Virtual graphics like virtual RAM ???

When I plot lines or print text on screen, if the size is too big it will wrap around somewhere off-screen, and blaze a trail across my screen again, and again, and again.

How much bigger is the virtual screen compared to the 800x600 screen that I can see?

 

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Huh? What do you mean it blazes a trail across your screen again and again?

 

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It literally wraps around and comes back again.

If I print the word "hello" a million times it will scroll off the bottom of the form. Then a few seconds later it will appear at the top again, and print another column over top of the old one, and again scroll off the bottom. Then a few seconds later it will appear at the top again, and print another column over top of the two previous ones, and again scroll off the bottom....

I know how big the screen is, but how far off screen does it go before it does the wrap-around?

 

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Oh, you mean when you're programming...I thought you meant a normal application wrapped around.

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I don't know for certain, but it certainly depends on the OS. It may very well be an undefined behavior for your API or drawing device. What language, OS, and API are you using?

 

Visual Basic 6.0.

 

Your getting the wrap around because of how the frame buffer is arranged. For example, if your framebuffer looks like UCHAR frameBuf[NUM_ROW * NUM_COL] and then you write frameBuf[NUM_COL - 1] = 1 you've written to row 0, col NUM_COL-1 but when your write frameBuf[NUM_COL] = 1 you've written to row 1, col 0. This may occur in some vga modes such as 13h if your using directx with visual basic.