TexturePack *.txt format!

GregBUG

hey guys

anyone know the exactly "format" of texturePack text file ?

i mean:

in the text file


sprite1.bmp, 280, 222, 32, 52, 35, 23, 29, 21


"sprite1.bmp" ok it's sprite name...

280 is x offset in the texture pack ?
222 is y offset in the texture pack ?
32 is Width ?
52 is Height ?

35 ??
23 ??
29 ??
21 ??

any help ?

Scouser

@GregBUG: Looking back at this thread I think the values could be dx1, dy1, dx2, dy2 anthough I don't actually know what they mean, @atilim might be able to shed more light on the subject.

techdojo

I think the first two unknowns are the offsets from the top left corner - this is used when the texturePacker "shrink wrap" option is on, basically if you have an image that's 64x64 but the actual pixel area only takes up an 8x8 area in the middle, then texturePacker will work out the pixel areas bounding box within the image and only store the actual pixel area, the first two numbers allow the sprite draw code to actually draw the pixel area back at the correct position.

I suspect 3 & 4 might actually be the width and height of the "pixel area"

HTH

Jon...

GregBUG

thanks guys!
when i go back to home (now i'm at work) i'll try...
i keep you informed...

thanks!

atilim

@GregBUG,
dx1, dy1: amount of trimming from top-left
dx2, dy2: amount of trimming from bottom-right

+---------------------------+ | | | | dy1 | | | | | +-------+ | |<- dx1 ->| |<- dx2 ->| | +-------+ | | | | | dy2 | | | | +---------------------------+

@techdojo as exactly as you said, first two is used to draw at actual position and second two is needed to get actual width and height.

And if you don't select "Remove Alpha Border", the last 4 values are always 0.

Scouser

@atilim: Now it makes sense. Maybe I can now put this to use and save me some texture space

atilim

@Scouser exactly. It's always better to select "Remove Alpha Border" because original drawing position and width/height is preserved and your code works as before. Also it improves performance by not drawing the transparent pixels.

avo

ohhhhhhhhhhhhh I did not know that!

edit: while we are on texturepacks, is there a texturepack that's too big? The first time I made one I noticed the red dot next to the size and thought that meant it was too big, but I don't think that's the case? Is it ok to put all my backgrounds in a texture pack or should they just be handled separately?

alexzheng

Is there any performace difference between single texture pack and multiple textures.

MikeHart

is there a texturepack that's too big?

Yup, as soon as you go over the hardware limitation of the device you want to support, then it is to big.

MikeHart

Is there any performace difference between single texture pack and multiple textures.

Of course there is. The advantage of a texture pack is that OpenGL doesn't have to change textures if you use a them. Switching the texture takes some time so the less it does that, the better.

techdojo

As a general rule, most devices with have a max texture size of 1024x1024, best performance will always be achieved by putting all of your game / level assets on to a single page which will then avoid the OpenGL state change.

iOS Retina devices have a max texture size of 2048x2048 - not sure about the 3rd gen ipad - it *may* be 4096x4096 but that's just getting silly

MikeHart

IOS is predictable. On Android you will find all kinds of hardware features. For an example, my HTC Desire (bravo) has a max texture size of 4096x4096. But like @techdojo said, I would not go higher than 2024x2024. If you can, stay below. Especially if you have several texture packs your app has to switch constantly while it renders the content.