🛠️🐜 Antkeeper superbuild with dependencies included https://antkeeper.com
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  6. <meta name="description" content="API Reference Documentation for FreeType-2.11.0">
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  23. <label class="md-overlay" for="__drawer"></label>
  24. <div data-md-component="skip">
  25. <a href="#computations" class="md-skip">
  26. Skip to content
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  41. <div class="md-header__topic">
  42. <span class="md-ellipsis">
  43. FreeType-2.11.0 API Reference
  44. </span>
  45. </div>
  46. <div class="md-header__topic" data-md-component="header-topic">
  47. <span class="md-ellipsis">
  48. Computations
  49. </span>
  50. </div>
  51. </div>
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  56. <div class="md-search" data-md-component="search" role="dialog">
  57. <label class="md-search__overlay" for="__search"></label>
  58. <div class="md-search__inner" role="search">
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  70. <div class="md-search__scrollwrap" data-md-scrollfix>
  71. <div class="md-search-result" data-md-component="search-result">
  72. <div class="md-search-result__meta">
  73. Initializing search
  74. </div>
  75. <ol class="md-search-result__list"></ol>
  76. </div>
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  78. </div>
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  80. </div>
  81. </nav>
  82. </header>
  83. <div class="md-container" data-md-component="container">
  84. <main class="md-main" data-md-component="main">
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  86. <div class="md-sidebar md-sidebar--primary" data-md-component="sidebar" data-md-type="navigation" >
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  90. <label class="md-nav__title" for="__drawer">
  91. <a href="index.html" title="FreeType-2.11.0 API Reference" class="md-nav__button md-logo" aria-label="FreeType-2.11.0 API Reference" data-md-component="logo">
  92. <img src="images/favico.ico" alt="logo">
  93. </a>
  94. FreeType-2.11.0 API Reference
  95. </label>
  96. <ul class="md-nav__list" data-md-scrollfix>
  97. <li class="md-nav__item">
  98. <a href="index.html" class="md-nav__link">
  99. TOC
  100. </a>
  101. </li>
  102. <li class="md-nav__item">
  103. <a href="ft2-index.html" class="md-nav__link">
  104. Index
  105. </a>
  106. </li>
  107. <li class="md-nav__item md-nav__item--nested">
  108. <input class="md-nav__toggle md-toggle" data-md-toggle="__nav_3" type="checkbox" id="__nav_3" >
  109. <label class="md-nav__link" for="__nav_3">
  110. General Remarks
  111. <span class="md-nav__icon md-icon"></span>
  112. </label>
  113. <nav class="md-nav" aria-label="General Remarks" data-md-level="1">
  114. <label class="md-nav__title" for="__nav_3">
  115. <span class="md-nav__icon md-icon"></span>
  116. General Remarks
  117. </label>
  118. <ul class="md-nav__list" data-md-scrollfix>
  119. <li class="md-nav__item">
  120. <a href="ft2-preamble.html" class="md-nav__link">
  121. Preamble
  122. </a>
  123. </li>
  124. <li class="md-nav__item">
  125. <a href="ft2-header_inclusion.html" class="md-nav__link">
  126. FreeType's header inclusion scheme
  127. </a>
  128. </li>
  129. <li class="md-nav__item">
  130. <a href="ft2-user_allocation.html" class="md-nav__link">
  131. User allocation
  132. </a>
  133. </li>
  134. </ul>
  135. </nav>
  136. </li>
  137. <li class="md-nav__item md-nav__item--nested">
  138. <input class="md-nav__toggle md-toggle" data-md-toggle="__nav_4" type="checkbox" id="__nav_4" >
  139. <label class="md-nav__link" for="__nav_4">
  140. Core API
  141. <span class="md-nav__icon md-icon"></span>
  142. </label>
  143. <nav class="md-nav" aria-label="Core API" data-md-level="1">
  144. <label class="md-nav__title" for="__nav_4">
  145. <span class="md-nav__icon md-icon"></span>
  146. Core API
  147. </label>
  148. <ul class="md-nav__list" data-md-scrollfix>
  149. <li class="md-nav__item">
  150. <a href="ft2-version.html" class="md-nav__link">
  151. FreeType Version
  152. </a>
  153. </li>
  154. <li class="md-nav__item">
  155. <a href="ft2-basic_types.html" class="md-nav__link">
  156. Basic Data Types
  157. </a>
  158. </li>
  159. <li class="md-nav__item">
  160. <a href="ft2-base_interface.html" class="md-nav__link">
  161. Base Interface
  162. </a>
  163. </li>
  164. <li class="md-nav__item">
  165. <a href="ft2-glyph_variants.html" class="md-nav__link">
  166. Unicode Variation Sequences
  167. </a>
  168. </li>
  169. <li class="md-nav__item">
  170. <a href="ft2-color_management.html" class="md-nav__link">
  171. Glyph Color Management
  172. </a>
  173. </li>
  174. <li class="md-nav__item">
  175. <a href="ft2-layer_management.html" class="md-nav__link">
  176. Glyph Layer Management
  177. </a>
  178. </li>
  179. <li class="md-nav__item">
  180. <a href="ft2-glyph_management.html" class="md-nav__link">
  181. Glyph Management
  182. </a>
  183. </li>
  184. <li class="md-nav__item">
  185. <a href="ft2-mac_specific.html" class="md-nav__link">
  186. Mac Specific Interface
  187. </a>
  188. </li>
  189. <li class="md-nav__item">
  190. <a href="ft2-sizes_management.html" class="md-nav__link">
  191. Size Management
  192. </a>
  193. </li>
  194. <li class="md-nav__item">
  195. <a href="ft2-header_file_macros.html" class="md-nav__link">
  196. Header File Macros
  197. </a>
  198. </li>
  199. </ul>
  200. </nav>
  201. </li>
  202. <li class="md-nav__item md-nav__item--nested">
  203. <input class="md-nav__toggle md-toggle" data-md-toggle="__nav_5" type="checkbox" id="__nav_5" >
  204. <label class="md-nav__link" for="__nav_5">
  205. Format-Specific API
  206. <span class="md-nav__icon md-icon"></span>
  207. </label>
  208. <nav class="md-nav" aria-label="Format-Specific API" data-md-level="1">
  209. <label class="md-nav__title" for="__nav_5">
  210. <span class="md-nav__icon md-icon"></span>
  211. Format-Specific API
  212. </label>
  213. <ul class="md-nav__list" data-md-scrollfix>
  214. <li class="md-nav__item">
  215. <a href="ft2-multiple_masters.html" class="md-nav__link">
  216. Multiple Masters
  217. </a>
  218. </li>
  219. <li class="md-nav__item">
  220. <a href="ft2-truetype_tables.html" class="md-nav__link">
  221. TrueType Tables
  222. </a>
  223. </li>
  224. <li class="md-nav__item">
  225. <a href="ft2-type1_tables.html" class="md-nav__link">
  226. Type 1 Tables
  227. </a>
  228. </li>
  229. <li class="md-nav__item">
  230. <a href="ft2-sfnt_names.html" class="md-nav__link">
  231. SFNT Names
  232. </a>
  233. </li>
  234. <li class="md-nav__item">
  235. <a href="ft2-bdf_fonts.html" class="md-nav__link">
  236. BDF and PCF Files
  237. </a>
  238. </li>
  239. <li class="md-nav__item">
  240. <a href="ft2-cid_fonts.html" class="md-nav__link">
  241. CID Fonts
  242. </a>
  243. </li>
  244. <li class="md-nav__item">
  245. <a href="ft2-pfr_fonts.html" class="md-nav__link">
  246. PFR Fonts
  247. </a>
  248. </li>
  249. <li class="md-nav__item">
  250. <a href="ft2-winfnt_fonts.html" class="md-nav__link">
  251. Window FNT Files
  252. </a>
  253. </li>
  254. <li class="md-nav__item">
  255. <a href="ft2-font_formats.html" class="md-nav__link">
  256. Font Formats
  257. </a>
  258. </li>
  259. <li class="md-nav__item">
  260. <a href="ft2-gasp_table.html" class="md-nav__link">
  261. Gasp Table
  262. </a>
  263. </li>
  264. </ul>
  265. </nav>
  266. </li>
  267. <li class="md-nav__item md-nav__item--nested">
  268. <input class="md-nav__toggle md-toggle" data-md-toggle="__nav_6" type="checkbox" id="__nav_6" >
  269. <label class="md-nav__link" for="__nav_6">
  270. Controlling FreeType Modules
  271. <span class="md-nav__icon md-icon"></span>
  272. </label>
  273. <nav class="md-nav" aria-label="Controlling FreeType Modules" data-md-level="1">
  274. <label class="md-nav__title" for="__nav_6">
  275. <span class="md-nav__icon md-icon"></span>
  276. Controlling FreeType Modules
  277. </label>
  278. <ul class="md-nav__list" data-md-scrollfix>
  279. <li class="md-nav__item">
  280. <a href="ft2-auto_hinter.html" class="md-nav__link">
  281. The auto-hinter
  282. </a>
  283. </li>
  284. <li class="md-nav__item">
  285. <a href="ft2-cff_driver.html" class="md-nav__link">
  286. The CFF driver
  287. </a>
  288. </li>
  289. <li class="md-nav__item">
  290. <a href="ft2-t1_cid_driver.html" class="md-nav__link">
  291. The Type 1 and CID drivers
  292. </a>
  293. </li>
  294. <li class="md-nav__item">
  295. <a href="ft2-tt_driver.html" class="md-nav__link">
  296. The TrueType driver
  297. </a>
  298. </li>
  299. <li class="md-nav__item">
  300. <a href="ft2-pcf_driver.html" class="md-nav__link">
  301. The PCF driver
  302. </a>
  303. </li>
  304. <li class="md-nav__item">
  305. <a href="ft2-properties.html" class="md-nav__link">
  306. Driver properties
  307. </a>
  308. </li>
  309. <li class="md-nav__item">
  310. <a href="ft2-parameter_tags.html" class="md-nav__link">
  311. Parameter Tags
  312. </a>
  313. </li>
  314. <li class="md-nav__item">
  315. <a href="ft2-lcd_rendering.html" class="md-nav__link">
  316. Subpixel Rendering
  317. </a>
  318. </li>
  319. </ul>
  320. </nav>
  321. </li>
  322. <li class="md-nav__item md-nav__item--nested">
  323. <input class="md-nav__toggle md-toggle" data-md-toggle="__nav_7" type="checkbox" id="__nav_7" >
  324. <label class="md-nav__link" for="__nav_7">
  325. Cache Sub-System
  326. <span class="md-nav__icon md-icon"></span>
  327. </label>
  328. <nav class="md-nav" aria-label="Cache Sub-System" data-md-level="1">
  329. <label class="md-nav__title" for="__nav_7">
  330. <span class="md-nav__icon md-icon"></span>
  331. Cache Sub-System
  332. </label>
  333. <ul class="md-nav__list" data-md-scrollfix>
  334. <li class="md-nav__item">
  335. <a href="ft2-cache_subsystem.html" class="md-nav__link">
  336. Cache Sub-System
  337. </a>
  338. </li>
  339. </ul>
  340. </nav>
  341. </li>
  342. <li class="md-nav__item md-nav__item--active md-nav__item--nested">
  343. <input class="md-nav__toggle md-toggle" data-md-toggle="__nav_8" type="checkbox" id="__nav_8" checked>
  344. <label class="md-nav__link" for="__nav_8">
  345. Support API
  346. <span class="md-nav__icon md-icon"></span>
  347. </label>
  348. <nav class="md-nav" aria-label="Support API" data-md-level="1">
  349. <label class="md-nav__title" for="__nav_8">
  350. <span class="md-nav__icon md-icon"></span>
  351. Support API
  352. </label>
  353. <ul class="md-nav__list" data-md-scrollfix>
  354. <li class="md-nav__item md-nav__item--active">
  355. <input class="md-nav__toggle md-toggle" data-md-toggle="toc" type="checkbox" id="__toc">
  356. <label class="md-nav__link md-nav__link--active" for="__toc">
  357. Computations
  358. <span class="md-nav__icon md-icon"></span>
  359. </label>
  360. <a href="ft2-computations.html" class="md-nav__link md-nav__link--active">
  361. Computations
  362. </a>
  363. <nav class="md-nav md-nav--secondary" aria-label="Table of contents">
  364. <label class="md-nav__title" for="__toc">
  365. <span class="md-nav__icon md-icon"></span>
  366. Table of contents
  367. </label>
  368. <ul class="md-nav__list" data-md-component="toc" data-md-scrollfix>
  369. <li class="md-nav__item">
  370. <a href="#synopsis" class="md-nav__link">
  371. Synopsis
  372. </a>
  373. </li>
  374. <li class="md-nav__item">
  375. <a href="#ft_muldiv" class="md-nav__link">
  376. FT_MulDiv
  377. </a>
  378. </li>
  379. <li class="md-nav__item">
  380. <a href="#ft_mulfix" class="md-nav__link">
  381. FT_MulFix
  382. </a>
  383. </li>
  384. <li class="md-nav__item">
  385. <a href="#ft_divfix" class="md-nav__link">
  386. FT_DivFix
  387. </a>
  388. </li>
  389. <li class="md-nav__item">
  390. <a href="#ft_roundfix" class="md-nav__link">
  391. FT_RoundFix
  392. </a>
  393. </li>
  394. <li class="md-nav__item">
  395. <a href="#ft_ceilfix" class="md-nav__link">
  396. FT_CeilFix
  397. </a>
  398. </li>
  399. <li class="md-nav__item">
  400. <a href="#ft_floorfix" class="md-nav__link">
  401. FT_FloorFix
  402. </a>
  403. </li>
  404. <li class="md-nav__item">
  405. <a href="#ft_vector_transform" class="md-nav__link">
  406. FT_Vector_Transform
  407. </a>
  408. </li>
  409. <li class="md-nav__item">
  410. <a href="#ft_matrix_multiply" class="md-nav__link">
  411. FT_Matrix_Multiply
  412. </a>
  413. </li>
  414. <li class="md-nav__item">
  415. <a href="#ft_matrix_invert" class="md-nav__link">
  416. FT_Matrix_Invert
  417. </a>
  418. </li>
  419. <li class="md-nav__item">
  420. <a href="#ft_angle" class="md-nav__link">
  421. FT_Angle
  422. </a>
  423. </li>
  424. <li class="md-nav__item">
  425. <a href="#ft_angle_pi" class="md-nav__link">
  426. FT_ANGLE_PI
  427. </a>
  428. </li>
  429. <li class="md-nav__item">
  430. <a href="#ft_angle_2pi" class="md-nav__link">
  431. FT_ANGLE_2PI
  432. </a>
  433. </li>
  434. <li class="md-nav__item">
  435. <a href="#ft_angle_pi2" class="md-nav__link">
  436. FT_ANGLE_PI2
  437. </a>
  438. </li>
  439. <li class="md-nav__item">
  440. <a href="#ft_angle_pi4" class="md-nav__link">
  441. FT_ANGLE_PI4
  442. </a>
  443. </li>
  444. <li class="md-nav__item">
  445. <a href="#ft_sin" class="md-nav__link">
  446. FT_Sin
  447. </a>
  448. </li>
  449. <li class="md-nav__item">
  450. <a href="#ft_cos" class="md-nav__link">
  451. FT_Cos
  452. </a>
  453. </li>
  454. <li class="md-nav__item">
  455. <a href="#ft_tan" class="md-nav__link">
  456. FT_Tan
  457. </a>
  458. </li>
  459. <li class="md-nav__item">
  460. <a href="#ft_atan2" class="md-nav__link">
  461. FT_Atan2
  462. </a>
  463. </li>
  464. <li class="md-nav__item">
  465. <a href="#ft_angle_diff" class="md-nav__link">
  466. FT_Angle_Diff
  467. </a>
  468. </li>
  469. <li class="md-nav__item">
  470. <a href="#ft_vector_unit" class="md-nav__link">
  471. FT_Vector_Unit
  472. </a>
  473. </li>
  474. <li class="md-nav__item">
  475. <a href="#ft_vector_rotate" class="md-nav__link">
  476. FT_Vector_Rotate
  477. </a>
  478. </li>
  479. <li class="md-nav__item">
  480. <a href="#ft_vector_length" class="md-nav__link">
  481. FT_Vector_Length
  482. </a>
  483. </li>
  484. <li class="md-nav__item">
  485. <a href="#ft_vector_polarize" class="md-nav__link">
  486. FT_Vector_Polarize
  487. </a>
  488. </li>
  489. <li class="md-nav__item">
  490. <a href="#ft_vector_from_polar" class="md-nav__link">
  491. FT_Vector_From_Polar
  492. </a>
  493. </li>
  494. </ul>
  495. </nav>
  496. </li>
  497. <li class="md-nav__item">
  498. <a href="ft2-list_processing.html" class="md-nav__link">
  499. List Processing
  500. </a>
  501. </li>
  502. <li class="md-nav__item">
  503. <a href="ft2-outline_processing.html" class="md-nav__link">
  504. Outline Processing
  505. </a>
  506. </li>
  507. <li class="md-nav__item">
  508. <a href="ft2-quick_advance.html" class="md-nav__link">
  509. Quick retrieval of advance values
  510. </a>
  511. </li>
  512. <li class="md-nav__item">
  513. <a href="ft2-bitmap_handling.html" class="md-nav__link">
  514. Bitmap Handling
  515. </a>
  516. </li>
  517. <li class="md-nav__item">
  518. <a href="ft2-raster.html" class="md-nav__link">
  519. Scanline Converter
  520. </a>
  521. </li>
  522. <li class="md-nav__item">
  523. <a href="ft2-glyph_stroker.html" class="md-nav__link">
  524. Glyph Stroker
  525. </a>
  526. </li>
  527. <li class="md-nav__item">
  528. <a href="ft2-system_interface.html" class="md-nav__link">
  529. System Interface
  530. </a>
  531. </li>
  532. <li class="md-nav__item">
  533. <a href="ft2-module_management.html" class="md-nav__link">
  534. Module Management
  535. </a>
  536. </li>
  537. <li class="md-nav__item">
  538. <a href="ft2-gzip.html" class="md-nav__link">
  539. GZIP Streams
  540. </a>
  541. </li>
  542. <li class="md-nav__item">
  543. <a href="ft2-lzw.html" class="md-nav__link">
  544. LZW Streams
  545. </a>
  546. </li>
  547. <li class="md-nav__item">
  548. <a href="ft2-bzip2.html" class="md-nav__link">
  549. BZIP2 Streams
  550. </a>
  551. </li>
  552. <li class="md-nav__item">
  553. <a href="ft2-debugging_apis.html" class="md-nav__link">
  554. External Debugging APIs
  555. </a>
  556. </li>
  557. </ul>
  558. </nav>
  559. </li>
  560. <li class="md-nav__item md-nav__item--nested">
  561. <input class="md-nav__toggle md-toggle" data-md-toggle="__nav_9" type="checkbox" id="__nav_9" >
  562. <label class="md-nav__link" for="__nav_9">
  563. Error Codes
  564. <span class="md-nav__icon md-icon"></span>
  565. </label>
  566. <nav class="md-nav" aria-label="Error Codes" data-md-level="1">
  567. <label class="md-nav__title" for="__nav_9">
  568. <span class="md-nav__icon md-icon"></span>
  569. Error Codes
  570. </label>
  571. <ul class="md-nav__list" data-md-scrollfix>
  572. <li class="md-nav__item">
  573. <a href="ft2-error_enumerations.html" class="md-nav__link">
  574. Error Enumerations
  575. </a>
  576. </li>
  577. <li class="md-nav__item">
  578. <a href="ft2-error_code_values.html" class="md-nav__link">
  579. Error Code Values
  580. </a>
  581. </li>
  582. </ul>
  583. </nav>
  584. </li>
  585. <li class="md-nav__item md-nav__item--nested">
  586. <input class="md-nav__toggle md-toggle" data-md-toggle="__nav_10" type="checkbox" id="__nav_10" >
  587. <label class="md-nav__link" for="__nav_10">
  588. Miscellaneous
  589. <span class="md-nav__icon md-icon"></span>
  590. </label>
  591. <nav class="md-nav" aria-label="Miscellaneous" data-md-level="1">
  592. <label class="md-nav__title" for="__nav_10">
  593. <span class="md-nav__icon md-icon"></span>
  594. Miscellaneous
  595. </label>
  596. <ul class="md-nav__list" data-md-scrollfix>
  597. <li class="md-nav__item">
  598. <a href="ft2-gx_validation.html" class="md-nav__link">
  599. TrueTypeGX/AAT Validation
  600. </a>
  601. </li>
  602. <li class="md-nav__item">
  603. <a href="ft2-incremental.html" class="md-nav__link">
  604. Incremental Loading
  605. </a>
  606. </li>
  607. <li class="md-nav__item">
  608. <a href="ft2-truetype_engine.html" class="md-nav__link">
  609. The TrueType Engine
  610. </a>
  611. </li>
  612. <li class="md-nav__item">
  613. <a href="ft2-ot_validation.html" class="md-nav__link">
  614. OpenType Validation
  615. </a>
  616. </li>
  617. </ul>
  618. </nav>
  619. </li>
  620. </ul>
  621. </nav>
  622. </div>
  623. </div>
  624. </div>
  625. <div class="md-sidebar md-sidebar--secondary" data-md-component="sidebar" data-md-type="toc" >
  626. <div class="md-sidebar__scrollwrap">
  627. <div class="md-sidebar__inner">
  628. <nav class="md-nav md-nav--secondary" aria-label="Table of contents">
  629. <label class="md-nav__title" for="__toc">
  630. <span class="md-nav__icon md-icon"></span>
  631. Table of contents
  632. </label>
  633. <ul class="md-nav__list" data-md-component="toc" data-md-scrollfix>
  634. <li class="md-nav__item">
  635. <a href="#synopsis" class="md-nav__link">
  636. Synopsis
  637. </a>
  638. </li>
  639. <li class="md-nav__item">
  640. <a href="#ft_muldiv" class="md-nav__link">
  641. FT_MulDiv
  642. </a>
  643. </li>
  644. <li class="md-nav__item">
  645. <a href="#ft_mulfix" class="md-nav__link">
  646. FT_MulFix
  647. </a>
  648. </li>
  649. <li class="md-nav__item">
  650. <a href="#ft_divfix" class="md-nav__link">
  651. FT_DivFix
  652. </a>
  653. </li>
  654. <li class="md-nav__item">
  655. <a href="#ft_roundfix" class="md-nav__link">
  656. FT_RoundFix
  657. </a>
  658. </li>
  659. <li class="md-nav__item">
  660. <a href="#ft_ceilfix" class="md-nav__link">
  661. FT_CeilFix
  662. </a>
  663. </li>
  664. <li class="md-nav__item">
  665. <a href="#ft_floorfix" class="md-nav__link">
  666. FT_FloorFix
  667. </a>
  668. </li>
  669. <li class="md-nav__item">
  670. <a href="#ft_vector_transform" class="md-nav__link">
  671. FT_Vector_Transform
  672. </a>
  673. </li>
  674. <li class="md-nav__item">
  675. <a href="#ft_matrix_multiply" class="md-nav__link">
  676. FT_Matrix_Multiply
  677. </a>
  678. </li>
  679. <li class="md-nav__item">
  680. <a href="#ft_matrix_invert" class="md-nav__link">
  681. FT_Matrix_Invert
  682. </a>
  683. </li>
  684. <li class="md-nav__item">
  685. <a href="#ft_angle" class="md-nav__link">
  686. FT_Angle
  687. </a>
  688. </li>
  689. <li class="md-nav__item">
  690. <a href="#ft_angle_pi" class="md-nav__link">
  691. FT_ANGLE_PI
  692. </a>
  693. </li>
  694. <li class="md-nav__item">
  695. <a href="#ft_angle_2pi" class="md-nav__link">
  696. FT_ANGLE_2PI
  697. </a>
  698. </li>
  699. <li class="md-nav__item">
  700. <a href="#ft_angle_pi2" class="md-nav__link">
  701. FT_ANGLE_PI2
  702. </a>
  703. </li>
  704. <li class="md-nav__item">
  705. <a href="#ft_angle_pi4" class="md-nav__link">
  706. FT_ANGLE_PI4
  707. </a>
  708. </li>
  709. <li class="md-nav__item">
  710. <a href="#ft_sin" class="md-nav__link">
  711. FT_Sin
  712. </a>
  713. </li>
  714. <li class="md-nav__item">
  715. <a href="#ft_cos" class="md-nav__link">
  716. FT_Cos
  717. </a>
  718. </li>
  719. <li class="md-nav__item">
  720. <a href="#ft_tan" class="md-nav__link">
  721. FT_Tan
  722. </a>
  723. </li>
  724. <li class="md-nav__item">
  725. <a href="#ft_atan2" class="md-nav__link">
  726. FT_Atan2
  727. </a>
  728. </li>
  729. <li class="md-nav__item">
  730. <a href="#ft_angle_diff" class="md-nav__link">
  731. FT_Angle_Diff
  732. </a>
  733. </li>
  734. <li class="md-nav__item">
  735. <a href="#ft_vector_unit" class="md-nav__link">
  736. FT_Vector_Unit
  737. </a>
  738. </li>
  739. <li class="md-nav__item">
  740. <a href="#ft_vector_rotate" class="md-nav__link">
  741. FT_Vector_Rotate
  742. </a>
  743. </li>
  744. <li class="md-nav__item">
  745. <a href="#ft_vector_length" class="md-nav__link">
  746. FT_Vector_Length
  747. </a>
  748. </li>
  749. <li class="md-nav__item">
  750. <a href="#ft_vector_polarize" class="md-nav__link">
  751. FT_Vector_Polarize
  752. </a>
  753. </li>
  754. <li class="md-nav__item">
  755. <a href="#ft_vector_from_polar" class="md-nav__link">
  756. FT_Vector_From_Polar
  757. </a>
  758. </li>
  759. </ul>
  760. </nav>
  761. </div>
  762. </div>
  763. </div>
  764. <div class="md-content" data-md-component="content">
  765. <article class="md-content__inner md-typeset">
  766. <p><a href="https://www.freetype.org">FreeType</a> &raquo; <a href="../">Docs</a> &raquo; <a href="index.html#support-api">Support API</a> &raquo; Computations</p>
  767. <hr />
  768. <h1 id="computations">Computations<a class="headerlink" href="#computations" title="Permanent link">&para;</a></h1>
  769. <h2 id="synopsis">Synopsis<a class="headerlink" href="#synopsis" title="Permanent link">&para;</a></h2>
  770. <p>This section contains various functions used to perform computations on 16.16 fixed-float numbers or 2d vectors.</p>
  771. <p><strong>Attention</strong>: Most arithmetic functions take <code>FT_Long</code> as arguments. For historical reasons, FreeType was designed under the assumption that <code>FT_Long</code> is a 32-bit integer; results can thus be undefined if the arguments don't fit into 32 bits.</p>
  772. <h2 id="ft_muldiv">FT_MulDiv<a class="headerlink" href="#ft_muldiv" title="Permanent link">&para;</a></h2>
  773. <p>Defined in FT_FREETYPE_H (freetype/freetype.h).</p>
  774. <div class = "codehilite"><pre><code> FT_EXPORT( <a href="ft2-basic_types.html#ft_long">FT_Long</a> )
  775. <b>FT_MulDiv</b>( <a href="ft2-basic_types.html#ft_long">FT_Long</a> a,
  776. <a href="ft2-basic_types.html#ft_long">FT_Long</a> b,
  777. <a href="ft2-basic_types.html#ft_long">FT_Long</a> c );
  778. </code></pre></div>
  779. <p>Compute <code>(a*b)/c</code> with maximum accuracy, using a 64-bit intermediate integer whenever necessary.</p>
  780. <p>This function isn't necessarily as fast as some processor-specific operations, but is at least completely portable.</p>
  781. <h4>input</h4>
  782. <table class="fields">
  783. <tr><td class="val" id="a">a</td><td class="desc">
  784. <p>The first multiplier.</p>
  785. </td></tr>
  786. <tr><td class="val" id="b">b</td><td class="desc">
  787. <p>The second multiplier.</p>
  788. </td></tr>
  789. <tr><td class="val" id="c">c</td><td class="desc">
  790. <p>The divisor.</p>
  791. </td></tr>
  792. </table>
  793. <h4>return</h4>
  794. <p>The result of <code>(a*b)/c</code>. This function never traps when trying to divide by zero; it simply returns &lsquo;MaxInt&rsquo; or &lsquo;MinInt&rsquo; depending on the signs of <code>a</code> and <code>b</code>.</p>
  795. <hr>
  796. <h2 id="ft_mulfix">FT_MulFix<a class="headerlink" href="#ft_mulfix" title="Permanent link">&para;</a></h2>
  797. <p>Defined in FT_FREETYPE_H (freetype/freetype.h).</p>
  798. <div class = "codehilite"><pre><code> FT_EXPORT( <a href="ft2-basic_types.html#ft_long">FT_Long</a> )
  799. <b>FT_MulFix</b>( <a href="ft2-basic_types.html#ft_long">FT_Long</a> a,
  800. <a href="ft2-basic_types.html#ft_long">FT_Long</a> b );
  801. </code></pre></div>
  802. <p>Compute <code>(a*b)/0x10000</code> with maximum accuracy. Its main use is to multiply a given value by a 16.16 fixed-point factor.</p>
  803. <h4>input</h4>
  804. <table class="fields">
  805. <tr><td class="val" id="a">a</td><td class="desc">
  806. <p>The first multiplier.</p>
  807. </td></tr>
  808. <tr><td class="val" id="b">b</td><td class="desc">
  809. <p>The second multiplier. Use a 16.16 factor here whenever possible (see note below).</p>
  810. </td></tr>
  811. </table>
  812. <h4>return</h4>
  813. <p>The result of <code>(a*b)/0x10000</code>.</p>
  814. <h4>note</h4>
  815. <p>This function has been optimized for the case where the absolute value of <code>a</code> is less than 2048, and <code>b</code> is a 16.16 scaling factor. As this happens mainly when scaling from notional units to fractional pixels in FreeType, it resulted in noticeable speed improvements between versions 2.x and 1.x.</p>
  816. <p>As a conclusion, always try to place a 16.16 factor as the <em>second</em> argument of this function; this can make a great difference.</p>
  817. <hr>
  818. <h2 id="ft_divfix">FT_DivFix<a class="headerlink" href="#ft_divfix" title="Permanent link">&para;</a></h2>
  819. <p>Defined in FT_FREETYPE_H (freetype/freetype.h).</p>
  820. <div class = "codehilite"><pre><code> FT_EXPORT( <a href="ft2-basic_types.html#ft_long">FT_Long</a> )
  821. <b>FT_DivFix</b>( <a href="ft2-basic_types.html#ft_long">FT_Long</a> a,
  822. <a href="ft2-basic_types.html#ft_long">FT_Long</a> b );
  823. </code></pre></div>
  824. <p>Compute <code>(a*0x10000)/b</code> with maximum accuracy. Its main use is to divide a given value by a 16.16 fixed-point factor.</p>
  825. <h4>input</h4>
  826. <table class="fields">
  827. <tr><td class="val" id="a">a</td><td class="desc">
  828. <p>The numerator.</p>
  829. </td></tr>
  830. <tr><td class="val" id="b">b</td><td class="desc">
  831. <p>The denominator. Use a 16.16 factor here.</p>
  832. </td></tr>
  833. </table>
  834. <h4>return</h4>
  835. <p>The result of <code>(a*0x10000)/b</code>.</p>
  836. <hr>
  837. <h2 id="ft_roundfix">FT_RoundFix<a class="headerlink" href="#ft_roundfix" title="Permanent link">&para;</a></h2>
  838. <p>Defined in FT_FREETYPE_H (freetype/freetype.h).</p>
  839. <div class = "codehilite"><pre><code> FT_EXPORT( <a href="ft2-basic_types.html#ft_fixed">FT_Fixed</a> )
  840. <b>FT_RoundFix</b>( <a href="ft2-basic_types.html#ft_fixed">FT_Fixed</a> a );
  841. </code></pre></div>
  842. <p>Round a 16.16 fixed number.</p>
  843. <h4>input</h4>
  844. <table class="fields">
  845. <tr><td class="val" id="a">a</td><td class="desc">
  846. <p>The number to be rounded.</p>
  847. </td></tr>
  848. </table>
  849. <h4>return</h4>
  850. <p><code>a</code> rounded to the nearest 16.16 fixed integer, halfway cases away from zero.</p>
  851. <h4>note</h4>
  852. <p>The function uses wrap-around arithmetic.</p>
  853. <hr>
  854. <h2 id="ft_ceilfix">FT_CeilFix<a class="headerlink" href="#ft_ceilfix" title="Permanent link">&para;</a></h2>
  855. <p>Defined in FT_FREETYPE_H (freetype/freetype.h).</p>
  856. <div class = "codehilite"><pre><code> FT_EXPORT( <a href="ft2-basic_types.html#ft_fixed">FT_Fixed</a> )
  857. <b>FT_CeilFix</b>( <a href="ft2-basic_types.html#ft_fixed">FT_Fixed</a> a );
  858. </code></pre></div>
  859. <p>Compute the smallest following integer of a 16.16 fixed number.</p>
  860. <h4>input</h4>
  861. <table class="fields">
  862. <tr><td class="val" id="a">a</td><td class="desc">
  863. <p>The number for which the ceiling function is to be computed.</p>
  864. </td></tr>
  865. </table>
  866. <h4>return</h4>
  867. <p><code>a</code> rounded towards plus infinity.</p>
  868. <h4>note</h4>
  869. <p>The function uses wrap-around arithmetic.</p>
  870. <hr>
  871. <h2 id="ft_floorfix">FT_FloorFix<a class="headerlink" href="#ft_floorfix" title="Permanent link">&para;</a></h2>
  872. <p>Defined in FT_FREETYPE_H (freetype/freetype.h).</p>
  873. <div class = "codehilite"><pre><code> FT_EXPORT( <a href="ft2-basic_types.html#ft_fixed">FT_Fixed</a> )
  874. <b>FT_FloorFix</b>( <a href="ft2-basic_types.html#ft_fixed">FT_Fixed</a> a );
  875. </code></pre></div>
  876. <p>Compute the largest previous integer of a 16.16 fixed number.</p>
  877. <h4>input</h4>
  878. <table class="fields">
  879. <tr><td class="val" id="a">a</td><td class="desc">
  880. <p>The number for which the floor function is to be computed.</p>
  881. </td></tr>
  882. </table>
  883. <h4>return</h4>
  884. <p><code>a</code> rounded towards minus infinity.</p>
  885. <hr>
  886. <h2 id="ft_vector_transform">FT_Vector_Transform<a class="headerlink" href="#ft_vector_transform" title="Permanent link">&para;</a></h2>
  887. <p>Defined in FT_FREETYPE_H (freetype/freetype.h).</p>
  888. <div class = "codehilite"><pre><code> FT_EXPORT( <span class="keyword">void</span> )
  889. <b>FT_Vector_Transform</b>( <a href="ft2-basic_types.html#ft_vector">FT_Vector</a>* vector,
  890. <span class="keyword">const</span> <a href="ft2-basic_types.html#ft_matrix">FT_Matrix</a>* matrix );
  891. </code></pre></div>
  892. <p>Transform a single vector through a 2x2 matrix.</p>
  893. <h4>inout</h4>
  894. <table class="fields">
  895. <tr><td class="val" id="vector">vector</td><td class="desc">
  896. <p>The target vector to transform.</p>
  897. </td></tr>
  898. </table>
  899. <h4>input</h4>
  900. <table class="fields">
  901. <tr><td class="val" id="matrix">matrix</td><td class="desc">
  902. <p>A pointer to the source 2x2 matrix.</p>
  903. </td></tr>
  904. </table>
  905. <h4>note</h4>
  906. <p>The result is undefined if either <code>vector</code> or <code>matrix</code> is invalid.</p>
  907. <hr>
  908. <h2 id="ft_matrix_multiply">FT_Matrix_Multiply<a class="headerlink" href="#ft_matrix_multiply" title="Permanent link">&para;</a></h2>
  909. <p>Defined in FT_GLYPH_H (freetype/ftglyph.h).</p>
  910. <div class = "codehilite"><pre><code> FT_EXPORT( <span class="keyword">void</span> )
  911. <b>FT_Matrix_Multiply</b>( <span class="keyword">const</span> <a href="ft2-basic_types.html#ft_matrix">FT_Matrix</a>* a,
  912. <a href="ft2-basic_types.html#ft_matrix">FT_Matrix</a>* b );
  913. </code></pre></div>
  914. <p>Perform the matrix operation <code>b = a*b</code>.</p>
  915. <h4>input</h4>
  916. <table class="fields">
  917. <tr><td class="val" id="a">a</td><td class="desc">
  918. <p>A pointer to matrix <code>a</code>.</p>
  919. </td></tr>
  920. </table>
  921. <h4>inout</h4>
  922. <table class="fields">
  923. <tr><td class="val" id="b">b</td><td class="desc">
  924. <p>A pointer to matrix <code>b</code>.</p>
  925. </td></tr>
  926. </table>
  927. <h4>note</h4>
  928. <p>The result is undefined if either <code>a</code> or <code>b</code> is zero.</p>
  929. <p>Since the function uses wrap-around arithmetic, results become meaningless if the arguments are very large.</p>
  930. <hr>
  931. <h2 id="ft_matrix_invert">FT_Matrix_Invert<a class="headerlink" href="#ft_matrix_invert" title="Permanent link">&para;</a></h2>
  932. <p>Defined in FT_GLYPH_H (freetype/ftglyph.h).</p>
  933. <div class = "codehilite"><pre><code> FT_EXPORT( <a href="ft2-basic_types.html#ft_error">FT_Error</a> )
  934. <b>FT_Matrix_Invert</b>( <a href="ft2-basic_types.html#ft_matrix">FT_Matrix</a>* matrix );
  935. </code></pre></div>
  936. <p>Invert a 2x2 matrix. Return an error if it can't be inverted.</p>
  937. <h4>inout</h4>
  938. <table class="fields">
  939. <tr><td class="val" id="matrix">matrix</td><td class="desc">
  940. <p>A pointer to the target matrix. Remains untouched in case of error.</p>
  941. </td></tr>
  942. </table>
  943. <h4>return</h4>
  944. <p>FreeType error code. 0&nbsp;means success.</p>
  945. <hr>
  946. <h2 id="ft_angle">FT_Angle<a class="headerlink" href="#ft_angle" title="Permanent link">&para;</a></h2>
  947. <p>Defined in FT_TRIGONOMETRY_H (freetype/fttrigon.h).</p>
  948. <div class = "codehilite"><pre><code> <span class="keyword">typedef</span> <a href="ft2-basic_types.html#ft_fixed">FT_Fixed</a> <b>FT_Angle</b>;
  949. </code></pre></div>
  950. <p>This type is used to model angle values in FreeType. Note that the angle is a 16.16 fixed-point value expressed in degrees.</p>
  951. <hr>
  952. <h2 id="ft_angle_pi">FT_ANGLE_PI<a class="headerlink" href="#ft_angle_pi" title="Permanent link">&para;</a></h2>
  953. <p>Defined in FT_TRIGONOMETRY_H (freetype/fttrigon.h).</p>
  954. <div class = "codehilite"><pre><code>#<span class="keyword">define</span> <b>FT_ANGLE_PI</b> ( 180L &lt;&lt; 16 )
  955. </code></pre></div>
  956. <p>The angle pi expressed in <code><a href="ft2-computations.html#ft_angle">FT_Angle</a></code> units.</p>
  957. <hr>
  958. <h2 id="ft_angle_2pi">FT_ANGLE_2PI<a class="headerlink" href="#ft_angle_2pi" title="Permanent link">&para;</a></h2>
  959. <p>Defined in FT_TRIGONOMETRY_H (freetype/fttrigon.h).</p>
  960. <div class = "codehilite"><pre><code>#<span class="keyword">define</span> <b>FT_ANGLE_2PI</b> ( <a href="ft2-computations.html#ft_angle_pi">FT_ANGLE_PI</a> * 2 )
  961. </code></pre></div>
  962. <p>The angle 2*pi expressed in <code><a href="ft2-computations.html#ft_angle">FT_Angle</a></code> units.</p>
  963. <hr>
  964. <h2 id="ft_angle_pi2">FT_ANGLE_PI2<a class="headerlink" href="#ft_angle_pi2" title="Permanent link">&para;</a></h2>
  965. <p>Defined in FT_TRIGONOMETRY_H (freetype/fttrigon.h).</p>
  966. <div class = "codehilite"><pre><code>#<span class="keyword">define</span> <b>FT_ANGLE_PI2</b> ( <a href="ft2-computations.html#ft_angle_pi">FT_ANGLE_PI</a> / 2 )
  967. </code></pre></div>
  968. <p>The angle pi/2 expressed in <code><a href="ft2-computations.html#ft_angle">FT_Angle</a></code> units.</p>
  969. <hr>
  970. <h2 id="ft_angle_pi4">FT_ANGLE_PI4<a class="headerlink" href="#ft_angle_pi4" title="Permanent link">&para;</a></h2>
  971. <p>Defined in FT_TRIGONOMETRY_H (freetype/fttrigon.h).</p>
  972. <div class = "codehilite"><pre><code>#<span class="keyword">define</span> <b>FT_ANGLE_PI4</b> ( <a href="ft2-computations.html#ft_angle_pi">FT_ANGLE_PI</a> / 4 )
  973. </code></pre></div>
  974. <p>The angle pi/4 expressed in <code><a href="ft2-computations.html#ft_angle">FT_Angle</a></code> units.</p>
  975. <hr>
  976. <h2 id="ft_sin">FT_Sin<a class="headerlink" href="#ft_sin" title="Permanent link">&para;</a></h2>
  977. <p>Defined in FT_TRIGONOMETRY_H (freetype/fttrigon.h).</p>
  978. <div class = "codehilite"><pre><code> FT_EXPORT( <a href="ft2-basic_types.html#ft_fixed">FT_Fixed</a> )
  979. <b>FT_Sin</b>( <a href="ft2-computations.html#ft_angle">FT_Angle</a> angle );
  980. </code></pre></div>
  981. <p>Return the sinus of a given angle in fixed-point format.</p>
  982. <h4>input</h4>
  983. <table class="fields">
  984. <tr><td class="val" id="angle">angle</td><td class="desc">
  985. <p>The input angle.</p>
  986. </td></tr>
  987. </table>
  988. <h4>return</h4>
  989. <p>The sinus value.</p>
  990. <h4>note</h4>
  991. <p>If you need both the sinus and cosinus for a given angle, use the function <code><a href="ft2-computations.html#ft_vector_unit">FT_Vector_Unit</a></code>.</p>
  992. <hr>
  993. <h2 id="ft_cos">FT_Cos<a class="headerlink" href="#ft_cos" title="Permanent link">&para;</a></h2>
  994. <p>Defined in FT_TRIGONOMETRY_H (freetype/fttrigon.h).</p>
  995. <div class = "codehilite"><pre><code> FT_EXPORT( <a href="ft2-basic_types.html#ft_fixed">FT_Fixed</a> )
  996. <b>FT_Cos</b>( <a href="ft2-computations.html#ft_angle">FT_Angle</a> angle );
  997. </code></pre></div>
  998. <p>Return the cosinus of a given angle in fixed-point format.</p>
  999. <h4>input</h4>
  1000. <table class="fields">
  1001. <tr><td class="val" id="angle">angle</td><td class="desc">
  1002. <p>The input angle.</p>
  1003. </td></tr>
  1004. </table>
  1005. <h4>return</h4>
  1006. <p>The cosinus value.</p>
  1007. <h4>note</h4>
  1008. <p>If you need both the sinus and cosinus for a given angle, use the function <code><a href="ft2-computations.html#ft_vector_unit">FT_Vector_Unit</a></code>.</p>
  1009. <hr>
  1010. <h2 id="ft_tan">FT_Tan<a class="headerlink" href="#ft_tan" title="Permanent link">&para;</a></h2>
  1011. <p>Defined in FT_TRIGONOMETRY_H (freetype/fttrigon.h).</p>
  1012. <div class = "codehilite"><pre><code> FT_EXPORT( <a href="ft2-basic_types.html#ft_fixed">FT_Fixed</a> )
  1013. <b>FT_Tan</b>( <a href="ft2-computations.html#ft_angle">FT_Angle</a> angle );
  1014. </code></pre></div>
  1015. <p>Return the tangent of a given angle in fixed-point format.</p>
  1016. <h4>input</h4>
  1017. <table class="fields">
  1018. <tr><td class="val" id="angle">angle</td><td class="desc">
  1019. <p>The input angle.</p>
  1020. </td></tr>
  1021. </table>
  1022. <h4>return</h4>
  1023. <p>The tangent value.</p>
  1024. <hr>
  1025. <h2 id="ft_atan2">FT_Atan2<a class="headerlink" href="#ft_atan2" title="Permanent link">&para;</a></h2>
  1026. <p>Defined in FT_TRIGONOMETRY_H (freetype/fttrigon.h).</p>
  1027. <div class = "codehilite"><pre><code> FT_EXPORT( <a href="ft2-computations.html#ft_angle">FT_Angle</a> )
  1028. <b>FT_Atan2</b>( <a href="ft2-basic_types.html#ft_fixed">FT_Fixed</a> x,
  1029. <a href="ft2-basic_types.html#ft_fixed">FT_Fixed</a> y );
  1030. </code></pre></div>
  1031. <p>Return the arc-tangent corresponding to a given vector (x,y) in the 2d plane.</p>
  1032. <h4>input</h4>
  1033. <table class="fields">
  1034. <tr><td class="val" id="x">x</td><td class="desc">
  1035. <p>The horizontal vector coordinate.</p>
  1036. </td></tr>
  1037. <tr><td class="val" id="y">y</td><td class="desc">
  1038. <p>The vertical vector coordinate.</p>
  1039. </td></tr>
  1040. </table>
  1041. <h4>return</h4>
  1042. <p>The arc-tangent value (i.e. angle).</p>
  1043. <hr>
  1044. <h2 id="ft_angle_diff">FT_Angle_Diff<a class="headerlink" href="#ft_angle_diff" title="Permanent link">&para;</a></h2>
  1045. <p>Defined in FT_TRIGONOMETRY_H (freetype/fttrigon.h).</p>
  1046. <div class = "codehilite"><pre><code> FT_EXPORT( <a href="ft2-computations.html#ft_angle">FT_Angle</a> )
  1047. <b>FT_Angle_Diff</b>( <a href="ft2-computations.html#ft_angle">FT_Angle</a> angle1,
  1048. <a href="ft2-computations.html#ft_angle">FT_Angle</a> angle2 );
  1049. </code></pre></div>
  1050. <p>Return the difference between two angles. The result is always constrained to the ]-PI..PI] interval.</p>
  1051. <h4>input</h4>
  1052. <table class="fields">
  1053. <tr><td class="val" id="angle1">angle1</td><td class="desc">
  1054. <p>First angle.</p>
  1055. </td></tr>
  1056. <tr><td class="val" id="angle2">angle2</td><td class="desc">
  1057. <p>Second angle.</p>
  1058. </td></tr>
  1059. </table>
  1060. <h4>return</h4>
  1061. <p>Constrained value of <code>angle2-angle1</code>.</p>
  1062. <hr>
  1063. <h2 id="ft_vector_unit">FT_Vector_Unit<a class="headerlink" href="#ft_vector_unit" title="Permanent link">&para;</a></h2>
  1064. <p>Defined in FT_TRIGONOMETRY_H (freetype/fttrigon.h).</p>
  1065. <div class = "codehilite"><pre><code> FT_EXPORT( <span class="keyword">void</span> )
  1066. <b>FT_Vector_Unit</b>( <a href="ft2-basic_types.html#ft_vector">FT_Vector</a>* vec,
  1067. <a href="ft2-computations.html#ft_angle">FT_Angle</a> angle );
  1068. </code></pre></div>
  1069. <p>Return the unit vector corresponding to a given angle. After the call, the value of <code>vec.x</code> will be <code>cos(angle)</code>, and the value of <code>vec.y</code> will be <code>sin(angle)</code>.</p>
  1070. <p>This function is useful to retrieve both the sinus and cosinus of a given angle quickly.</p>
  1071. <h4>output</h4>
  1072. <table class="fields">
  1073. <tr><td class="val" id="vec">vec</td><td class="desc">
  1074. <p>The address of target vector.</p>
  1075. </td></tr>
  1076. </table>
  1077. <h4>input</h4>
  1078. <table class="fields">
  1079. <tr><td class="val" id="angle">angle</td><td class="desc">
  1080. <p>The input angle.</p>
  1081. </td></tr>
  1082. </table>
  1083. <hr>
  1084. <h2 id="ft_vector_rotate">FT_Vector_Rotate<a class="headerlink" href="#ft_vector_rotate" title="Permanent link">&para;</a></h2>
  1085. <p>Defined in FT_TRIGONOMETRY_H (freetype/fttrigon.h).</p>
  1086. <div class = "codehilite"><pre><code> FT_EXPORT( <span class="keyword">void</span> )
  1087. <b>FT_Vector_Rotate</b>( <a href="ft2-basic_types.html#ft_vector">FT_Vector</a>* vec,
  1088. <a href="ft2-computations.html#ft_angle">FT_Angle</a> angle );
  1089. </code></pre></div>
  1090. <p>Rotate a vector by a given angle.</p>
  1091. <h4>inout</h4>
  1092. <table class="fields">
  1093. <tr><td class="val" id="vec">vec</td><td class="desc">
  1094. <p>The address of target vector.</p>
  1095. </td></tr>
  1096. </table>
  1097. <h4>input</h4>
  1098. <table class="fields">
  1099. <tr><td class="val" id="angle">angle</td><td class="desc">
  1100. <p>The input angle.</p>
  1101. </td></tr>
  1102. </table>
  1103. <hr>
  1104. <h2 id="ft_vector_length">FT_Vector_Length<a class="headerlink" href="#ft_vector_length" title="Permanent link">&para;</a></h2>
  1105. <p>Defined in FT_TRIGONOMETRY_H (freetype/fttrigon.h).</p>
  1106. <div class = "codehilite"><pre><code> FT_EXPORT( <a href="ft2-basic_types.html#ft_fixed">FT_Fixed</a> )
  1107. <b>FT_Vector_Length</b>( <a href="ft2-basic_types.html#ft_vector">FT_Vector</a>* vec );
  1108. </code></pre></div>
  1109. <p>Return the length of a given vector.</p>
  1110. <h4>input</h4>
  1111. <table class="fields">
  1112. <tr><td class="val" id="vec">vec</td><td class="desc">
  1113. <p>The address of target vector.</p>
  1114. </td></tr>
  1115. </table>
  1116. <h4>return</h4>
  1117. <p>The vector length, expressed in the same units that the original vector coordinates.</p>
  1118. <hr>
  1119. <h2 id="ft_vector_polarize">FT_Vector_Polarize<a class="headerlink" href="#ft_vector_polarize" title="Permanent link">&para;</a></h2>
  1120. <p>Defined in FT_TRIGONOMETRY_H (freetype/fttrigon.h).</p>
  1121. <div class = "codehilite"><pre><code> FT_EXPORT( <span class="keyword">void</span> )
  1122. <b>FT_Vector_Polarize</b>( <a href="ft2-basic_types.html#ft_vector">FT_Vector</a>* vec,
  1123. <a href="ft2-basic_types.html#ft_fixed">FT_Fixed</a> *length,
  1124. <a href="ft2-computations.html#ft_angle">FT_Angle</a> *angle );
  1125. </code></pre></div>
  1126. <p>Compute both the length and angle of a given vector.</p>
  1127. <h4>input</h4>
  1128. <table class="fields">
  1129. <tr><td class="val" id="vec">vec</td><td class="desc">
  1130. <p>The address of source vector.</p>
  1131. </td></tr>
  1132. </table>
  1133. <h4>output</h4>
  1134. <table class="fields">
  1135. <tr><td class="val" id="length">length</td><td class="desc">
  1136. <p>The vector length.</p>
  1137. </td></tr>
  1138. <tr><td class="val" id="angle">angle</td><td class="desc">
  1139. <p>The vector angle.</p>
  1140. </td></tr>
  1141. </table>
  1142. <hr>
  1143. <h2 id="ft_vector_from_polar">FT_Vector_From_Polar<a class="headerlink" href="#ft_vector_from_polar" title="Permanent link">&para;</a></h2>
  1144. <p>Defined in FT_TRIGONOMETRY_H (freetype/fttrigon.h).</p>
  1145. <div class = "codehilite"><pre><code> FT_EXPORT( <span class="keyword">void</span> )
  1146. <b>FT_Vector_From_Polar</b>( <a href="ft2-basic_types.html#ft_vector">FT_Vector</a>* vec,
  1147. <a href="ft2-basic_types.html#ft_fixed">FT_Fixed</a> length,
  1148. <a href="ft2-computations.html#ft_angle">FT_Angle</a> angle );
  1149. </code></pre></div>
  1150. <p>Compute vector coordinates from a length and angle.</p>
  1151. <h4>output</h4>
  1152. <table class="fields">
  1153. <tr><td class="val" id="vec">vec</td><td class="desc">
  1154. <p>The address of source vector.</p>
  1155. </td></tr>
  1156. </table>
  1157. <h4>input</h4>
  1158. <table class="fields">
  1159. <tr><td class="val" id="length">length</td><td class="desc">
  1160. <p>The vector length.</p>
  1161. </td></tr>
  1162. <tr><td class="val" id="angle">angle</td><td class="desc">
  1163. <p>The vector angle.</p>
  1164. </td></tr>
  1165. </table>
  1166. <hr>
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