| 1 | /* |
| 2 | * fixedPt.h |
| 3 | * |
| 4 | * [Generated from fixedPt, 25 September 1996] |
| 5 | */ |
| 6 | |
| 7 | #if !defined(__CC_NORCROFT) || !defined(__arm) |
| 8 | #error You must use the Norcroft ARM Compiler for Sapphire programs |
| 9 | #endif |
| 10 | |
| 11 | #pragma include_only_once |
| 12 | #pragma force_top_level |
| 13 | |
| 14 | #ifndef __fixedPt_h |
| 15 | #define __fixedPt_h |
| 16 | |
| 17 | #ifndef __sapphire_h |
| 18 | #include "sapphire.h" |
| 19 | #endif |
| 20 | |
| 21 | /*----- Overview ----------------------------------------------------------* |
| 22 | * |
| 23 | * Functions provided: |
| 24 | * |
| 25 | * fxp_atan |
| 26 | * fxp_pol |
| 27 | * fxp_sin |
| 28 | * fxp_cos |
| 29 | */ |
| 30 | |
| 31 | /* --- fxp_atan --- * |
| 32 | * |
| 33 | * On entry: R0 == x, in 16.16 fixed point form |
| 34 | * |
| 35 | * On exit: R0 == arctan x, in degrees, in 16.16 fixed point |
| 36 | * |
| 37 | * Use: Calculates arctan x, hopefully fairly swiftly. The |
| 38 | * accuracy of the result is open to doubt, although |
| 39 | * it's usually good to about 3 significant figures. |
| 40 | * It uses a small lookup table and linear interpolation |
| 41 | * to calculate the result. |
| 42 | */ |
| 43 | |
| 44 | extern routine fxp_atan; |
| 45 | |
| 46 | /* --- fxp_pol --- * |
| 47 | * |
| 48 | * On entry: R0 == x coordinate |
| 49 | * R1 == y coordinate |
| 50 | * |
| 51 | * On exit: R0 == angle in degrees, in 16.16 form |
| 52 | * |
| 53 | * Use: Calculates the angle a vector makes with the +ve x axis. |
| 54 | * The angle is given in degrees, rather than radians, |
| 55 | * although this isn't really overly significant; it just |
| 56 | * makes it slightly easier to work with, because it's |
| 57 | * bigger. |
| 58 | * |
| 59 | * This routine uses the arctan table and linear |
| 60 | * interpolation, so it's fairly quick, but the accuracy |
| 61 | * of its results is restricted to about 3 significant figures. |
| 62 | */ |
| 63 | |
| 64 | extern routine fxp_pol; |
| 65 | |
| 66 | /* --- fxp_sin --- * |
| 67 | * |
| 68 | * On entry: R0 == angle in degrees, in 16.16 form |
| 69 | * |
| 70 | * On exit: R0 == sin of angle, in 16.16 form |
| 71 | * |
| 72 | * Use: Calculates a sin of an angle with a degree of swiftness and |
| 73 | * a lot less accuracy. |
| 74 | */ |
| 75 | |
| 76 | extern routine fxp_sin; |
| 77 | |
| 78 | /* --- fxp_cos --- * |
| 79 | * |
| 80 | * On entry: R0 == angle in degrees, in 16.16 form |
| 81 | * |
| 82 | * On exit: R0 == cos of angle, in 16.16 form |
| 83 | * |
| 84 | * Use: Calculates a cos of an angle with a degree of swiftness and |
| 85 | * a lot less accuracy. |
| 86 | */ |
| 87 | |
| 88 | extern routine fxp_cos; |
| 89 | |
| 90 | /*----- That's all, folks -------------------------------------------------*/ |
| 91 | |
| 92 | #endif |