 8, 2, 3, 4, 5,
0, 1, 6, 7, 5, 5, 5, 5, 8, 8, 8, 8, 2, 3, 4, 5,
4, 5, 6, 7, 3, 3, 3, 3, 8, 8, 8, 8, 0, 1, 2, 3,
4, 5, 6, 7, 3, 3, 3, 3, 8, 8, 8, 8, 0, 1, 2, 3,
4, 5, 6, 7, 3, 3, 3, 3, 8, 8, 8, 8, 0, 1, 2, 3,
4, 5, 6, 7, 3, 3, 3, 3, 8, 8, 8, 8, 0, 1, 2, 3,
2, 3, 4, 5, 7, 7, 7, 7, 8, 8, 8, 8, 0, 1, 6, 7,
2, 3, 4, 5, 7, 7, 7, 7, 8, 8, 8, 8, 0, 1, 6, 7,
2, 3, 4, 5, 7, 7, 7, 7, 8, 8, 8, 8, 0, 1, 6, 7,
2, 3, 4, 5, 7, 7, 7, 7, 8, 8, 8, 8, 0, 1, 6, 7,
2, 3, 4, 5, 7, 7, 7, 7, 8, 8, 8, 8, 0, 1, 6, 7,
2, 3, 4, 5, 7, 7, 7, 7, 8, 8, 8, 8, 0, 1, 6, 7,
2, 3, 4, 5, 7, 7, 7, 7, 8, 8, 8, 8, 0, 1, 6, 7,
2, 3, 4, 5, 7, 7, 7, 7, 8, 8, 8, 8, 0, 1, 6, 7, // 1000
];
const MODE_9_LOOKUP = [
COLPM0 + 0, COLPM0 + 1, COLPM0 + 2, COLPM0 + 3,
COLPF0 + 0, COLPF0 + 1, COLPF0 + 2, COLPF0 + 3,
COLBK, COLBK, COLBK, COLBK,
COLPF0 + 0, COLPF0 + 1, COLPF0 + 2, COLPF0 + 3,
];
class GTIA {
constructor() {
this.regs = new Uint8Array(0x20);
this.readregs = new Uint8Array(0x20);
this.shiftregs = new Uint32Array(8);
this.count = 0;
this.an = 0;
this.rgb = 0;
this.pmcol = 0;
this.gtiacol = 0;
this.gtiacol2 = 0;
this.hbias = HOFFSET;
this.pmDebugMask = -1;
}
reset() {
this.regs.fill(0);
this.readregs.fill(0); // TODO?
this.readregs[0x14] = 0xf; // NTSC
this.readregs.fill(0xf, 0x15); // default value for write-only regs
this.count = 0;
}
saveState() {
return (0, util_1.safe_extend)(0, {}, this);
}
loadState(s) {
(0, util_1.safe_extend)(0, this, s);
}
setReg(a, v) {
switch (a) {
case COLPM0:
case COLPM0 + 1:
case COLPM0 + 2:
case COLPM0 + 3:
case COLPF0:
case COLPF0 + 1:
case COLPF0 + 2:
case COLPF0 + 3:
case COLBK:
v &= 0xfe; // bit 0 unused in color regs
break;
case HITCLR:
this.readregs.fill(0, 0, 16);
return;
}
this.regs[a] = v;
}
readReg(a) {
switch (a) {
case exports.CONSOL:
return this.readregs[a] & ~this.regs[CONSPK];
}
return this.readregs[a];
}
sync() {
this.count = 0;
}
setBias(b) {
this.hbias = HOFFSET + b;
}
updateGfx(h, v, data) {
switch (h) {
case 0:
if (this.regs[GRACTL] & 1) {
// TODO: VDELAY
this.regs[GRAFM] = data;
}
break;
case 2:
case 3:
case 4:
case 5:
if (this.regs[GRACTL] & 2) {
if (!(v & 1) || !(this.regs[VDELAY] & (1 << (h + 2))))
this.regs[GRAFP0 - 2 + h] = data;
}
break;
}
}
getPlayfieldColor() {
// which GTIA mode?
switch (this.regs[PRIOR] >> 6) {
// normal mode
case 0:
switch (this.an) {
case 0:
return COLBK;
case 4:
case 5:
case 6:
case 7:
return COLPF0 + this.an - 4;
case 8:
// combine PF2 hue and PF1 luminance
return (this.regs[COLPF2] & 0xf0) | (this.regs[COLPF1] & 0x0f) | 0x100;
}
break;
// mode 9 -- 16 luminances
case 1:
return (this.regs[COLBK] & 0xf0) | (this.gtiacol & 0xf) | 0x100;
// mode 10 -- 9 colors from registers
case 2:
return MODE_9_LOOKUP[this.gtiacol];
// mode 11 -- 16 hues
case 3:
return (this.regs[COLBK] & 0xf) | (this.gtiacol << 4) | 0x100;
}
return 0x100; // black
}
anySpriteActive() {
return this.shiftregs[0] || this.shiftregs[1] || this.shiftregs[2]
|| this.shiftregs[3] || this.shiftregs[4] || this.shiftregs[5]
|| this.shiftregs[6] || this.shiftregs[7];
}
processPlayerMissile() {
// no p/m gfx, just evaluate horiz. triggers
if (!this.anySpriteActive()) {
this.evalTrigger(0);
this.evalTrigger(1);
this.evalTrigger(2);
this.evalTrigger(3);
this.evalTrigger(4);
this.evalTrigger(5);
this.evalTrigger(6);
this.evalTrigger(7);
this.pmcol = -1;
return;
}
// no collisions in blank area, but shift and trigger anyway
if (this.an == 2) {
this.shiftObject(0);
this.shiftObject(1);
this.shiftObject(2);
this.shiftObject(3);
this.shiftObject(4);
this.shiftObject(5);
this.shiftObject(6);
this.shiftObject(7);
this.pmcol = -1;
return;
}
// TODO: gtia, hi-res mode collisions
// compute gfx and collisions for players/missiles
let priobias = (this.regs[PRIOR] & 15) << 4; // TODO
let topprio = PRIOR_TABLE[(this.an & 7) + 8 + priobias];
let pfset = this.an - 4; // TODO?
let topobj = -1;
let ppmask = 0;
// players
for (let i = 0; i < 4; i++) {
let bit = this.shiftObject(i);
if (bit) {
if (pfset >= 0) { // TODO: hires and GTIA modes
this.readregs[P0PF + i] |= 1 << pfset;
}
ppmask |= 1 << i;
let prio = PRIOR_TABLE[i + priobias];
if (prio < topprio) {
topobj = i;
topprio = prio;
}
}
}
// missiles
for (let i = 0; i < 4; i++) {
let bit = this.shiftObject(i + 4);
if (bit) {
if (pfset >= 0) {
this.readregs[M0PF + i] |= 1 << pfset;
}
this.readregs[M0PL + i] |= ppmask;
let prio = (this.regs[PRIOR] & 0x10)
? PRIOR_TABLE[priobias + 15]
: PRIOR_TABLE[i + priobias];
if (prio < topprio) {
topobj = i + 4;
topprio = prio;
}
}
}
// set player-player collision flags
// TODO: either as a player or a GTIA mode 2 color
if (ppmask & 1)
this.readregs[P0PL + 0] |= ppmask & ~1;
if (ppmask & 2)
this.readregs[P0PL + 1] |= ppmask & ~2;
if (ppmask & 4)
this.readregs[P0PL + 2] |= ppmask & ~4;
if (ppmask & 8)
this.readregs[P0PL + 3] |= ppmask & ~8;
this.pmcol = topobj >= 0 ? this.getObjectColor(topobj) : -1;
}
shiftObject(i) {
let bit = (this.shiftregs[i] & 0x80000000) != 0;
this.shiftregs[i] <<= 1;
this.evalTrigger(i);
return bit;
}
getObjectColor(i) {
if ((this.regs[PRIOR] & 0x10) && i >= 4) {
return this.regs[COLPF3];
}
else {
return this.regs[COLPM0 + (i & 3)];
}
}
evalTrigger(i) {
if (this.regs[HPOSP0 + i] + this.hbias == this.count) {
this.triggerObject(i);
}
}
triggerObject(i) {
let size, data;
if (!(this.pmDebugMask & (1 << i)))
return;
if (i < 4) {
size = this.regs[SIZEP0 + i] & 3;
data = this.regs[GRAFP0 + i];
}
else {
let s = (i - 4) << 1;
size = (this.regs[SIZEM] >> s) & 3;
data = ((this.regs[GRAFM] >> s) & 3) << 6;
}
if (size & 1)
data = expandBits(data);
else
data <<= 8;
if (size == 3)
data = expandBits(data);
else
data <<= 16;
this.shiftregs[i] |= data;
}
clockPulse1() {
this.processPlayerMissile();
this.clockPulse2();
this.count++;
}
clockPulse2() {
var col;
if (this.pmcol >= 0) {
col = this.pmcol;
}
else {
let pf = this.getPlayfieldColor();
col = pf & 0x100 ? pf & 0xff : this.regs[pf];
}
this.rgb = COLORS_RGBA[col];
// TODO: hires modes return 8, so other modes wont work
this.gtiacol2 = (this.gtiacol2 << 1) | (this.an >> 3);
}
clockPulse4() {
// latch GTIA buffer
this.gtiacol = this.gtiacol2 & 15;
}
static stateToLongString(state) {
let s = '';
s += `X: ${(0, util_1.lpad)(state.count, 3)} ANTIC: ${(0, util_1.hex)(state.an, 1)} PM: ${(0, util_1.hex)(state.pmcol, 3)}\n`;
s += "Write Registers:\n";
s += (0, emu_1.dumpRAM)(state.regs, 0, 32);
s += "Read Registers:\n";
s += (0, emu_1.dumpRAM)(state.readregs, 0, 32);
return s;
}
}
exports.GTIA = GTIA;
function expandBits(x) {
x = (x | (x << 8)) & 0x00FF00FF;
x = (x | (x << 4)) & 0x0F0F0F0F;
x = (x | (x << 2)) & 0x33333333;
x = (x | (x << 1)) & 0x55555555;
return x | (x << 1);
}
var COLORS_RGBA = new Uint32Array(256);
for (var i = 0; i < 256; i++) {
COLORS_RGBA[i] = (0, emu_1.gtia_ntsc_to_rgb)(i);
}
//# sourceMappingURL=gtia.js.map
Reference in New Issue View Git Blame Copy Permalink