The below screenshot doesn't look like much, but it shows a few things:
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The active GameState passes a std::vector of Entities to the Renderer, which sorts all the entities with a RenderableComponent into batches, and then renders each batch (currently with a crappy flat-color shader). Color and transformation are instanced data. There are multiple instances of two meshes: a straight wall section and a right-angle wall section. One wall section is colored differently, and the bottom wall section is non-uniformly scaled to stretch from one angle to the other.
Eventually I'll transform the maze bits once at the beginning and store the transformed data in a larger buffer, since it's static. But now it serves a useful purpose letting me test the Renderer changes as I make them.
I wish I were more productive with my time, and had more time to spend, but I've decided to choose sedatives over coding on my sleepless nights (in the interest of promoting good mental health), and my days are surprisingly filled with other things that need to be done while the rest of the world is predisposed to social interaction.