all repos — mgba @ d831de205fe45a9458efa4015bc0ef808ae84925

mGBA Game Boy Advance Emulator

src/core/timing.c (view raw)

 1/* Copyright (c) 2013-2016 Jeffrey Pfau
 2 *
 3 * This Source Code Form is subject to the terms of the Mozilla Public
 4 * License, v. 2.0. If a copy of the MPL was not distributed with this
 5 * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
 6#include "timing.h"
 7
 8DEFINE_VECTOR(mTimingEventList, struct mTimingEvent*);
 9
10void mTimingInit(struct mTiming* timing) {
11	mTimingEventListInit(&timing->events, 0);
12	timing->masterCycles = 0;
13}
14
15void mTimingDeinit(struct mTiming* timing) {
16	mTimingEventListDeinit(&timing->events);
17}
18
19void mTimingClear(struct mTiming* timing) {
20	mTimingEventListClear(&timing->events);
21	timing->masterCycles = 0;
22}
23
24void mTimingSchedule(struct mTiming* timing, struct mTimingEvent* event, int32_t when) {
25	event->when = when + timing->masterCycles;
26	size_t e;
27	for (e = 0; e < mTimingEventListSize(&timing->events); ++e) {
28		struct mTimingEvent* next = *mTimingEventListGetPointer(&timing->events, e);
29		int32_t nextWhen = next->when - timing->masterCycles;
30		if (nextWhen > when) {
31			mTimingEventListUnshift(&timing->events, e, 1);
32			*mTimingEventListGetPointer(&timing->events, e) = event;
33			return;
34		}
35	}
36	*mTimingEventListAppend(&timing->events) = event;
37}
38
39void mTimingTick(struct mTiming* timing, int32_t cycles) {
40	timing->masterCycles += cycles;
41	while (mTimingEventListSize(&timing->events)) {
42		struct mTimingEvent* next = *mTimingEventListGetPointer(&timing->events, 0);
43		int32_t nextWhen = next->when - timing->masterCycles;
44		if (nextWhen > 0) {
45			return;
46		}
47		mTimingEventListShift(&timing->events, 0, 1);
48		next->callback(timing, next->context, -nextWhen);
49	}
50}
51
52int32_t mTimingNextEvent(struct mTiming* timing) {
53	if (!mTimingEventListSize(&timing->events)) {
54		return INT_MAX;
55	}
56	struct mTimingEvent* next = *mTimingEventListGetPointer(&timing->events, 0);
57	return next->when - timing->masterCycles;
58}