OpenGL ES 2.0使用多个program

为什么80%的码农都做不了架构师？>>>   

在切换program时需要重新 bind() ，也就是glUseProgram(programId)，然后重新为各个着色器变量赋值，附代码如下

void Table::paint()

{

    static GLfloat vertices[] =

    {

        0, 0, .5f, .5f,

        -.5f, -.8f, 0, .9f,

        .5f, -.8f, 1, .9f,

        .5f, .8f, 1, .1f,

        -.5f, .8f, 0, .1f,

        -.5f, -.8f, 0, .9f

    };

    m_shaderProgram.bind();

    // position

    static int aPositionLocation = m_shaderProgram.attributeLocation("a_Position");

    m_shaderProgram.setAttributeArray(aPositionLocation, GL_FLOAT, vertices, 2, 4*sizeof(GLfloat));

    m_shaderProgram.enableAttributeArray(aPositionLocation);

    // texture

    static int aTextureCoordinate = m_shaderProgram.attributeLocation("a_TextureCoordinate");

    m_shaderProgram.setAttributeArray(aTextureCoordinate, GL_FLOAT, vertices + 2, 2, 4*sizeof(GLfloat));

    m_shaderProgram.enableAttributeArray(aTextureCoordinate);

    m_shaderProgram.setUniformValue("u_MvpMat", m_mvpMat);

    glDrawArrays(GL_TRIANGLE_FAN, 0, 6);

}

转载于:https://my.oschina.net/foohao/blog/683706