Hello dear Anicca,
Yes is the result of meditation, but not in that 'the dream it self is true', but your concentration on it make it's true.
Technicaly, the mirrow of your mind become calm, there is no more waves that changes a reflect, so the reflection becomes clear and right, your calm mind dont make any modification, so the light of your consciousness takes a right forms, and you remark the exactitude of ressemblances between internal dhammas and external. Dhamma dont make any distinction between external and internal, if there is a consciousness on one or another dhamma, this dhamma take the name-and-form.
All dhammas are like a shadows
So if you want to play with the shadows of your mind, you can do.
To test, try the next time to concentrate your clear mind on one litte detail, dirrect the boat of your mind on it, and the wind of kamma will lead your body to it.
If you dont want to play, dont concentrate your mind on it. If you dont wanna see something, dont enlight it.
Dreams are just a dreams, the moment when our bain reogrganise the memory, this activity is 'detected' by consciousness, images apears, that at the same moment goes in memory too... Dreams are not-self, just reorganisation, harmonysation, optimisation of memory space in your brain, so if you dont wonna to see your dreams become true, dont make it become true.