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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
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56-02.md
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@ -12,13 +12,13 @@ pages: 1050-1053
Ah, but what is an "equivalent amount"? Think of it this way. If a
destination edge is 100 scan lines high, it will be stepped 100 times.
Then, we'll divide the **SourceXWidth** and **SourceYHeight** lengths of
Then, we'll divide the `SourceXWidth` and `SourceYHeight` lengths of
the source edge by 100, and add those amounts to the source edge's
coordinates each time the destination is stepped one scan line. Put
another way, we have, as usual, arranged things so that in the
destination polygon we step **DestYHeight** times, where **DestYHeight**
destination polygon we step `DestYHeight` times, where `DestYHeight`
is the height of the destination edge. The this approach arranges to
step the source image edge **DestYHeight** times also, to match what the
step the source image edge `DestYHeight` times also, to match what the
destination is doing.
![**Figure 56.3**  *Mapping a texture onto a 2-D rotated polygon.*](images/56-03.jpg)
@ -26,18 +26,18 @@ destination is doing.
Now we're able to track the coordinates of the polygon edges through the
source image in tandem with the destination edges. Stepping across each
destination scan line uses precisely the same technique, as shown in
Figure 56.4. In the destination, we step **DestXWidth** times across
Figure 56.4. In the destination, we step `DestXWidth` times across
each scan line of the polygon, once for each pixel on the scan line.
(**DestXWidth** is the horizontal distance between the two edges being
(`DestXWidth` is the horizontal distance between the two edges being
scanned on any given scan line.) To match this, we divide
**SourceXWidth** and **SourceYHeight** (the lengths of the scan line in
`SourceXWidth` and `SourceYHeight` (the lengths of the scan line in
the source image, as determined by the source edge points we've been
tracking, as just described) by the width of the destination scan line,
**DestXWidth**, to produce **SourceXStep** and **SourceYStep**. Then, we
just step **DestXWidth** times, adding **SourceXStep** and
**SourceYStep** to **SourceX** and **SourceY** each time, and choose the
nearest image pixel to (**SourceX**,**SourceY**) to copy to (**DestX**,
**DestY**). (Note that the names used above, such as **SourceXWidth**,
`DestXWidth`, to produce `SourceXStep` and `SourceYStep`. Then, we
just step `DestXWidth` times, adding `SourceXStep` and
`SourceYStep` to `SourceX` and `SourceY` each time, and choose the
nearest image pixel to (`SourceX`,`SourceY`) to copy to (`DestX`,
`DestY`). (Note that the names used above, such as `SourceXWidth`,
are used for descriptive purposes, and don't necessarily correspond to
the actual variable names used in Listing 56.2.)