CVEX/simple.C

/*
 * Copyright (c) 2024
 *      Side Effects Software Inc.  All rights reserved.
 *
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 * following conditions are met:
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 * 2. The name of Side Effects Software may not be used to endorse or
 *    promote products derived from this software without specific prior
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 *
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 * OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.  IN
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 *
 *----------------------------------------------------------------------------
 * Sample of the CVEX interface to call VEX.
 *
 * CVEX is most efficient when operating on arrays of data.  The interface
 * allows you to create a VEX function to perform some computation.  Instead of
 * hard-coding the algorithm in your C++ code, you can alter the algorithm by
 * running different VEX code.  It allows flexibility in design of your code.
 */

#include <CVEX/CVEX_Context.h>
#include <UT/UT_Main.h>
#include <UT/UT_Vector3.h>
#include <MOT/MOT_Director.h>

namespace HDK_Sample {

#define SIZE    32

static void
initializeP(UT_Vector3 *P)
{
    int         i;
    uint        seed = 0;
    for (i = 0; i < SIZE; i++)
        P[i].assign(i/(fpreal)SIZE, SYSfastRandom(seed), 1);
}

static void
dumpLen(const fpreal32 *len)
{
    int         i;
    printf("Length = [");
    for (i = 0; i < SIZE; i++)
    {
        printf("%g,", len[i]);
    }
    printf("]\n");
}

}

using namespace HDK_Sample;

int
theMain(int argc, char *argv[])
{
    CVEX_Context        cvex;
    CVEX_Value          *P_val, *len_val;
    UT_Vector3          Pbuffer[SIZE];
    int32               seed = 1;
    fpreal32            len[SIZE];

    cvex.addInput("P", CVEX_TYPE_VECTOR3, true);        // Varying value
    cvex.addInput("seed", CVEX_TYPE_INTEGER, &seed, 1); // Uniform value

    // Pass arguments to CVEX
    if (!cvex.load(argc-1, argv+1))
        return 0;

    // Check to see whether VEX function has a "vector P" parameter
    P_val = cvex.findInput("P", CVEX_TYPE_VECTOR3);
    if (P_val)
    {
        initializeP(Pbuffer);           // Set the values for "P"
        P_val->setTypedData(Pbuffer, SIZE);  // "bind" the buffer to the variable
    }
    // Check to see whether VEX function has a "export float len" parameter
    len_val = cvex.findOutput("len", CVEX_TYPE_FLOAT);
    if (len_val)
        len_val->setTypedData(len, SIZE);

    // Run the CVEX program
    cvex.run(SIZE, false);

    if (len_val)
        dumpLen(len);

    return 0;
}
UT_MAIN(theMain);