Tutorial 11 :: Finishing our Culling, Complete Octree Funcionality

[mikeschuld]

Tutorial 11 discussion

[gonZoX]

Hy, first let me thank you for your very good series of tutorials, I like them very much.

Just one question about the performance of the engine so far :

I just added a simple frame counter to show me the framerate in the window.title and when I zoom out of the scene so that there are for example about 300 teapots, the fps rate went down to 15 or less ...

OK, I'm working with a notebook with X700 gpu, that is not the fastest, I now, but breaking down the fps rate so much only by drawing this amount of static objects, is this normal or do we waste to much resources by the way the engine works in this example ?

cu,gonZoX.

P.S. Can't wait for the next tutorial, hope it will be here soon

[Chr0n1x]

Hmm, im getting 37 FPS on 500 teapots with a RADEON 9800XT.
It may be your memory or CPU, what are they?
Mine is a P4 3.0Ghz HT and 1.75Gb ram for reference.
(Note this is my slower computer , but from this the performance seems to be fine)

[gonZoX]

I hope it's only caused by my slow laptop. ( AMD Turion MT30, 1GB ram, ATI Mobility Radeon X700 512 MB (shared memory)).
But until AMD hasen't released a better mobility processor, I won't spend the money for a new notebook
I just will do a test with 3dmark 2006 to compare the fps rates and let you know the results.
(But even my good old notebook isn't a gaming machine at all, I think 15 fps for this relativly simple coding example are to less)

cu,gonZoX.

EDIT : shame on me !!! (or better : on my notebook , after running 3dmark I'm shure what is this problem ...)
And before you ask : NO, i wouldn't publish the 3dmark score of my lame system.

[mikeschuld]

I get a straight 60 fps with 500 teapots as long as I'm not also drawing the octree lines. Of course I am running 2.5 GB DDR400, AMD Athlon X2 4400+ on a Radeon X1900XTX, sooooo.... that's not much of a basis for comparison. :/

[ericc59]

With 500 teapots drawn in debug mode without the lines I get about 50 fps on a Pentium D 945, 1gig DDR2 800mhz memory, and GF 6600.

[Chr0n1x]

Oh yeah sorry forgot to mention, Octree lines enabled in Debug mode.
I wanted to keep it as slow as possible to see how low itd go.

[trekker]

Hi,

Here is a class diagram of Tutorial 11 if anyone is interested.

http://www.petragames.com/HMClassDiagramTutorial11_.pdf

Great tutorials and site!

-trekker

[mikeschuld]

Thanks! What tool did you use to generate this?

[trekker]

I used Visual Studio 2005.  I just created a new empty project, added all of your tutorial files to the project and told it to create a class diagram.

The "hardest" part was to arrange the classes together in a way that made sense, and arrange in a way that fits nicely on a 11x17 printout.

-trekker

[Chr0n1x]

Nice job arranging those things, that looks like you put a bit of work into the arrangement.
Makes you really appreciate how big its gotten.

[Arkcann]

I've been having a really annoying problem with my octree, for some odd reason whenever I zoom out of the boundary of the main octree node (the largest one), it stops rendering everything, I no longer see the red node lines nor do I see my models. I've downloaded the example, and I haven't been able to find any difference between mine and your code except that I'm not rendering 500 teapots, only 2 models (I was doing more but I kept lowering the number to see what the problem was), one of the models is a quad and one is the skull model from a previous tutorial. I don't think either of these are the problem, if screenshots would help anyone better understand this problem then I'd be glad to get some up later on, thanks for any help.

edit: Also, it seems that everything renders whenever I'm zooming in or out by pressing the left and right mouse buttons respectively, maybe that'll give someone a better idea of whats going on.

[Nemo Krad]

Could this be due to the min,max depth of your viewport object in the camera class??

[Arkcann]

Hmm.. That would make sense except that everything is drawn even when I'm zooming out, which if it was due to the min and max depth it shouldn't draw if I'm outside the max depth at all. Perhaps I'm misunderstanding what min and max depth does but from what I understand if you are within the min depth it won't draw and if you're over the max depth it won't draw. Sigh, sorry for the sort of hard to understand post, I'm at school and am pressed for time so I can't elaborate more.

edit: Wow, the problem has been solved, in my Camera update() method I reset my camera frustum before I reset my world, view, and projection matrixes, moving the camera bounding frustum code beneath that code fixed the problems I'd been having, odd how the position of a line of code can have such a large effect  , thanks for everyones help though!

[DevlinSE]

How do I keep object from being culled like a skybox for instance?