#include "fbotest.h"
#include <QApplication>
#include <QResizeEvent>
#include <QPaintEvent>

int main(int argc, char *argv[])
{
	QApplication a(argc, argv);
	GLWidget w;
	w.show();

	return a.exec();
}

GLWidget::GLWidget(QWidget *parent) :
	QGLWidget(QGLFormat(QGL::SampleBuffers), parent),
	source(0), multisampleBlit(0)
{
}

void GLWidget::resizeEvent(QResizeEvent *ev)
{
	makeCurrent();
	delete source;
	delete multisampleBlit;

	QGLFramebufferObjectFormat format;
	format.setAttachment(QGLFramebufferObject::NoAttachment);
	format.setSamples(4);
	format.setInternalTextureFormat(GL_RGBA16F);
	source = new QGLFramebufferObject(ev->size(), format);
	// random output:
	multisampleBlit = new QGLFramebufferObject(ev->size());
	// just black:
	// multisampleBlit = new QGLFramebufferObject(ev->size(), format);

	QRect rect(QPoint(0, 0), source->size());
	QPainter painter(source);
	painter.setCompositionMode(QPainter::CompositionMode_Source);
	painter.fillRect(rect, Qt::transparent);
	painter.setCompositionMode(QPainter::CompositionMode_SourceOver);

	painter.fillRect(0, 0, 100, 100, QColor(0, 127, 0, 127));
	painter.drawText(rect, Qt::AlignCenter, "Test");
}

void GLWidget::paintEvent(QPaintEvent *)
{
	makeCurrent();
	QPainter painter(this);
	painter.fillRect(rect(), QColor(255, 0, 255));

	if (!source)
		return;

	QGLFramebufferObject::blitFramebuffer(multisampleBlit,
										  rect(), source, rect());
	drawTexture(rect(), multisampleBlit->texture());
}