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my CHDK space bar indicator is off, what could create this?

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Offline Caefix

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Re: my CHDK space bar indicator is off, what could create this?
« Reply #10 on: 22 / November / 2019, 11:23:25 »
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return GetFreeCardSpaceKb()/GetTotalCardSpaceKb()*100;
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Offline srsa_4c

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Re: my CHDK space bar indicator is off, what could create this?
« Reply #11 on: 22 / November / 2019, 12:44:39 »
Quote from: Mlapse on 20 / November / 2019, 02:30:42
Code: [Select]
return (GetFreeCardSpaceKb()/GetTotalCardSpaceKb())*100;
Quote from: Caefix on 22 / November / 2019, 11:23:25
return GetFreeCardSpaceKb()/GetTotalCardSpaceKb()*100;
(smaller unsigned integer)/(larger unsigned integer)*100
Evaluated from left to right:
(smaller unsigned integer)/(larger unsigned integer) = 0
0 * 100 = 0
Try it and see.
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Offline Caefix

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Re: my CHDK space bar indicator is off, what could create this?
« Reply #12 on: 22 / November / 2019, 14:59:39 »
 :-X
return (int)((double)(GetFreeCardSpaceKb()/(double)GetTotalCardSpaceKb())*100);
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Offline srsa_4c

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Re: my CHDK space bar indicator is off, what could create this?
« Reply #13 on: 22 / November / 2019, 15:56:47 »
Quote from: Caefix on 22 / November / 2019, 14:59:39
return (int)((double)(GetFreeCardSpaceKb()/(double)GetTotalCardSpaceKb())*100);
The ARM CPU in our cameras has no floating point hardware, and most cameras have no hardware support for division either.
So,
floating point -> very slow
integer division -> slow
bit shift, multiplication -> ok.
The calculation in question is performed at least a dozen times per second and its precision is not critical: using integers allows for a tiny bit less CPU utilization.
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Online reyalp

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Re: my CHDK space bar indicator is off, what could create this?
« Reply #14 on: 22 / November / 2019, 16:57:06 »
FWIW, FP isn't THAT slow (https://chdk.setepontos.com/index.php?topic=12451.msg123421#msg123421), I wouldn't hesitate to use it here if required, but I completely agree with sticking to integer when it isn't
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Offline Mlapse

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Re: my CHDK space bar indicator is off, what could create this?
« Reply #15 on: 03 / December / 2019, 12:22:29 »
Quote from: srsa_4c on 21 / November / 2019, 16:58:55
I committed the above patch. Can you check whether it fixes the free space display?

I just started up 1.5/5296 and the bar looks as expected now, thank you.
it makes glancing at the cam good enough to check for space.
« Last Edit: 03 / December / 2019, 12:25:37 by Mlapse »
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