/*

 *  File:       DZSpace.c

 *

 *  Contents:   Submits the spacejunk.

 *

 *  Copyright © 1996 Apple Computer, Inc.

 */

#include <assert.h>

#include <Quickdraw.h>

#include "QD3D.h"

#include "QD3DGeometry.h"

#include "QD3DShader.h"

#include "QD3DView.h"

#include "DZSpace.h"

#ifndef SPACE_JUNK_IS_LINES

#define SPACE_JUNK_IS_LINES 1

#endif

#define SPACE_INTERVAL      2.0         // Grid cell size

#define SPACE_CUBE          3           // Half side of the cube of cells

#define SPACE_SPREAD1       0.0001      // Mulitplier to Random for line start

#define SPACE_SPREAD2       0.00002     // Mulitplier to Random for line length

static TQ3AttributeSet  gSpaceColor         = NULL;

/* =============================================================================

 *      Space_Init (external)

 *

 *  Initializes the space stuff.

 * ========================================================================== */

void Space_Init(

    void)

{

    gSpaceColor = Q3AttributeSet_New();

}

/* =============================================================================

 *      Space_Exit (external)

 *

 *  Prepares for exit.

 * ========================================================================== */

void Space_Exit(

    void)

{

    if (gSpaceColor != NULL)

    {

        Q3Object_Dispose(gSpaceColor);

        gSpaceColor = NULL;

    }

}

/* =============================================================================

 *      Space_Submit (external)

 *

 *  Submits all the 3D geometry of the spacejunk.

 * ========================================================================== */

void Space_Submit(

    TQ3ViewObject       inView,

    const TQ3Point3D*   inPosition,

    const TQ3Vector3D*  inDirection)

{

    long                x;

    long                y;

    long                z;

    long                loX;

    long                loY;

    long                loZ;

    long                hiX;

    long                hiY;

    long                hiZ;

    float               px;

    float               py;

    float               pz;

    TQ3ColorRGB         color;

#if SPACE_JUNK_IS_LINES

    TQ3LineData         lineData;

#else   // !SPACE_JUNK_IS_LINES

    TQ3PointData        pointData;

#endif

    assert(inView != NULL);

    assert(inPosition != NULL);

    assert(inDirection != NULL);

    // Find the center grid cell

    px = inPosition->x + inDirection->x*SPACE_INTERVAL*SPACE_CUBE;

    py = inPosition->y + inDirection->y*SPACE_INTERVAL*SPACE_CUBE;

    pz = inPosition->z + inDirection->z*SPACE_INTERVAL*SPACE_CUBE;

    x = (px + 0.5*SPACE_INTERVAL)/SPACE_INTERVAL;

    y = (py + 0.5*SPACE_INTERVAL)/SPACE_INTERVAL;

    z = (pz + 0.5*SPACE_INTERVAL)/SPACE_INTERVAL;

    // Find the range to cover

    loX = x - SPACE_CUBE;

    loY = y - SPACE_CUBE;

    loZ = z - SPACE_CUBE;

    hiX = loX + 2*SPACE_CUBE;

    hiY = loY + 2*SPACE_CUBE;

    hiZ = loZ + 2*SPACE_CUBE;

#if SPACE_JUNK_IS_LINES

    // Set up the line data

    lineData.vertices[0].attributeSet   = NULL;

    lineData.vertices[1].attributeSet   = NULL;

    lineData.lineAttributeSet           = gSpaceColor;

#else   // !SPACE_JUNK_IS_LINES

    pointData.pointAttributeSet         = gSpaceColor;

#endif

    // Do the cube

    for (x = loX; x <= hiX; x++)

    {

        px = (x+0.5)*SPACE_INTERVAL;

        for (y = loY; y <= hiY; y++)

        {

            py = (y+0.5)*SPACE_INTERVAL;

            for (z = loZ; z <= hiZ; z++)

            {

                pz = (z+0.5)*SPACE_INTERVAL;

                // Make Random() repeatable based on cell index

                qd.randSeed = x^y^z;

                // Set up the line color -- blend between purple and green

                color.b = ((unsigned short) Random()) * (1.0/65535.0);

                color.r = 0.4*color.b;

                color.g = 0.8*(1.0-color.b);

                Q3AttributeSet_Add(gSpaceColor, kQ3AttributeTypeDiffuseColor, &color);

#if SPACE_JUNK_IS_LINES

                // Set up the endpoints

                lineData.vertices[0].point.x = px + Random()*SPACE_SPREAD1;

                lineData.vertices[0].point.y = py + Random()*SPACE_SPREAD1;

                lineData.vertices[0].point.z = pz + Random()*SPACE_SPREAD1;

                lineData.vertices[1].point.x = lineData.vertices[0].point.x + Random()*SPACE_SPREAD2;

                lineData.vertices[1].point.y = lineData.vertices[0].point.y + Random()*SPACE_SPREAD2;

                lineData.vertices[1].point.z = lineData.vertices[0].point.z + Random()*SPACE_SPREAD2;

                // Submit the line

                Q3Line_Submit(&lineData, inView);

#else   // !SPACE_JUNK_IS_LINES

                pointData.point.x = px + Random()*SPACE_SPREAD1;

                pointData.point.y = py + Random()*SPACE_SPREAD1;

                pointData.point.z = pz + Random()*SPACE_SPREAD1;

                Q3Point_Submit(&pointData, inView);

#endif          

            }

        }

    }

}