Volume Render

[giado]

I'm right now approccing OpenGL and I do not understand how can I render an image stack. I have find a lot of example that show how to build a cube and attach an image to every face of the cube, but I haven't found any example on how to put different slice inside the cube and then render the cube as a volume.
Can anybody help me ?

[forth]

What you need is a 3D texture. It works like a standart 2D texture, but, for example you must define 3 texture coordinates for each vertex - (x, y, z) or (s, t, r) as you like.
3D textures can be usefull, for example, in medicine, to view the internal structure of a body without actually slicing it.
The usage depends on what do you need exactly. What kind of application are you writing?

[paintor]

Hi,

there are a variety of differing approaches to volume rendering on the gpu, it depends on your target hardware. if you want it to work on most modern hardware then a bunch of slices being textured by volume information from a three dimentional texture is the best approach. Several papers have been written on the subject if you wish to study each different method.

here is a good start: there are some references in this paper to chase around. also looking up the institution that did this paper is a good idea

<a href="http://www.vis.uni-stuttgart.de/eng/research/pub/pub2001/GH2001.pdf" target="_blank">
Pre-integrated volume rendering paper</a>

there is also an open source project on sourceforge that concentrates on some recent volume rendering algoritms on modern gpus

OpenQVIS

hope this can be of some help

[Silkut]

There is some explainations on OpenGL RedBook, isn't it ?

[giado]

Originally posted by forth:
What you need is a 3D texture. It works like a standart 2D texture, but, for example you must define 3 texture coordinates for each vertex - (x, y, z) or (s, t, r) as you like.
3D textures can be usefull, for example, in medicine, to view the internal structure of a body without actually slicing it.
The usage depends on what do you need exactly. What kind of application are you writing?

Thank you very much for your suggestion. I would like to write an application very similat to one that you can use to view MR o CT images. I would like also to add funciont to display the max or min projection or a blend projection. I don't need a sofisticated software but just a viewer where I can load the image stack render it in real time during rotation and so on