QT OpenGL 天空盒

正常加载shader program 就是图片不一样了 立方体贴图 可以看看learnopengl

QT里面封装了

QOpenGLTexture

这个类设置target就可以加载立方体贴图

initTextures()

{

        const QImage posx = QImage(":/left.jpg").mirrored().convertToFormat(QImage::Format_RGBA8888);

        const QImage posy = QImage(":/bottom.jpg").mirrored().convertToFormat(QImage::Format_RGBA8888);

        const QImage posz = QImage(":/front.jpg").mirrored().convertToFormat(QImage::Format_RGBA8888);

        const QImage negx = QImage(":/right.jpg").mirrored().convertToFormat(QImage::Format_RGBA8888);

        const QImage negy = QImage(":/top.jpg").mirrored().convertToFormat(QImage::Format_RGBA8888);

        const QImage negz = QImage(":/back.jpg").mirrored().convertToFormat(QImage::Format_RGBA8888);

      enviroment = new QOpenGLTexture(QOpenGLTexture::TargetCubeMap);

      enviroment->create();

      enviroment->setSize(posx.width(), posx.height(), posx.depth());

      enviroment->setFormat(QOpenGLTexture::RGBA8_UNorm);

      enviroment->allocateStorage();

      enviroment->setData(0, 0, QOpenGLTexture::CubeMapPositiveX,

                         QOpenGLTexture::RGBA, QOpenGLTexture::UInt8,

                         (const void*)posx.constBits(), 0);

      enviroment->setData(0, 0, QOpenGLTexture::CubeMapPositiveY,

                         QOpenGLTexture::RGBA, QOpenGLTexture::UInt8,

                         (const void*)posy.constBits(), 0);

      enviroment->setData(0, 0, QOpenGLTexture::CubeMapPositiveZ,

                         QOpenGLTexture::RGBA, QOpenGLTexture::UInt8,

                         (const void*)posz.constBits(), 0);

      enviroment->setData(0, 0, QOpenGLTexture::CubeMapNegativeX,

                         QOpenGLTexture::RGBA, QOpenGLTexture::UInt8,

                         (const void*)negx.constBits(), 0);

      enviroment->setData(0, 0, QOpenGLTexture::CubeMapNegativeY,

                         QOpenGLTexture::RGBA, QOpenGLTexture::UInt8,

                         (const void*)negy.constBits(), 0);

      enviroment->setData(0, 0, QOpenGLTexture::CubeMapNegativeZ,

                         QOpenGLTexture::RGBA, QOpenGLTexture::UInt8,

                         (const void*)negz.constBits(), 0);

      enviroment->generateMipMaps();

      enviroment->setWrapMode(QOpenGLTexture::ClampToEdge);

      enviroment->setMinificationFilter(QOpenGLTexture::LinearMipMapLinear);

      enviroment->setMagnificationFilter(QOpenGLTexture::LinearMipMapLinear);

    glEnable(GL_TEXTURE_CUBE_MAP_SEAMLESS);

}

然后就可以把这个用于贴图了

glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);

    enviroment->bind();

    //glBindTexture(GL_TEXTURE_CUBE_MAP, skyID);

    //glDepthMask(GL_FALSE);

    glDepthFunc(GL_LEQUAL);

    QMatrix4x4 matrix;

    matrix.setToIdentity();

  matrix.scale(10,10);

    view.lookAt(QVector3D(0,0,0.0),QVector3D(0,0,0),QVector3D(0,-1,0));

     view.rotate(rotation);

    if (!program.bind())

        close();

    program.setUniformValue("pv_matrix", projection*view*matrix);

    //! [6]

    program.setUniformValue("skybox", 0);

    _painter->paintSkyBox(&program);//自己写个类drawArray

    glDepthFunc(GL_LESS);

VERT

#ifdef GL_ES

precision mediump int;

precision mediump float;

#endif

uniform mat4 pv_matrix;

attribute vec3 a_position;

varying vec3 v_texCoord;

void main()

{

    gl_Position=pv_matrix*vec4(a_position,1.0);

    v_texCoord=a_position;

}

FRAG

#ifdef GL_ES

// Set default precision to medium

precision mediump int;

precision mediump float;

#endif

uniform samplerCube skybox;

varying vec3 v_texCoord;

void main()

{

    gl_FragColor= textureCube(skybox, v_texCoord);

}