void copyFBOToPBO()

in mujoco_py/gl/eglshim.c [231:288]
44 lines of code
8 McCabe index (conditional complexity)

void copyFBOToPBO(mjrContext* con,
                  unsigned int pbo_rgb, unsigned int pbo_depth,
                  mjrRect viewport, int bufferOffset)
{
    GLbitfield mask = (pbo_rgb ? GL_COLOR_BUFFER_BIT : 0) |
                      (pbo_depth ? GL_DEPTH_BUFFER_BIT : 0);

    if (!mask)
        return;

    // multisample: blit to resolve buffer and read from there
    if (con->offSamples)
    {
        // make sure blit is supported
        if( !glBlitFramebuffer )
            return;

        // prepare for resolve-blit
        glBindFramebuffer(GL_READ_FRAMEBUFFER, con->offFBO);
        glReadBuffer(GL_COLOR_ATTACHMENT0);
        glBindFramebuffer(GL_DRAW_FRAMEBUFFER, con->offFBO_r);
        glDrawBuffer(GL_COLOR_ATTACHMENT0);

        // resolve-blit
        glBlitFramebuffer(viewport.left, viewport.bottom,
                          viewport.left + viewport.width, viewport.bottom + viewport.height,
                          viewport.left, viewport.bottom,
                          viewport.left + viewport.width, viewport.bottom + viewport.height,
                          mask, GL_NEAREST);

        // read from resolved
        glBindFramebuffer(GL_READ_FRAMEBUFFER, con->offFBO_r);
    }
    // no multisample: read from offscreen
    else
        glBindFramebuffer(GL_READ_FRAMEBUFFER, con->offFBO);

    glReadBuffer(GL_COLOR_ATTACHMENT0);
    if (pbo_rgb) {
        glBindBuffer(GL_PIXEL_PACK_BUFFER_ARB, pbo_rgb);
        glReadPixels(viewport.left, viewport.bottom, viewport.width, viewport.height,
                     GL_RGB, GL_UNSIGNED_BYTE,
                     bufferOffset * viewport.width * viewport.height * 3);
        glBindBuffer(GL_PIXEL_PACK_BUFFER_ARB, 0);
    }
    if (pbo_depth) {
        glBindBuffer(GL_PIXEL_PACK_BUFFER_ARB, pbo_depth);
        glReadPixels(viewport.left, viewport.bottom, viewport.width, viewport.height,
                     GL_DEPTH_COMPONENT, GL_UNSIGNED_SHORT,
                     bufferOffset * viewport.width * viewport.height * sizeof(short));
        glBindBuffer(GL_PIXEL_PACK_BUFFER_ARB, 0);
    }

    // restore currentBuffer
    glBindFramebuffer(GL_FRAMEBUFFER, con->offFBO);
    glReadBuffer(GL_COLOR_ATTACHMENT0);
    glDrawBuffer(GL_COLOR_ATTACHMENT0);
}