Archives for: July 2008

2008-07-30

Permalink 17:44:17, Kategorien: CloudSystem  

Debug and integration

Hi!

The last few days I worked to get the plugin running. Now it does. I made also several changes on the interface. After the plugin was finally running, I made some first performance tests and debugged all SERIOUS problems (no crashing anymore ;-)). Physical problems I'll be first able to detect, when I've written some rendering methods, to watch the cloud evolution itself.

After now, I'm going to check out all the rendering stuff. So till then ;-)

2008-07-28

Permalink 21:07:29, Categories: Project Details  

A trip to the movies

This is a video of the ocean mesh in its current state: ocean-prelim.mpg (Note: You might have to right click and "Save Target As")

Things to do:
* Reflection/refraction
* Figure out a way to calculate normals based on wave equations
* Perspective corrected texture mapping for the normal map far away
* Get better video recording software/converters for Mac OS X

-Pavel

2008-07-25

Permalink 12:55:42, Kategorien: CloudSystem  

Cloud dynamics at a good point

Hi!

This week I worked very intensly on cloud dynamics. I could improve it further I initially expected. By now all main-methods and functionallities are implemented, but not tested yet. Now I want to figure out the best way for debugging a simulation. I think a graphical approach would be the best in this case, but we'll see...

Permalink 07:33:51, Categories: Project Details, Progress  

Oceanography

The past few weeks I've been experimenting different ways to get the little quad of water mesh I had into an ocean. My initial approach was to implement some sort of geometry as described in this paper, but I ran into a good number of problems. First off, after constructing the near patch, it wasn't too easy to integrate it into CS with a moving camera. I had to index the texture and wave generation coordinates in world space from the shaders, and that sometimes had bad effects. Also, the far patch gave me a number of problems, most of which was that it was almost impossible to find the correct transform to paste it in front of the camera. I'm not too sure how the conics in the paper mentioned above would have proved useful.

So, I decided on a new approach. A better approach. I got my idea from this paper, which employed the use of different ocean "cells," each with their own geometry. This way I was able to do some LOD calculation at the same time as I was generating the ocean waves. Since the wave generation is still based on world-space coordinates, it was easy to tile the cells and maintain a seamless ocean surface. Currently the only problem with this approach is that the texture coordinates are not accurately being set so there is noticeable "popping" when you move the camera up away from the ocean because you can see the different texture coordinates changing. I hope to get that fixed over the weekend.

-Pavel

2008-07-22

Permalink 10:20:29, Kategorien: CloudSystem  

Work is going on!

Hi!

Yesterday I finally got the msvcgen run due to help of res, xordan, brandano and vknecht.
Afterwards I immediatly started with implementation. After some initial issues I got the existing code running and extended it.
Currently am working on various aspects of the cloud-dynamics. The basic construct is already coded, now I take care of some calculus-functions and other helper methods which are needed by the simulation.

2008-07-05

Permalink 23:45:33, Categories: Project Details  

Fresnel articulation

So, after reading about tangent space and realizing that my normal maps were in it, I figured out where my lighting equations were going wrong. Consequently I was able to put all the necessary vectors into tangent space to do my lighting equations, and now we have a water that has a proper (approximated) Fresnel term and goes translucent at the correct angles, as can be seen here.

-Pavel

2008-07-04

Permalink 17:51:21, Categories: Project Details  

Water you up to?

Hello, everyone.

I've been working on adding a water mesh plugin to CS for the past month, and I haven't really been letting the community keep up with my progress. So, I'd like to tell you all what I've done so far!

First, I started to build off of the protomesh plugin that's already in CS. This gave me a great framework for having a general factory with all of the necessary information: vertex locations, color, normals, etc. The great thing about the protomesh is that it doesn't have too much clutter in the code so it was relatively simple to figure out how everything worked with SCF and implementation details. Hence, it was fairly easy to get *some* sort of mesh going, and the next step would be to add water-like attributes to it.

This is where things started getting tricky since this is my first time doing a water effect and I had to do a lot of reading regarding reflection, refraction, Fresnel values, wave generation, fluid dynamics, etc. Finally, after I settled on this paper, I started learning about the shader system in CS.

In my Graphics course here at the University of Chicago, the term "shader" was used to mean the vertex and fragment programs that are loaded for the specific rendering step. Unfortunately this created a bit of confusion when reading the documentation for shaders in CS, so it wasn't immediately obvious how everything worked. It wasn't too long, however, until I finally realized how to define shader variables, add shader programs, and generally define a mechanism for rendering a simple water mesh.

So, with the help of sueastside, I got some ideas (and normal maps) to create a preliminary water effect. Unfortunately, after reading a few different methods for looking up or approximating the Fresnel value, it isn't terribly clear what the best way to go about implementing it in CS is. I have a few ideas that involve tactics from the aforementioned paper, but I want to have a working version of everything before I start making it all better.

So, I present to you what I have so far in the form of screen shots (or you can go check out my SVN branch). These are using the same hard coded directional light with different normal maps. =)

-Pavel

2008-07-03

Permalink 11:50:07, Kategorien: CloudSystem  

API put down

So... Since I've many exams right now, I didn't had much time to work, but I was able to steal a little bit and I put down the first Interfaces for the cloud system

July 2008
Mon Tue Wed Thu Fri Sat Sun
 << < Current> >>
  1 2 3 4 5 6
7 8 9 10 11 12 13
14 15 16 17 18 19 20
21 22 23 24 25 26 27
28 29 30 31      

Blog All Title

This is the long description for the blog named 'Blog All'.

This blog (blog #1) is actually a very special blog! It automatically aggregates all posts from all other blogs. This allows you to easily track everything that is posted on this system. You can hide this blog from the public by unchecking 'Include in public blog list' in the blogs admin.

Search

Misc

XML Feeds

What is this?

powered by
b2evolution