Software Rendering, Part IV: Shading and Filling

Software Rendering School, Part IV: Shading and Filling
Author: Mihail Ivanchev, Hans Thörnquist
Description: This article briefly discusses depth sorting, gouraud shading, phong shading, and filling using a software renderer. Sample source code is included.

LoL, nice job Apex, never expected it will actually look so cool in it's edited variant but it really does! Thanks for making an article from my rude notes!

Anyway just wanted to say some words about the 'next' article, which is done and only should be edited by Hans. I'm working on the source right now and it should be done soon but since i'm leaving for Germany this Monday for a week it won't be released untill after 29+.06.

The article explains clipping in detail and is some kind of clipopedia. It is also absolutely HUGE in size - 11 pages in A4 format ).

Some basic info to get you heated up :P - I discuss general clipping algorithms and explain the homogeneous clipping in detail so that everyone will be able to understand it - not like those complex documents on the net about it.

Well that's it! Hope you're actually reading my articles )

Is there a good reason that only I shall edit your next tutorial? Perhaps you'd rather say that over ICQ

Anyway, I'd just like to point out that Mihail figures out and writes the articles, I'm just the proof-reader sort of. I don't know when I will write an article in this series myself, if I get any bright ideas then I will. And if I'm willing to find some time to spare of course...

When is part V coming? Some of us are waiting for it to continue our work :wink:
Don't keep them waiting to long

Hey Yukito, 10x for the comment, i was getting the feeling that i write articles only for myself and coelurus here...

But now i'm sure it's not for nothing so i'll just prepare the next article and release it even if i don't have demos for it for the time beeing!

Hope it's better than keeping my audience waiting )

Oh, and if someone is willing to help us with source, please!!! You're more than welcome!

I have implemented texturing in your source, if that could help.

Yes, i would gladly see your work! Just send it over to mihail1212 at gmail dot com. Problem with that renderer is, that it's not very extensible. I should either think of somethin' smart, or just write new one!

10x for the help! I'll write an article 'bout texture mapping real soon, and if most likely include your work

When I said your source, I meant the rasterizing code only. I threw together a small framework in ~30 minutes. It is ugly, but it works. The texturing stuff could easily be extracted from the code, and stuffed in to whatever you would write.

Yes, i would really like to see it!

I tried to send the code, but the MAILER-DAEMON@yahoo.com says the remote host said: '552 Illegal Attachment' and the the message had been truncated to 5K.

Don't know what to do about this?!?

Do you another place I can send it?

dunno where you've tried to send it but try with one of these two:

mihail1212 AT yahoo DOT co DOT uk
mihail1212 AT gmail DOT com

Sending it now...

Hi there, thank you for writing this articles about software rendering i've got a gp2x game device with linux, it's a great device with 2 arm processors but it hasn't fpu, the only functional 3d engine we can use is a commercial one that only uses one processor and floating point arithmetics. Your articles have shown me how 3d graphics work so now I can start doing 3d stuff using fixed point arithmetics and the second processor

I'd be very happy if you go on with the next articles lighting and texture mapping would be great! :P

Thanks for your articles

Originally Posted by oyzzo

Hi there, thank you for writing this articles about software rendering i've got a gp2x game device with linux, it's a great device with 2 arm processors but it hasn't fpu, the only functional 3d engine we can use is a commercial one that only uses one processor and floating point arithmetics. Your articles have shown me how 3d graphics work so now I can start doing 3d stuff using fixed point arithmetics and the second processor

I'd be very happy if you go on with the next articles lighting and texture mapping would be great! :P

Thanks for your articles

A GP2X you say? I always loved those devices!!! Back to the topic, to be honest, I didn't see future for them for quite a long time, but I'm now at the university studing CS and from a month or two, I'm quite motivated to continue with them. I even has a plan, what follows. Next article will deal with the last nasty thing: clipping (mathematicaly complex) and the tutorials after that will concentrate on the interesting topics as lighting and texturing and more So stay tuned on the frequency, you haven't saw everything yet.

P.S.

Btw, I heard somebody has an idea to write FPM articles for DevMaster. I would like to know what happened with that project?

Great! I'll stay tunned

Before reading your tuts I thought 3d programming was tedious and boring, but now i see it's amazing and funny :P i spend long times coding and testing stuff, actually i'm learning a lot thanks to your tuts they're easy and clear enough to give a basic understanding of the matter and makes you want to learn more.

Good job guys!

can some one explain how the code in tutorial 4 under the comment:
// find if the major edge is left or right aligned

works?

Yes, I can explain it

The major edge is in the context of the code simply the _longest_ edge of the triangle. Perhaps you also want to know, what's the deal with it? We need to find, whether it's left or right aligned, so we can decide, in which half-plane the other two edges of the triangle will be in. Without this knowledge, calculations will be wrong in about 50% of the cases. Using this information, we can quickly rasterize the polygon, since we know, which edge we can slope on, without stopping.

Hope that helps, if it doesn't - PM me or post something here!