SimpleAnimation.htm 19 KB

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  1. <html xmlns:MSHelp="http://msdn.microsoft.com/mshelp" xmlns:msxsl="urn:schemas-microsoft-com:xslt" xmlns:xanx="http://schemas.microsoft.com/developer/xanx/2005"><head><meta http-equiv="Content-Type" content="text/html; charset=utf-8" /><meta name="save" content="history" /><title>Simple Animation Sample</title>
  2. <style><!--
  3. /***********************************************************
  4. * SCRIPT-SUPPORTING STYLES
  5. ***********************************************************/
  6. /* Defines the userData cache persistence mechanism. */
  7. .userDataStyle
  8. {
  9. behavior: url(#default#userData);
  10. }
  11. /* Used to save the scroll bar position when navigating away from a page. */
  12. div.saveHistory
  13. {
  14. behavior: url(#default#saveHistory);
  15. }
  16. /* Formats the expand/collapse images for all collapsible regions. */
  17. img.toggle
  18. {
  19. border: 0;
  20. margin-right: 5;
  21. }
  22. /* Formats the Language filter drop-down image. */
  23. img#languageFilterImage
  24. {
  25. border: 0;
  26. margin-left: 0;
  27. vertical-align: middle;
  28. }
  29. /* Formats the Members Options filter drop-down image. */
  30. img#membersOptionsFilterImage
  31. {
  32. border: 0;
  33. margin-left: 0;
  34. vertical-align: middle;
  35. }
  36. /* Formats the Collapse All/Expand All images. */
  37. img#toggleAllImage
  38. {
  39. margin-left: 0;
  40. vertical-align: middle;
  41. }
  42. /* Supports XLinks */
  43. MSHelp\:link
  44. {
  45. text-decoration: underline;
  46. color: #0000ff;
  47. hoverColor: #3366ff;
  48. filterString: ;
  49. }
  50. body
  51. {
  52. background: #FFFFFF;
  53. color: #000000;
  54. font-family: Verdana;
  55. font-size: medium;
  56. font-style: normal;
  57. font-weight: normal;
  58. margin-top: 0;
  59. margin-bottom: 0;
  60. margin-left: 0;
  61. margin-right: 0;
  62. width: 100%;
  63. /*font-size: 110%;*/
  64. }
  65. div.section
  66. {
  67. margin-left: 15px;
  68. }
  69. div.hxnx5
  70. {
  71. margin-left: 1.5em;
  72. }
  73. /* Font for all headings */
  74. h1, h2, h3, h4, h5, h6
  75. {
  76. font-family: Verdana, Arial, Helvetica, sans-serif;
  77. margin-top: 18;
  78. margin-bottom: 8;
  79. font-weight: bold;
  80. }
  81. h1
  82. {
  83. font-size: 130%;
  84. color: #003399;
  85. }
  86. div#scrollyes h1 /* Changes font size for full-scrolling topic */
  87. {
  88. font-size: 150%;
  89. }
  90. h2
  91. {
  92. font-size: 122%;
  93. }
  94. h3
  95. {
  96. font-size: 115%;
  97. margin-top: 9;
  98. margin-bottom: 4;
  99. }
  100. h4
  101. {
  102. font-size: 115%;
  103. margin-top: 9;
  104. margin-bottom: 4;
  105. }
  106. h5
  107. {
  108. font-size: 100%;
  109. margin-top: 9;
  110. margin-bottom: 4;
  111. }
  112. h6
  113. {
  114. font-size: 100%;
  115. margin-top: 9;
  116. margin-bottom: 4;
  117. }
  118. ul p, ol p, dl p
  119. {
  120. margin-left: 0em;
  121. }
  122. p
  123. {
  124. margin-top: .6em;
  125. margin-bottom: .6em;
  126. }
  127. td p
  128. {
  129. margin-top: 0.0em;
  130. margin-bottom: 0.6em;
  131. }
  132. dd p
  133. {
  134. margin-top: 0.0em;
  135. margin-bottom: 0.6em;
  136. }
  137. .image
  138. {
  139. text-align: center;
  140. }
  141. dl
  142. {
  143. margin-top: 0em;
  144. margin-bottom: 1.3em;
  145. }
  146. dd
  147. {
  148. margin-bottom: 0em;
  149. margin-left: 1.5em;
  150. }
  151. dl.glossary dd
  152. {
  153. margin-bottom: 0em;
  154. margin-left: 1.5em;
  155. }
  156. dt
  157. {
  158. margin-top: .6em;
  159. margin-bottom: 1;
  160. }
  161. ul, ol
  162. {
  163. margin-top: 0.6em;
  164. margin-bottom: 0.6em;
  165. }
  166. ol
  167. {
  168. margin-left: 2.5em;
  169. }
  170. ul
  171. {
  172. list-style-type: disc;
  173. margin-left: 1.9em;
  174. }
  175. li
  176. {
  177. margin-bottom: 0.4em;
  178. }
  179. ul ol, ol ol
  180. {
  181. list-style-type: lower-alpha;
  182. }
  183. pre
  184. {
  185. margin-top: .6em;
  186. margin-bottom: .6em;
  187. font: 105% Lucida, mono;
  188. color: #000066;
  189. }
  190. code
  191. {
  192. font-family: Monospace, Courier New, Courier;
  193. font-size: 105%;
  194. color: #000066;
  195. }
  196. table.userdata td
  197. {
  198. background: #ffffff;
  199. background-color: #F5F5F5;
  200. border-color: #ffffff;
  201. border: none;
  202. }
  203. table.clsWarning
  204. {
  205. background: #ffffff;
  206. padding: 0px;
  207. margin: 0px;
  208. border: none;
  209. }
  210. table.clsWarning td
  211. {
  212. padding: 0px;
  213. margin: 0px;
  214. background: #ffffff;
  215. vertical-align: middle;
  216. font-size: 70%;
  217. }
  218. div#mainSection table
  219. {
  220. width: 95%;
  221. background: #ffffff;
  222. margin-top: 5px;
  223. margin-bottom: 5px;
  224. }
  225. div#mainSection table th
  226. {
  227. padding: 5px 6px;
  228. background: #EFEFF7;
  229. text-align: left;
  230. font-size: 70%;
  231. vertical-align: bottom;
  232. border-bottom: 1px solid #C8CDDE;
  233. }
  234. div#mainSection table td
  235. {
  236. padding: 5px 5px;
  237. background: #F7F7FF;
  238. vertical-align: top;
  239. font-size: 70%;
  240. border-bottom: 1px solid #D5D5D3;
  241. }
  242. div#syntaxCodeBlocks table th
  243. {
  244. padding: 1px 6px;
  245. color: #000066;
  246. }
  247. div#syntaxCodeBlocks table td
  248. {
  249. padding: 1px 5px;
  250. }
  251. /* Applies to the running header text in the first row of the upper table in the
  252. non-scrolling header region. */
  253. span#runningHeaderText
  254. {
  255. color: #003399;
  256. font-size: 90%;
  257. padding-left: 13;
  258. }
  259. /* Applies to the topic title in the second row of the upper table in the
  260. non-scrolling header region. */
  261. span#nsrTitle
  262. {
  263. color: #003399;
  264. font-size: 120%;
  265. font-weight: 600;
  266. padding-left: 13;
  267. }
  268. /* Applies to everything below the non-scrolling header region. */
  269. div#mainSection
  270. {
  271. font-size: 70%;
  272. width: 100%;
  273. }
  274. /* Applies to everything below the non-scrolling header region, minus the footer. */
  275. div#mainBody
  276. {
  277. font-size: 90%;
  278. margin-left: 15;
  279. margin-top: 10;
  280. padding-bottom: 20;
  281. }
  282. /* Adds right padding for all blocks in mainBody */
  283. div#mainBody p, div#mainBody ol, div#mainBody ul, div#mainBody dl
  284. {
  285. padding-right: 5;
  286. }
  287. div#mainBody div.alert, div#mainBody div.code, div#mainBody div.tableSection
  288. {
  289. width:98.9%;
  290. }
  291. div.alert p, div.code p
  292. {
  293. margin-top:5;
  294. margin-bottom:8;
  295. }
  296. /*- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - Begin Note Styles - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -*/
  297. div#mainSection div.alert table
  298. {
  299. border: 0;
  300. }
  301. div#mainSection div.alert table th
  302. {
  303. padding-top: 0;
  304. padding-bottom: 0;
  305. padding-left: 5;
  306. padding-right: 5;
  307. }
  308. div#mainSection div.alert table td
  309. {
  310. padding-left: 5;
  311. padding-right: 5;
  312. }
  313. img.note
  314. {
  315. border: 0;
  316. margin-left: 0;
  317. margin-right: 3;
  318. }
  319. /*- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - End Note Styles - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -*/
  320. /*- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - Begin Non-scrolling Header Region Styles - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -*/
  321. /* Applies to the entire non-scrolling header region. */
  322. div#header
  323. {
  324. background-color: #D4DFFF;
  325. padding-top: 0;
  326. padding-bottom: 0;
  327. padding-left: 0;
  328. padding-right: 0;
  329. width: 100%;
  330. }
  331. /* Applies to both tables in the non-scrolling header region. */
  332. div#header table
  333. {
  334. margin-top: 0;
  335. margin-bottom: 0;
  336. border-bottom-color: #C8CDDE;
  337. border-bottom-style: solid;
  338. border-bottom-width: 1;
  339. background: #D4DFFF;
  340. width: 100%;
  341. }
  342. /* Applies to cells in both tables in the non-scrolling header region. */
  343. div#header table td
  344. {
  345. color: #0000FF;
  346. font-size: 70%;
  347. padding-right: 20;
  348. padding-top: 1;
  349. padding-bottom: 1;
  350. border: none;
  351. background: #D4DFFF;
  352. }
  353. /* Applies to the last row in the upper table of the non-scrolling header region. Text
  354. in this row includes See Also, Constructors, Methods, and Properties. */
  355. div#header table tr#headerTableRow3 td
  356. {
  357. padding-bottom: 2;
  358. padding-top: 5;
  359. padding-left: 15;
  360. }
  361. /* Applies to the lower table in the non-scrolling header region. Text in this table
  362. includes Collapse All/Expand All, Language Filter, and Members Options. */
  363. div#header table#bottomTable
  364. {
  365. border-top-color: #FFFFFF;
  366. border-top-style: solid;
  367. border-top-width: 1;
  368. text-align: left;
  369. padding-left: 15;
  370. }
  371. blockquote
  372. {
  373. margin-left: 3.8em;
  374. margin-right: 3.8em;
  375. margin-top: .6em;
  376. margin-bottom: .6em;
  377. }
  378. sup
  379. {
  380. text-decoration: none;
  381. font-size: smaller;
  382. }
  383. a:link
  384. {
  385. color: #0000FF;
  386. /* font-weight: bold */
  387. }
  388. a:visited
  389. {
  390. color: #0000AA;
  391. /* font-weight: bold */
  392. }
  393. a:hover
  394. {
  395. color: #3366FF;
  396. /* font-weight: bold */
  397. }
  398. .label
  399. {
  400. font-weight: bold;
  401. margin-top: 1em;
  402. margin-left: -26px;
  403. }
  404. .tl
  405. {
  406. margin-bottom: .75em;
  407. }
  408. .atl
  409. {
  410. padding-left: 1.5em;
  411. padding-bottom: .75em;
  412. }
  413. .cfe
  414. {
  415. font-weight: bold;
  416. }
  417. .mini
  418. {
  419. font-size: smaller;
  420. }
  421. .dt
  422. {
  423. margin-bottom: -.6em;
  424. }
  425. .indent
  426. {
  427. margin-left: 1.9em;
  428. margin-right: 1.9em;
  429. }
  430. .product
  431. {
  432. text-align: right;
  433. color: #333333;
  434. font-size: smaller;
  435. font-style: italic;
  436. }
  437. .buttonbarshade
  438. {
  439. position: relative;
  440. margin: 0;
  441. left: 0px;
  442. top: 2;
  443. width: 50%;
  444. height: 40px;
  445. }
  446. .buttonbartable
  447. {
  448. position: absolute;
  449. margin: 0;
  450. padding:0;
  451. border:0;
  452. left:0px;
  453. top: 2;
  454. width: 100%;
  455. height: 40px;
  456. }
  457. /* background color, font for header */
  458. table.buttonbartable td, table.buttonbarshade td
  459. {
  460. background: #ffffff; /*#5177B8; #80C615;*/
  461. border-left: 0px solid #80C615;
  462. margin: 0;
  463. padding: 0px 0px 0px 0px;
  464. font-family: Impact, sans-serif;
  465. font-size: 14pt;
  466. }
  467. table.buttonbartable td.button1
  468. {
  469. background: #5177B8; /*#80C615;*/;
  470. padding: 0;
  471. font-weight: bold;
  472. text-align: center;
  473. cursor: hand;
  474. }
  475. table.buttonbartable td.button2
  476. {
  477. background: #5177B8; /*#80C615;*/;
  478. font-weight: bold;
  479. text-align: center;
  480. }
  481. table.buttonbartable td.button3
  482. {
  483. background: #5177B8; /*#80C615;*/;
  484. font-weight: bold;
  485. text-align: center;
  486. }
  487. table.buttonbartable td.runninghead
  488. {
  489. padding-left: 0px;
  490. font-style: italic;
  491. text-align: left;
  492. }
  493. .version
  494. {
  495. text-align: left;
  496. color: #000000;
  497. margin-top: 3em;
  498. margin-left: -26px;
  499. font-size: smaller;
  500. font-style: italic;
  501. }
  502. .lang, .ilang
  503. {
  504. color: #0000ff;
  505. font: normal 7pt Arial, Helvetica, sans-serif;
  506. }
  507. div.langMenu
  508. {
  509. position: absolute;
  510. z-index: 1;
  511. width: 96pt;
  512. padding: 8pt;
  513. visibility: hidden;
  514. border: 1px solid #000000;
  515. background: #ffffd0;
  516. }
  517. div.langMenu ul
  518. {
  519. padding-left: 2em;
  520. margin-left: 0;
  521. }
  522. div.filtered
  523. {
  524. margin: 4pt 0 8pt -26px;
  525. padding: 4px 4px 8px 26px;
  526. width: 100%;
  527. border: 2px solid #aaaacc;
  528. background: #ffffff;
  529. }
  530. div.filtered2
  531. {
  532. margin: 4pt 0 8pt -26px;
  533. padding: 4px 4px 8px 26px;
  534. width: 100%;
  535. border: none;
  536. background: #ffffff;
  537. }
  538. div.filtered h1, div.filtered h2, div.filtered h3, div.filtered h4
  539. {
  540. margin-left: -22px;
  541. }
  542. div.filtered span.lang
  543. {
  544. position: relative;
  545. left: -22px;
  546. }
  547. div.reftip
  548. {
  549. position: absolute;
  550. z-index: 1;
  551. padding: 8pt;
  552. visibility: hidden;
  553. border: 1px solid #000000;
  554. background: #ffffd0;
  555. }
  556. a.synParam
  557. {
  558. color: #0000FF;
  559. /*color: #3F7800;*/
  560. /*color: #8DC54F;*/
  561. text-decoration: none;
  562. font-weight: normal;
  563. }
  564. a.synParam:hover
  565. {
  566. text-decoration: underline;
  567. font-weight: normal;
  568. }
  569. div.sapop
  570. {
  571. position: absolute;
  572. z-index: 1;
  573. left: 26px;
  574. width: 100%;
  575. padding: 10px 10px 10px 36px;
  576. visibility: hidden;
  577. border: 1px solid #000000;
  578. background: #ffffd0;
  579. }
  580. div.footer
  581. {
  582. width: 100%;
  583. border: none;
  584. background: #ffffff;
  585. margin-top: 18pt;
  586. padding-bottom: 12pt;
  587. color: #0000FF;
  588. /*color: #228B22; */
  589. text-align: center;
  590. font-size: 76%;
  591. }
  592. div.preliminary
  593. {
  594. margin-top: 8pt;
  595. padding-bottom: 12pt;
  596. color: #A0A0A0;
  597. }
  598. /* A procedure section. eg. 'To create a file', 'To add a value' */
  599. div.proc
  600. {
  601. margin-left: 0.5em;
  602. }
  603. /* The title of a 'procedure' section. */
  604. div.proc h3
  605. {
  606. font-family: Verdana, Arial, Helvetica, sans-serif;
  607. font-weight: bold;
  608. font-size: 115%;
  609. margin-top: 1em;
  610. margin-bottom: 0.4em;
  611. margin-left: -0.5em;
  612. color: #003399;
  613. }
  614. div.proc ul
  615. {
  616. margin-left: 1.5em;
  617. }
  618. div.proc ol
  619. {
  620. margin-left: 2.0em;
  621. }
  622. .note
  623. {
  624. margin-left: 14pt;
  625. margin-right: 12pt;
  626. }
  627. .indent1
  628. {
  629. margin-left: 12pt;
  630. }
  631. .indent2
  632. {
  633. margin-left: 24pt;
  634. }
  635. .indent3
  636. {
  637. margin-left: 36pt;
  638. }
  639. p.proch
  640. {
  641. padding-left: 16px;
  642. }
  643. p.proch img
  644. {
  645. position: relative;
  646. vertical-align: top;
  647. left: -18px;
  648. margin-right: -14px;
  649. margin-bottom: -18px;
  650. }
  651. div.clsPlatSpec
  652. {
  653. background-color:#FFF8DC;
  654. border-style:solid;
  655. border-width:1pt 0pt 0pt 1pt;
  656. border-color:#ffE4C4;
  657. margin-top:0.6em;
  658. width:100%;
  659. }
  660. /* Applies to the language labels in the Language Filter drop-down list. */
  661. .languageFilter
  662. {
  663. color: #0000FF;
  664. cursor:hand;
  665. text-decoration:underline;
  666. padding-bottom:4;
  667. }
  668. /* Dropdown areas */
  669. #languageSpan {
  670. position: absolute;
  671. visibility: hidden;
  672. border-style: solid;
  673. border-width: 1px;
  674. border-color: #C8CDDE;
  675. background: #d4dfff;
  676. padding: 4px;
  677. font-size: 70%;
  678. }
  679. #membersOptionsSpan {
  680. position: absolute;
  681. visibility: hidden;
  682. border-style: solid;
  683. border-width: 1px;
  684. border-color: #C8CDDE;
  685. background: #d4dfff;
  686. padding: 4px;
  687. font-size: 70%;
  688. }
  689. --></style>
  690. <xml>
  691. <MSHelp:TOCTitle Title="Simple Animation Sample" />
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  702. <h1>Simple Animation Sample</h1>
  703. This sample shows you how to apply simple program-controlled, rigid-body animation to a model rendered using the XNA Framework.
  704. <a id="ID2EK" name="ID2EK"> </a><h1 class="heading">Sample Overview</h1><div id="ID2EK" class="hxnx1">
  705. <p>A tank model is loaded through the Content Pipeline, and then rendered using a program-controlled animation. The wheels turn, the turret swivels back and forth, and the hatch opens and closes.</p>
  706. </div>
  707. <a id="ID2ER" name="ID2ER"> </a><h1 class="heading">How the Sample Works</h1><div id="ID2ER" class="hxnx1">
  708. <p>This sample begins by loading a tank model. The tank is built of a hierarchy of separate meshes. The wheels, the turret, the hatch, and so on, are all separate meshes. Inside the 3D modeling package, each mesh has a descriptive name. Each is attached to the appropriate parent mesh with a suitable pivot point. For example, the cannon mesh can tilt up and down. It is attached to the turret mesh, which can also swivel from left to right, and is itself attached to the body of the tank. Because of this hierarchy, when you rotate the turret, the cannon rotates along with it.</p>
  709. <img src="Model-ModelMesh.png" />
  710. <p>
  711. In the XNA Framework, the <a href="http://msdn.microsoft.com/en-us/library/microsoft.xna.framework.graphics.model.aspx">Model</a> class represents the whole model. The <a href="http://msdn.microsoft.com/en-us/library/microsoft.xna.framework.graphics.model.aspx">Model</a> contains a <a href="http://msdn.microsoft.com/en-us/library/microsoft.xna.framework.graphics.modelmesh.aspx">ModelMesh</a> for each separate mesh in the model. Each <a href="http://msdn.microsoft.com/en-us/library/microsoft.xna.framework.graphics.modelmesh.aspx">ModelMesh</a> contains a <a href="http://msdn.microsoft.com/en-us/library/microsoft.xna.framework.graphics.modelmesh.parentbone.aspx">ParentBone</a> (the pivot point mentioned earlier), which controls the mesh's position and orientation relative to the model. The <a href="http://msdn.microsoft.com/en-us/library/microsoft.xna.framework.graphics.model.aspx">Model</a> has a <a href="http://msdn.microsoft.com/en-us/library/microsoft.xna.framework.graphics.model.root.aspx">Root</a> bone, which determines the model's position and orientation. Every <a href="http://msdn.microsoft.com/en-us/library/microsoft.xna.framework.graphics.modelbone.aspx">ModelBone</a> can have one parent and many children. The <a href="http://msdn.microsoft.com/en-us/library/microsoft.xna.framework.graphics.model.root.aspx">Root</a> bone on the <a href="http://msdn.microsoft.com/en-us/library/microsoft.xna.framework.graphics.model.aspx">Model</a> object is the ultimate parent; its children are bones on <a href="http://msdn.microsoft.com/en-us/library/microsoft.xna.framework.graphics.modelmesh.aspx">ModelMesh</a> objects, which might have other <a href="http://msdn.microsoft.com/en-us/library/microsoft.xna.framework.graphics.modelmesh.aspx">ModelMesh</a> bones as their children, and so on. In the example above, the body of the tank would have a <a href="http://msdn.microsoft.com/en-us/library/microsoft.xna.framework.graphics.modelmesh.parentbone.aspx">ParentBone</a>, with a child bone for the turret, which itself has a child bone for the cannon. In any given family of bones, rotating the parent bone also rotates the children, and their children, and so on.
  712. </p>
  713. <p>
  714. Every bone has a transformation matrix (called <a href="http://msdn.microsoft.com/en-us/library/microsoft.xna.framework.graphics.modelbone.transform.aspx">Transform</a>) that defines its position and rotation relative to the position of the parent bone. This rotation and translation applies to all the vertices in the <a href="http://msdn.microsoft.com/en-us/library/microsoft.xna.framework.graphics.modelmesh.aspx">ModelMesh</a> (for example, all the vertices that connect to that bone). To animate a bone, you multiply the default bone transform by a new matrix. When you draw the <a href="http://msdn.microsoft.com/en-us/library/microsoft.xna.framework.graphics.modelmesh.aspx">ModelMesh</a>, you then base your world matrix on the bone's transform.
  715. </p>
  716. <p>
  717. The easiest way to incorporate transformed bones into drawing is to use the <a href="http://msdn.microsoft.com/en-us/library/microsoft.xna.framework.graphics.model.copyabsolutebonetransformsto.aspx">CopyAbsoluteBoneTransformsTo</a> method. This method takes the bone transforms, which are relative to each other, and iterates over them to make them relative to the <a href="http://msdn.microsoft.com/en-us/library/microsoft.xna.framework.graphics.model.root.aspx">Root</a> bone of the <a href="http://msdn.microsoft.com/en-us/library/microsoft.xna.framework.graphics.model.aspx">Model</a>. It then returns a copy of these transforms. When you draw each <a href="http://msdn.microsoft.com/en-us/library/microsoft.xna.framework.graphics.modelmesh.aspx">ModelMesh</a>, you can use the absolute bone transform as the first part of your world matrix. This way you won't have to worry about parent bones and their relationships.
  718. </p>
  719. <p>
  720. The <b>Tank</b> class is a wrapper around the XNA Framework <a href="http://msdn.microsoft.com/en-us/library/microsoft.xna.framework.graphics.model.aspx">Model</a> type. It exposes properties for each value that can be used to animate the tank. In the <MSHelp:link keywords="M:Microsoft.Xna.Framework.Content.ContentManager.Load" tabindex="0">Load</MSHelp:link> method, it uses the <a href="http://msdn.microsoft.com/en-us/library/microsoft.xna.framework.content.contentmanager.aspx">ContentManager</a> to load the underlying <a href="http://msdn.microsoft.com/en-us/library/microsoft.xna.framework.graphics.model.aspx">Model</a> data. Then it saves shortcut references to the bones that are going to be animated, and stores their original transform matrices. In the <a href="http://msdn.microsoft.com/en-us/library/microsoft.xna.framework.game.draw.aspx">Draw</a> method, it computes new rotation matrices based on new rotation values from the game. These new matrices are assigned to the <a href="http://msdn.microsoft.com/en-us/library/microsoft.xna.framework.graphics.modelbone.transform.aspx">Transform</a> properties of the animated bones, after which the model is rendered in the usual way by using <a href="http://msdn.microsoft.com/en-us/library/microsoft.xna.framework.graphics.model.copyabsolutebonetransformsto.aspx">CopyAbsoluteBoneTransformsTo</a>.
  721. </p>
  722. <p>
  723. The <b>SimpleAnimation</b> game uses the current time value to update the animation properties on the <b>Tank</b> object. The wheels are rotated, while the other values are moved back and forth in sine curves of varying speeds. In a real game, you would take this data from user inputs or the physics system rather than just making everything oscillates.
  724. </p>
  725. </div>
  726. </div><div class="footer" id="footer"><p>© 2010 Microsoft Corporation. All rights reserved.<br />Send feedback to <a href="mailto:[email protected]?subject=Documentation Feedback: Simple Animation Sample">[email protected]</a>.</p></div></div></body></html>