iOS Question messuring code execution times

[sorex]

Hello,

is there an easy way to messure code execution time?

I have the impression that drawBitmap is a lot slower on IOS than on my cheap android phone.

in B4A/Android level creation was instant, in B4i/IOS it takes 2 seconds while the phone is more powerfull?

This is when using build release app so it's not a slowdown of debugger connections

 

[sorex]

@Erel :

It seems your drawBitmap sub is causing the slowdown.

I guess it's copying the full bitmap (640x1152px tileset) each time and then trims it to what is supposed to be left.

Are there other ways to copy a bitmap source rectangle to another bitmap?
(only copying the "selected" region)

 

[Erel]

There isn't any other way to draw part of an image. If you like upload your project and I will try it.

 

[sorex]

I pm'ed you a link to the project.

 

[Erel]

I highly recommend you to fix all the warnings. They are important and affect the performance.

About the speed of DrawBitmap:

Dim n As Long = DateTime.Now
DrawBitmap(MyCanvas,tiles,srcrect,dstrect)
Log("time: " & (DateTime.Now - n))

It takes here between 5 to 10 milliseconds.

 

[sorex]

will have a look at these after lunch.

 

[sorex]

I fixed most issues but 3 of them are incorrect.
(a sub is not called but it is from in another module, and 2 for a variable that's not set but it is during the init of the class)

It is still slower than on your (faster) phone tho.

but 10ms * 12 items = 1.2s while it would be instant with a normal regional bitmap copy.

it can probably be bypassed by

using seperate images for each tile instead of 1 big tilesheet where bitmap data gets copied from

or

using a get ready or level completed screen while the level gets build in the background

so more things to keep in mind when doing games

 

[stevel05]

10ms * 12 items = 1.2s

?

10ms * 12 items = 120ms still pretty instant I think.

 

[sorex]

right, I was thinking 10 hundreds of a second.

why am I getting this 2 seconds delay then? it's an iPhone 4s

 

[sorex]

I get 124 - 141ms here per object. (debug version)

 

[stevel05]

You can't reliably measure speed in debug, it could fluctuate wildly. What is the speed in Release mode, that's the important one.

 

[sorex]

can't read out the log like in b4a, but it take 1.5-2 seconds to build the level.

will check with an extra label, brb

 

[sorex]

going from 113 - 127 per object, so slightly faster