view dmlerp.c @ 510:43ea59887c69

Start work on making C64 formats encoding possible by changing DMDecodeOps to DMEncDecOps and adding fields and op enums for custom encode functions, renaming, etc. Split generic op sanity checking into a separate function in preparation for its use in generic encoding function.
author Matti Hamalainen <ccr@tnsp.org>
date Mon, 19 Nov 2012 15:06:01 +0200
parents 72813cece1ba
children
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#include "dmlib.h"

void dmLerpInit(DMLerpContext *ctx, DMFloat start, DMFloat end, DMFloat nsteps)
{
    ctx->start = start;
    ctx->end = end;
    ctx->nsteps = nsteps;
}


DMFloat dmCatmullRom(const DMFloat t, const DMFloat p0, const DMFloat p1, const DMFloat p2, const DMFloat p3)
{
    const DMFloat q = t * t;
    return (
        (2 * p1) +
        (-p0 + p2) * t +
        (2 * p0 - 5 * p1 + 4 * p2 - p3) * q +
        (   -p0 + 3 * p1 - 3 * p2 + p3) * q * t
        ) * 0.5f;
}