[prewett]

It not even a drawing API, even. It's a 3D triangle rendering API. Things like lines, bezier curves, gradients are all do-it-yourself. None of it super-hard, I've done them all, but before you write your UI you have to write all your drawing routines, which probably wasn't what you wanted to be doing. And you get all the fun texture management issues for any gradients and images you want to display. And you probably won't have optimized it like the platform rendering will have.

And then there's text... You've got to load a texture for every glyph of every point size used in the app for every font used in the app. Mind you, the OS already has a cache for this, but you don't have access to it, so that's more memory wasted. Which would be sizeable if every app on your system was using Japanese, or worse, Chinese, and making a copy of all this stuff.

[afiori]

it isn't the main point of your comment... but why is Chinese worse than Japanese? is it about the font itself being different or about Chinese text containing on average more unique characters?

[prewett]

More characters. I believe there are a mandated 2000 characters that learned in school and used by newspapers. I believe 3000 Chinese characters only gets to 97% and 5000 is still 99.44% [0]

[0] https://lingua.mtsu.edu/chinese-computing/statistics/char/li...