This is the weirdest thing, I was working away in Visual Studio 2008 when I attempted a global search and it failed indicating that ‘No files were found to look in. Find was stopped in progress.’. The weird thing is that I had selected Entire Solution and it should have worked. After some quick googling I found out that other people have had the same problem. Although the reason for it happening hasn’t been entirely explained (nor do I really care) the solution is as follows:

In VS2008 press Alt + Break to make find work again
In VS2005 press Ctrl + Scroll Lock (I haven’t tried this one)

Find works again, hurray!

Today I ran into the problem whereby printf was putting junk into a string even though it was using %s. A little perplexed about it I had a look around and saw that there is a separate format specifier that expects a wide string. My application is not compiled in Unicode but I require a wide string at this point.

So

wsprintf(buffer, L"Name %s", myWideCharString)

The above code wouldn’t work. However if I use the code below it would

wsprintf(buffer, L"Name %lS", myWideCharString)

The reason being that printf does some behind the scenes conversion and %s or %S will convert to a char*. %lS tells it that what is coming in is a wide string and to handle it as such.

I also found out that %f doesn’t work with wsprintfW, wierd and quite silly really.

Generally when you want something to flash on and off in a smooth fashion you have a duration that you want an icon to fade in and out at. You then tend to have a timer that increments up to the fade value and when it hits the fade value begins to decrement again down to zero. See the code below for an example of this in action

static const f32 totalFadeTime = 4.0

if (m_fadeUp)
{
	timer += delta;
	if (m_timer > m_revealTime)
	{
		timer = m_revealTime;
		m_fadeUp = false;
	}
}
else
{
	timer -= delta;
	if (timer < 0.0f)
	{
		timer = 0.0f;
		m_fadeUp = true;
	}
}

const f32 alpha = timer / totalFadeTime;

icon->SetAlpha(alpha);

The approach above uses linear interpolation so the fade looks quite even and bland. To get a nicer smooth fade you can use sin or cos alongside the linear value to give you a smoother looking effect. This is because of the curve of cos is not linear cos curve. Add the following lines to achieve this effect:

const f32 alpha = timer / totalFadeTime;
const f32 newAlpha = (cosf(TwoPi * alpha) - 1.0f) * -0.5f;
icon->SetAlpha(alpha);

Unfortunately I don’t have an example of this on hand to show but I does the trick nicely.

It’s been quiet around here lately. I’m going to try to make an effort to blog here a bit more, it will mostly be about my SingStar coding experiences!