Question

Qt 5.8.0。 MinGW 32位。我需要在屏幕上绘制不同形状的对象。我使用OpenGL来加速和绘制不同的形状，但我还需要绘制QPaint。我尝试用Qpainter（drawText函数）绘制Rect。屏幕上显示文字，但屏幕上没有显示。

实施例

如何使用QPainter绘制矩形，而不是使用OpenGL？我想绘制3个形状：使用OpenGL的三角形和矩形，使用QPainter的矩形。我的应用程序应绘制任何形状（使用QPainter），有时使用OpenGL加速绘制粒子。如何在一个小部件中组合它？

DrawingWidget.cpp的一部分：

public function scopeGetQuestion($query)
    {

       return $query->join('question_chapter_rel', 'chapters.id', '=' ,'question_chapter_rel.chapter_id')
                    ->join('questions','questions.id', '=' ,'question_chapter_rel.question_id')
                    ->join('answers','answers.id', '=' ,'questions.correct_answers')
            ->select(
                [
                    'chapters.id',
                    'chapters.chapter_description',
                    'questions.id',
                    'questions.question_description',
                    'answers.id',
                    'answers.answer_description'
                ]
            )

            ->where('answers.is_correct',1)
            ->paginate(12);
    }

主：

select `chapters`.`id`, `chapters`.`chapter_description`, `questions`.`id`, `questions`.`question_description`, `answers`.`id`, `answers`.`answer_description`

from `chapters`
Inner Join `question_chapter_rel`
on `chapters`.`id` = `question_chapter_rel`.`chapter_id`

Inner Join `questions`
on `questions`.`id` = `question_chapter_rel`.`question_id`

Inner Join `answers`
on `answers`.`id` = `questions`.`correct_answers`

where `answers`.`is_correct` = 1

17年4月18日

ahaha，所以，当我在绘制文本应用程序工作后绘制到rect时，如果我尝试在rect后绘制文本或尝试绘制rect而不使用文本，则无效

void DrawingWidget::paintGL()
{
    m_painter = new QPainter(this);
    m_painter->beginNativePainting();
    m_program->bind();
    m_modelView.setToIdentity();
    m_modelView.translate(-1.5f, 0.0f, -6.0f);
    m_program->setUniformValue("mvpMatrix", m_projection * m_modelView);
    glBindBuffer(GL_ARRAY_BUFFER, m_vboIds[0]);
    m_program->enableAttributeArray(m_posAttr);
    m_program->setAttributeBuffer(m_posAttr, GL_FLOAT, 0, 3);
    glBindBuffer(GL_ARRAY_BUFFER, m_vboIds[1]);
    m_program->enableAttributeArray(m_colAttr);
    m_program->setAttributeBuffer(m_colAttr, GL_FLOAT, 0, 3);
    glDrawArrays(GL_TRIANGLES, 0, 3);

    m_modelView.translate(3.0f, 0.0f, 0.0f);
    m_program->setUniformValue("mvpMatrix", m_projection * m_modelView);
    glBindBuffer(GL_ARRAY_BUFFER, m_vboIds[2]);
    m_program->enableAttributeArray(m_posAttr);
    m_program->setAttributeBuffer(m_posAttr, GL_FLOAT, 0, 3);
    glBindBuffer(GL_ARRAY_BUFFER, m_vboIds[3]);
    m_program->enableAttributeArray(m_colAttr);
    m_program->setAttributeBuffer(m_colAttr, GL_FLOAT, 0, 3);
    glDrawArrays(GL_TRIANGLE_STRIP, 0, 4);
    m_program->release();
    m_painter->endNativePainting();
    drawText();
    m_painter->end();
}

void DrawingWidget::drawText()
{
    m_painter->setPen(QColor(Qt::green));
    m_painter->setBrush(QBrush(QColor(Qt::red)));
    m_painter->drawRect(QRect(QPoint(10, 10), QPoint(50, 44)));
    m_painter->drawText(0, 40, QString("TEST"));
}

我可以用QPainter绘制QRect并用OpenGL绘制一些东西吗？

0 个答案: