🔒 Locked

MegaTexturing / ClipMapping

Started by haliop Jun 29, 2010 at 4:37 AM 2 replies 4.7k views

Original Post

Jun 29, 2010 at 4:37 AM

hello all.
im searching for a MegaTexture / Clipmapping for C++ usig DirectX 9

i have tried for too long to understand how to implent it in the open-source project i am at , and after too much time spending on learning i am pretty much exusted from it since it stoped my progress .
im not an expert coder nor i know nothing about directX that is why im after a library or source code to learn from i will also appriciate any help by talking with ppl who made it and will agree if they have some spare time to walk me trough it, it will mean a lot to our project and will be credited .

we are also inviting new people to check out our progress maybe give us feedback or even join in and help us developing a new breed of Game-Engine.

our project is called DOSP - S3GE which stands for DarkGDK Open Source Project - Super 3D Game Engine. this is our Ad/Logo(there is just a bit of Antiallising over the top text that is still a bit of a problem).

http://img818.imageshack.us/img818/1935/s3ge2.png
i am sorry i dont know how to implent the actuall Picture to show on the Thread itself.. so here is a link.

we have a stable SVN of our progress it is pretty amazing.

this is the forum thread on The Game Creator Forum , feel free to cruise it however we still have a lot to work on so dont excpect miricales.
http://forum.thegamecreators.com/?m=forum_view&t=155919&b=22

about this post, i am desperate for any help in MegaTexturing and ClipMapping i know they are a bit diffrent i figured i can use ClipMapping for Terrains and MegaTexturing for 3D Meshes and maybe find a way to combine these 2 and create a new Generation of MegaTexturing , also keep in mind that any help you will give will help everyone else cause it is an open-source and will be able to exctract the MegaTexturing as a Static Library with a Wrapper so other can enjoy it also.

mightypigeon

Jun 29, 2010 at 5:13 AM

If you are implementing virtual texturing (megatextures) there is really no point doing clipmapping as well, they accomplish the same thing. (in fact, Wikipedia considers megatextures to be "actually an implementation of the idea of Clip Mapping")

Anyway, here's the standard resources that explain it all:

id Tech 5 Challenges - good overview of the subject

Sean Barrett's Virtual Textures presentation - pretty much the holy grail of megatexture resources, if you haven't watched his video presentation already do it now. This should explain about everything you need to know. There's demo code too, though it isn't the cleanest, most optimized thing out there. But the concepts are good and the shaders are a good reference to work from.

Brad Blanchard's virtual texturing demo - probably the best example code you are going to find. It's in C# but that shouldn't matter.

JMP van Waveren's publications - Jan is one of the people at id Software working on id tech 5, the papers here aren't directly megatexture related but they are a good reference for later optimizing your streaming with compression.

Other than that, what issues have you been having getting it working?

haliop

Author

haliop

Jun 29, 2010 at 5:49 AM

ive rad most of it.
maybe i'll take a second look at it and maybe a third.
my problems with it , i simply dont understand , im working on a really high end Texture if you looked at the png located in the main post of this thread , you may have seen on the top right , Trixie.

thats one of my jobs in the engine , Trixie is a pretty powerfull tool that lets users Texture Huge Aread but rather then with a few textures blended and tiled across a map it uses up to 256 textures and combine them at the end into 3 , one for diffuse that contains all the blend layers one for normal and one for specular and maybe some more but i havent got that far yet.

currently im texturing with 4096x4096 and with MegaTextures i'll be able to really achive something that is even higher end then Id tech or Crysis engine.
its a photoshop for 3D objects.

about the diffrence between Clipmapping and MegaTextures, well from what i understand ClipMapping is better for terrains and takes much less time to calculate while MegaTexture is better for Static Objects.
its just what i understand but until i'll be able to implent it i wont know for sure.

so the problem is that i simply dont understand it as much as i thought i did i guess. i will take another look at the videos/tutorials/refrences presented by you , maybe the second or third time will work for me.

how come there isnt any Library for it ? as most ppl who are building games that containts terrain will want to use it..

ok ty for your links i will try and try until i'll get it .
however i will walktrought those again and ask questions more accurate then the entire system behind it.
soory about the long post im pretty confused .. :)

scope

Jun 29, 2010 at 9:19 AM

I've implemented virtual texturing in dx 9 and c++.

I have to say that it's not that hard to get it working once you grasped the concept. Took a few days have the system running.

The tough part is to actually make it look good :) That's something i've been workin months on (and still am).

Unfortunately i can't share my code since it was for a job.

But like mightypigeon i also recommend to check out Brad Blanchard's virtual texturing demo, which he provides source codes of. I learned a few things by glimpsing at his shaders. Unlike Sean Barrett's presentation, which i found more confusing than informative. But i have to give Sean credit for giving great support at his forum.

Last but not least, i recommend to settle for a strongly compressed file format (DXT) as soon as possible. You won't be happy with the file size of PNGs for example.

BTW megatexture is perfect for terrain. To be precise, it's the only application where it basically never fails. Unwrapping some complex models is gonna be a little more adventurous :)

Topic Locked

This topic has been locked by a moderator. New replies are not allowed.