If I ever start a world, it turns out fine. I sometimes get bored of a world and leave. When I join a different world, it seems normal until I move around a bit. Some chunks (I don't really know how big a chunk is but I think its the size like in the picture.) are copied all over the world. The chunk part can be anywhere. It could be in the air or on the ground. This makes some blocks invisible. It repeatedly changes the 1 chunk every tick (I also don't know how long a tick is but I estimated.) to a different chunk. Although I am using a resource pack, I knew that couldn't have been the problem since this was happening before I downloaded it. I've tried reloading the chunks but it doesn't change anything. This can be fixed by me logging off and logging back in, but I want to know if there is a simpler way. This also happens to me when I join servers or if I get kicked out of a multiplayer game and join back. I asked my friends when this happened to me if they saw it too. They said "No, it didn't." I also asked if it had ever happened to them. They also replied, "No, it hasn't." It might just be my computer. The chunks can also freeze at times and start repeating again. This happens in Minecraft 1.9 through 1.10+
(And apparently, this changes the textures for other things too...)