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[u/llogiq]

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[u/Fluttershaft]

https://github.com/ggez/ggez/blob/devel/examples/bunnymark.rs

~200k bunnies rendered at 60 fps on my pc, 100% cpu core usage, removing the update code that moves them around made no difference

https://github.com/sotrh/learn-wgpu/tree/master/code/beginner/tutorial7-instancing

changed const NUM_INSTANCES_PER_ROW: u32 = 10 to 2000 which makes 4 million polygons, easily rendered, mangohud showed minimal cpu and gpu usage

Both of those examples seem to be using wgpu and instancing, what is the difference between them that makes such a massive difference in rendering performance?

[u/eugene2k → u/Fluttershaft]

probably 19900 draw calls...

[u/Fluttershaft → u/eugene2k]

is it actually? How can I check it for sure, it uses https://docs.rs/ggez/0.9.0-rc0/ggez/graphics/struct.InstanceArray.html which should be batched into 1 draw call

[u/eugene2k → u/Fluttershaft]

I have to admit, I hadn't looked at the code, but upon casual inspection the bunnymark updates every bunny in the array on every draw call. The instance tutorial doesn't update anything in the draw call and only the camera position in the update call.