Someone

  if (pn_rc->actuator)
    {
      GLuint texture_id;

      // set the viewport to a texture size
      glViewport(0, 0, 128, 128);

      // run actuators
      exec_actuator (pn_rc->actuator);

      // copy prerendered frame to texture
      glGenTextures(1, &texture_id);
      glBindTexture(GL_TEXTURE_2D, texture_id);
      glTexImage2D(GL_TEXTURE_2D, 0, 4, 128, 128, 0, GL_RGBA, GL_UNSIGNED_BYTE, NULL);
      glCopyTexImage2D(GL_TEXTURE_2D, 0, GL_RGBA, 0, 0, 128, 128, 0);

      // reset the viewport to window size and render the pre-rendered image
      // 100% prerendered! yeah!!!
      glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);

      glViewport(0, 0, pn_image_data->width, pn_image_data->height);

      glBegin(GL_QUADS);

      glColor4f(1.0f, 1.0f, 1.0f, 1.0f);

      glTexCoord2f(0, 1);
      glVertex2i(-1, -1);
      glVertex2i(-1, 1);
      glVertex2i(1, 1);
      glVertex2i(1, -1);

      glEnd();

      glBindTexture(GL_TEXTURE_2D, 0);
      glDeleteTextures(1, &texture_id);

      SDL_GL_SwapBuffers();
    }