Understood. Thanks for your help Shawn, as always.

[quote user="Shawn Hargreaves"]if your processing code reduces the size of the data in any way (even using quite expensive CPU computations for fancy compression algorithms), that is likely to be a major perf win.[/quote]This is precisely what I am thinking.  My only real concern with this is to do the compression in a way such that ...

I hadn't considered smart HD controllers with internal caches & read-ahead buffers, etc.  I want to read the data into memory as fast as the HD reveals it, and just because it reads ahead, which speeds up the next read, does this speed up the next 1,000,000 reads?  Or is it still faster to just read all 200,000,000 bytes in one ...

[quote user="fr3shme4t"]You can always read the whole file and then use a memory stream if you're really worried about I/O speed.[/quote]I am concerned with I/O speed reading 200 MB+ and the CPU speed of processing of 12,000,000 such structures.  I just want raw access, as close to the hardware (and software) as I can get, so I ...

[quote user="Shawn Hargreaves"][quote user="JasonD"]Doing multiple reads on small amounts of data is slow.  [/quote]Have you timed this, or are you guessing? My experience is that BinaryReader is usually pretty fast.[/quote]I am guessing based on past experience (i.e. DOS days) when I timed reading in files 1 byte (or ...

If the object is defined as a set of 2D lines, look up circle/line collision.  If it's in 3D, look up sphere/plane collision.  This should be a good start.  Once you know there's a collision, determining the slope shouldn't be difficult.

[quote user="venator"]Thanks can someone tell me the exact syntax please.[/quote]Type SpriteBatch.Draw() and cursor over the Draw, and press F1 or F12.  The best way to learn is to look up the details from MSDN yourself.  It's a good habit to get used to.

My recommendation is to go through the XNA 2D Tutorial.  It will take one night.  This will show you how quickly you can make a simple game in C# using XNA.  The time to make a fully polished game takes far longer though.  Check out the Arkedo Series: these 2 guys are putting out these games almost at the rate of one a ...

Gametime doesn't "fire".  Update() "fires", it is called with gametime information about how much time has passed for the last frame, which is a good approximation of how long it will take to generate the next frame.  Knowing this, you move the objects in the world how far they'd move in this amount of ...

Put a breakpoint on the text drawing code.  See if it's ever run. If it's not, why not?  See what variables are set to that cause it to be skipped. You have, basically, in a switch statement: "if (xxx) then DrawText()" So see what "xxx" equals.  Is it true?  If not, can it become true?  ...