graphics.newImageSheet and RAM question

Getting Started Newbie Questions
#1

Hey guys,

I have a question regards to when the sprite sheet is loaded to memory?

I have a scene that contains lots of big sprite sheets, about 10 files of 1024x1024

The thing is, there is no scenario when 2 sprite sheets are used simultaneously, and also there is the fact that maybe not all of them will be used.

So thats why im asking about RAM, I want only the used sheets to be loaded to memory.

The way I set it up is like this for example:

[lua]
    local thunderOptions = {

        width =128,

        height = 128,

        numFrames = 64,

        sheetContentWidth = 1024, 

        sheetContentHeight = 1024,

        }

    local thunderSheet = graphics.newImageSheet ( “images/battleAttacks/thunderSheet.png” ,thunderOptions )

    local sequenceData = {

        – thunder ball 

            {    name = “thunderBall” ,sheet=thunderSheet ,frames = {1,2,3,4,5,6,5,4,5,6},loopCount = 1 ,time = 500 },

        

        – thunder from sky

            {    name = “thunderFromSky” ,sheet=thunderSheet ,frames = {10,11} ,time = 100 },

}

[/lua]

Is just by doing the code above, means that the sheet is already loaded to memory?

Then when im using this sheet I do :

[lua]local thunderFromSky = display.newSprite( thunderSheet, sequenceData )[/lua]

Hopefully only after this line of code the sheet is actually loaded.

One more question at the subject, is there a way to print to console the memory usage?

Currently im making a build and using instruments but its a lot of hassle.

Roy.

#2

Hi Roy,

Simply loading the sheet doesn’t increase the texture memory, but displaying images/frames from it will.

To test your texture memory, most people use this function, running on a timer or Runtime loop:

[lua]

local function checkMem()

    collectgarbage(“collect”)

    local memUsage_str = string.format( “MEMORY = %.3f KB”, collectgarbage( “count” ) )

    print( memUsage_str, "TEXTURE = "…(system.getInfo(“textureMemoryUsed”)/1048576) )

end

timer.performWithDelay( 1000, checkMem, 0 )

[/lua]

#3

Thanks for the fast reply!

Is texture memory any different from RAM usage? (only from the graphic point)

Cause im using 1024x1024 spriteSheets, but im getting a reading of only 

MEMORY = 308.811 KB    TEXTURE = 28.83203125

Is the  28.83203125 in mb? what is the different between “MEMORY” and “TEXTURE”?

And what are the limits of “MEMORY” and “TEXTURE”? on iPhone 4 (considering that its the lowest gen im targeting)

Thanks in advance

Roy.

#4

Hi Roy,

System memory and texture memory are different, yes. Have you read the guide which talks about this a bit?

http://docs.coronalabs.com/guide/basics/optimization/index.html

#5

@Bernet

Could you tell how newImageSheet behaves? Because you cannot perform remove on it, so I was wondering how it is managed in consideration of memory.

#6

@POM

[lua]system.getInfo(“textureMemoryUsed”)/1048576[/lua] will give you result in MB

system.getInfo( “maxTextureSize” ) will give you proper size (simulator will probably return this value for computer not device)

If I remember well, 25MB is the safe rule if you want to target even weak devices

from forum:

Values in the literature for iOS devices & single apps are the following:

installed memory: 128 MB --> memory warning threshold: 20-25 MB

installed memory: 256 MB --> memory warning threshold: 80-90 MB

installed memory: 512 MB --> memory warning threshold: 260-300 MB (estimated)

#7

Hi Roy,

Simply loading the sheet doesn’t increase the texture memory, but displaying images/frames from it will.

To test your texture memory, most people use this function, running on a timer or Runtime loop:

[lua]

local function checkMem()

    collectgarbage(“collect”)

    local memUsage_str = string.format( “MEMORY = %.3f KB”, collectgarbage( “count” ) )

    print( memUsage_str, "TEXTURE = "…(system.getInfo(“textureMemoryUsed”)/1048576) )

end

timer.performWithDelay( 1000, checkMem, 0 )

[/lua]

#8

Thanks for the fast reply!

Is texture memory any different from RAM usage? (only from the graphic point)

Cause im using 1024x1024 spriteSheets, but im getting a reading of only 

MEMORY = 308.811 KB    TEXTURE = 28.83203125

Is the  28.83203125 in mb? what is the different between “MEMORY” and “TEXTURE”?

And what are the limits of “MEMORY” and “TEXTURE”? on iPhone 4 (considering that its the lowest gen im targeting)

Thanks in advance

Roy.

#9

Hi Roy,

System memory and texture memory are different, yes. Have you read the guide which talks about this a bit?

http://docs.coronalabs.com/guide/basics/optimization/index.html

#10

@Bernet

Could you tell how newImageSheet behaves? Because you cannot perform remove on it, so I was wondering how it is managed in consideration of memory.

#11

@POM

[lua]system.getInfo(“textureMemoryUsed”)/1048576[/lua] will give you result in MB

system.getInfo( “maxTextureSize” ) will give you proper size (simulator will probably return this value for computer not device)

If I remember well, 25MB is the safe rule if you want to target even weak devices

from forum:

Values in the literature for iOS devices & single apps are the following:

installed memory: 128 MB --> memory warning threshold: 20-25 MB

installed memory: 256 MB --> memory warning threshold: 80-90 MB

installed memory: 512 MB --> memory warning threshold: 260-300 MB (estimated)

#12

Hi, 

I’ve made some tests with 

collectgarbage()

print( "MemUsage: " … collectgarbage(“count”) )

local textMem = system.getInfo( “textureMemoryUsed” ) / 1000000

print( "TexMem:   " … textMem )

in the enterFrame event, and according to the numbers shown, ‘graphics.newImageSheet’ increased TextMem by x amount.

After I nil the variables containing the ‘graphics.newImageSheet’ reference, the TexMem decreased the by x amount.

Example:

Increase TexTem

opt[8] = {width = 468, height = 250, numFrames = 1, sheetContentWidth = 468, sheetContentHeight = 250}

n1.p1 = graphics.newImageSheet(“1p.png”, opt[8])

Free TexMem

opt[8] = nil 

n1.p1 = nil

Cheers,

Ignacio

#13

Hi, 

I’ve made some tests with 

collectgarbage()

print( "MemUsage: " … collectgarbage(“count”) )

local textMem = system.getInfo( “textureMemoryUsed” ) / 1000000

print( "TexMem:   " … textMem )

in the enterFrame event, and according to the numbers shown, ‘graphics.newImageSheet’ increased TextMem by x amount.

After I nil the variables containing the ‘graphics.newImageSheet’ reference, the TexMem decreased the by x amount.

Example:

Increase TexTem

opt[8] = {width = 468, height = 250, numFrames = 1, sheetContentWidth = 468, sheetContentHeight = 250}

n1.p1 = graphics.newImageSheet(“1p.png”, opt[8])

Free TexMem

opt[8] = nil 

n1.p1 = nil

Cheers,

Ignacio