DX11 - Volume Rendering - Article Misunderstanding

miguel petersen · 2013-09-10T16:29:32

Hi guys! Again... So I'm trying to follow an article/tutorial on volume rendering from GraphicsRunner (Great!) [ http://graphicsrunner.blogspot.dk/2009/01/volume-rendering-101.html ]. But there is something which I don't understand, which is the following: We could always calculate the intersection of the ray from the eye to the current pixel position with the cube by performing a ray-cube intersection in the shader. But a better and faster way to do this is to render the positions of the front and back facing triangles of the cube to textures. This easily gives us the starting and end positions of the ray, and in the shader we simply sample the textures to find the sampling ray. So I understand that I have to render the back and front culled positions to individual textures, which I am doing and it works (It looks fine), but does he mean render the depth model into view + projected space, or to render it as a texture that can be sampled onto the cube with the cubes respective texture coordinates? Thanks, as always. -MIGI0027

Graphics and GPU Programming Programming DX11

Started by Migi0027 September 06, 2013 01:52 PM

22 comments, last by Migi0027 10 years, 7 months ago

Migi0027

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Author

September 09, 2013 06:33 PM

You seem awfully quiet about this subject, did I do something stupid?

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Styves

1,811

September 09, 2013 09:00 PM

A few things:

What format is your back/front textures? If it's 8bit you should scale to 0-1 range for output (if you're using HDR values then you should be fine).
Your position should be in texture space. That is, bias and scale it from [-1, 1] to [0, 1] (pos * 0.5 + 0.5) when you read your texture.