Fossil SCM

Modernized table-based formatting in delta_encoder_algorithm doc.

wyoung 2024-02-18 13:19 trunk
Commit 65853cc1e4673726fa06a148ec6afa0685acc23eb1b2045c279e235fea7eb572
--- www/delta_encoder_algorithm.wiki
+++ www/delta_encoder_algorithm.wiki
@@ -1,7 +1,7 @@
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<title>Fossil Delta Encoding Algorithm</title>
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-<nowiki>
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+
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<h2>Abstract</h2>
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<p>A key component for the efficient storage of multiple revisions of
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a file in fossil repositories is the use of delta-compression, i.e. to
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store only the changes between revisions instead of the whole
@@ -217,15 +217,13 @@
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<h3 id="rhdef">4.1 Definition</h3>
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<p>Assuming an array Z of NHASH bytes (indexing starting at 0) the
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hash V is computed via</p>
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-<p align=center><table><tr><td>
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-<p><img src="encode1.gif" align="center"></p>
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-<p><img src="encode2.gif" align="center"></p>
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-<p><img src="encode3.gif" align="center"></p>
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-</td></tr></table></p>
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+<div align="center"><img src="encode1.gif"></div>
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+<div align="center"><img src="encode2.gif"></div>
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+<div align="center"><img src="encode3.gif"></div>
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where A and B are unsigned 16-bit integers (hence the <u>mod</u>), and
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V is a 32-bit unsigned integer with B as MSB, A as LSB.
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<h3 id="rhincr">4.2 Incremental recalculation</h3>
@@ -234,15 +232,13 @@
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hash V (and components A and B), the dropped
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byte <img src="encode4.gif" align="center">, and the new byte
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<img src="encode5.gif" align="center"> , the new hash can
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be computed incrementally via: </p>
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-<p align=center><table><tr><td>
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-<p><img src="encode6.gif" align="center"></p>
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-<p><img src="encode7.gif" align="center"></p>
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-<p><img src="encode8.gif" align="center"></p>
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-</td></tr></table></p>
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+<div align="center"><img src="encode6.gif"></div>
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+<div align="center"><img src="encode7.gif"></div>
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+<div align="center"><img src="encode8.gif"></div>
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<p>For A, the regular sum, it can be seen easily that this the correct
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way recomputing that component.</p>
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<p>For B, the weighted sum, note first that <img src="encode4.gif"
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--- www/delta_encoder_algorithm.wiki
+++ www/delta_encoder_algorithm.wiki
@@ -1,7 +1,7 @@
1 <title>Fossil Delta Encoding Algorithm</title>
2 <nowiki>
3 <h2>Abstract</h2>
4
5 <p>A key component for the efficient storage of multiple revisions of
6 a file in fossil repositories is the use of delta-compression, i.e. to
7 store only the changes between revisions instead of the whole
@@ -217,15 +217,13 @@
217 <h3 id="rhdef">4.1 Definition</h3>
218
219 <p>Assuming an array Z of NHASH bytes (indexing starting at 0) the
220 hash V is computed via</p>
221
222 <p align=center><table><tr><td>
223 <p><img src="encode1.gif" align="center"></p>
224 <p><img src="encode2.gif" align="center"></p>
225 <p><img src="encode3.gif" align="center"></p>
226 </td></tr></table></p>
227
228 where A and B are unsigned 16-bit integers (hence the <u>mod</u>), and
229 V is a 32-bit unsigned integer with B as MSB, A as LSB.
230
231 <h3 id="rhincr">4.2 Incremental recalculation</h3>
@@ -234,15 +232,13 @@
234 hash V (and components A and B), the dropped
235 byte <img src="encode4.gif" align="center">, and the new byte
236 <img src="encode5.gif" align="center"> , the new hash can
237 be computed incrementally via: </p>
238
239 <p align=center><table><tr><td>
240 <p><img src="encode6.gif" align="center"></p>
241 <p><img src="encode7.gif" align="center"></p>
242 <p><img src="encode8.gif" align="center"></p>
243 </td></tr></table></p>
244
245 <p>For A, the regular sum, it can be seen easily that this the correct
246 way recomputing that component.</p>
247
248 <p>For B, the weighted sum, note first that <img src="encode4.gif"
249
--- www/delta_encoder_algorithm.wiki
+++ www/delta_encoder_algorithm.wiki
@@ -1,7 +1,7 @@
1 <title>Fossil Delta Encoding Algorithm</title>
2
3 <h2>Abstract</h2>
4
5 <p>A key component for the efficient storage of multiple revisions of
6 a file in fossil repositories is the use of delta-compression, i.e. to
7 store only the changes between revisions instead of the whole
@@ -217,15 +217,13 @@
217 <h3 id="rhdef">4.1 Definition</h3>
218
219 <p>Assuming an array Z of NHASH bytes (indexing starting at 0) the
220 hash V is computed via</p>
221
222 <div align="center"><img src="encode1.gif"></div>
223 <div align="center"><img src="encode2.gif"></div>
224 <div align="center"><img src="encode3.gif"></div>
 
 
225
226 where A and B are unsigned 16-bit integers (hence the <u>mod</u>), and
227 V is a 32-bit unsigned integer with B as MSB, A as LSB.
228
229 <h3 id="rhincr">4.2 Incremental recalculation</h3>
@@ -234,15 +232,13 @@
232 hash V (and components A and B), the dropped
233 byte <img src="encode4.gif" align="center">, and the new byte
234 <img src="encode5.gif" align="center"> , the new hash can
235 be computed incrementally via: </p>
236
237 <div align="center"><img src="encode6.gif"></div>
238 <div align="center"><img src="encode7.gif"></div>
239 <div align="center"><img src="encode8.gif"></div>
 
 
240
241 <p>For A, the regular sum, it can be seen easily that this the correct
242 way recomputing that component.</p>
243
244 <p>For B, the weighted sum, note first that <img src="encode4.gif"
245

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