ShatterEffect.htm 18 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>Shatter Effect Sample</title>
  2. <style><!--
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  4. * SCRIPT-SUPPORTING STYLES
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  234. div#mainSection table td
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  242. div#syntaxCodeBlocks table th
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  245. color: #000066;
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  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. {
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  300. }
  301. div#mainSection div.alert table th
  302. {
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  304. padding-bottom: 0;
  305. padding-left: 5;
  306. padding-right: 5;
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  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;
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  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. {
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  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
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  510. z-index: 1;
  511. width: 96pt;
  512. padding: 8pt;
  513. visibility: hidden;
  514. border: 1px solid #000000;
  515. background: #ffffd0;
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  517. div.langMenu ul
  518. {
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  520. margin-left: 0;
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  522. div.filtered
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  524. margin: 4pt 0 8pt -26px;
  525. padding: 4px 4px 8px 26px;
  526. width: 100%;
  527. border: 2px solid #aaaacc;
  528. background: #ffffff;
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  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;
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  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;
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  701. </head><body><div id="mainSection"><div id="mainBody">
  702. <h1>Shatter Effect Sample</h1>
  703. This sample shows how you can apply an effect on any model in your game to shatter it apart. The effect is simulated with a vertex shader.
  704. <a id="ID2EK" name="ID2EK"> </a><h1 class="heading">Sample Overview</h1><div id="ID2EK" class="hxnx1">
  705. <p>
  706. The shatter effect operates independently on every triangle in the model. For every triangle in the model, the vertex shader rotates the vertices of the triangle around the x, y, and z axes by random velocities. At the same time, the triangle is translated along its normal. This creates the appearance of the entire model shattering outwards into small pieces. To get this effect to work properly, the model must be processed beforehand with a custom processor that derives from <a href="http://msdn.microsoft.com/en-us/library/microsoft.xna.framework.content.pipeline.processors.modelprocessor.aspx">ModelProcessor</a>.
  707. </p>
  708. <a id="ID2EU" name="ID2EU"> </a><h2 class="subHeading">Sample Controls</h2><div id="ID2EU" class="hxnx2">
  709. <p>This sample uses the following keyboard and gamepad controls.</p>
  710. <table>
  711. <tr>
  712. <th>Action</th>
  713. <th>Keyboard control</th>
  714. <th>Gamepad control</th>
  715. </tr>
  716. <tr>
  717. <td>Shatter the model</td>
  718. <td>UP ARROW</td>
  719. <td>
  720. <b>A</b>
  721. </td>
  722. </tr>
  723. <tr>
  724. <td>Reverse the shatter effect</td>
  725. <td>DOWN ARROW</td>
  726. <td>
  727. <b>B</b>
  728. </td>
  729. </tr>
  730. <tr>
  731. <td>Exit the sample</td>
  732. <td>ESC or ALT+F4</td>
  733. <td>
  734. <b>BACK</b>
  735. </td>
  736. </tr>
  737. </table>
  738. </div>
  739. </div>
  740. <a id="ID2EMC" name="ID2EMC"> </a><h1 class="heading">How the Sample Works</h1><div id="ID2EMC" class="hxnx1">
  741. <p>The shatter effect is achieved with the help of both a processor and an effect.</p>
  742. <a id="ID2ESC" name="ID2ESC"> </a><h2 class="subHeading">Build Time Processing</h2><div id="ID2ESC" class="hxnx2">
  743. <p>
  744. The processor, ShatterProcessor, is derived from <b>ModelProcessor</b> and overrides the <b>Process</b> method. The processor manipulates the model’s data in three ways before passing it to <b>ModelProcessor</b> to produce the processor’s final output.
  745. </p>
  746. <a id="ID2E6C" name="ID2E6C"> </a><h4 class="subHeading">
  747. 1.  Break down the model’s triangles
  748. </h4><div id="ID2E6C" class="hxnx3">
  749. <p>This step reverses the effect of indexing a model’s vertices to break up the triangles. While it will increase the number of vertices for the model on the GPU, this is required so that we can independently manipulate every triangle without affecting nearby ones. An indexed model does not give us such freedom.</p>
  750. </div>
  751. <a id="ID2EJD" name="ID2EJD"> </a><h4 class="subHeading">
  752. 2.  Calculate the center point of every triangle in the model
  753. </h4><div id="ID2EJD" class="hxnx3">
  754. <p>Once the model’s triangles have been broken down, the processor calculates the center point of every triangle using the formula:</p>
  755. <pre>
  756. TriangleCenter = (<i>Vertex_1</i> + <i>Vertex_2</i> + <i>Vertex_3</i>) / 3
  757. </pre>
  758. <p>
  759. The triangle centers are then saved in a <b>Vector3</b>[] array. For every triangle in the model, the triangle center is used in the vertex shader as the point to rotate the triangle around.
  760. </p>
  761. </div>
  762. <a id="ID2EBE" name="ID2EBE"> </a><h4 class="subHeading">
  763. 3.  Create two vertex channels for the model
  764. </h4><div id="ID2EBE" class="hxnx3">
  765. <p>
  766. Now that the triangle centers have been calculated, the processor creates a per-vertex channel to store them. For every three vertices, we store the triangle center that corresponds to the triangle they form. The channel is called <code>triangleCenterChannel</code>. This channel adds a <b>float3 TEXCOORD1</b> field to the vertex declaration for the vertex shader to use. The channel is created with the help of a helper function called <code>ReplicateTriangleDataToEachVertex</code>. This function uses the <b>Vector3</b>[] array created earlier and returns the corresponding center for every vertex in the model.
  767. </p>
  768. <p>
  769. The second channel the processor creates is called <code>rotationalVelocityChannel</code>. This channel creates a <b>float3 TEXCOORD2</b> field in the vertex declaration for the model. For every vertex, the processor generates a random set of x, y, and z velocities in the range of –1 to 1. The vertex shader uses these values to determine how to rotate each vertex as the model is shattered.
  770. </p>
  771. <p>
  772. The processor then passes the newly created model to the parent processor, <b>ModelProcessor</b>, to complete processing it.
  773. </p>
  774. </div>
  775. </div>
  776. </div>
  777. <a id="ID2EEF" name="ID2EEF"> </a><h1 class="heading">Extending the Sample</h1><div id="ID2EEF" class="hxnx1">
  778. <p>The sample can be extended in a variety of ways.</p>
  779. <ul>
  780. <li>The effect could simulate wind drag for every triangle based on its size, so that bigger triangles fall a bit slower than smaller ones. Create another vertex channel containing information about triangle size and precalculate the channel at processing time.</li>
  781. <li>Group together chunks of triangles that are close to each other and rotate/translate them as a single entity. This gives the illusion of chunks of the model breaking versus smaller pieces.</li>
  782. </ul>
  783. </div>
  784. </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: Shatter Effect Sample">[email protected]</a>.</p></div></div></body></html>