C++ QOpenGLFunctions_2_1::glVertex2f方法代码示例

//override draw function
void ccMouseCircle::draw(CC_DRAW_CONTEXT& context)
{
	//only draw when visible
	if (!ccMouseCircle::isVisible())
		return;

	//only draw in 2D foreground mode
	if (!MACRO_Foreground(context) || !MACRO_Draw2D(context))
		return;

	//get the set of OpenGL functions (version 2.1)
	QOpenGLFunctions_2_1 *glFunc = context.glFunctions<QOpenGLFunctions_2_1>();
	assert(glFunc != nullptr);

	if (glFunc == nullptr)
		return;

	//test viewport parameters
	const ccViewportParameters& params = context.display->getViewportParameters();
	glFunc->glPushAttrib(GL_LINE_BIT);

	float relativeZoom = 1.0f;
	float dx = 0.0f;
	float dy = 0.0f;
	if (!m_params.perspectiveView) //ortho mode
	{
		//Screen pan & pivot compensation
		float totalZoom = m_params.zoom / m_params.pixelSize;
		m_winTotalZoom = params.zoom / params.pixelSize;
		relativeZoom = m_winTotalZoom / totalZoom;

		CCVector3d dC = m_params.cameraCenter - params.cameraCenter;
		
		CCVector3d P = m_params.pivotPoint - params.pivotPoint;
		m_params.viewMat.apply(P);

		static_cast<float>(dC.x + P.x);
		static_cast<float>(dC.y + P.y);

		dx *= m_winTotalZoom;
		dy *= m_winTotalZoom;
	}

	//thick dotted line
	glFunc->glLineWidth(2);
	glFunc->glLineStipple(1, 0xAAAA);
	glFunc->glEnable(GL_LINE_STIPPLE);

	const unsigned char* defaultColor = m_selected ? ccColor::red.rgba : context.textDefaultCol.rgb;
	glFunc->glColor3ubv(ccColor::red.rgba);

	//get height & width
	int halfW = static_cast<int>(context.glW / 2.0f);
	int halfH = static_cast<int>(context.glH / 2.0f);
	
	//get mouse position
	QPoint p = m_owner->asWidget()->mapFromGlobal(QCursor::pos());
	int mx = p.x(); //mouse x-coord
	int my = 2*halfH - p.y(); //mouse y-coord in OpenGL coordinates (origin at bottom left, not top left)
	
	//calculate circle location
	int cx = dx+mx-halfW;
	int cy = dy+my-halfH;

	//draw circle
	glFunc->glBegin(GL_LINE_LOOP);
	for (int n = 0; n < ccMouseCircle::RESOLUTION; n++)
	{
		glFunc->glVertex2f(ccMouseCircle::UNIT_CIRCLE[n][0] * ccMouseCircle::RADIUS + cx, ccMouseCircle::UNIT_CIRCLE[n][1] * ccMouseCircle::RADIUS + cy);
	}
	glFunc->glEnd();
	glFunc->glPopAttrib();
}

void cc2DViewportLabel::drawMeOnly(CC_DRAW_CONTEXT& context)
{
	//2D foreground only
	if (!MACRO_Foreground(context) || !MACRO_Draw2D(context))
		return;
	
	//get the set of OpenGL functions (version 2.1)
	QOpenGLFunctions_2_1 *glFunc = context.glFunctions<QOpenGLFunctions_2_1>();
	assert( glFunc != nullptr );
	
	if ( glFunc == nullptr )
		return;
	
	//test viewport parameters
	const ccViewportParameters& params = context.display->getViewportParameters();

	//general parameters
	if (	params.perspectiveView != m_params.perspectiveView
		||	params.objectCenteredView != m_params.objectCenteredView
		||	params.pixelSize != m_params.pixelSize)
	{
			return;
	}

	//test base view matrix
	for (unsigned i = 0; i < 12; ++i)
		if (fabs(params.viewMat.data()[i] - m_params.viewMat.data()[i]) > ZERO_TOLERANCE)
			return;

	if (m_params.perspectiveView)
	{
		if (params.fov != m_params.fov || params.perspectiveAspectRatio != m_params.perspectiveAspectRatio)
			return;

		if ((params.pivotPoint - m_params.pivotPoint).norm() > ZERO_TOLERANCE
			|| (params.cameraCenter - m_params.cameraCenter).norm() > ZERO_TOLERANCE)
			return;
	}
	else
	{
		if (params.orthoAspectRatio != m_params.orthoAspectRatio)
			return;
	}

	glFunc->glPushAttrib(GL_LINE_BIT);

	float relativeZoom = 1.0f;
	float dx = 0, dy = 0;
	if (!m_params.perspectiveView) //ortho mode
	{
		//Screen pan & pivot compensation
		float totalZoom = m_params.zoom / m_params.pixelSize;
		float winTotalZoom = params.zoom / params.pixelSize;
		relativeZoom = winTotalZoom / totalZoom;

		CCVector3d dC = m_params.cameraCenter - params.cameraCenter;

		CCVector3d P = m_params.pivotPoint - params.pivotPoint;
		m_params.viewMat.apply(P);

		dx = static_cast<float>(dC.x + P.x);
		dy = static_cast<float>(dC.y + P.y);

		dx *= winTotalZoom;
		dy *= winTotalZoom;
	}

	//thick dotted line
	glFunc->glLineWidth(2);
	glFunc->glLineStipple(1, 0xAAAA);
	glFunc->glEnable(GL_LINE_STIPPLE);

	const unsigned char* defaultColor = m_selected ? ccColor::red.rgba : context.textDefaultCol.rgb;
	glFunc->glColor3ubv(defaultColor);

	glFunc->glBegin(GL_LINE_LOOP);
	glFunc->glVertex2f(dx + m_roi[0] * relativeZoom, dy + m_roi[1] * relativeZoom);
	glFunc->glVertex2f(dx + m_roi[2] * relativeZoom, dy + m_roi[1] * relativeZoom);
	glFunc->glVertex2f(dx + m_roi[2] * relativeZoom, dy + m_roi[3] * relativeZoom);
	glFunc->glVertex2f(dx + m_roi[0] * relativeZoom, dy + m_roi[3] * relativeZoom);
	glFunc->glEnd();

	glFunc->glPopAttrib();

	//title
	QString title(getName());
	if (!title.isEmpty())
	{
		QFont titleFont(context.display->getTextDisplayFont()); //takes rendering zoom into account!
		titleFont.setBold(true);
		QFontMetrics titleFontMetrics(titleFont);
		int titleHeight = titleFontMetrics.height();

		int xStart = (int)(dx + 0.5f*(float)context.glW + std::min<float>(m_roi[0], m_roi[2])*relativeZoom);
		int yStart = (int)(dy + 0.5f*(float)context.glH + std::min<float>(m_roi[1], m_roi[3])*relativeZoom);

		context.display->displayText(title, xStart, yStart - 5 - titleHeight, ccGenericGLDisplay::ALIGN_DEFAULT, 0, defaultColor, &titleFont);
	}
}