I made a part of a castle in singleplayer, then saved it as a schematic and went onto a creative server so i could use WorldEdit. When I tried to print the schematic, it gave me this.

This is an image of the original castle.

I have never used Schematica before, so it very well might have something to do with the settings. I've seen people use Schematica on this server before, so it's not that.

Edit: I tried deleting and re-downloading Schematica and it gave me the exact same conglomerate of textures.

Thank you! Turning "Use VBOs" off worked.

Duplicate of #258; remove optifine or try toggling VBOs.