Any tips or definitive guide to export PNGs with Illustrator?

RubiWorks

Hello everybody. I´m using Illustrator every days but i have problems to undestand the exports to GameSalad.

And i need any tips abouts...

1. dpi I come from imprent and there only we use 300 dpi and 72 to screen of computer. But now wich the news tablets and smartphones you can read about 150dpi, 160dpi,220dpi and is very crazy.

2. Bit I export my images to 32 bits but now i read that is more important to export in 24 bits O.o

3. Resolution in retina display or another devices. I´m very confused because you can interlenice

4. Resolution Independence. How to work that function of GS?

5. Resize an imagen in GameSalad. It must to be divisible between 4 or 8. But when i export in Illustrator i only create a document of 800x600 in RGB with 72 dpi. Any advice? You work making a document of 64x64 and make all your design there?

6. How can i learn more easy to write english? Is so hard and slow to me

Regards and i hope that my english will evolutionate in that forums.

jamie_c

If you have the option in your version of Illustrator to choose "Save for Web" under the File Menu instead of "Export", use that it will give you more control.

1. You will always want the actual DPI of your images to be 72, never more, never less.

2. The higher the Bit number the larger the file size your image will be. If you can have the same image quality at 8 or 24 Bit instead of 32, choose the lower number. It will reduce the size of your game file and potentially allow your game to run faster. But if the image quality suffers at a lower Bit Depth you may not want to go that route.

3 and 4 You only need to choose Resolution Independence if you are creating a game for iOS. No other platform uses this. This allows your game to function correctly on iOS 7 and any early iOS versions supported by Apple by creating Retina and non-Retina graphics from one set of images.

5. You should create your image source files in Illustrator at the exact pixel dimensions you will need them in GS at 72 dpi. Don't enlarge them in GS, if you do your image quality degrade. When starting a new Illustrator file, set the Artboard Width and Height to the size you'll need your graphics in GS (1024 x 768, 300 x 100, whatever). Then when you "Save for Web" they should be sized correctly.

6. I have no idea, sorry.

Hope this helps a little....

Danjinkies

To add to #5, you can add multiple art boards inside a single Illustrator file using the SHIFT+O key and then resize them to what ever size you need. This way you can work on multiple images in one file with varying sized artboards and then export them using the "save for web" option.

Here's something else that you might find useful: http://www.arcticmill.com/2012/08/export-layers-as-png-files-from-illustrator-in-multiple-resolutions.html
This script will save you some time if you are exporting a large quantity of png images.

Good luck!

Socks

1. You will always want the actual DPI of your images to be 72, never more, never less.

Ultimately the pixel count is what matters, so if you have a 512 x 512 pixel image @ 112 ppi or a 512 x 512 pixel image @ 72 ppi or even 10,000 ppi or 4 ppi they will be the same resolution within GameSalad - the ppi only defines the 'size' GameSalad interprets the images as.

For example let's take our four hypothetical 512 x 512 pixel images, one at 72 ppi, one at 112 ppi, one at 10,000 ppi and one at 4 ppi - if we import all four into GameSalad and put each into a 512 x 512 pixel actor (or 256 x 246 pixel actor for Retina) then all four will be identical, they will be the same size, quality and resolution and use up the same amount of RAM and disk/flash space.

I'd agree with the recommendation to make your images 72 ppi just for convenience, but making them a higher or lower ppi (with a fixed pixel count) doesn't effect anything like quality, resolution or file size, it just means GS 'knows' what size they are, but obviously if you know what size the image is meant to be - and are placing it on an appropriately sized actor - then the ppi is irrelevant.

2. The higher the Bit number the larger the file size your image will be.

Although it's good as a general guideline, I wouldn't say this was always true, higher bit depths can often compress better, especially when they avoid things like noise and dithering often used in 8 bit images - and ultimately both 8 bit and 24 bit images will be held in 24 bit colour space on your iPad or phone so even if you do slim the file down so its disk usage is smaller it will just put that 'weight' straight back on when it's moved into RAM on the target device - and it can even take up more memory when in RAM than the original 24 bit image would have done if the file size reduction software has used dithering of any kind.

If you can have the same image quality at 8 or 24 Bit instead of 32, choose the lower number. It will reduce the size of your game file and potentially allow your game to run faster.

The bit depth of your images won't effect the speed your games runs at, you could argue that an 8 bit image might load faster (but I've not seen anyone conclusively prove this) but once loaded 8 bit and 24 bit files are identical (they are all effectively 24 bit) so a game with 400 8 bit files won't be any faster/smoother than a game with 400 24 bit images.

Sorry to be such a pedant !

8-X :-@ ←me.

jamie_c

Be as particular as you like Mr. Socks, you're a master at it!

I agree with everything you said anyway, my original post was meant for a quick, general understanding of the issues, not a college level class.

Socks

@jamie_c

Be as particular as you like Mr. Socks, you're a master at it!

I agree with everything you said anyway, my original post was meant for a quick, general understanding of the issues, not a college level class.

Lol

Agreed, as a general guide, especially those new to this kind of stuff, sticking to 72 ppi will avoid any confusion when an image is imported into GS and appears to be a weird size.