A Nintendo Switch port of The Witcher 3 was thought to be almost impossible, but CD Projekt Red and Saber Interactive made the impossible happen, releasing a very good port that's great especially for the console's handheld mode. The initial port, however, was far from being the game we got last month.
Speaking with GamesBeat, Saber Interactive CEO Matthew Karch spoke of the challenges of bringing The Witcher 3 on Nintendo Switch. The initial port ran at 10 FPS on the console, used more memory than the console has and the build size was over 50 GB big.
Cutting some of the things that made the game The Witcher 3, such as NPC number, wasn't possible, so the team had to be creative, coming up with some clever solutions for shadows and vegetations to improve performance.
One of the things we knew we had to change for Switch was how the engine calculates shadows from the sun. Shadows are obviously essential for creating a realistic look for huge outdoor levels, but the off-the-shelf solution was prohibitively expensive on Switch. We had to combine a blend of static shadowmap, terrain lightmap, and dynamic shadowmap to achieve a similar look to the original.
In outdoor environments, foliage can make up about 50% of all the visuals. We had to rewrite the algorithm for how grass is generated and rendered. We also had to change [levels-of-detail for] trees, lighting, and shadows to keep the overall look and performance as close to the original as possible.
The Witcher 3 is now available on Nintendo Switch as well as on PC, PlayStation 4 and Xbox One. The Nintendo Switch release comes complete with all the additional content released post-launch, including the excellent Hearts of Stone and Blood and Wine expansions, which add new areas, gameplay mechanics and more.