Novaleaf Technical Diary

XNA 4.0 Performance Considerations

Mon, 02 Aug 2010 00:00:44 +0700

A few days ago I stumbled upon an excellent talk by Shawn Hargreaves at Mix10. You can view it online, or download a high-def version of the video and PPT slide deck from here.

If you like what you see, you can get the demo Shawn shows from here.

So that said, a few points of my own to add:

WP7 does not support unsafe. this takes away a lot of CPU optimizations that you could do on PC and XB360
WP7 apps will support 512mb of ram use, so better to precalculate and use more ram
XB360’s GC will take aprox 14ms to inspect 100,000 objects. We better bet that WP7 will take longer.

VS2010: IDE performance is laggy (how to improve)

Thu, 29 Jul 2010 00:00:45 +0700

I’ve seen some sluggish performance in the VS2010 ide, and thought i’d share how i improved performance:

Go to Tools —> Options drop-down menu
Click Environment —> General from the list
in the VisualExperience box:
Uncheck “Automatically adjust visual experience based on client performance”
Uncheck “Enable rich client visual experience”.
Press OK then restart visual studio.

That doesnt seem to make everything super fast, but it does help make it not-so-slow =D

-JasonS

free ebook: D3D 10

Mon, 26 Jul 2010 11:34:36 +0700

a free ebook on dx10 stuff by some of the big guys in shader books:

http://wiki.gamedev.net/index.php/D3DBook:Book_Cover

game design: agression

Sat, 24 Jul 2010 15:48:35 +0700

interesting link on winning/loosing in games

http://www.lostgarden.com/2009/11/testosterone-and-competitive-play.html

vs2010 resources

Wed, 21 Jul 2010 17:37:44 +0700

here’s some resources i gathered on visual studio 2010 (new features + tricks)

VS 2010 debugger improvements
VS 2010 Pro Power Tools (need pro or higher to use)
10 cool things you didn’t know about vs 2010
Debugging with Intellitrace (ultimate only)
More details on Intellitrace

moving to xna4

Sat, 17 Jul 2010 09:55:12 +0700

Now that the Xna4 Beta is out, our team decided to take the plunge.

A few things to be aware of

Xna4 is VS2010 only.
but xna4+vs2010 can live side-by-side xna3.1+vs2008
Xna4CTP uninstall is a PoS (broken)
use the XNA Game Studio cleanup tool if you run into problems uninstalling any version of XNA. (you will)
Resharper 4.5 does not work on VS2010
upgrade to 5.0!
Resharper 5.0 doesnt really work on VS2008
a lot of key commands are broken :(
XNA4 contains breaking changes.
especially in rendering. hope you like refactoring.

Now is an ideal time to upgrade:

we are rewriting our rendering system, so best to do this as part of our shift to xna4, especially looking at a “fixed function fallback” system.

We already did some tests to make sure our code isnt a nightmare to port, so good times.

-JasonS

critical section perf trick: reducing casts

Wed, 14 Jul 2010 03:36:43 +0700

If you’ve ever had to do something like this:

if(someObject is MyType)
{
var myClass = someObject as MyType;
myClass.DoStuff();
}

then give this a try in critical (perf) sections instead:

var myClass = someObject as MyType;
if(myClass!=null)
{
myClass.DoStuff();
}

it reduces your cast operations to 1 instead of two, and offers similar readability.

enjoys

-JasonS

incremental redesign of Novaleaf Engine

Mon, 12 Jul 2010 08:57:42 +0700

we are about 2/3 through our post e3 “fix up” month, and thought i’d share a tiny bit on what we are doing:

What was wrong with our E3 demo:

The e3 demo was pretty, but had some technical issues:

world objects were atomic only:
this means buildings were a single, opaque object. not because we only support atomic objects, but I didn’t want to spend time finishing the implemenation of composite objects until we were sure about the entire workflow, which leads to:
the game object system was not extensible:
our “Element” system (atomic and composite) was high performance, but extending it was not easy: a single manager class that needed to be extended as a monolithic singleton. not good for supporting various game object categories.
the visualization system was a nightmare:
well not a nightmare really, the system worked, but was overly complex architecture, plus difficult to extend. We have a deferred rendering pipeline, and the rendering system was designed with only that in mind. So extending rendering for use with particles, etc was difficult.
rendering suffered performance issues:
CPU stalls waiting for the GPU, plus mysterious cpu spikes of up to 30ms shows significant risk in the current rendering architecture
misc system design issues:
the particle system and physics system were fairly poorly designed (lacked required features) and need some architecture changes

Tomorrow, I’ll start talking about the steps we are taking to resolve these issues.

-JasonS

.Net SortedSet is almost awesome

Sun, 11 Jul 2010 08:57:43 +0700

I’m working on rendering infrastructure right now, and came up with an idea for how to store and sort renderPackets based on criteria efficiently using a binary heap.

What’s the BCL got?

That’s great, but I remembered seeing an MSDN article on a new BCL collection called SortedSet

Nice features

It’s pretty sweet. As this CodeProject article describes, it has a neat Sub-Tree filter that can be used to partition the view, and it has good CPU performance with O(LogN) time.

Not good enough

Unfortunately, it seems like the BCL team is lapsing a bit on QC: SortedSet is implemented using classes for Nodes, not structs. This has massive, harmfull, repercussions on CF.NET, and therefore makes SortedSet unusable for a core, high-performance game system.

What’s to be done?

Thankfully, I can salvage the goodness of SortedSet’s features by implementing my own version of the class using a struct Node[] array as storage. It’ll take a little time, but I can use the BCL API’s as reference, and that will give me a SortedSet that offers good CPU and GC performance.

-JasonS

Everything you ever wanted to know about CF.NET performance

Sat, 10 Jul 2010 08:56:42 +0700

These are the holy scriptures of CF.NET performance,

specifically written for XNA’s XBOX360 CF.NET implementation 3 years ago, those people doing WP7 development should be able to learn extremely useful perf tuning tricks from these:

-JasonS

my thoughts on scenegraphs

Fri, 09 Jul 2010 08:55:43 +0700

Some posts on how to use or not use scenegraphs got me to write up a little on how we use them:

we use a spatial query for game objects, but a composite object (such as a building) may be made of sub-objects, so i basically have a scenegraph for those.

this also lets a composite objects manage their own collision resolutions, extending the base functionality where needed.

so a hybrid approach!

- JasonS

.net 4.0 "ElasticObject" (dynamic duck typing)

Thu, 08 Jul 2010 08:51:44 +0700

I came across something nice for .net 4.0, potentially scripting functionality

http://amazedsaint.blogspot.com/2010/02/introducing-elasticobject-for-net-40.html

Elastic Object offers a nice way to define/edit xml via duck typing, which may be useful for user-specificed data formats.

keeping it in mind, but unfortunately compiler services are not part of the CF framework, so this long-term usefulness is fairly limited at this time.

-JasonS

new sandcastle is out

Wed, 07 Jul 2010 08:50:43 +0700

At Novaleaf, we use Sandcastle to generate code documentation.

Not only code documentation, but as part of our “Novaleaf Simplified Process”, a major concept is “Close To Code”, meaning if possible, all documentation should be done in the code files.

So, code documentation tools are very important to our development methodology.

We are about 2 weeks away from moving to Xna4, which requires VS2010, and would let us support use of .Net 4.0, so i was happy to find out today that a new .NET 4.0 version of sandcastle is released.

- JasonS

agile planning poker

Tue, 06 Jul 2010 08:48:45 +0700

if you are a part of an agile team and participate in “planning poker” you might find this site interesting.

if not, move along. there’s nothing to see here.

-JasonS

free c# design pattern ebook: if you don’t own one, this...

Mon, 05 Jul 2010 08:48:43 +0700

free c# design pattern ebook: if you don’t own one, this may be your ticket….

Gamefest 2010 presentations

Sun, 04 Jul 2010 08:47:43 +0700

A msdn blog noted that the gamefest 2010 content is up and available to download

get the US or UK content

enjoy!

-JasonS

Windows file copy sucks

Sat, 03 Jul 2010 08:47:44 +0700

trying to move a few thousand files in Win2k8 server:

wait an hour for windows to “calculate” how long the file copy would take (of course, all that calculation time without actually doing a, you know… COPY)
click “cancel” and then wait 30 minutes in disgust as windows trys to figure out how to cancel a “calculating”.
open task manager and hard-kill explorer.

Then I remembered Robocopy from my old msft days. what do you know, it’s built into windows now.

What about a gui version?

Thankfully, a short google search later brought me to RichCopy, the successor to robocopy:

http://technet.microsoft.com/en-us/magazine/2009.04.utilityspotlight.aspx

so if you ever copy tons of files (who doesnt?) use this instead of the broken, tragic file copy found in windows.

-JasonS

Direct Compute Lecture Series

Fri, 02 Jul 2010 08:46:42 +0700

If you are interested in taking advantage of GPGPU development using DirectX’s DirectCompute, here’s the best chance you have to leap into it:

http://blogs.msdn.com/b/directx/archive/2010/06/15/introducing-the-directcompute-lecture-series.aspx

This lecture series offers a full noob-to-expert curriculum towards GPGPU mastery.

-JasonS

Development Methodology Documentation

Thu, 01 Jul 2010 08:46:42 +0700

part of an email i sent related to some “workflow” work i’m doing on my “spare time” this week….

I think the ISO process that Ann is spearheading is a great way for us to improve our internal workflow, and that gives us a chance to discover a better, sustainable development methodology.
previously we have used “waterfall” and “scrum” but they haven’t worked too well. here’s my summary of why:
- waterfall requires too much documentation and top down management (by me. since i’m our best dev, I should probably be doing architecture and development instead of writing docs!)
- scrum requires too much individual self-management. most people are motivated to self manage, but if they don’t have the practical skills/experience to do so, it’s too easy to get off track (or dont even know where to start!)
I discovered an interesting middle-ground, called the Agile Unified Process. So using this as the “template”, I will be creating an adaption for Novaleaf, as “simple as possible” workflow for our individual-contributors (IC’s)
- of course, that takes time, and while important in the long term, I will put this as second priority to the needed Engine Redesign.

cool .net 4 feature: Unity

Wed, 30 Jun 2010 08:45:43 +0700

http://unity.codeplex.com/

Unity is a dependency injection framework.

not a mono based game engine ;)

-JasonS