Allocate memory in GPU, flash/air

Question

This is more an "implementation" of technology kind of question.

In old times, when I worked with C language, you could specify to use VGA memory or ram memory for allocation of bitmaps structures, then you could work with them a lot faster.

Now we are in 2013, I create bitmap in AS3, and it is allocated in ram (I've seen no option to use the GPU and 100% of cases im sure it is using the RAM, because it increases exactly the expected bitmap size.

¿Is there any option to use GPU memory?

Thanks

Answer 1

Check out the API docs for flash.display3D.Texture - there are 3 methods:

uploadCompressedTextureFromByteArray(data:ByteArray, byteArrayOffset:uint, async:Boolean = false):void
Uploads a compressed texture in Adobe Texture Format (ATF) from a ByteArray object.

uploadFromBitmapData(source:BitmapData, miplevel:uint = 0):void
Uploads a texture from a BitmapData object.

uploadFromByteArray(data:ByteArray, byteArrayOffset:uint, miplevel:uint = 0):void
Uploads a texture from a ByteArray.

So you can't allocate the memory directly in the GPU. You must upload data from a ByteArray or BitmapData, which first exists in RAM. However, to minimize CPU RAM usage, you could potentially reuse a single ByteArray or BitmapData in RAM, change its contents, and upload it many times, or release it after loading. But you can't access the contents of GPU memory directly, as far as I know.

As far as "read access", the only way to get data back from the GPU memory (again, a slow workaround) is to draw the Context3D back into a BitmapData via Context3D.drawToBitmapData... basically like a screen grab. The Starling Framework has an example of this functionality via Stage.drawToBitmapData.

Basically, the Stage3D APIs weren't setup so you can easily access the GPU memory.

Answer 2

You cannot allocate GPU memory manually like in other languages, but you can indeed accelerate your graphics using the GPU with different Adobe technologies.

For example if you want GPU accelerated video decoding you should be using StageVideo, or if you want to accelerate 2d or 3d graphics you could use Stage3D.

Unless you want to work in a low level fashion with Stage3D, it is recommended you use an intermediary framework.

For 2d the best solution is by far Starling. It is a solid framework endorsed by Adobe which has been used in countless commercial projects and is constantly optimised.

As for 3d take a look at Flare3D or Away3D.