Do you think sprite sheet optimization beyond what Construct 2 already does is worth it for mobile?
So here's the deal: Construct 2 currently sacrifices some sprite sheet optimization in the interest of greater compatibility. For example, instead of creating larger more condensed sprite sheets, it creates one sprite sheet for each sprite. To my understanding, it does this primarily to support progress bar feedback. Since there is no way to tell how much of an individual image is downloaded, splitting sprite sheets up allows Construct 2 to count how many of them are loaded from the total, giving a more precise picture of the load progress.
This decision makes sense when considering that Construct 2 was made for HTML-5 games, which are typically "downloaded" rather than "loaded from disk". However, I believe many people are using the engine now primarily for mobile game development (like me). This means the games will be running on less performant GPUs, but will load much faster since they don't have to be downloaded. These lower-end GPUs could benefit from not having to swap textures as often as they would with multiple spritesheets, and the "progress-bar feedback" reasoning here is not as compelling as it is for browser games.
So for mobile-only developers, it would be nice to have the option to pack the sprite sheets manually, with the aid of tools like Texture Packer. Construct 2 games on mobile might consequently see lower memory usage, better GPU performance, and on the whole more native-like experiences.
Now, I do remember reading that Ashley was unable to measure any performance difference between using one giant spritesheet and using multiple ones. However, I don't think the test he used is always an accurate profiler of GPU performance, because the test averages the framerate as reported by the CPU. In my mobile game, despite a reported framerate that's generally 60 or higher, there is persistent stuttering and frame dropping that makes the game look bad. I hope it's just JIT compilation that will be fixed soon, but I've learned to choose skepticism over hope. It seems like there could be something crazy going on with the GPU here that the CPU doesn't seem to capture. That's why I don't completely trust this idea that sprite sheets make no difference. If there is room for optimization that could theoretically help GPU performance, I'd like to experiment with it.
What do you guys think?