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How can I verify that Pico-8 is running at full speed? I installed it on my netbook and I think I witnessed some slow-down. How do I tell if it is running at the intended speed?

Most emulators have an fps or percentage fps display. If it displays 100%, you know you are experiencing the speed of the original console.

That brings me to another point: Obviously some games are more CPU intensive than others. Does the Pico-8 specs specify a CPU clock or max CPU speed? I am asking because it would be nice to verify that my netbook's Atom chip is fast enough to run ANY possible future Pico-8 game, or to verify what machine I should purchase to ensure full speed Pico-8 compatibility.

P#27116 2016-08-20 13:26 ( Edited 2016-08-21 12:15)

To answer your first question, stat(1) returns the CPU usage for a given frame. If it's > 1, then the program is taking too long for it to draw at 30fps.

P#27138 2016-08-21 00:24 ( Edited 2016-08-21 04:24)

Things I'd also check:

Host OS CPU usage whilst Pico-8 is running.

api.p8 demo and check the timer is advancing evenly.

@zep has said that CPU heavy carts will run on a first gen Raspberry Pi.

But, regardless, it's worth reading into how CPU usage is calculated in Pico-8. Each operation is given a CPU cost. This is all fantasy and not related to the host CPU in any way.

P#27144 2016-08-21 04:35 ( Edited 2016-08-21 08:35)

I haven't found a game so far that didn't look smooth (presumably 30 fps) on a Raspberry Pi B+ with a 700 MHz Broadcom. I haven't tried adding stat() code to existing games to confirm I was getting the full frame rate, nor have I tried games using the new 60 fps mode. I just tried a cellular automata cart that reports the same stat(1) value >1 on both my Mac laptop (1.6 GHz) and a RaspPi (700 MHz). In an earlier thread we were speculating as to whether Pico-8 normalizes execution speed to a low common denominator, and while I wouldn't call this conclusive, I think it shows that netbook-caliber machines are sufficient Pico-8 host devices.

Pico-8 is still in alpha release, but I would expect its performance on low-end machines to improve over time, if anything.

P#27147 2016-08-21 05:12 ( Edited 2016-08-21 09:12)

AFAIK if it stats over 1 then it drops the frame rate to half (15 from 30)?

P#27150 2016-08-21 08:15 ( Edited 2016-08-21 12:15)

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