how many polys?

Blitz3D Forums/Blitz3D Programming/how many polys?

Bouncer

(Posted 2003) [#1]

I know that this issue has been covered before... but I'll ask anyway.

How many polys do you think I can safely use with my game if my minimum target machine will be about 500Mhz-800Mhz comp with GF2.

The objects are pretty small on the screen... so fillrate is not so much an issue.

Would 8,000 - 10,000 be to much?

Rob	(Posted 2003) [#2]

I have a similar spec. If you limit the surfaces you can probably get away with that amount 8,000 to 10,000 pretty well.

Gabriel

(Posted 2003) [#3]

It's much more about surfaces than polys. I wrote a little tech demo ages ago which ran at 85fps ( refresh rate, so it might have been more ) on a gf2mx and had 30,000 polys. But only five or six surfaces.

I have an actual game I wrote which uses no more than 3,000 polys and it runs at only 30-40fps on the gf2mx, because there are anything up to 100 surfaces. If you can find the balance between polys and surface, 10,000 sounds fine, but if you can't keep the surface count down, you might have to go lower.

QuickSilva

(Posted 2003) [#4]

Any chance of seeing that tech demo with the 30,000 polys in action as I cannot get near that figure even with my Geforce4 Ti4600.

Jason.

Ross C

(Posted 2003) [#5]

Graphics3D 800,600
SetBuffer BackBuffer()

camera=CreateCamera()
PositionEntity camera,0,0,-10

light=CreateLight()


s=CreateSphere(44)
s1=CreateSphere(44)
s2=CreateSphere(44)

PositionEntity s,-2,0,0
PositionEntity s1,2,0,0
PositionEntity s1,0,2,0

While Not KeyHit(1)


	If MilliSecs()<timer+1000 Then
								frame=frame+1
	Else
								fps=frame
								frame=0
								timer=MilliSecs()
	End If
	UpdateWorld
	RenderWorld
	Text 0,0,"FPS="+fps+" polys="+TrisRendered()
	Flip
Wend
End

Rhyolite

(Posted 2003) [#6]

Yikes, I thought I was beginning to understand 3D but I have obviously missed something crucial here! I thought frames per second was all about number of polys but from what you are saying and after running the code above its obviously not!!

I don't particualrly want to hijack this thread so could someone direct me to another thread or article on this subject? Or perhaps that what this thread is about??

BTW, if its any help for judging your spec, by setting FLIP FALSE in above code i get 400 FPS with XP 2400 and Geforce 3 (above your minimum spec I know but might help).

Rhy

Bouncer

(Posted 2003) [#7]

There's lots of stuff to consider when wanting to maxsimise framerate in 3D.

Polycount, texture resolution, surface count, fillrate etc...

But the purpose of this thread was just to know the normal amount of polys a GFX card like GF2 can push easily. I have my surfaces minimized already, but as I have Radeon 9600 I have only some Idea how much polys a card like GF2 can cope with.

Zmatrix

(Posted 2003) [#8]

10,000 polys@60+fps shouldnt be a problem on gf2
its throughput under dx7 is around 12-15 million tri's per second.(according to nvidia's specs)
(thats probably single surface)

In the game im working on at the moment, the average arena is only about 5000-8000 poly and it still runs at average of 20 fps on a 233 and a voodoo banshee.(not great ..but it runs it)

Zmatrix

Rob	(Posted 2003) [#9]

Surfaces in blitz are really directx state changes I think.

Mustang

(Posted 2003) [#10]

It's all about balancing the content... using enough, but not too much, and knowing the basic mechanisms of real-time 3D tech. Tricky part is that the rendering requirements changes every frame (usually) and you have to prepare for that too. There is NO automagic way to do this as it is highly dependant about many things, including your coding.

All those things Bouncer said are important, but only experience will get you the "gut feeling" how much is too much...

Bit like F1-driver if you want an example; no matter how talented, fast and eager you are; you won't win any races until you learn to tune the car for maximum performance. :)

Rhyolite

(Posted 2003) [#11]

I know this is Bouncers thread (sorry again) but thanks for some of those explanations. I had a play about last night creating my own polys and surfaces using B3D commands (up until now had only used modelling apps). This was really cool and has really opened my eyes to yet more 3D stuff. This is such a fascinating area I cant stop messing and am a complete 3D junkie now!!

Oh, and while I am waffling, a big thanks to the community for all the help it has given me getting started. I have spent hours (no, days!) reading through forum posts and articles since I started 'messing' with 3D. Cheers :o)

Rhyo

Ross C

(Posted 2003) [#12]

Pleasure to help (if i did) :)