Interpolation

[LiquidIce]

Is it possible in Direct X 8.1 ?
If so how ?

[LP]

What do you mean by interpolation specifically? You can do texture interpolation, but I'm not sure that's what you are asking for...

[LiquidIce]

What do you mean by interpolation specifically? You can do texture interpolation, but I'm not sure that's what you are asking for...

For example, in SNES they use like Kreed's Super2x Sal .

Here is a screen shot without interpolation:
http://www.aotaonline.com/nointerpolation.gif

And here is one with it:
http://www.aotaonline.com/interpolation.gif

I saw something like it when resizing DX surface (image gets stretched), but it is not quite of what I am looking for.

[savage]

I could be wrong, but are you looking for anti-aliasing routines?

[Clootie]

It's not clear from images you have proveded (because of color quantization in GIF format), but seems what it's linear filtering of lower resolution image to higher resolution screen. And it can be done with DirectDraw by stretching and in Direct3D by providing enlarged desting rect during Present (or by using render to texture technique for advanced processing).

[Paulius]

2xSAI is a very cool algorythm which doubles the size of the image and interpolates it(calculates mising pixels) through special line and edge detection rutines which make it less blurry compared to simple bilinear filtering. Check out its creators homepage http://elektron.its.tudelft.nl/~dalikifa/. It's great for emulators which emulate low resolution consoles, but is a bit slow and i have no idea why would you want to use it for something else. It has nothing to do with directx, but you could implement it by hand.