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Member Since 16 Dec 2012
Offline Last Active Jun 01 2015 02:11 PM

Posts I've Made

In Topic: Tutorial From RasterTek, Question about Down Sampling

08 October 2014 - 04:53 PM

uh... you don't really give us a lot to go on. What exactly are you trying to do? What is the problem you're experiencing?


From what I can tell, it looks like you're trying to create a screen shot texture of the current window and are rendering it as a quad. You say something about blurring, though it looks like you're doing it manually?

One option is to take a screenshot of the current buffer, apply it to a texture, and then scale the texture down. This has the downside in that it consumes a lot more video memory, but does the blurring on the graphics card.

The other option is to dynamically create a smaller texture. The process is similar to the method above, but you'd want to apply "super sampling" to your original scene based on the resolution of your target texture size. You pretty much map a pixel from your target texture to your original scene. If the target resolution is smaller than the original scene, you should have overlap of more than one pixel from the original scene. You take the collection of these overlapped pixels and average all of the RGB values into a final pixel color result. This is done manually on the CPU, so it can be a bit more expensive.

Hi, sorry, I will make sense about it.


I try to scale the texture down, but the result of the texture were looked weird. I used a smaller texture ( screenwidth / 2, screenheight / 2 ) for scaling down. but finally ,I got 1 of 4 , a part of original texture (I mean I got only left-top part of the original texture, not the whole scene). I don't know how to fix it in DirectX 11, because the scaling down procedure was totally handled by DirectX.

In Topic: Question About Fluid simulation

24 June 2013 - 12:39 PM

Rendering and shading fluids is definitely tricky, but if course it very much depends on how you computed them in the first place.

If you have a eulerian grid which you used to compute motion by diffusing and advecting velocities / temperatures / densities / colours, you can pretty easily ray trace through the volume and get some decent results, depending on the resolution of your grid.


If you went down the sph / mass particles way, I find it trickier. Depending on what kind of fluid you are trying to render, you could render multiple times, to get surface depth and thickness, and then composite together. 

Or you could try sorting them and alpha blending them. Of you could try bucketing them into screen tiles/cluters and evaluating each block to reconstruct your surface. Marching cubes could be an option?

You mean that different fluids, like difference between ocean and a cup of water, will be simulated in different methods( I think maybe it's just a something detail in equation's item, is that right ?) ? I'm stopped at surface-reconstruction, that's very hard to me. I try to read a lot of opensource and thesis, then I can do next.

In Topic: Question About Fluid simulation

24 June 2013 - 12:32 PM

This is the guy responsible for the most gorgeous fluid effects in films:


Also check out his lighthouse video:


Thank you, I already had saved his site

In Topic: Tangent Binormal Normal

13 June 2013 - 11:47 AM

Oh, guys, thank you all !


I think I've remind the reason about that, I read the old book just now, and the 1st chapter is about physical wave. There is information about tangent & binormal theory.


Book - GPU Gem 1 By nVIDIA

In Topic: About water refraction

25 April 2013 - 01:38 AM

Can anyone help me please ?


1. Why I need to calculate refraction & reflection vector ? Use reflection & refraction render texture for water plane will contribute some visual error ?


2. I debugged today, and another problem here, the whole water plane rocked when I turn my camera, I always feel that the surface of the water there is a delay. ( It means the water plane will dislocated with the bath. )