Every new semester() we have to develop a game in a group which is our semester project. This semester my team and I developed a puzzle game. The game is about a virus that has to hack into a computer system. The Game is a 2D topdown and for that reason we decided to use tilemaps for our leveldesign process. When I was creating the tilemap editor for the game, Unity didn't have tilemap editor. With the newest version they implemented a great tilemap editor which is very useful. I absolutely recommend using the new build in editor. Though if you want to master your own fancy tilemap editor then you have to start learning editor scripting now! You wouldn't expect the possiblities Unity provides to customize your editor.
First of all I build this tool for our designers. With this tool they are able to design faster and better levels. If you have a game with many levels I would always recommend to build tools for your designers (when unity doesn't have a similiar tool). But back to the code. Here is the code for drawing a grid in the scene view:
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