Speed question

qbasicking · Jun 9, 2004

I am going to be using an offscreen screen 13 buffer (one dimension) so I am going to have to use (y * 320 + x)64000 times every frame. I am assembly illiterate, I was wondering if someone out there would help me out with a line of assembly to do that quicker than Qbasic would.

Is there a reason hexidecimal is used more often than decimal, is it faster?

CubeE101 · Jun 9, 2004

Y * 320

is the same as

(Y * 256) + (Y * 64)

or

(Y * 2^8) + (Y * 2^6)

So

Offset = Y<<8 + Y<<6 + X

Something like this:

Code:

MOV AX, (y)
MOV BX, AX
SHL AX, 8
SHL BX, 6
ADD AX, BX
MOV BX, (x)
ADD AX, BX

I's been awile since I did this so you might get someone else to help you with the details...

Have Fun, Be Young... Code BASIC
-Josh

http://cubee.topcities.com

PROGRAMMER: Red-eyed, mumbling mammal capable of conversing with inanimate objects.

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Speed question

qbasicking

Programmer

CubeE101

Programmer

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