shithub: pt2-clone

--- a/src/pt2_blep.c

+++ b/src/pt2_blep.c

@@ -4,85 +4,81 @@

 #include <assert.h>

 #include "pt2_blep.h"

-/* Why this table is not represented as readable floating-point numbers:

-** Accurate double representation in string format requires at least 14 digits and normalized

-** (scientific) notation, notwithstanding compiler issues with precision or rounding error.

-** Also, don't touch this table ever, just keep it exactly identical!

+/* 18th of April 2022, 8bitbubsy:

+** Table entries were changed to readable numbers instead of "IEEE 754" 64-bit hex data, for better cross-platform support.

+** These numbers have enough digits to keep the same accuracy as the old table (verified).

+** If some compilers were to make a small rounding error here, it wouldn't matter. We have good enough accuracy anyway.

*/

-static const uint64_t minblepdata[] =

+static const double dMinblepData[256 + 1] =

-	0x3FF000320C7E95A6,0x3FF00049BE220FD5,0x3FF0001B92A41ACA,0x3FEFFF4425AA9724,

-	0x3FEFFDABDF6CF05C,0x3FEFFB5AF233EF1A,0x3FEFF837E2AE85F3,0x3FEFF4217B80E938,

-	0x3FEFEEECEB4E0444,0x3FEFE863A8358B5F,0x3FEFE04126292670,0x3FEFD63072A0D592,

-	0x3FEFC9C9CD36F56F,0x3FEFBA90594BD8C3,0x3FEFA7F008BA9F13,0x3FEF913BE2A0E0E2,

-	0x3FEF75ACCB01A327,0x3FEF5460F06A4E8F,0x3FEF2C5C0389BD3C,0x3FEEFC8859BF6BCB,

-	0x3FEEC3B916FD8D19,0x3FEE80AD74F0AD16,0x3FEE32153552E2C7,0x3FEDD69643CB9778,

-	0x3FED6CD380FFA864,0x3FECF374A4D2961A,0x3FEC692F19B34E54,0x3FEBCCCFA695DD5C,

-	0x3FEB1D44B168764A,0x3FEA59A8D8E4527F,0x3FE9814D9B10A9A3,0x3FE893C5B62135F2,

-	0x3FE790EEEBF9DABD,0x3FE678FACDEE27FF,0x3FE54C763699791A,0x3FE40C4F1B1EB7A3,

-	0x3FE2B9D863D4E0F3,0x3FE156CB86586B0B,0x3FDFCA8F5005B828,0x3FDCCF9C3F455DAC,

-	0x3FD9C2787F20D06E,0x3FD6A984CAD0F3E5,0x3FD38BB0C452732E,0x3FD0705EC7135366,

-	0x3FCABE86754E238F,0x3FC4C0801A6E9A04,0x3FBDECF490C5EA17,0x3FB2DFFACE9CE44B,

-	0x3FA0EFD4449F4620,0xBF72F4A65E22806D,0xBFA3F872D761F927,0xBFB1D89F0FD31F7C,

-	0xBFB8B1EA652EC270,0xBFBE79B82A37C92D,0xBFC1931B697E685E,0xBFC359383D4C8ADA,

-	0xBFC48F3BFF81B06B,0xBFC537BBA8D6B15C,0xBFC557CEF2168326,0xBFC4F6F781B3347A,

-	0xBFC41EF872F0E009,0xBFC2DB9F119D54D3,0xBFC13A7E196CB44F,0xBFBE953A67843504,

-	0xBFBA383D9C597E74,0xBFB57FBD67AD55D6,0xBFB08E18234E5CB3,0xBFA70B06D699FFD1,

-	0xBF9A1CFB65370184,0xBF7B2CEB901D2067,0x3F86D5DE2C267C78,0x3F9C1D9EF73F384D,

-	0x3FA579C530950503,0x3FABD1E5FFF9B1D0,0x3FB07DCDC3A4FB5B,0x3FB2724A856EEC1B,

-	0x3FB3C1F7199FC822,0x3FB46D0979F5043B,0x3FB47831387E0110,0x3FB3EC4A58A3D527,

-	0x3FB2D5F45F8889B3,0x3FB145113E25B749,0x3FAE9860D18779BC,0x3FA9FFD5F5AB96EA,

-	0x3FA4EC6C4F47777E,0x3F9F16C5B2604C3A,0x3F9413D801124DB7,0x3F824F668CBB5BDF,

-	0xBF55B3FA2EE30D66,0xBF86541863B38183,0xBF94031BBBD551DE,0xBF9BAFC27DC5E769,

-	0xBFA102B3683C57EC,0xBFA3731E608CC6E4,0xBFA520C9F5B5DEBD,0xBFA609DC89BE6ECE,

-	0xBFA632B83BC5F52F,0xBFA5A58885841AD4,0xBFA471A5D2FF02F3,0xBFA2AAD5CD0377C7,

-	0xBFA0686FFE4B9B05,0xBF9B88DE413ACB69,0xBF95B4EF6D93F1C5,0xBF8F1B72860B27FA,

-	0xBF8296A865CDF612,0xBF691BEEDABE928B,0x3F65C04E6AF9D4F1,0x3F8035D8FFCDB0F8,

-	0x3F89BED23C431BE3,0x3F90E737811A1D21,0x3F941C2040BD7CB1,0x3F967046EC629A09,

-	0x3F97DE27ECE9ED89,0x3F98684DE31E7040,0x3F9818C4B07718FA,0x3F97005261F91F60,

-	0x3F95357FDD157646,0x3F92D37C696C572A,0x3F8FF1CFF2BEECB5,0x3F898D20C7A72AC4,

-	0x3F82BC5B3B0AE2DF,0x3F7784A1B8E9E667,0x3F637BB14081726B,0xBF4B2DACA70C60A9,

-	0xBF6EFB00AD083727,0xBF7A313758DC6AE9,0xBF819D6A99164BE0,0xBF8533F57533403B,

-	0xBF87CD120DB5D340,0xBF89638549CD25DE,0xBF89FB8B8D37B1BB,0xBF89A21163F9204E,

-	0xBF886BA8931297D4,0xBF8673477783D71E,0xBF83D8E1CB165DB8,0xBF80BFEA7216142A,

-	0xBF7A9B9BC2E40EBF,0xBF7350E806435A7E,0xBF67D35D3734AB5E,0xBF52ADE8FEAB8DB9,

-	0x3F415669446478E4,0x3F60C56A092AFB48,0x3F6B9F4334A4561F,0x3F724FB908FD87AA,

-	0x3F75CC56DFE382EA,0x3F783A0C23969A7B,0x3F799833C40C3B82,0x3F79F02721981BF3,

-	0x3F7954212AB35261,0x3F77DDE0C5FC15C9,0x3F75AD1C98FE0777,0x3F72E5DACC0849F2,

-	0x3F6F5D7E69DFDE1B,0x3F685EC2CA09E1FD,0x3F611D750E54DF3A,0x3F53C6E392A46D17,

-	0x3F37A046885F3365,0xBF3BB034D2EE45C2,0xBF5254267B04B482,0xBF5C0516F9CECDC6,

-	0xBF61E5736853564D,0xBF64C464B9CC47AB,0xBF669C1AEF258F56,0xBF67739985DD0E60,

-	0xBF675AFD6446395B,0xBF666A0C909B4F78,0xBF64BE9879A7A07B,0xBF627AC74B119DBD,

-	0xBF5F86B04069DC9B,0xBF597BE8F754AF5E,0xBF531F3EAAE9A1B1,0xBF496D3DE6AD7EA3,

-	0xBF3A05FFDE4670CF,0xBF06DF95C93A85CA,0x3F31EE2B2C6547AC,0x3F41E694A378C129,

-	0x3F4930BF840E23C9,0x3F4EBB5D05A0D47D,0x3F51404DA0539855,0x3F524698F56B3F33,

-	0x3F527EF85309E28F,0x3F51FE70FE2513DE,0x3F50DF1642009B74,0x3F4E7CDA93517CAE,

-	0x3F4A77AE24F9A533,0x3F45EE226AA69E10,0x3F411DB747374F52,0x3F387F39D229D97F,

-	0x3F2E1B3D39AF5F8B,0x3F18F557BB082715,0xBEFAC04896E68DDB,0xBF20F5BC77DF558A,

-	0xBF2C1B6DF3EE94A4,0xBF3254602A816876,0xBF354E90F6EAC26B,0xBF3709F2E5AF1624,

-	0xBF379FCCB331CE8E,0xBF37327192ADDAD3,0xBF35EA998A894237,0xBF33F4C4977B3489,

-	0xBF317EC5F68E887B,0xBF2D6B1F793EB773,0xBF2786A226B076D9,0xBF219BE6CEC2CA36,

-	0xBF17D7F36D2A3A18,0xBF0AAEC5BBAB42AB,0xBEF01818DC224040,0x3EEF2F6E21093846,

-	0x3F049D6E0060B71F,0x3F0E598CCAFABEFD,0x3F128BC14BE97261,0x3F148703BC70EF6A,

-	0x3F1545E1579CAA25,0x3F14F7DDF5F8D766,0x3F13D10FF9A1BE0C,0x3F1206D5738ECE3A,

-	0x3F0F99F6BF17C5D4,0x3F0AA6D7EA524E96,0x3F0588DDF740E1F4,0x3F0086FB6FEA9839,

-	0x3EF7B28F6D6F5EED,0x3EEEA300DCBAF74A,0x3EE03F904789777C,0x3EC1BFEB320501ED,

-	0xBEC310D8E585A031,0xBED6F55ECA7E151F,0xBEDFDAA5DACDD0B7,0xBEE26944F3CF6E90,

-	0xBEE346894453BD1F,0xBEE2E099305CD5A8,0xBEE190385A7EA8B2,0xBEDF4D5FA2FB6BA2,

-	0xBEDAD4F371257BA0,0xBED62A9CDEB0AB32,0xBED1A6DF97B88316,0xBECB100096894E58,

-	0xBEC3E8A76257D275,0xBEBBF6C29A5150C9,0xBEB296292998088E,0xBEA70A10498F0E5E,

-	0xBE99E52D02F887A1,0xBE88C17F4066D432,0xBE702A716CFF56CA,0x3E409F820F781F78,

-	0x3E643EA99B770FE7,0x3E67DE40CDE0A550,0x3E64F4D534A2335C,0x3E5F194536BDDF7A,

-	0x3E5425CEBE1FA40A,0x3E46D7B7CC631E73,0x3E364746B6582E54,0x3E21FC07B13031DE,

-	0x3E064C3D91CF7665,0x3DE224F901A0AFC7,0x3DA97D57859C74A4,0x0000000000000000,

+	 1.000047730261351741631870027, 1.000070326525919428561905988, 1.000026295486963423542192686, 0.999910424773336803383472216,

+	 0.999715744379055859525351480, 0.999433014919733908598686867, 0.999050085771328588712947294, 0.998551121919525108694415394,

+	 0.997915706233591937035498631, 0.997117832692634098457062919, 0.996124815495205595539118804, 0.994896148570364013963285288,

+	 0.993382359323431773923118726, 0.991523909003057091204880180, 0.989250199364479221308954493, 0.986478750833182482793404233,

+	 0.983114620682589257505412661, 0.979050130425507592057954298, 0.974164969358674692756494551, 0.968326735771705471300663248,

+	 0.961391968634788374181709969, 0.953207710646355677042151910, 0.943613628528589098998224927, 0.932444698727279863703643059,

+	 0.919534446669115101968827730, 0.904718706053873278349897191, 0.887839842029686909796737382, 0.868751359331251915563143484,

+	 0.847322794437510795617640724, 0.823444770447693374926245724, 0.797034075604916458779314326, 0.768038612100722994924240083,

+	 0.736442051783192774827568883, 0.702268030364621043126760469, 0.665583712234169455612686761, 0.626502564400415073997407944,

+	 0.585186190589438104403541274, 0.541845095055891845525763983, 0.496738269945924404424886234, 0.450171529567763739621000241,

+	 0.402494548939336449500103754, 0.354096601546017020201162495, 0.305401031227847563620514393, 0.256858534249934655768754510,

+	 0.208939368513054252174399039, 0.162124646097439151226637932, 0.116896901459689991908952322, 0.073730159227936173382822460,

+	 0.033079751373986221452128120,-0.004627847551233893637345762,-0.039004887382349466562470042,-0.069711629260494178961238276,

+	-0.096464776709362487494558991,-0.119044790560825133884925719,-0.137301851759562276722448360,-0.151160268717908163882412964,

+	-0.160621165999489917686204876,-0.165763337555641210308010614,-0.166742199141503621984128358,-0.163786829309547077304642926,

+	-0.157195144771094669211564110,-0.147327312088839507131510231,-0.134597551740997606328775760,-0.119464540741507418974975963,

+	-0.102420664473805989036492292,-0.083980405628003879092702277,-0.064668186778692057781192659,-0.045006002136687713044427284,

+	-0.025501182606377806316722001,-0.006634636085273460347211394, 0.011150108072625494748386643, 0.027456744995838545247979212,

+	 0.041944658451493331552395460, 0.054335772988313046916175608, 0.064419613137017092685532305, 0.072056443764197217194400480,

+	 0.077178424602408784993556878, 0.079788772844964592212413379, 0.079958988468210145938996902, 0.077824255600564926083073658,

+	 0.073577187846729327769246254, 0.067460134194076051827870799, 0.059756303384108616638670242, 0.050779997099921050929260957,

+	 0.040866264989502618099059816, 0.030360306751458156215850437, 0.019606947961234157812304701, 0.008940507097049575288560952,

+	-0.001324648208126466466388882,-0.010902586500777250097526938,-0.019543107356485005243751374,-0.027037657667711743197935803,

+	-0.033223730539404389139335194,-0.037987660680654206091233505,-0.041265784496258707536586741,-0.043043987097204458591725995,

+	-0.043355710312406585404954029,-0.042278543756813086185175621,-0.039929563528408616723819335,-0.036459618831699062979634363,

+	-0.032046794692908199542191738,-0.026889298182776331241905510,-0.021198025763611533928143515,-0.015189070430455576393713457,

+	-0.009076419455364113236806034,-0.003065077316892155564337363, 0.002655175361548794011473662, 0.007915206247809156159256361,

+	 0.012570993866018958726171739, 0.016507022146950881685834034, 0.019638542128970374461838233, 0.021912677934460975809338734,

+	 0.023308395228452325614876273, 0.023835389125096861917540991, 0.023531983633596965932444078, 0.022462165098004915897433875,

+	 0.020711896771322700627759872, 0.018384880003473082210607714, 0.015597939105523964467558962, 0.012476211636472618604631890,

+	 0.009148323764166686397625305, 0.005741721847351755579624832, 0.002378317065490789024989615,-0.000829419425005380466127403,

+	-0.003781796760683148444365242,-0.006394592475568152724341164,-0.008601029202315702004710829,-0.010353009833494400057651852,

+	-0.011621609729198234539637724,-0.012396851839770069853008394,-0.012686815497510708569683935,-0.012516151297987356677543502,

+	-0.011924092281628086154032786,-0.010962065062340150406461348,-0.009691013345942120493781147,-0.008178550345073604815882007,

+	-0.006496056025074358440674072,-0.004715830178801836899959987,-0.002908403455554361104196115,-0.001140096220006421448914247,

+	 0.000529099845866712065883819, 0.002047259427257062253113773, 0.003371840725899812995364213, 0.004470560830528139475981142,

+	 0.005321826318522163493107691, 0.005914733331712991419581993, 0.006248666963769690732566353, 0.006332543236118748190832672,

+	 0.006183747823531677602348910, 0.005826833745009315536356187, 0.005292045316197638814281756, 0.004613737750803969042689978,

+	 0.003828761006839943078355892, 0.002974873016054367744903653, 0.002089241623845963964634098, 0.001207086791118088800120467,

+	 0.000360505313776118753877481,-0.000422490021201840063209965,-0.001118695810940623525803206,-0.001710197865787731110603920,

+	-0.002184605984988852254297109,-0.002535053949380879686342771,-0.002759983640474954029453425,-0.002862739419386348127538611,

+	-0.002851004510552685496799219,-0.002736115017663406229209144,-0.002532289317276390557681642,-0.002255810970882980801693884,

+	-0.001924202080457771161722813,-0.001555421358101014960712005,-0.001167117308478276627506376,-0.000775962090624877551779670,

+	-0.000397086112821087974713435,-0.000043627508742770710237387, 0.000273595371614305691784774, 0.000546286179945486565119606,

+	 0.000768750680536383766867925, 0.000937862797633428843004089, 0.001052928740415311594305625, 0.001115464566897328381120391,

+	 0.001128904823558016723081265, 0.001098261208043675284801166, 0.001029750572351520628011645, 0.000930411077785372455858925,

+	 0.000807724029027989654482000, 0.000669256978018619233528064, 0.000522341243078797709889494, 0.000373794189875729877727689,

+	 0.000229693626208723626408101, 0.000095208625460110475721871,-0.000025511844279469758173208,-0.000129393822077144692462430,

+	-0.000214440509776957504047001,-0.000279687383686450809737456,-0.000325117484787396354272565,-0.000351545144152561614761532,

+	-0.000360476947384593608518510,-0.000353958823942885139873099,-0.000334417806276329982514278,-0.000304506298090264292902779,

+	-0.000266955691183075056582136,-0.000224444953912546549387383,-0.000179488462294699944012469,-0.000134345936549333598141603,

+	-0.000090955956048889888797271,-0.000050893220267083281950406,-0.000015348557788785960678823, 0.000014870297520588306796089,

+	 0.000039319915274267510328903, 0.000057887658269859997505705, 0.000070747063526119185008535, 0.000078305819543209774719408,

+	 0.000081149939344861922907622, 0.000079987451948008292520673, 0.000075594520611004130655058, 0.000068766382254997158183021,

+	 0.000060274927715552435942073, 0.000050834144795034220151546, 0.000041074060306237671633470, 0.000031523273709852359548023,

+	 0.000022599698095009569128290, 0.000014608732178951863478521, 0.000007747790946751235789929, 0.000002115927046159247276264,

+	-0.000002272821614624657917699,-0.000005473727618614671290435,-0.000007594607649309153682893,-0.000008779148282948222000235,

+	-0.000009191289914471795693680,-0.000009001415957147717553273,-0.000008374862616584595860708,-0.000007463035714495605026032,

+	-0.000006397209079216532043657,-0.000005284894977678962862369,-0.000004208528817468251939280,-0.000003226102468093129124012,

+	-0.000002373314390120065336351,-0.000001666778737492929471595,-0.000001107845639559032712541,-0.000000686624974759576246945,

+	-0.000000385868818649388185867,-0.000000184445440432801241354,-0.000000060222272723601931954, 0.000000007740724047001495273,

+	 0.000000037708832885684096027, 0.000000044457942869060847864, 0.000000039034296310091607592, 0.000000028962932871006776366,

+	 0.000000018763994698223029203, 0.000000010636937008622986639, 0.000000005187099504706206719, 0.000000002093670467469700098,

+	 0.000000000648951812097509606, 0.000000000132018063854003986, 0.000000000011591335682393882, 0.000000000000000000000000000,

-	// extra padding needed for interpolation

-	0x0000000000000000

+	 0.000000000000000000000000000 // 8bitbubsy: one extra zero is required for interpolation look-up

};

-const double *get_minblep_table(void) { return (const double *)minblepdata; }

 #define LERP(x, y, z) ((x) + ((y) - (x)) * (z))

 void blepAdd(blep_t *b, double dOffset, double dAmplitude)

@@ -91,9 +87,9 @@

 	double f = dOffset * BLEP_SP;

-	int32_t i = (int32_t)f; // get integer part of f

-	const double *dBlepSrc = get_minblep_table() + i;

-	f -= i; // remove integer part from f

+	int32_t i = (int32_t)f; // 8bitbubsy: get integer part of f

+	const double *dBlepSrc = dMinblepData + i;

+	f -= i; // 8bitbubsy: remove integer part from f

 	i = b->index;

 	for (int32_t n = 0; n < BLEP_NS; n++)