/* ______ ___ ___ * /\ _ \ /\_ \ /\_ \ * \ \ \L\ \\//\ \ \//\ \ __ __ _ __ ___ * \ \ __ \ \ \ \ \ \ \ /'__`\ /'_ `\/\`'__\/ __`\ * \ \ \/\ \ \_\ \_ \_\ \_/\ __//\ \L\ \ \ \//\ \L\ \ * \ \_\ \_\/\____\/\____\ \____\ \____ \ \_\\ \____/ * \/_/\/_/\/____/\/____/\/____/\/___L\ \/_/ \/___/ * /\____/ * \_/__/ * By Shawn Hargreaves * shawn@talula.demon.co.uk * http://www.talula.demon.co.uk/allegro/ * * Fixed point math routines and lookup tables. * * See readme.txt for copyright information. */ #include #include #include "allegro.h" fixed _cos_tbl[512] = { /* precalculated fixed point (16.16) cosines for a full circle (0-255) */ 65536L, 65531L, 65516L, 65492L, 65457L, 65413L, 65358L, 65294L, 65220L, 65137L, 65043L, 64940L, 64827L, 64704L, 64571L, 64429L, 64277L, 64115L, 63944L, 63763L, 63572L, 63372L, 63162L, 62943L, 62714L, 62476L, 62228L, 61971L, 61705L, 61429L, 61145L, 60851L, 60547L, 60235L, 59914L, 59583L, 59244L, 58896L, 58538L, 58172L, 57798L, 57414L, 57022L, 56621L, 56212L, 55794L, 55368L, 54934L, 54491L, 54040L, 53581L, 53114L, 52639L, 52156L, 51665L, 51166L, 50660L, 50146L, 49624L, 49095L, 48559L, 48015L, 47464L, 46906L, 46341L, 45769L, 45190L, 44604L, 44011L, 43412L, 42806L, 42194L, 41576L, 40951L, 40320L, 39683L, 39040L, 38391L, 37736L, 37076L, 36410L, 35738L, 35062L, 34380L, 33692L, 33000L, 32303L, 31600L, 30893L, 30182L, 29466L, 28745L, 28020L, 27291L, 26558L, 25821L, 25080L, 24335L, 23586L, 22834L, 22078L, 21320L, 20557L, 19792L, 19024L, 18253L, 17479L, 16703L, 15924L, 15143L, 14359L, 13573L, 12785L, 11996L, 11204L, 10411L, 9616L, 8820L, 8022L, 7224L, 6424L, 5623L, 4821L, 4019L, 3216L, 2412L, 1608L, 804L, 0L, -803L, -1607L, -2411L, -3215L, -4018L, -4820L, -5622L, -6423L, -7223L, -8021L, -8819L, -9615L, -10410L, -11203L, -11995L, -12784L, -13572L, -14358L, -15142L, -15923L, -16702L, -17478L, -18252L, -19023L, -19791L, -20556L, -21319L, -22077L, -22833L, -23585L, -24334L, -25079L, -25820L, -26557L, -27290L, -28019L, -28744L, -29465L, -30181L, -30892L, -31599L, -32302L, -32999L, -33691L, -34379L, -35061L, -35737L, -36409L, -37075L, -37735L, -38390L, -39039L, -39682L, -40319L, -40950L, -41575L, -42193L, -42805L, -43411L, -44010L, -44603L, -45189L, -45768L, -46340L, -46905L, -47463L, -48014L, -48558L, -49094L, -49623L, -50145L, -50659L, -51165L, -51664L, -52155L, -52638L, -53113L, -53580L, -54039L, -54490L, -54933L, -55367L, -55793L, -56211L, -56620L, -57021L, -57413L, -57797L, -58171L, -58537L, -58895L, -59243L, -59582L, -59913L, -60234L, -60546L, -60850L, -61144L, -61428L, -61704L, -61970L, -62227L, -62475L, -62713L, -62942L, -63161L, -63371L, -63571L, -63762L, -63943L, -64114L, -64276L, -64428L, -64570L, -64703L, -64826L, -64939L, -65042L, -65136L, -65219L, -65293L, -65357L, -65412L, -65456L, -65491L, -65515L, -65530L, -65536L, -65530L, -65515L, -65491L, -65456L, -65412L, -65357L, -65293L, -65219L, -65136L, -65042L, -64939L, -64826L, -64703L, -64570L, -64428L, -64276L, -64114L, -63943L, -63762L, -63571L, -63371L, -63161L, -62942L, -62713L, -62475L, -62227L, -61970L, -61704L, -61428L, -61144L, -60850L, -60546L, -60234L, -59913L, -59582L, -59243L, -58895L, -58537L, -58171L, -57797L, -57413L, -57021L, -56620L, -56211L, -55793L, -55367L, -54933L, -54490L, -54039L, -53580L, -53113L, -52638L, -52155L, -51664L, -51165L, -50659L, -50145L, -49623L, -49094L, -48558L, -48014L, -47463L, -46905L, -46340L, -45768L, -45189L, -44603L, -44010L, -43411L, -42805L, -42193L, -41575L, -40950L, -40319L, -39682L, -39039L, -38390L, -37735L, -37075L, -36409L, -35737L, -35061L, -34379L, -33691L, -32999L, -32302L, -31599L, -30892L, -30181L, -29465L, -28744L, -28019L, -27290L, -26557L, -25820L, -25079L, -24334L, -23585L, -22833L, -22077L, -21319L, -20556L, -19791L, -19023L, -18252L, -17478L, -16702L, -15923L, -15142L, -14358L, -13572L, -12784L, -11995L, -11203L, -10410L, -9615L, -8819L, -8021L, -7223L, -6423L, -5622L, -4820L, -4018L, -3215L, -2411L, -1607L, -803L, 0L, 804L, 1608L, 2412L, 3216L, 4019L, 4821L, 5623L, 6424L, 7224L, 8022L, 8820L, 9616L, 10411L, 11204L, 11996L, 12785L, 13573L, 14359L, 15143L, 15924L, 16703L, 17479L, 18253L, 19024L, 19792L, 20557L, 21320L, 22078L, 22834L, 23586L, 24335L, 25080L, 25821L, 26558L, 27291L, 28020L, 28745L, 29466L, 30182L, 30893L, 31600L, 32303L, 33000L, 33692L, 34380L, 35062L, 35738L, 36410L, 37076L, 37736L, 38391L, 39040L, 39683L, 40320L, 40951L, 41576L, 42194L, 42806L, 43412L, 44011L, 44604L, 45190L, 45769L, 46341L, 46906L, 47464L, 48015L, 48559L, 49095L, 49624L, 50146L, 50660L, 51166L, 51665L, 52156L, 52639L, 53114L, 53581L, 54040L, 54491L, 54934L, 55368L, 55794L, 56212L, 56621L, 57022L, 57414L, 57798L, 58172L, 58538L, 58896L, 59244L, 59583L, 59914L, 60235L, 60547L, 60851L, 61145L, 61429L, 61705L, 61971L, 62228L, 62476L, 62714L, 62943L, 63162L, 63372L, 63572L, 63763L, 63944L, 64115L, 64277L, 64429L, 64571L, 64704L, 64827L, 64940L, 65043L, 65137L, 65220L, 65294L, 65358L, 65413L, 65457L, 65492L, 65516L, 65531L }; fixed _tan_tbl[256] = { /* precalculated fixed point (16.16) tangents for a half circle (0-127) */ 0L, 804L, 1609L, 2414L, 3220L, 4026L, 4834L, 5644L, 6455L, 7268L, 8083L, 8901L, 9721L, 10545L, 11372L, 12202L, 13036L, 13874L, 14717L, 15564L, 16416L, 17273L, 18136L, 19005L, 19880L, 20762L, 21650L, 22546L, 23449L, 24360L, 25280L, 26208L, 27146L, 28093L, 29050L, 30018L, 30996L, 31986L, 32988L, 34002L, 35030L, 36071L, 37126L, 38196L, 39281L, 40382L, 41500L, 42636L, 43790L, 44963L, 46156L, 47369L, 48605L, 49863L, 51145L, 52451L, 53784L, 55144L, 56532L, 57950L, 59398L, 60880L, 62395L, 63947L, 65536L, 67165L, 68835L, 70548L, 72308L, 74116L, 75974L, 77887L, 79856L, 81885L, 83977L, 86135L, 88365L, 90670L, 93054L, 95523L, 98082L, 100736L, 103493L, 106358L, 109340L, 112447L, 115687L, 119071L, 122609L, 126314L, 130198L, 134276L, 138564L, 143081L, 147847L, 152884L, 158218L, 163878L, 169896L, 176309L, 183161L, 190499L, 198380L, 206870L, 216043L, 225990L, 236817L, 248648L, 261634L, 275959L, 291845L, 309568L, 329472L, 351993L, 377693L, 407305L, 441808L, 482534L, 531352L, 590958L, 665398L, 761030L, 888450L, 1066730L, 1334016L, 1779314L, 2669641L, 5340086L, -2147483647L, -5340085L, -2669640L, -1779313L, -1334015L, -1066729L, -888449L, -761029L, -665397L, -590957L, -531351L, -482533L, -441807L, -407304L, -377692L, -351992L, -329471L, -309567L, -291844L, -275958L, -261633L, -248647L, -236816L, -225989L, -216042L, -206869L, -198379L, -190498L, -183160L, -176308L, -169895L, -163877L, -158217L, -152883L, -147846L, -143080L, -138563L, -134275L, -130197L, -126313L, -122608L, -119070L, -115686L, -112446L, -109339L, -106357L, -103492L, -100735L, -98081L, -95522L, -93053L, -90669L, -88364L, -86134L, -83976L, -81884L, -79855L, -77886L, -75973L, -74115L, -72307L, -70547L, -68834L, -67164L, -65535L, -63946L, -62394L, -60879L, -59397L, -57949L, -56531L, -55143L, -53783L, -52450L, -51144L, -49862L, -48604L, -47368L, -46155L, -44962L, -43789L, -42635L, -41499L, -40381L, -39280L, -38195L, -37125L, -36070L, -35029L, -34001L, -32987L, -31985L, -30995L, -30017L, -29049L, -28092L, -27145L, -26207L, -25279L, -24359L, -23448L, -22545L, -21649L, -20761L, -19879L, -19004L, -18135L, -17272L, -16415L, -15563L, -14716L, -13873L, -13035L, -12201L, -11371L, -10544L, -9720L, -8900L, -8082L, -7267L, -6454L, -5643L, -4833L, -4025L, -3219L, -2413L, -1608L, -803L }; fixed _acos_tbl[513] = { /* precalculated fixed point (16.16) inverse cosines (-1 to 1) */ 0x800000L, 0x7C65C7L, 0x7AE75AL, 0x79C19EL, 0x78C9BEL, 0x77EF25L, 0x772953L, 0x76733AL, 0x75C991L, 0x752A10L, 0x74930CL, 0x740345L, 0x7379C1L, 0x72F5BAL, 0x72768FL, 0x71FBBCL, 0x7184D3L, 0x711174L, 0x70A152L, 0x703426L, 0x6FC9B5L, 0x6F61C9L, 0x6EFC36L, 0x6E98D1L, 0x6E3777L, 0x6DD805L, 0x6D7A5EL, 0x6D1E68L, 0x6CC40BL, 0x6C6B2FL, 0x6C13C1L, 0x6BBDAFL, 0x6B68E6L, 0x6B1558L, 0x6AC2F5L, 0x6A71B1L, 0x6A217EL, 0x69D251L, 0x698420L, 0x6936DFL, 0x68EA85L, 0x689F0AL, 0x685465L, 0x680A8DL, 0x67C17DL, 0x67792CL, 0x673194L, 0x66EAAFL, 0x66A476L, 0x665EE5L, 0x6619F5L, 0x65D5A2L, 0x6591E7L, 0x654EBFL, 0x650C26L, 0x64CA18L, 0x648890L, 0x64478CL, 0x640706L, 0x63C6FCL, 0x63876BL, 0x63484FL, 0x6309A5L, 0x62CB6AL, 0x628D9CL, 0x625037L, 0x621339L, 0x61D69FL, 0x619A68L, 0x615E90L, 0x612316L, 0x60E7F7L, 0x60AD31L, 0x6072C3L, 0x6038A9L, 0x5FFEE3L, 0x5FC56EL, 0x5F8C49L, 0x5F5372L, 0x5F1AE7L, 0x5EE2A7L, 0x5EAAB0L, 0x5E7301L, 0x5E3B98L, 0x5E0473L, 0x5DCD92L, 0x5D96F3L, 0x5D6095L, 0x5D2A76L, 0x5CF496L, 0x5CBEF2L, 0x5C898BL, 0x5C545EL, 0x5C1F6BL, 0x5BEAB0L, 0x5BB62DL, 0x5B81E1L, 0x5B4DCAL, 0x5B19E7L, 0x5AE638L, 0x5AB2BCL, 0x5A7F72L, 0x5A4C59L, 0x5A1970L, 0x59E6B6L, 0x59B42AL, 0x5981CCL, 0x594F9BL, 0x591D96L, 0x58EBBDL, 0x58BA0EL, 0x588889L, 0x58572DL, 0x5825FAL, 0x57F4EEL, 0x57C40AL, 0x57934DL, 0x5762B5L, 0x573243L, 0x5701F5L, 0x56D1CCL, 0x56A1C6L, 0x5671E4L, 0x564224L, 0x561285L, 0x55E309L, 0x55B3ADL, 0x558471L, 0x555555L, 0x552659L, 0x54F77BL, 0x54C8BCL, 0x549A1BL, 0x546B98L, 0x543D31L, 0x540EE7L, 0x53E0B9L, 0x53B2A7L, 0x5384B0L, 0x5356D4L, 0x532912L, 0x52FB6BL, 0x52CDDDL, 0x52A068L, 0x52730CL, 0x5245C9L, 0x52189EL, 0x51EB8BL, 0x51BE8FL, 0x5191AAL, 0x5164DCL, 0x513825L, 0x510B83L, 0x50DEF7L, 0x50B280L, 0x50861FL, 0x5059D2L, 0x502D99L, 0x500175L, 0x4FD564L, 0x4FA967L, 0x4F7D7DL, 0x4F51A6L, 0x4F25E2L, 0x4EFA30L, 0x4ECE90L, 0x4EA301L, 0x4E7784L, 0x4E4C19L, 0x4E20BEL, 0x4DF574L, 0x4DCA3AL, 0x4D9F10L, 0x4D73F6L, 0x4D48ECL, 0x4D1DF1L, 0x4CF305L, 0x4CC829L, 0x4C9D5AL, 0x4C729AL, 0x4C47E9L, 0x4C1D45L, 0x4BF2AEL, 0x4BC826L, 0x4B9DAAL, 0x4B733BL, 0x4B48D9L, 0x4B1E84L, 0x4AF43BL, 0x4AC9FEL, 0x4A9FCDL, 0x4A75A7L, 0x4A4B8DL, 0x4A217EL, 0x49F77AL, 0x49CD81L, 0x49A393L, 0x4979AFL, 0x494FD5L, 0x492605L, 0x48FC3FL, 0x48D282L, 0x48A8CFL, 0x487F25L, 0x485584L, 0x482BECL, 0x48025DL, 0x47D8D6L, 0x47AF57L, 0x4785E0L, 0x475C72L, 0x47330AL, 0x4709ABL, 0x46E052L, 0x46B701L, 0x468DB7L, 0x466474L, 0x463B37L, 0x461201L, 0x45E8D0L, 0x45BFA6L, 0x459682L, 0x456D64L, 0x45444BL, 0x451B37L, 0x44F229L, 0x44C920L, 0x44A01CL, 0x44771CL, 0x444E21L, 0x44252AL, 0x43FC38L, 0x43D349L, 0x43AA5FL, 0x438178L, 0x435894L, 0x432FB4L, 0x4306D8L, 0x42DDFEL, 0x42B527L, 0x428C53L, 0x426381L, 0x423AB2L, 0x4211E5L, 0x41E91AL, 0x41C051L, 0x41978AL, 0x416EC5L, 0x414601L, 0x411D3EL, 0x40F47CL, 0x40CBBBL, 0x40A2FBL, 0x407A3CL, 0x40517DL, 0x4028BEL, 0x400000L, 0x3FD742L, 0x3FAE83L, 0x3F85C4L, 0x3F5D05L, 0x3F3445L, 0x3F0B84L, 0x3EE2C2L, 0x3EB9FFL, 0x3E913BL, 0x3E6876L, 0x3E3FAFL, 0x3E16E6L, 0x3DEE1BL, 0x3DC54EL, 0x3D9C7FL, 0x3D73ADL, 0x3D4AD9L, 0x3D2202L, 0x3CF928L, 0x3CD04CL, 0x3CA76CL, 0x3C7E88L, 0x3C55A1L, 0x3C2CB7L, 0x3C03C8L, 0x3BDAD6L, 0x3BB1DFL, 0x3B88E4L, 0x3B5FE4L, 0x3B36E0L, 0x3B0DD7L, 0x3AE4C9L, 0x3ABBB5L, 0x3A929CL, 0x3A697EL, 0x3A405AL, 0x3A1730L, 0x39EDFFL, 0x39C4C9L, 0x399B8CL, 0x397249L, 0x3948FFL, 0x391FAEL, 0x38F655L, 0x38CCF6L, 0x38A38EL, 0x387A20L, 0x3850A9L, 0x38272AL, 0x37FDA3L, 0x37D414L, 0x37AA7CL, 0x3780DBL, 0x375731L, 0x372D7EL, 0x3703C1L, 0x36D9FBL, 0x36B02BL, 0x368651L, 0x365C6DL, 0x36327FL, 0x360886L, 0x35DE82L, 0x35B473L, 0x358A59L, 0x356033L, 0x353602L, 0x350BC5L, 0x34E17CL, 0x34B727L, 0x348CC5L, 0x346256L, 0x3437DAL, 0x340D52L, 0x33E2BBL, 0x33B817L, 0x338D66L, 0x3362A6L, 0x3337D7L, 0x330CFBL, 0x32E20FL, 0x32B714L, 0x328C0AL, 0x3260F0L, 0x3235C6L, 0x320A8CL, 0x31DF42L, 0x31B3E7L, 0x31887CL, 0x315CFFL, 0x313170L, 0x3105D0L, 0x30DA1EL, 0x30AE5AL, 0x308283L, 0x305699L, 0x302A9CL, 0x2FFE8BL, 0x2FD267L, 0x2FA62EL, 0x2F79E1L, 0x2F4D80L, 0x2F2109L, 0x2EF47DL, 0x2EC7DBL, 0x2E9B24L, 0x2E6E56L, 0x2E4171L, 0x2E1475L, 0x2DE762L, 0x2DBA37L, 0x2D8CF4L, 0x2D5F98L, 0x2D3223L, 0x2D0495L, 0x2CD6EEL, 0x2CA92CL, 0x2C7B50L, 0x2C4D59L, 0x2C1F47L, 0x2BF119L, 0x2BC2CFL, 0x2B9468L, 0x2B65E5L, 0x2B3744L, 0x2B0885L, 0x2AD9A7L, 0x2AAAABL, 0x2A7B8FL, 0x2A4C53L, 0x2A1CF7L, 0x29ED7BL, 0x29BDDCL, 0x298E1CL, 0x295E3AL, 0x292E34L, 0x28FE0BL, 0x28CDBDL, 0x289D4BL, 0x286CB3L, 0x283BF6L, 0x280B12L, 0x27DA06L, 0x27A8D3L, 0x277777L, 0x2745F2L, 0x271443L, 0x26E26AL, 0x26B065L, 0x267E34L, 0x264BD6L, 0x26194AL, 0x25E690L, 0x25B3A7L, 0x25808EL, 0x254D44L, 0x2519C8L, 0x24E619L, 0x24B236L, 0x247E1FL, 0x2449D3L, 0x241550L, 0x23E095L, 0x23ABA2L, 0x237675L, 0x23410EL, 0x230B6AL, 0x22D58AL, 0x229F6BL, 0x22690DL, 0x22326EL, 0x21FB8DL, 0x21C468L, 0x218CFFL, 0x215550L, 0x211D59L, 0x20E519L, 0x20AC8EL, 0x2073B7L, 0x203A92L, 0x20011DL, 0x1FC757L, 0x1F8D3DL, 0x1F52CFL, 0x1F1809L, 0x1EDCEAL, 0x1EA170L, 0x1E6598L, 0x1E2961L, 0x1DECC7L, 0x1DAFC9L, 0x1D7264L, 0x1D3496L, 0x1CF65BL, 0x1CB7B1L, 0x1C7895L, 0x1C3904L, 0x1BF8FAL, 0x1BB874L, 0x1B7770L, 0x1B35E8L, 0x1AF3DAL, 0x1AB141L, 0x1A6E19L, 0x1A2A5EL, 0x19E60BL, 0x19A11BL, 0x195B8AL, 0x191551L, 0x18CE6CL, 0x1886D4L, 0x183E83L, 0x17F573L, 0x17AB9BL, 0x1760F6L, 0x17157BL, 0x16C921L, 0x167BE0L, 0x162DAFL, 0x15DE82L, 0x158E4FL, 0x153D0BL, 0x14EAA8L, 0x14971AL, 0x144251L, 0x13EC3FL, 0x1394D1L, 0x133BF5L, 0x12E198L, 0x1285A2L, 0x1227FBL, 0x11C889L, 0x11672FL, 0x1103CAL, 0x109E37L, 0x10364BL, 0xFCBDAL, 0xF5EAEL, 0xEEE8CL, 0xE7B2DL, 0xE0444L, 0xD8971L, 0xD0A46L, 0xC863FL, 0xBFCBBL, 0xB6CF4L, 0xAD5F0L, 0xA366FL, 0x98CC6L, 0x8D6ADL, 0x810DBL, 0x73642L, 0x63E62L, 0x518A6L, 0x39A39L, 0x0L }; #if defined __GNUC__ && defined __i386__ static short sqrt_table[256] = { /* this table is used by the fsqrt() function */ 0x2D4, 0x103F, 0x16CD, 0x1BDB, 0x201F, 0x23E3, 0x274B, 0x2A6D, 0x2D57, 0x3015, 0x32AC, 0x3524, 0x377F, 0x39C2, 0x3BEE, 0x3E08, 0x400F, 0x4207, 0x43F0, 0x45CC, 0x479C, 0x4960, 0x4B19, 0x4CC9, 0x4E6F, 0x500C, 0x51A2, 0x532F, 0x54B6, 0x5635, 0x57AE, 0x5921, 0x5A8D, 0x5BF4, 0x5D56, 0x5EB3, 0x600A, 0x615D, 0x62AB, 0x63F5, 0x653B, 0x667D, 0x67BA, 0x68F5, 0x6A2B, 0x6B5E, 0x6C8D, 0x6DBA, 0x6EE3, 0x7009, 0x712C, 0x724C, 0x7369, 0x7484, 0x759C, 0x76B1, 0x77C4, 0x78D4, 0x79E2, 0x7AEE, 0x7BF7, 0x7CFE, 0x7E04, 0x7F07, 0x8007, 0x8106, 0x8203, 0x82FF, 0x83F8, 0x84EF, 0x85E5, 0x86D9, 0x87CB, 0x88BB, 0x89AA, 0x8A97, 0x8B83, 0x8C6D, 0x8D56, 0x8E3D, 0x8F22, 0x9007, 0x90E9, 0x91CB, 0x92AB, 0x938A, 0x9467, 0x9543, 0x961E, 0x96F8, 0x97D0, 0x98A8, 0x997E, 0x9A53, 0x9B26, 0x9BF9, 0x9CCA, 0x9D9B, 0x9E6A, 0x9F39, 0xA006, 0xA0D2, 0xA19D, 0xA268, 0xA331, 0xA3F9, 0xA4C1, 0xA587, 0xA64D, 0xA711, 0xA7D5, 0xA898, 0xA95A, 0xAA1B, 0xAADB, 0xAB9A, 0xAC59, 0xAD16, 0xADD3, 0xAE8F, 0xAF4B, 0xB005, 0xB0BF, 0xB178, 0xB230, 0xB2E8, 0xB39F, 0xB455, 0xB50A, 0xB5BF, 0xB673, 0xB726, 0xB7D9, 0xB88A, 0xB93C, 0xB9EC, 0xBA9C, 0xBB4B, 0xBBFA, 0xBCA8, 0xBD55, 0xBE02, 0xBEAE, 0xBF5A, 0xC005, 0xC0AF, 0xC159, 0xC202, 0xC2AB, 0xC353, 0xC3FA, 0xC4A1, 0xC548, 0xC5ED, 0xC693, 0xC737, 0xC7DC, 0xC87F, 0xC923, 0xC9C5, 0xCA67, 0xCB09, 0xCBAA, 0xCC4B, 0xCCEB, 0xCD8B, 0xCE2A, 0xCEC8, 0xCF67, 0xD004, 0xD0A2, 0xD13F, 0xD1DB, 0xD277, 0xD312, 0xD3AD, 0xD448, 0xD4E2, 0xD57C, 0xD615, 0xD6AE, 0xD746, 0xD7DE, 0xD876, 0xD90D, 0xD9A4, 0xDA3A, 0xDAD0, 0xDB66, 0xDBFB, 0xDC90, 0xDD24, 0xDDB8, 0xDE4C, 0xDEDF, 0xDF72, 0xE004, 0xE096, 0xE128, 0xE1B9, 0xE24A, 0xE2DB, 0xE36B, 0xE3FB, 0xE48B, 0xE51A, 0xE5A9, 0xE637, 0xE6C5, 0xE753, 0xE7E1, 0xE86E, 0xE8FB, 0xE987, 0xEA13, 0xEA9F, 0xEB2B, 0xEBB6, 0xEC41, 0xECCB, 0xED55, 0xEDDF, 0xEE69, 0xEEF2, 0xEF7B, 0xF004, 0xF08C, 0xF114, 0xF19C, 0xF223, 0xF2AB, 0xF332, 0xF3B8, 0xF43E, 0xF4C4, 0xF54A, 0xF5D0, 0xF655, 0xF6DA, 0xF75E, 0xF7E3, 0xF867, 0xF8EA, 0xF96E, 0xF9F1, 0xFA74, 0xFAF7, 0xFB79, 0xFBFB, 0xFC7D, 0xFCFF, 0xFD80, 0xFE02, 0xFE82, 0xFF03, 0xFF83 }; #endif /* fatan: * Fixed point inverse tangent. Does a binary search on the tan table. */ fixed fatan(fixed x) { int a, b, c; /* for binary search */ fixed d; /* difference value for search */ if (x >= 0) { /* search the first part of tan table */ a = 0; b = 127; } else { /* search the second half instead */ a = 128; b = 255; } do { c = (a + b) >> 1; d = x - _tan_tbl[c]; if (d > 0) a = c + 1; else if (d < 0) b = c - 1; } while ((a <= b) && (d)); if (x >= 0) return ((long)c) << 15; return (-0x00800000L + (((long)c) << 15)); } /* fatan2: * Like the libc atan2, but for fixed point numbers. */ fixed fatan2(fixed y, fixed x) { fixed r; if (x==0) { if (y==0) { errno = EDOM; return 0L; } else return ((y < 0) ? -0x00400000L : 0x00400000L); } errno = 0; r = fdiv(y,x); if (errno) { errno = 0; return ((y < 0) ? -0x00400000L : 0x00400000L); } r = fatan(r); if (x >= 0) return r; if (y >= 0) return 0x00800000L + r; return r - 0x00800000L; } /* fsqrt: * Fixed point square root routine. This code is taken from the fixfloat * library by Arne Steinarson. */ fixed fsqrt(fixed x) { #if defined __GNUC__ && defined __i386__ fixed ecx __attribute__ ((__unused__)); fixed edx __attribute__ ((__unused__)); fixed result; if (x <= 0) { if (x < 0) errno = EDOM; return 0; } /* for gcc on i386 */ asm ( " movl %3, %0 ; " " fsqrt_not_zero: " " xorl %%ecx, %%ecx ; " " cmpl $0x010000, %0 ; " /* series of shifts to reduce range */ " jb fsqrt_0 ; " " shrl $16, %0 ; " " addb $16, %%cl ; " " fsqrt_0: " " cmpl $0x0100, %0 ; " " jb fsqrt_1 ; " " shrl $8, %0 ; " " addb $8, %%cl ; " " fsqrt_1: " " cmpl $0x010, %0 ; " " jb fsqrt_2 ; " " shrl $4, %0 ; " " addb $4, %%cl ; " " fsqrt_2: " " cmpl $0x04, %0 ; " " jb fsqrt_3 ; " " shrl $2, %0 ; " " addb $2, %%cl ; " " fsqrt_3: " " cmpl $2, %0 ; " " jb fsqrt_4 ; " " incl %%ecx ; " " fsqrt_4: " " movl %3, %0 ; " " subb $15, %%cl ; " " testb $1, %%cl ; " " je fsqrt_cl_even ; " " incb %%cl ; " " fsqrt_cl_even: " " movb %%cl, %%dl ; " " addb $4, %%cl ; " " jns fsqrt_cl_pve ; " " negb %%cl ; " " shll %%cl, %0 ; " " jmp fsqrt_cl_nve_done ; " " fsqrt_cl_pve: " " shrl %%cl, %0 ; " " fsqrt_cl_nve_done: " " sarb $1, %%dl ; " /* table lookup */ " shrl $4, %0 ; " " movw (%4, %0, 2), %w0 ; " " movb %%dl, %%cl ; " " testb %%cl, %%cl ; " " js fsqrt_cl_nve ; " " shll %%cl, %0 ; " /* shift back into proper range */ " jmp fsqrt_done ; " " fsqrt_cl_nve: " " negb %%cl ; " " shrl %%cl, %0 ; " " fsqrt_done: " : "=&a" (result), /* result in eax */ "=&c" (ecx), /* reliably reserve ecx */ "=&d" (edx) /* reliably reserve edx */ : "rm" (x), /* parameter in reg or memory */ "r" (sqrt_table) /* precalculated table in reg */ ); return result; #else /* for other compilers/platforms */ fixed result; if (x <= 0) { if (x < 0) errno = EDOM; return 0; } return result = ftofix (sqrt (fixtof (x))); #endif }