Speed freaks...

I've been working for a client who had a Win32 based application that did some graphics creation tasks for a consumer product. They wanted to update the look and feel of the program and hired someone to create a new application for them. This engineer did a pretty good job but, through lack of personal funds and the availability of a freebie, wrote the application using the C# express beta for C#2.0.

The customer took delivery of the partial code and then discovered that to release it to their customers they'd have to back-port it to .NET version 1.1 and finish up the program. Because of the highly graphical nature of the application and because the original implementation was rather slow they asked me to pep it up a bit.

After solving many of the drawing issues and getting the application up and running we got to the stage where people were installing it to test and everyone who saw it was horrified at the startup time. Some machines saw a 35 second wait between the initial first click and the appearance of the application window. They had never seen a fat .NET app before.

There were two problems with the whole scenario. First, the cycle was to install a new copy of the app, to click the application icon and sit there with a stopwatch waiting for something to appear. This meant that every time they saw it it was going through the process of creating the native image copy for the application cache. Secondly, even though the application had a splash screen this was a part of the application that needed JIT compiling too so often it didn't appear for some time. This encouraged the user to click a second time.

To solve these problems I've tried two things. To make the splash screen appear instantly I wrote a small program launcher that just displayed the desired image and then used Process.Start to launch the real program. This gives the user the feeling that something is happening and discourages them from clicking the icon again and again. Secondly I wrote a custom installer clas that used ngen, the .NET framework native image generator, to create the native-code compiled version of the program at install time. This meant that the first run of the code already had the native image in the cache and reduced load times to the barest minimum. On a test machine I got the load time from 30 seconds down to 6 seconds total using this method.

Duality of purpose.

I find myself embarrased at times when answering questions in the various forums I hang out in. On occasion, I find myself with no other answer than "Buy the tool I created to do that".

This sometimes seems to be mercenary and is not well recieved by the users of the forum. Last year I practically gave up offering advice in a VB forum because the people who frequented it thought that the only reason I was there was to tout my wares.

To be honest, I always hesitate to answer "if you're interested in a commercial solution..." and think more than twice about posting a link to my business site but recently I've begun to wonder why people are so anti a good solution.

Looking at the situation logically, the kinds of questions I answer with a commercial offering are the ones that would start out with "Well, you need to build yourself a small nuclear power station. First mine some uranium and then..." followed by a couple of pages of complex overview. These are not trivial questions then and hence have no trivial answer.

What I really don't understand is when someone pops up on line and demands a FREE-SOURCE-CODE-INCLUDED tool that does just exactly what they want and moans like the clappers if someone suggests they should pay a few bucks registration fee or even buy a developer license

Work is money and money is work. If someone is faced with a weeks work figuring out how to do a specific task and can get the answer for a thirty buck registration fee then how can they be so indignant when someone says "Ok, I'll save you a weeks worth of finding out how to do this yourself in exchange for the cost of one hour of your precious time.

If it were me, and it frequently has been, I'd jump at the chance and register there and then. Then again, like my dad says "Theres nought so strange as folk"

GPS Software

I recently purchased a GPS system for my car. The hardware is a Windows CE device running dedicated software from the German Navigon company. This little box of tricks will plan routes for you and speaks instructions such as "At the next junction, turn right" or "Leave the roundabout at the third exit".

In itself, the machine is an excellent companion to anyone who needs door-to-door driving instructions with intelligent route planning and re-planning if you, despite all the instructions, take a wrong turn or end up on a detour that closes the roads the machine thinks you should be taking.

What makes this, in my opinion, the greatest thing since sliced bread is Navigon's customer support service. I had a problem with my machine that was my own fault and contacted Navigon to see if I could fix the problem. I fully expected to have to pay for the fix but Navigon exchanged a few e-mails and have fixed me up like new.

So many companies these days make you jump through hoops and do as much as possible to place the blame for the fault on the purchaser to save money on support. Navigon's excellent customer support policies were a real breath of fresh-air.

More printer ink thoughts

After printing a 1000 page PDF file I decided that the printer ink situation should be resolved once and for all.

I wrote this article to show how to refil Epson TO452, TO453, TO454 and TO441 cartridges.

Serif fonts.

I have developed an aversion to serif fonts such as Times New Roman. For preference I use Verdana which has subtle differences from Arial or MS Sans-Serif and which I think is a far more readable typeface.

Arial is a slightly cramped typeface that has connotations of a serif font particularly because of the lower case "a" which I find to stand out almost as though it was purposefully created in a different style from the rest of the font.

Verdana has an open style which is far better proportioned and the "a" fits right in with the rest of the font as if it belongs.

Times is a very cramped typeface, this paragraph is the same point size as the Verdana above but you must agree is not nearly as easy on the eye. It reminds me of cheap paperback books and seems to lower the quality of the text. I know it's almost a 'traditional' font but I do wish that it wasn't the default for everything.

Georgia is Verdana's serif cousin and is more open and readable so as a compromise I tend to use it when serif fonts are required.

For me, Verdana is the queen of fonts.

Unsafe isn't

I've noticed that many programmers seem to have an irrational fear of the "unsafe" keyword in C#. It's almost as though they are afraid that if they use it in their code then program will turn into a Frankenstiens Monster and leap opon them in their sleep.

Unsafe refers only to the fact that the code might reference unmanaged and hence non type-safe code. Not that one is taking a calculated risk by using it.

Personally, I only use unsafe where the highest performance is required and I don't want anything to intervene between my code and the bytes it's working on. In most of my puplicly available examples these days I use the Marshal class because it enables me to create code in C# which is readily translated to VB. This is of course just my lazy nature and not a fear of the evil that may befall me if I use that dreaded keyword.

Turn the world on it's head!

Today I have had a bit of a shock. In response to a newsgroup posting I decided to update my article on generating 1 bit per pixel images from 24bpp colour. The original article used a mixture of Bitmap.GetPixel and LockBits to determine the pixel brightness and write the single bit pixel to the image array and I had decided to convert this to a LockBits solution on both sides of the equation for the sake of completeness.

I re-wrote the C# code so that instead of using unsafe pointers it used the Marshal class to read and write the bytes. This made the code identical in function to the VB conversion. After testing the C# code I did a quick conversion to VB and wran the two applications on the same image.

I noticed that the VB application seemed to be faster so I added a diagnostic routing to time how long the central part of the loop, the one that actually does the conversion, took. To make sure the code had a good chunk of data to work with I used an image that was 4000*3200 pixels.

To my great surprise the VB code is consistently faster by over three seconds with the C# doing the loop in around eight seconds and the VB running the functionally identical code in only five.

I have seen instances before where the VB compiler was demonstrably better at generating code than the C# one but have never seen it so clearly shown to be superior at simple tasks than the C# compiler.

The timed code is shown in both C# and VB here:

C#

DateTime dt=DateTime.Now;

//scan through the pixels Y by X
int x,y;
for(y=0;y {
for(x=0;x {
//generate the address of the colour pixel
int index=y*bmdo.Stride+(x*4);
//check its brightness
if(Color.FromArgb(Marshal.ReadByte(bmdo.Scan0,index+2),
Marshal.ReadByte(bmdo.Scan0,index+1),
Marshal.ReadByte(bmdo.Scan0,index)).GetBrightness()>0.5f)
this.SetIndexedPixel(x,y,bmdn,true); //set it if its bright.
}
}

//tidy up
bm.UnlockBits(bmdn);
img.UnlockBits(bmdo);

//show the time taken to do the conversion
TimeSpan ts=dt-DateTime.Now;

VB

'for diagnostics
Dim dt As DateTime = DateTime.Now

'scan through the pixels Y by X
Dim y As Integer
For y = 0 To img.Height - 1
Dim x As Integer
For x = 0 To img.Width - 1
'generate the address of the colour pixel
Dim index As Integer = y * bmdo.Stride + x * 4
'check its brightness
If Color.FromArgb(Marshal.ReadByte(bmdo.Scan0, index + 2), Marshal.ReadByte(bmdo.Scan0, index + 1), Marshal.ReadByte(bmdo.Scan0, index)).GetBrightness() > 0.5F Then
Me.SetIndexedPixel(x, y, bmdn, True) 'set it if its bright.
End If
Next x
Next y
'tidy up
bm.UnlockBits(bmdn)
img.UnlockBits(bmdo)

'show the time taken to do the conversion
Dim ts As TimeSpan = dt.Subtract(DateTime.Now)

I'll have to compare the IL for the two compiled sections to see where the C# compiler fails to get that extra few ergs.

Does there have to be a reason?

I am a proponent of wordy explanations but there are some times when a simple and definitive answer should be taken at face value and not questioned.

Children often ask "Daddy, what would happen if I were to poke my tongue in the electrical outlet?" wherupon daddy will reply "You'll die a horrible and painful death son". This should be enough of an answer and should be heeded by all small boys.

When a programmer asks "Can I store the Graphics object?" the answer is "No!". This is one of those definitive answers that is usually questioned but which always ends up being "No!" however many times or in however many different ways it's asked.

Just to recap....

Do not store the Graphics object. Do not store it in a local variable, a static variable, a shared variable, an object, a structure or a database. Do not put it in an envelope and post it to your aunt, do not draw a picture of it, do not photocopy it, do not have Monet make a painting of it.
Do not put it in your pocket for later, do not hash encode it and e-mail it to the CIA, do not put it on a Post-it note and stick it to your screen, do not grind it into powder and sniff it up your nose with the other stuff you just had. In short....

DO NOT STORE THE GRAPHICS OBJECT!

Falling in love again.

I have always been a "client side" kinda guy. Most of the work I do is fairly heavy graphics code and I'm reasonably good at problem solving when I can sit down in front of a good algorithm and bash out some code.

I am forced through circumstance to do work in HTML and I generally use FrontPage for my web site work but I can honestly say that HTML and presentation stuff of that nature is BORING BORING BORING so I tend not to put as much effort into it as I normally do my other work. I find that this reluctance is also affected by the fact that it's so dammned complicated to get a web site to do anything at-all interesting and the mix of script and the hokey way it fits into HTML coupled with the truly abysmal debugging options one has for working with it means that I do the minimum possible to make my sites work.

Up until recently, I had hosted my sites on cheap servers that didn't offer ASP.NET services so I was stuck with whatever active stuff I could be bothered to learn in the JavaScript fashion. About a year ago however I moved BobPowell.NET to a server at Brinkster because they had much more bandwidth than the godaddy servers I had been on before.

Now, I'm a great believer in "If it ain't broke, don't fix it!" so I have used the brinkster service as a high bandwidth home for my old site and not made that many changes to it. Within the last few weeks however I have got back into using ASP.NET beause I'm writing a complete licensing, support and customer management package for XRay tools. Of course, I knew how this all worked from a theoreical standpoint and had done lots of sample stuff on ASP.NET but never sat down to write an end-to-end application in it.

Well folks, I'm in love. What an excellent way to create an application. It has all the visual afdvantages of HTML with all the algorithmic advantages of client-side work. I can write my web-site in the same way that I'd write a Windows Forms application and it works so well!

I'll definitely be putting LOTS more active stuff on my sites from now on. GO ASP+!!!

Bitmap manipulations.

I keep having online conversations with people who bemoan the fact that their computers have a spot of bother dealing with images with pixel counts of 10,000 * 8,000 or 13,000 * 18,000. They complain that the image scrolls slowly and they can't drag an image about but they obviously haven't the faintest idea of the implications of such an image.

One bright spark complained of the poor performance of an image having 13000 by 18000 pixels so I sat and did a little calculation which, I think, brings home just how much information is stored in such an image.

13000 * 18000 is 234000000. Multiply this by 4 for the bit depth of images stored in memory on the computer and you get 936000000 (936 million). Ok, A page of type in a programmere reference book runs out at about 88 characters by 36 lines. Thats 3168 characters per side and 6336 for a single sheet of paper.

On my bookshelves I have several books over 1000 pages in length and a thousand page book works out to be somewhere in the region of two inches thick. Our 6336 characters goes into 936000000 about 147727 times. This means a book with 148 thousand pages, 2 inches per thousand remember, is 24.6 feet thick.

Now I don't have many bookshelves in my house that are 25 feet long but if I had one I'd know that that was one fat book!

Even given the power of todays computers that's one huge chunk of info to mess around with. Why don't people understand that before they start whining about the scrolling performance of their image viewer application?

Still alive and kickin'

You may ask yourself "What the heck is that Bob Powell up to these days?" It's true that I've not paid attention to the Blog much because my work has just gone crazy and I've had months of pretty intense stuff going on and no time to report on other things.

I'm writing a book. This is not too surprising I suppose but what will really blow your socks off is that it's a book for Visual Basic programmers.

As a self-promoting guru I get vast amounts of mail from people who ask for help on every subject, not just Graphics, and I have seen a dire need for a book that explains how to create a correctly object-oriented architecture for VB users. So many people come from the VB6 world and discover that although VB.NET is syntactically similar the principles of software architecture in an object-oriented system such as .NET is a mystery. Consequently they make the most fundamental mistakes and create truly horrible applications that are beset with faults.

The book is entitled "Object Oriented Programming for .NET" and is presented in both VB and C# but with the emphasis on the VB angle.

The "day job" is keeping me well employed doing exiting things with public-address advertizing systems. I must say that there is rarely a boring day.

Keeping an amount of churn in the GDI+ FAQ and Windows Forms Tips and Tricks also puts a load on.

Finally WellFormed is on my list of important items and I'm working on a new system that will deliver content to subscribers via the web. I originally hosted the service with a provider who shall remain nameless but which SUCKED! and cost me too much money and time. Now WellFormed.NET is on Brinkster but the application that serves the content is even more work for my thinly spread working day. I have a prelim version working but it has bugs that I just don't have time to chase at this second.

I suppose being over-employed is better than being under-employed :-)

I've been thinking of a plan

I recently started a beginners guide to GDI+ which seems to have put my site hits up by about 10%.

Are simple guides more popular?

Just thinking out loud here, which is what a blog is I suppose.

VAT collection by non EU sites

A question that has nagged at my brain in the last few months is "How do non EU companies collect VAT"
You see, VAT or Value Added Tax is europes form of sales tax. It is levied at a swingeing rate of up to 20% on some items so it can be a significant portion of the cost.

European union companies that collect VAT are obliged by law to put their VAT registration numbers on all invoices that charge VAT. Recently however I've noticed that many on-line shopping systems charge VAT to EU customers but don't put their VAT numbers onto the sites or on the invoices making me wonder if this is just a handy way for a US company to extort 20% of sales from europeans.

I have been charged VAT by Symantec and I don't know their VAT number for my company accounts.

Moreover, the rate of VAT isn't in line with the VAT rates in the countries to which they sell. This leads me to believe its bogus too because if there's one thing a tax man is keen on it's getting the percentages right. You see, the VAT rate for Symantec products is 20% no matter what EU country the purchase is made in. Does this VAT collected go into the general pool of VAT for Europe. I suspect not.

If I pay VAT I want to know it's going to the place it's supposed to go or I want a refund if the application of sales tax is just there to enrich the company because they think no-one has noticed.

Programming styles I use and why....

When the code you write is for the benefit of others, a clear and readable coding style is as important as a good prose style. This is my personal style guide which I use in all my programming.

#1 Naming conventions.

Concise naming is important if code is consumed by someone else. Cryptic names for variables, methods and properties are for obfuscators, not programmers.

Private Fields begin with an underbar and a lower case letter such as _data. Long names are CamelCased such as _myLongData.

Accessor properties remove the underbar and capitalize the first letter such as Data or MyLongData.

Variables in a method begin with a lower-case letter and are camel-cased if long such as "variable" or "myLongVariable". Parameters passed to a method follow similar convention.

Class names begin with capital letters and are camel-cased where necessary.

Class, method, property and field names are indicative of function wherever possible.

#2 Code layout

Code should be well laid out and as concise as possible.

Whitespace doesn't impact code size but can make a lot of difference to readability. Blank lines can be as informative as lines full of code.

Namespace items, classes, methods, properties and field groups are separated by white space to give separation between elements so that the eye automatically distinguishes between one section and another.

Braces are on their own lines and indentation is used to indicate nesting or scope. The exception to this rule is in the case of simple accessor properties where the get and set accessors may be defined on a single line. Acessors that are more complex than assigning the value to the associated private field follow the method brace and indentation rules.

#3 Comments

Be liberal and verbose with comments and documentation. Basic Inline XML documentation is a great help when studying a class library but little or no use when trying to get into the head of the programmer, even if that programmer may have been you two years ago. Remember the remarks and examples as well as internal comments

See the code example here.

Fun with DHTML

I just published a new article on the Tips and Tricks page but this one has a difference. You may have noticed a few of my pages have optional C# and VB code sections that can be chosen on-the-fly as you read. These are simple DHTML scripts that turn different sections of the page on or off according to choice. The problem was with the method, which I got from another web-site I hasten to add, was that if more than one section of code needs swapping out then the javascript becomes ever more complex with each new bit. What I needed was a way of turning on all the C# or all the VB in one go.

This is the first time I've messed about with DHTML in any serious way and so I'm rather pleased with the end result. What I did was give all the C# or VB statements a unique ID based on the pattern "CSA" "CSB" or "VBA" "VBB" and so-on. Then I created code that went through all the specially named elements one by one turning them on or off as needed. Finally I put a couple of sexy mouseover buttons on the page to finish the thing up and voila...

If you'd like to see the code in it's production form go read the article. If you'd like to see the bare-bones dynamic page you can see it here.

I'm sure I'll get a bunch of responses from clever DHTML jockeys telling me it's all wrong but I'm as pleased as a dog with two tails...

Well Formed

I have temporarily suspended all Well Formed subscriptions while work goes ahead on the new site. I am currently fielding tens of requests per day that go something like this.

Subscriber: "Bob, I haven't seen the latest issue of Well Formed. Whats up??"

Bob: "Hi, your e-mail system bounced the subscription, heres a duplicate"

Subscriber: "Bob, are you there??"

Bob: "Hi, yes, your e-mail bounced that one too because it had an attachment, why not try using yahoo mail or something"

Subscriber: "Bob, I have written to you twice with no reply. Why are you ignoring me??"

Bob: "Dude, I'm not ignoring you, your SPAM filter has decided I am bad news and you can't see my replies"

Subscriber: "Bob, you are an ignorant useless git and I'm cancelling my subscription forthwith. I've never seen such unprofessional crap in all my years as a blah blah blah"

You can see that when this happens about 10 times a day it make me happy, contented and glad to be of service _NOT_.

Big changes going on.

If you've visited my site recently you'll have noticed some major changes going on. BobPowell.net is going back to its roots inasmuch as it will no longer provide consulting or tools offerings but will be a place for publishing information such a the FAQ and Tips and Tricks. It's becoming increasingly difficult to separate my need to educate from my need for an income and I don't want my personal site to degenerate into a mish-mash of confusing stuff that people go to for help but that screams "money-money-money!!!" at every turn.

For the commercial side I have a couple of projects in work. WellFormed.net is a site that will shortly be running the Well Formed Magazine and XRayTools.net will be providing tools to developers in a clear-cut and commercial manner. Both of these sites will sponsor BobPowell.net. This will allow me to get on with the business of creating articles and code of the higest quality possible for the FAQ and Tips and Tricks along with whatever else comes along.

Google Adsense is my only concession to online commercialism on that site and I came to a bit of a revalation the other day when I was explaining to my son Robyn, who wants to be a webmaster bye-the-way, that effectively, AdSense makes the hosting cost of the site free! This means that a site such as bobpowell.net can be self sustaining and self justifying without even worrying about the commercial aspect of trying to make a hard-sell every time someone visits the site.

Things will be a little bit up-in-the-air for a while but when they settle down again I hope that the new look and feel coupled with the philosophy of free information will be well received.

The best upgrade so-far.

I recently purchased a 19in. LCD flat-screen to replace my cheap little 15in. job. The big screen is excellent for editing code because the resolution is that much higher and I was all-ready to give the smaller monitor to one of my children when I realized I had an old matrox PCI video card hanging around somewhere. I found it, plugged in and attached the 15in. LCD monitor to it.

What an incredible difference! I am convinced that the combination of both monitors is probably ten times more useful than just replacing one monitor with a larger one. Of course, having the 19in. screen is great for editing code but to be able to drag stuff from one monitor to another is a real boon. Now, when I read newsgroups and click on a link Internet explorer pops up on the second monitor and doesn't obscure the newsgroup. I can run a virtual machine in full-screen mode on the second monitor to test longhorn or whidbey. The readable area of both screens multiplies the usefulness of the display rather than simply adding to it.

Of course, the secondary display will not handle some graphics tasks because the matrox card is a bit long in the tooth but for text and simple graphics it's adequate. I cannot play a DVD movie on the secondary screen for example but I can play one on the main screen and still browse the Internet on the other.

As the title of this post suggests, this is probably the best upgrade I've ever given my computer and would highly recommend it to anyone that spends a long time switching between windows as I do.

Long time no blog...

My day job is keeping me incredibly busy. I just got Longhorn 4074 and it's SDK up and running on Virtual PC so maybe I'll report on some avalon stuff later.

Anyway, I'm not dead...

New GDI+ article

If you're not already subscribed to the GDI+ FAQ RSS feed, now would be a good time to do so.

A new article on creating text-halo effects has just been published.