Texas used to do license checks quite frequently when I was younger. Every vehicle on a particular road would be stopped and the driver asked for a license. At some point that stopped, as I recall due to some court decision or other.

The only checkpoints I'm aware of in Texas now are the immigration checkpoints near the Mexican border. These aren't conducted by police officers, but rather by CBP. I, like many, believe these to be unconstitutional, but evidently the courts have ruled otherwise, so I stop and answer the questions along with everyone else. "Are you an American citizen?" Yes. "Is everyone else in the vehicle citizens or legal residents?" Yes. Then once the drug sniffing dog finishes its job, "Please proceed. Have a nice day." No ID is asked for or shown.

I imagine they catch more drug smugglers this way than they do illegal border crossers.

Hmm . . . random thought/question. I am always armed at the checkpoints, but have never informed the officer. Texas law requires that we inform law enforcement if we are stopped. I suppose I have technically broken the law several times. I just never really thought about it before. I guess next time I had better tell them just in case.

EDIT
Doing a bit of research I found that they are not authorized to enforce state law, so I'll just keep my mouth shut.