C++ QOpenGLShaderProgram::release方法代码示例

	template <typename R> void call(R *r) {
		const auto &view = r->getViewMatrix();
		const auto &projection = r->getProjectionMatrix();
		for (auto &con : r->getScenario().getWorld().cellCellConnections) {
			auto &cc = *(con.second.get());
			if (cc.adhCoef > 0) {
				shader.bind();
				cube.vao.bind();
				QColor color = QColor::fromHsvF(cc.adhCoef * 0.45, 0.7, 0.7);
				shader.setUniformValue(shader.uniformLocation("color"), color);
				shader.setUniformValue(shader.uniformLocation("projection"), projection);
				shader.setUniformValue(shader.uniformLocation("view"), view);
				QMatrix4x4 model;
				auto ab = toQV3D(cc.cells.second->getPosition() - cc.cells.first->getPosition());
				model.translate(toQV3D(cc.cells.second->getPosition()) - ab * 0.5);
				auto dp = ab.normalized().x();
				if (dp != 1 && dp != -1) {
					model.rotate(acos(dp) * 180.0 / M_PI,
					             QVector3D::crossProduct(QVector3D(1, 0, 0), ab));
					model.scale(ab.length() * 0.5, 1.0, 1.0);
					QMatrix4x4 nmatrix = (model).inverted().transposed();
					shader.setUniformValue(shader.uniformLocation("model"), model);
					shader.setUniformValue(shader.uniformLocation("normalMatrix"), nmatrix);
					GL->glDrawElements(GL_TRIANGLES, cube.indices.size(), GL_UNSIGNED_INT, 0);
				}
				cube.vao.release();
				shader.release();
			}
		}
	}

	template <typename R> void call(R *r) {
		const auto &view = r->getViewMatrix();
		const auto &projection = r->getProjectionMatrix();
		shader.bind();
		sphere.vao.bind();
		texture->bind(0);
		shader.setUniformValue(shader.uniformLocation("projection"), projection);
		shader.setUniformValue(shader.uniformLocation("view"), view);
		for (auto &n : r->getScenario().nutrientSources) {
			QMatrix4x4 model;
			model.translate(n.pos.x(), n.pos.y(), n.pos.z());
			double c = n.content / n.initialcontent;
			double l = 15.0 + sqrt(n.sqradius * c) * 0.05;
			model.scale(l, l, l);
			QMatrix4x4 nmatrix = (model).inverted().transposed();
			shader.setUniformValue(shader.uniformLocation("model"), model);
			shader.setUniformValue(shader.uniformLocation("normalMatrix"), nmatrix);
			auto hsv = QColor::fromHsvF(c * 0.35, 0.9, 0.9);
			QVector4D col(hsv.redF(), hsv.greenF(), hsv.blueF(), 0.5);
			std::cerr << "c = " << c << ", r = " << col.x() << std::endl;
			shader.setUniformValue(shader.uniformLocation("color"), col);
			GL->glDrawElements(GL_TRIANGLES, sphere.indices.size(), GL_UNSIGNED_INT, 0);
		}
		sphere.vao.release();
		shader.release();
	}

void
Scene_polylines_item::initializeBuffers(CGAL::Three::Viewer_interface *viewer = 0) const
{
    QOpenGLShaderProgram *program;
   //vao for the lines
    {
        program = getShaderProgram(PROGRAM_NO_SELECTION, viewer);
        program->bind();

        vaos[Edges]->bind();
        buffers[Edges_Vertices].bind();
        buffers[Edges_Vertices].allocate(positions_lines.data(),
                            static_cast<int>(positions_lines.size()*sizeof(float)));
        program->enableAttributeArray("vertex");
        program->setAttributeBuffer("vertex",GL_FLOAT,0,4);
        buffers[Edges_Vertices].release();
        vaos[Edges]->release();
        program->release();

        nb_lines = positions_lines.size();
        positions_lines.clear();
        positions_lines.swap(positions_lines);
    }
   are_buffers_filled = true;
}

void Painter::paint_3_2_label(
    const QMatrix4x4 & viewProjection
,   float timef)
{
    QOpenGLShaderProgram * program;

    glEnable(GL_BLEND);
    glBlendFunc(GL_SRC_ALPHA, GL_ONE_MINUS_SRC_ALPHA);

    glActiveTexture(GL_TEXTURE0);

    program = m_programs[LabelDistanceMapProgram];
    program->bind();

    glBindTexture(GL_TEXTURE_2D, m_hpicgsLabelDM);
    program->setUniformValue("mvp", viewProjection * m_transforms[0]);
    m_hpicgsLabel->draw(*this);

    glBindTexture(GL_TEXTURE_2D, m_portccLabelDM);
    program->setUniformValue("mvp", viewProjection * m_transforms[1]);
    m_portccLabel->draw(*this);

    program->release();

    glBindTexture(GL_TEXTURE_2D, 0);
    glDisable(GL_BLEND);
}

void
Scene_polylines_item_private::initializeBuffers(CGAL::Three::Viewer_interface *viewer = 0) const
{
  float lineWidth[2];
  viewer->glGetFloatv(GL_LINE_WIDTH_RANGE, lineWidth);
  line_Slider->setMaximum(lineWidth[1]);
    QOpenGLShaderProgram *program;
   //vao for the lines
    {
        program = item->getShaderProgram(Scene_polylines_item::PROGRAM_NO_SELECTION, viewer);
        program->bind();

        item->vaos[Edges]->bind();
        item->buffers[Edges_Vertices].bind();
        item->buffers[Edges_Vertices].allocate(positions_lines.data(),
                            static_cast<int>(positions_lines.size()*sizeof(float)));
        program->enableAttributeArray("vertex");
        program->setAttributeBuffer("vertex",GL_FLOAT,0,4);
        item->buffers[Edges_Vertices].release();
        item->vaos[Edges]->release();
        program->release();

        nb_lines = positions_lines.size();
        positions_lines.clear();
        positions_lines.swap(positions_lines);
    }
    item->are_buffers_filled = true;
}

	template <typename R> void call(R *r) {
		using V = decltype(declval<typename R::Cell>().getPosition());
		const auto &view = r->getViewMatrix();
		const auto &projection = r->getProjectionMatrix();
		shader.bind();
		disk.vao.bind();
		QVector4D color(0.9f, 0.9f, 0.05f, 1.0f);
		shader.setUniformValue(shader.uniformLocation("color"), color);
		shader.setUniformValue(shader.uniformLocation("projection"), projection);
		shader.setUniformValue(shader.uniformLocation("view"), view);
		for (auto &con : r->getScenario().getWorld().cellCellConnections) {
			auto &cc = con.second;
			QMatrix4x4 model;
			model.translate(
			    toQV3D(cc.cells.first->getPosition() + cc.normal * cc.midpoint.first));
			auto rot = V::getRotation(V(0, 0, 1), cc.normal);
			model.rotate(rot.teta * 180.0 / M_PI, toQV3D(rot.n));
			float rad = static_cast<float>(sqrt(cc.sqradius));
			model.scale(rad, rad, rad);
			QMatrix4x4 nmatrix = (model).inverted().transposed();
			shader.setUniformValue(shader.uniformLocation("model"), model);
			shader.setUniformValue(shader.uniformLocation("normalMatrix"), nmatrix);
			GL->glDrawElements(GL_TRIANGLES, disk.indices.size(), GL_UNSIGNED_INT, 0);
		}
		color = QVector4D(0.1f, 0.7f, 0.f, 1.0f);
		shader.setUniformValue(shader.uniformLocation("color"), color);
		for (auto &con : r->getScenario().getWorld().cellCellConnections) {
			auto &cc = con.second;
			QMatrix4x4 model;
			model.translate(toQV3D(cc.cells.first->getPosition() +
			                       cc.icb.first.currentBasis.X * cc.midpoint.first));
			auto rot = V::getRotation(V(0, 0, 1), cc.icb.first.currentBasis.X);
			model.rotate(rot.teta * 180.0 / M_PI, toQV3D(rot.n));
			float rad = static_cast<float>(sqrt(cc.sqradius));
			model.scale(rad, rad, rad);
			QMatrix4x4 nmatrix = (model).inverted().transposed();
			shader.setUniformValue(shader.uniformLocation("model"), model);
			shader.setUniformValue(shader.uniformLocation("normalMatrix"), nmatrix);
			GL->glDrawElements(GL_TRIANGLES, disk.indices.size(), GL_UNSIGNED_INT, 0);
		}
		color = QVector4D(0.f, 0.1f, 0.7f, 1.0f);
		shader.setUniformValue(shader.uniformLocation("color"), color);
		for (auto &con : r->getScenario().getWorld().cellCellConnections) {
			auto &cc = con.second;
			QMatrix4x4 model;
			model.translate(toQV3D(cc.cells.second->getPosition() +
			                       cc.icb.second.currentBasis.X * cc.midpoint.second));
			auto rot = V::getRotation(V(0, 0, 1), cc.icb.second.currentBasis.X);
			model.rotate(rot.teta * 180.0 / M_PI, toQV3D(rot.n));
			float rad = static_cast<float>(sqrt(cc.sqradius));
			model.scale(rad, rad, rad);
			QMatrix4x4 nmatrix = (model).inverted().transposed();
			shader.setUniformValue(shader.uniformLocation("model"), model);
			shader.setUniformValue(shader.uniformLocation("normalMatrix"), nmatrix);
			GL->glDrawElements(GL_TRIANGLES, disk.indices.size(), GL_UNSIGNED_INT, 0);
		}
		disk.vao.release();
		shader.release();
	}

/******************************************************************************
* Renders a 2d polyline in the viewport.
******************************************************************************/
void ViewportSceneRenderer::render2DPolyline(const Point2* points, int count, const ColorA& color, bool closed)
{
	OVITO_STATIC_ASSERT(sizeof(points[0]) == 2*sizeof(GLfloat));

	// Load OpenGL shader.
	QOpenGLShaderProgram* shader = loadShaderProgram("line", ":/core/glsl/lines/line.vs", ":/core/glsl/lines/line.fs");
	if(!shader->bind())
		throw Exception(tr("Failed to bind OpenGL shader."));

	bool wasDepthTestEnabled = glIsEnabled(GL_DEPTH_TEST);
	glDisable(GL_DEPTH_TEST);

	GLint vc[4];
	glGetIntegerv(GL_VIEWPORT, vc);
	QMatrix4x4 tm;
	tm.ortho(vc[0], vc[0] + vc[2], vc[1] + vc[3], vc[1], -1, 1);
	OVITO_CHECK_OPENGL(shader->setUniformValue("modelview_projection_matrix", tm));

	QOpenGLBuffer vertexBuffer;
	if(glformat().majorVersion() >= 3) {
		if(!vertexBuffer.create())
			throw Exception(tr("Failed to create OpenGL vertex buffer."));
		if(!vertexBuffer.bind())
				throw Exception(tr("Failed to bind OpenGL vertex buffer."));
		vertexBuffer.allocate(points, 2 * sizeof(GLfloat) * count);
		OVITO_CHECK_OPENGL(shader->enableAttributeArray("position"));
		OVITO_CHECK_OPENGL(shader->setAttributeBuffer("position", GL_FLOAT, 0, 2));
		vertexBuffer.release();
	}
	else {
		OVITO_CHECK_OPENGL(glEnableClientState(GL_VERTEX_ARRAY));
		OVITO_CHECK_OPENGL(glVertexPointer(2, GL_FLOAT, 0, points));
	}

	if(glformat().majorVersion() >= 3) {
		OVITO_CHECK_OPENGL(shader->disableAttributeArray("color"));
		OVITO_CHECK_OPENGL(shader->setAttributeValue("color", color.r(), color.g(), color.b(), color.a()));
	}
	else {
		OVITO_CHECK_OPENGL(glColor4(color));
	}

	OVITO_CHECK_OPENGL(glDrawArrays(closed ? GL_LINE_LOOP : GL_LINE_STRIP, 0, count));

	if(glformat().majorVersion() >= 3) {
		shader->disableAttributeArray("position");
	}
	else {
		OVITO_CHECK_OPENGL(glDisableClientState(GL_VERTEX_ARRAY));
	}
	shader->release();
	if(wasDepthTestEnabled) glEnable(GL_DEPTH_TEST);
}

/******************************************************************************
* Renders the geometry as triangle mesh with normals.
******************************************************************************/
void OpenGLArrowPrimitive::renderWithNormals(ViewportSceneRenderer* renderer)
{
	QOpenGLShaderProgram* shader = renderer->isPicking() ? _pickingShader : _shader;
	if(!shader->bind())
		throw Exception(QStringLiteral("Failed to bind OpenGL shader."));

	glEnable(GL_CULL_FACE);
	glCullFace(GL_BACK);

	shader->setUniformValue("modelview_projection_matrix", (QMatrix4x4)(renderer->projParams().projectionMatrix * renderer->modelViewTM()));
	if(!renderer->isPicking())
		shader->setUniformValue("normal_matrix", (QMatrix3x3)(renderer->modelViewTM().linear().inverse().transposed()));

	GLint pickingBaseID;
	if(renderer->isPicking()) {
		pickingBaseID = renderer->registerSubObjectIDs(elementCount());
		renderer->activateVertexIDs(shader, _chunkSize * _verticesPerElement, true);
	}

	for(int chunkIndex = 0; chunkIndex < _verticesWithNormals.size(); chunkIndex++, pickingBaseID += _chunkSize) {
		int chunkStart = chunkIndex * _chunkSize;
		int chunkSize = std::min(_elementCount - chunkStart, _chunkSize);

		if(renderer->isPicking())
			shader->setUniformValue("pickingBaseID", pickingBaseID);

		_verticesWithNormals[chunkIndex].bindPositions(renderer, shader, offsetof(VertexWithNormal, pos));
		if(!renderer->isPicking()) {
			_verticesWithNormals[chunkIndex].bindNormals(renderer, shader, offsetof(VertexWithNormal, normal));
			_verticesWithNormals[chunkIndex].bindColors(renderer, shader, 4, offsetof(VertexWithNormal, color));
		}

		int stripPrimitivesPerElement = _stripPrimitiveVertexCounts.size() / _chunkSize;
		int stripVerticesPerElement = std::accumulate(_stripPrimitiveVertexCounts.begin(), _stripPrimitiveVertexCounts.begin() + stripPrimitivesPerElement, 0);
		OVITO_CHECK_OPENGL(shader->setUniformValue("verticesPerElement", (GLint)stripVerticesPerElement));
		OVITO_CHECK_OPENGL(renderer->glMultiDrawArrays(GL_TRIANGLE_STRIP, _stripPrimitiveVertexStarts.data(), _stripPrimitiveVertexCounts.data(), stripPrimitivesPerElement * chunkSize));

		int fanPrimitivesPerElement = _fanPrimitiveVertexCounts.size() / _chunkSize;
		int fanVerticesPerElement = std::accumulate(_fanPrimitiveVertexCounts.begin(), _fanPrimitiveVertexCounts.begin() + fanPrimitivesPerElement, 0);
		OVITO_CHECK_OPENGL(shader->setUniformValue("verticesPerElement", (GLint)fanVerticesPerElement));
		OVITO_CHECK_OPENGL(renderer->glMultiDrawArrays(GL_TRIANGLE_FAN, _fanPrimitiveVertexStarts.data(), _fanPrimitiveVertexCounts.data(), fanPrimitivesPerElement * chunkSize));

		_verticesWithNormals[chunkIndex].detachPositions(renderer, shader);
		if(!renderer->isPicking()) {
			_verticesWithNormals[chunkIndex].detachNormals(renderer, shader);
			_verticesWithNormals[chunkIndex].detachColors(renderer, shader);
		}
	}
	if(renderer->isPicking())
		renderer->deactivateVertexIDs(shader, true);

	shader->release();
}

    void useShader(QOpenGLShaderProgram& _s,
                   std::function<void(UniformHandler&)>f) {
      withCurrentContext([&](QOpenGLFunctions& _gl) {
        _s.bind();
        {
          UniformHandler _handler(_gl, _s);
          f(_handler);

          // Destructor of handler is called here implicitly
          // by RAII to unbind all textures
        }
        _s.release();
      });
    }

void AssimpScene::draw(
    OpenGLFunctions & gl
,   QOpenGLShaderProgram & program
,   const GLenum mode)
{
    if (!m_valid)
        return;

    if (!program.isLinked())
        return;

    std::vector<AssimpMesh *>::const_iterator i = m_meshes.begin();
    const std::vector<AssimpMesh *>::const_iterator iEnd = m_meshes.end();

    program.bind();
    program.setUniformValue("model", m_transform * m_normalize);

    for (; i != iEnd; ++i)
    {
        AssimpMesh * mesh(*i);

        program.setUniformValue("diffuse", mesh->material.diffuse);
        program.setUniformValue("ambient", mesh->material.ambient);
        program.setUniformValue("specular", mesh->material.specular);
        program.setUniformValue("emissive", mesh->material.emissive);
        program.setUniformValue("shininess", mesh->material.shininess);
        program.setUniformValue("texCount", mesh->material.texCount);

        if (mesh->material.texCount > 0)
        {
            program.setUniformValue("difftex", 0);
            gl.glActiveTexture(GL_TEXTURE0);            
            gl.glBindTexture(GL_TEXTURE_2D, mesh->material.texture);
        }

        mesh->vao.bind();
        gl.glDrawElements(mode, mesh->faces * 3, GL_UNSIGNED_INT, nullptr);
        mesh->vao.release();

        if (mesh->material.texCount > 0)
            gl.glBindTexture(GL_TEXTURE_2D, 0);
    }
    program.release();
}

//! [5]
void TriangleWindow::render()
{
    const qreal retinaScale = devicePixelRatio();
    glViewport(0, 0, width() * retinaScale, height() * retinaScale);

    glClear(GL_COLOR_BUFFER_BIT);

    m_program->bind();

    QMatrix4x4 matrix;
    matrix.perspective(60.0f, 4.0f/3.0f, 0.1f, 100.0f);
    matrix.translate(0, 0, -2);
    matrix.rotate(100.0f * m_frame / screen()->refreshRate(), 0, 1, 0);

    m_program->setUniformValue(m_matrixUniform, matrix);

    GLfloat vertices[] = {
        0.0f, 0.707f,
        -0.5f, -0.5f,
        0.5f, -0.5f
    };

    GLfloat colors[] = {
        1.0f, 0.0f, 0.0f,
        0.0f, 1.0f, 0.0f,
        0.0f, 0.0f, 1.0f
    };

    glVertexAttribPointer(m_posAttr, 2, GL_FLOAT, GL_FALSE, 0, vertices);
    glVertexAttribPointer(m_colAttr, 3, GL_FLOAT, GL_FALSE, 0, colors);

    glEnableVertexAttribArray(0);
    glEnableVertexAttribArray(1);

    glDrawArrays(GL_TRIANGLES, 0, 3);

    glDisableVertexAttribArray(1);
    glDisableVertexAttribArray(0);

    m_program->release();

    ++m_frame;
}

void Painter::renderScene(const Camera &camera)
{
    m_envMap->paint(camera);

    /* Paint gems */
    QOpenGLShaderProgram *gemProgram = (*m_shaderPrograms)[ShaderPrograms::GemProgram];
    gemProgram->bind();

    gemProgram->enableAttributeArray(0);
    gemProgram->enableAttributeArray(1);

    gemProgram->setUniformValue("envmap", 0);
    gemProgram->setUniformValue("gemStructureMap", 1);
    gemProgram->setUniformValue("rainbowMap", 2);
    gemProgram->setUniformValue("eye", camera.eye());
    gemProgram->setUniformValue("viewProjection", camera.viewProjection());
    m_gl->glActiveTexture(GL_TEXTURE0);
    m_gl->glBindTexture(GL_TEXTURE_CUBE_MAP, m_envMap->cubeMapTexture());
    m_gl->glActiveTexture(GL_TEXTURE1);
    m_gl->glBindTexture(GL_TEXTURE_CUBE_MAP, m_gemStructureMap->cubeMapTexture());
    m_gl->glActiveTexture(GL_TEXTURE2);
    m_gl->glBindTexture(GL_TEXTURE_CUBE_MAP, m_rainbowMap->cubeMapTexture());

    QHash<ShaderPrograms, QOpenGLShaderProgram*> shaderPrograms;
    shaderPrograms.insert(ShaderPrograms::GemProgram, m_shaderPrograms->value(ShaderPrograms::GemProgram));
    shaderPrograms.insert(ShaderPrograms::LighRayProgram, m_shaderPrograms->value(ShaderPrograms::LighRayProgram));

    m_sceneRenderer->paint(*m_gl, camera.viewProjection(), shaderPrograms);

    m_gl->glActiveTexture(GL_TEXTURE0);
    m_gl->glBindTexture(GL_TEXTURE_CUBE_MAP, 0);
    m_gl->glActiveTexture(GL_TEXTURE1);
    m_gl->glBindTexture(GL_TEXTURE_CUBE_MAP, 0);
    m_gl->glActiveTexture(GL_TEXTURE2);
    m_gl->glBindTexture(GL_TEXTURE_CUBE_MAP, 0);
    m_gl->glBindTexture(GL_TEXTURE_2D, 0);

    gemProgram->disableAttributeArray(0);
    gemProgram->disableAttributeArray(1);

    gemProgram->release();
}

// Wireframe OpenGL drawing
void 
Scene_polylines_item::drawEdges(CGAL::Three::Viewer_interface* viewer) const {
    if(!are_buffers_filled)
    {
        computeElements();
        initializeBuffers(viewer);
    }

    vaos[Edges]->bind();
    attribBuffers(viewer, PROGRAM_NO_SELECTION);
    QOpenGLShaderProgram *program = getShaderProgram(PROGRAM_NO_SELECTION);
    program->bind();
    program->setAttributeValue("colors", this->color());
    viewer->glDrawArrays(GL_LINES, 0, static_cast<GLsizei>(nb_lines/4));
    program->release();
    vaos[Edges]->release();
    if(d->draw_extremities)
    {
       Scene_group_item::drawEdges(viewer);
    }

}

// Build a passthrough glsl program
QOpenGLShaderProgram* GLImageProcessor::buildPassthorughProgram() const
{
	QOpenGLShaderProgram* prog = new QOpenGLShaderProgram();

	QOpenGLShader *vshader = new QOpenGLShader(QOpenGLShader::Vertex, prog);
	const char *vsrc =
		"attribute highp vec4 in_Vertex;\n"
		"attribute mediump vec4 in_TexCoord;\n"
		"varying mediump vec4 texCoord;\n"
		"void main(void)\n"
		"{\n"
		"    gl_Position = in_Vertex;\n"
		"    texCoord = in_TexCoord;\n"
		"}\n";
	vshader->compileSourceCode(vsrc);


	QOpenGLShader *fshader = new QOpenGLShader(QOpenGLShader::Fragment, prog);
	const char *fsrc =
		"uniform sampler2D in_Texture;\n"
		"varying mediump vec4 texCoord;\n"
		"void main(void)\n"
		"{\n"
		"    gl_FragColor = texture2D(in_Texture, texCoord.st);\n"
		"}\n";
	fshader->compileSourceCode(fsrc);

	prog->addShader(vshader);
	prog->addShader(fshader);
	prog->bindAttributeLocation("in_Vertex", 0);
	prog->bindAttributeLocation("in_TexCoord", 1);
	prog->link();
	prog->bind();
	prog->setUniformValue("in_Texture", 0);
	prog->release();

	return prog;
}

void Viewer::drawVisualHints()
{

    CGAL::QGLViewer::drawVisualHints();

    if(d->distance_is_displayed)
    {
        glDisable(GL_DEPTH_TEST);
        QMatrix4x4 mvpMatrix;
        double mat[16];
        camera()->getModelViewProjectionMatrix(mat);
        for(int i=0; i < 16; i++)
        {
          mvpMatrix.data()[i] = (float)mat[i];
        }
        if(!isOpenGL_4_3())
        {
          //draws the distance
          //nullifies the translation
          d->rendering_program_dist.bind();
          d->rendering_program_dist.setUniformValue("mvp_matrix", mvpMatrix);
          d->rendering_program_dist.setUniformValue("point_size", GLfloat(6.0f));
          d->vao.bind();
          glDrawArrays(GL_POINTS, 0, static_cast<GLsizei>(2));
          glDrawArrays(GL_LINES, 0, static_cast<GLsizei>(2));
          d->vao.release();
          d->rendering_program_dist.release();
          glEnable(GL_DEPTH_TEST);
        }
        else
        {          
          QOpenGLShaderProgram* program = getShaderProgram(PROGRAM_SOLID_WIREFRAME);
          program->bind();
          QVector2D vp(width(), height());
          program->setUniformValue("viewport", vp);
          program->setUniformValue("near",(GLfloat)camera()->zNear());
          program->setUniformValue("far",(GLfloat)camera()->zFar());
          program->setUniformValue("width", GLfloat(3.0f));
          program->setAttributeValue("colors", QColor(Qt::black));
          program->setUniformValue("mvp_matrix", mvpMatrix);
          QMatrix4x4 f_mat;
          f_mat.setToIdentity();
          program->setUniformValue("f_matrix", f_mat);
          d->vao.bind();
          glDrawArrays(GL_LINES, 0, static_cast<GLsizei>(2));
          d->vao.release();
          program->release();
          
          program = getShaderProgram(PROGRAM_NO_SELECTION);
          program->bind();
          program->setAttributeValue("colors", QColor(Qt::black));
          program->setAttributeValue("point_size", 6.0f);
          program->setUniformValue("mvp_matrix", mvpMatrix);
          program->setUniformValue("f_matrix", f_mat);
          d->vao.bind();
          glDrawArrays(GL_POINTS, 0, static_cast<GLsizei>(2));
          d->vao.release();
          program->release();
        }

    }
    if (!d->painter->isActive())
      d->painter->begin(this);
    //So that the text is drawn in front of everything
    d->painter->beginNativePainting();
    glDisable(GL_DEPTH_TEST);
    d->painter->endNativePainting();
    //Prints the displayMessage
    QFont font = QFont();
    QFontMetrics fm(font);
    TextItem *message_text = new TextItem(float(10 + fm.width(d->message)/2),
                                          float(height()-20),
                                          0, d->message, false,
                                          QFont(), Qt::gray );
    if (d->_displayMessage)
    {
      d->textRenderer->addText(message_text);
    }
    d->textRenderer->draw(this);
    
    if (d->_displayMessage)
      d->textRenderer->removeText(message_text);
}