Best image filetype?

street89

Hi guys, Sorry if this has been asked before. (I did a search on here and Google but couldn't find an answer.

What's the correct filetype to use for game textures? From the searches I read, Targa was the one to use but it didn't really explain why. Could someone explain what the difference is between using that and jpeg?

commander_keen

Targa is used a lot because its a simple uncompressed format so its easy to create a loader and of course you dont get any compression artifacts. PSD is more commonly becoming used now which is great because it gets rid of the export process, and afaik its pretty simple to load the flattened data from the file.

In most engines these days a game build wont ship with these common types of files though. Its likely that the engine will save gpu compressed data because applying compression at runtime is too slow, and it will also saves disk space and data read time.

cptSwing

basically just don't use jpg.

street89

Both great answers! Thanks

Dataday

Agree, stick with TGA (Targa), you cant go wrong.

Ace-Angel

Most engines support TGA most of the time, while very few really support JPG, and many others are taking out the JPG support.

Also, as Keen sad, many more take PSD nowadays and do their magic during import/save time. Saves alot of time in bulk.

passerby

targa or psd.

since i work on my diffuse, spec, and normal map all in 1 psd i dont save as psd for the game, instead of got a script called vtools with 1 key press exports out my different layer groups out as separate targa files.

Computron

Do any of these formats indicate wether there needs to be Gamma corection? Is this always done manually?

Justin Meisse

Typically the end result is a DDS file - some engines & pipelines just handle the conversion to DDS for you.

cptSwing

passerby wrote: »

targa or psd.

since i work on my diffuse, spec, and normal map all in 1 psd i dont save as psd for the game, instead of got a script called vtools with 1 key press exports out my different layer groups out as separate targa files.

same here.. my files get so friggin huge that having max or the game engine reload a psd takes way too long. qSave and a page-long photoshop action (adding edge padding and what not) are the way to go for me.

commander_keen

The complexity of a PSD file has no effect how long it takes to load the flattened data. Max does try to show you layer previews even if you dont want it to which makes it slow on larger files, but for a game engine the file size shouldnt matter.

tristamus

qSave is the bomb - saves a lot of time in the long run!

Ace-Angel

Computron wrote: »

Do any of these formats indicate wether there needs to be Gamma corection? Is this always done manually?

The engine during import should do the magic, although in certain cases, it's the shader which can be the problem.

Computron

Ace-Angel wrote: »

The engine during import should do the magic, although in certain cases, it's the shader which can be the problem.

Ok, so targa and .PSD have the necessary meta-data to indicate whether gamma correction is necessary? If I batch import into UDK and click 'OK to All' will it import automatically with correct gamma per file? I wish it could detect normal maps as well based on color and set the correct settings.

commander_keen

Why would any texture be gamma corrected? Textures are authored in gamma space so they should never be corrected.

Ashaman73

For image processing data loss free image formats are best. TGA is simple, but in its standard, uncompressed version , use up lot of space. An good alternative is png when you need compression without data loss (thought you're able to compress pngs like jpeg with loss of data, if you want). Btw. png is able to hold the gamma value of the image.