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Change bold code snippets to inline code blocks

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James Gregory 2013-12-31 17:12:29 +11:00
commit 3c76d884ef
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12
47-04.md
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@ -118,16 +118,16 @@ _FillRectangleX endp
```
The two major weaknesses of Listing 47.4 both result from selecting the
plane on a pixel by pixel basis. First, endless **OUT**s (which are
plane on a pixel by pixel basis. First, endless `OUT`s (which are
particularly slow on 386s, 486s, and Pentiums, much slower than accesses
to display memory) must be performed, and, second, **REP STOS** can't be
to display memory) must be performed, and, second, `REP STOS` can't be
used. Listing 47.5 overcomes both these problems by tailoring the fill
technique to the organization of display memory. Each plane is filled in
its entirety in one burst before the next plane is processed, so only
five **OUT**s are required in all, and **REP STOS** can indeed be used;
I've used **REP STOSB** in Listings 47.5 and 47.6. **REP STOSW** could
be used and would improve performance on most VGAs; however, **REP
STOSW** requires extra overhead to set up, so it can be slower for small
five `OUT`s are required in all, and `REP STOS` can indeed be used;
I've used `REP STOSB` in Listings 47.5 and 47.6. `REP STOSW` could
be used and would improve performance on most VGAs; however, `REP
STOSW` requires extra overhead to set up, so it can be slower for small
rectangles, especially on 8-bit VGAs. Note that doing an entire plane at
a time can produce a "fading-in" effect for large images, because all
columns for one plane are drawn before any columns for the next. If this