In the linked issue, only on Mac OSX, Citra would leak memory from the hardware renderer. This means performance and features can vary widely between operating systems, graphics driver, and the physical graphics card.Īs you might have guessed, this leads to some OS specific bugs that are very hard to track down. OpenGL is also great for emulator developers because it’s a cross-platform standard for graphics, with support for all major desktop platforms.īut because OpenGL is just a specification, every vendor is left up to their own to make their drivers support the specification for every individual platform. The infamous Pokémon outlines bug was one such example of something that OpenGL just doesn’t handle well

This leads to cases where sometimes we just have to live with minor inaccuracies as a tradeoff for speed. That said, we tend to run into edge cases that the PICA200 supports, but frankly, OpenGL is not well suited to support. Whenever the tasks the PICA200 can perform matches up with tasks you can do on a GPU using OpenGL, everything is fast and everyone is happy! For a hardware renderer, Citra isn’t using the GPU much!Īs a general rule of thumb, CPUs are fast at computing general tasks, while GPUs are blazing fast at computing very specific tasks. The green shaded portions are what Citra emulates using the GPU.

To understand why, we need to dive a little deeper into the difference between CPUs and modern GPUs. Challenges in the Hardware RendererĮarlier it was stated that the OpenGL hardware renderer was emulating the PICA200 by using the GPU instead of the CPU, and … that’s only partially true.Īs it stands, only a portion of the PICA200 emulation is running on the GPU most of it is running on the CPU! However, it’s not all sunshine and daisies there’s always tradeoffs in software development.

On the other hand, the second video is using the OpenGL hardware renderer, which emulates the PICA200 by using your computer’s GPU.įrom those videos, using your GPU to emulate the 3DS GPU is the clear winner when it comes to speed! The first video is showing off the software renderer, which emulates the PICA200 by using your computer’s CPU. The speed difference boils down to how the 3DS GPU is being emulated. Why is there such a major difference in speed from the first and the second video? Good thing that shield flashing bug still isn’t around

Citra on switch