1/* Copyright (c) 2013-2014 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 "Display.h"
  7
  8#include <QApplication>
  9#include <QResizeEvent>
 10
 11extern "C" {
 12#include "gba-thread.h"
 13}
 14
 15using namespace QGBA;
 16
 17static const GLint _glVertices[] = {
 18	0, 0,
 19	256, 0,
 20	256, 256,
 21	0, 256
 22};
 23
 24static const GLint _glTexCoords[] = {
 25	0, 0,
 26	1, 0,
 27	1, 1,
 28	0, 1
 29};
 30
 31Display::Display(QGLFormat format, QWidget* parent)
 32	: QGLWidget(format, parent)
 33	, m_painter(nullptr)
 34	, m_drawThread(nullptr)
 35{
 36	setSizePolicy(QSizePolicy::MinimumExpanding, QSizePolicy::MinimumExpanding);
 37	setMinimumSize(VIDEO_HORIZONTAL_PIXELS, VIDEO_VERTICAL_PIXELS);
 38	setAutoBufferSwap(false);
 39	setCursor(Qt::BlankCursor);
 40}
 41
 42void Display::startDrawing(const uint32_t* buffer, GBAThread* thread) {
 43	if (m_drawThread) {
 44		return;
 45	}
 46	m_drawThread = new QThread(this);
 47	m_painter = new Painter(this);
 48	m_painter->setContext(thread);
 49	m_painter->setBacking(buffer);
 50	m_painter->moveToThread(m_drawThread);
 51	m_context = thread;
 52	doneCurrent();
 53	context()->moveToThread(m_drawThread);
 54	connect(m_drawThread, SIGNAL(started()), m_painter, SLOT(start()));
 55	m_drawThread->start(QThread::TimeCriticalPriority);
 56}
 57
 58void Display::stopDrawing() {
 59	if (m_drawThread) {
 60		if (GBAThreadIsActive(m_context)) {
 61			GBAThreadInterrupt(m_context);
 62			GBASyncSuspendDrawing(&m_context->sync);
 63		}
 64		QMetaObject::invokeMethod(m_painter, "stop", Qt::BlockingQueuedConnection);
 65		m_drawThread->exit();
 66		m_drawThread = nullptr;
 67		if (GBAThreadIsActive(m_context)) {
 68			GBASyncResumeDrawing(&m_context->sync);
 69			GBAThreadContinue(m_context);
 70		}
 71	}
 72}
 73
 74void Display::pauseDrawing() {
 75	if (m_drawThread) {
 76		if (GBAThreadIsActive(m_context)) {
 77			GBAThreadInterrupt(m_context);
 78			GBASyncSuspendDrawing(&m_context->sync);
 79		}
 80		QMetaObject::invokeMethod(m_painter, "pause", Qt::BlockingQueuedConnection);
 81		if (GBAThreadIsActive(m_context)) {
 82			GBASyncResumeDrawing(&m_context->sync);
 83			GBAThreadContinue(m_context);
 84		}
 85	}
 86}
 87
 88void Display::unpauseDrawing() {
 89	if (m_drawThread) {
 90		if (GBAThreadIsActive(m_context)) {
 91			GBAThreadInterrupt(m_context);
 92			GBASyncSuspendDrawing(&m_context->sync);
 93		}
 94		QMetaObject::invokeMethod(m_painter, "unpause", Qt::BlockingQueuedConnection);
 95		if (GBAThreadIsActive(m_context)) {
 96			GBASyncResumeDrawing(&m_context->sync);
 97			GBAThreadContinue(m_context);
 98		}
 99	}
100}
101
102void Display::forceDraw() {
103	if (m_drawThread) {
104		QMetaObject::invokeMethod(m_painter, "forceDraw", Qt::QueuedConnection);
105	}
106}
107
108#ifdef USE_PNG
109void Display::screenshot() {
110	GBAThreadInterrupt(m_context);
111	GBAThreadTakeScreenshot(m_context);
112	GBAThreadContinue(m_context);
113}
114#endif
115
116void Display::initializeGL() {
117	glClearColor(0, 0, 0, 0);
118	glClear(GL_COLOR_BUFFER_BIT);
119	swapBuffers();
120}
121
122void Display::resizeEvent(QResizeEvent* event) {
123	if (m_drawThread) {
124		GBAThreadInterrupt(m_context);
125		GBASyncSuspendDrawing(&m_context->sync);
126		QMetaObject::invokeMethod(m_painter, "resize", Qt::BlockingQueuedConnection, Q_ARG(QSize, event->size()));
127		GBASyncResumeDrawing(&m_context->sync);
128		GBAThreadContinue(m_context);
129	}
130}
131
132Painter::Painter(Display* parent)
133	: m_gl(parent)
134{
135	m_size = parent->size();
136}
137
138void Painter::setContext(GBAThread* context) {
139	m_context = context;
140}
141
142void Painter::setBacking(const uint32_t* backing) {
143	m_backing = backing;
144}
145
146void Painter::resize(const QSize& size) {
147	m_size = size;
148	m_gl->makeCurrent();
149	glViewport(0, 0, m_size.width() * m_gl->devicePixelRatio(), m_size.height() * m_gl->devicePixelRatio());
150	glDrawArrays(GL_TRIANGLE_FAN, 0, 4);
151	m_gl->swapBuffers();
152	m_gl->doneCurrent();
153}
154
155void Painter::start() {
156	m_gl->makeCurrent();
157	glEnable(GL_TEXTURE_2D);
158	glGenTextures(1, &m_tex);
159	glBindTexture(GL_TEXTURE_2D, m_tex);
160	glTexEnvf(GL_TEXTURE_ENV, GL_TEXTURE_ENV_MODE, GL_REPLACE);
161	glTexParameterf(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR);
162	glTexParameterf(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_NEAREST);
163	glEnableClientState(GL_TEXTURE_COORD_ARRAY);
164	glEnableClientState(GL_VERTEX_ARRAY);
165	glVertexPointer(2, GL_INT, 0, _glVertices);
166	glTexCoordPointer(2, GL_INT, 0, _glTexCoords);
167	glMatrixMode(GL_PROJECTION);
168	glLoadIdentity();
169	glOrtho(0, 240, 160, 0, 0, 1);
170	glMatrixMode(GL_MODELVIEW);
171	glLoadIdentity();
172	m_gl->doneCurrent();
173
174	m_drawTimer = new QTimer;
175	m_drawTimer->moveToThread(QThread::currentThread());
176	m_drawTimer->setInterval(0);
177	connect(m_drawTimer, SIGNAL(timeout()), this, SLOT(draw()));
178	m_drawTimer->start();
179}
180
181void Painter::draw() {
182	m_gl->makeCurrent();
183	if (GBASyncWaitFrameStart(&m_context->sync, m_context->frameskip)) {
184		glViewport(0, 0, m_size.width() * m_gl->devicePixelRatio(), m_size.height() * m_gl->devicePixelRatio());
185		glTexImage2D(GL_TEXTURE_2D, 0, GL_RGBA, 256, 256, 0, GL_RGBA, GL_UNSIGNED_BYTE, m_backing);
186		glDrawArrays(GL_TRIANGLE_FAN, 0, 4);
187		if (m_context->sync.videoFrameWait) {
188			glFlush();
189		}
190	}
191	GBASyncWaitFrameEnd(&m_context->sync);
192	m_gl->swapBuffers();
193	m_gl->doneCurrent();
194}
195
196void Painter::forceDraw() {
197	m_gl->makeCurrent();
198	glViewport(0, 0, m_size.width() * m_gl->devicePixelRatio(), m_size.height() * m_gl->devicePixelRatio());
199	glTexImage2D(GL_TEXTURE_2D, 0, GL_RGBA, 256, 256, 0, GL_RGBA, GL_UNSIGNED_BYTE, m_backing);
200	glDrawArrays(GL_TRIANGLE_FAN, 0, 4);
201	if (m_context->sync.videoFrameWait) {
202		glFlush();
203	}
204	m_gl->swapBuffers();
205	m_gl->doneCurrent();
206}
207
208void Painter::stop() {
209	m_drawTimer->stop();
210	delete m_drawTimer;
211	m_gl->makeCurrent();
212	glDeleteTextures(1, &m_tex);
213	glClear(GL_COLOR_BUFFER_BIT);
214	m_gl->swapBuffers();
215	m_gl->doneCurrent();
216	m_gl->context()->moveToThread(QApplication::instance()->thread());
217}
218
219void Painter::pause() {
220	m_drawTimer->stop();
221	// Make sure both buffers are filled
222	forceDraw();
223	forceDraw();
224}
225
226void Painter::unpause() {
227	m_drawTimer->start();
228}