| extract.h |
This chunk specifies how to split an image into segments for
scaling.
There are J horizontal and K vertical segments. These segments divide
the image into J*K regions as follows (where J=4 and K=3):
F0 S0 F1 S1
+-----+----+------+-------+
S2| 0 | 1 | 2 | 3 |
+-----+----+------+-------+
| | | | |
| | | | |
F2| 4 | 5 | 6 | 7 |
| | | | |
| | | | |
+-----+----+------+-------+
S3| 8 | 9 | 10 | 11 |
+-----+----+------+-------+
Each horizontal and vertical segment is considered to by either
stretchable (marked by the Sx labels) or fixed (marked by the Fy
labels), in the horizontal or vertical axis, respectively. In the
above example, the first is horizontal segment (F0) is fixed, the
next is stretchable and then they continue to alternate. Note that
the segment list for each axis can begin or end with a stretchable
or fixed segment.
The relative sizes of the stretchy segments indicates the relative
amount of stretchiness of the regions bordered by the segments. For
example, regions 3, 7 and 11 above will take up more horizontal space
than regions 1, 5 and 9 since the horizontal segment associated with
the first set of regions is larger than the other set of regions. The
ratios of the amount of horizontal (or vertical) space taken by any
two stretchable slices is exactly the ratio of their corresponding
segment lengths.
xDivs and yDivs point to arrays of horizontal and vertical pixel
indices. The first pair of Divs (in either array) indicate the
starting and ending points of the first stretchable segment in that
axis. The next pair specifies the next stretchable segment, etc. So
in the above example xDiv[0] and xDiv[1] specify the horizontal
coordinates for the regions labeled 1, 5 and 9. xDiv[2] and
xDiv[3] specify the coordinates for regions 3, 7 and 11. Note that
the leftmost slices always start at x=0 and the rightmost slices
always end at the end of the image. So, for example, the regions 0,
4 and 8 (which are fixed along the X axis) start at x value 0 and
go to xDiv[0] and slices 2, 6 and 10 start at xDiv[1] and end at
xDiv[2].
The array pointed to by the colors field lists contains hints for
each of the regions. They are ordered according left-to-right and
top-to-bottom as indicated above. For each segment that is a solid
color the array entry will contain that color value; otherwise it
will contain NO_COLOR. Segments that are completely transparent
will always have the value TRANSPARENT_COLOR.
The PNG chunk type is "npTc".
|
6512 |
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| LICENSE |
|
525 |
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| qt_attribution.json |
|
373 |
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| REUSE.toml |
|
201 |
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