No - You can't shoot someone trespassing in your yard at night in Texas unless they are attempting to steal, vandalize or break in.
The use of deadly force to protect property is contained in Texas Penal Code§9.42. This section of the law lays out a couple of scenarios where you are justified in reasonably using deadly force to protect your property. The first is if someone is committing trespass or interference with your property and you must reasonably use deadly force to prevent arson, burglary, robbery, aggravated robbery, theft during the night time or criminal mischief during the night time. If someone is unlawfully on your property and attempting to commit any of these crimes, you will gain the legal justification for using deadly force.
The second scenario is the law of recovering your property by using deadly force. Texas has a 3-prong test that, if met, gives a justification in using deadly force to recover stolen property. This test is as follows: (1) force is necessary to prevent or terminate another's trespass on land or unlawful interference with the property, (2) deadly force is reasonably necessary to prevent another who is immediately fleeing after committing burglary, robbery, aggravated robbery, or theft during the night time from escaping with the property, and (3) the person reasonably believes that the property cannot be recovered by any other method or that the use of non-deadly force to recover the property would expose them to a substantial risk of death or serious bodily injury. Lawyers cannot stress enough that under this scenario, while the law may allow you to use deadly force - It Is Most Likely A Very Bad Idea!
Criminal trespass alone is not one of the crimes listed in Texas Penal Code §9.42 or even as part of the "Castle Doctrine" under §9.31 or §9.32. A mere criminal trespass may, however, evolve into one of the above crimes where you may be justified in using deadly force to protect your property. If someone decides to sit on your lawn, you holler at them from your bedroom window to "get off my property." If the trespasser refuses to leave, you are almost certainly not justified in using deadly force to remove him. But if that person sitting on your lawn gets up and charges towards your bedroom window with a firearm and a crow bar, you will very likely be legally justified in using deadly force to protect yourself and your home. His actions of charging you with a weapon make him more than just a trespasser under Texas law.