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

/******************************************************************************
* 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);
}

void csSurface::drawMesh(QOpenGLShaderProgram& program)
{
  if( _initRequired ) {
    initialize();
  }

  if( _meshInfo.isEmpty() ) {
    return;
  }

  program.setUniformValue("cs_DepthOffset", csCoordinateBox::DepthOffset);
  program.setUniformValue("cs_Model", _model);

  _surface->bind();
  const int vertexLoc = program.attributeLocation("cs_Vertex");
  program.enableAttributeArray(vertexLoc);
  program.setAttributeBuffer(vertexLoc, GL_FLOAT, 0, 3);

  const int colorLoc = program.attributeLocation("cs_Color");
  program.setAttributeValue(colorLoc, QColor(Qt::black));

  // Along x-Axis
  for(int y = 0; y < _meshInfo.rowCount(); y++) {
    glDrawArrays(GL_LINE_STRIP,
                 y*_meshInfo.columnCount(), _meshInfo.columnCount());
  }

  // Along y-Axis
  _meshY->bind();
  for(int x = 0; x < _meshInfo.columnCount(); x++) {
    const GLuint  offset  = sizeof(GLuint)*x*_meshInfo.rowCount();
    const GLvoid *indices = (GLvoid*)offset;
    glDrawElements(GL_LINE_STRIP, _meshInfo.rowCount(), GL_UNSIGNED_INT, indices);
  }
  _meshY->release();

  program.disableAttributeArray(vertexLoc);
  _surface->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);
    }

}

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);
}