/
mesh_gen.cpp
1546 lines (1154 loc) · 52.7 KB
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mesh_gen.cpp
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/************************************************************************/
/* */
/* This file is part of VDrift. */
/* */
/* VDrift is free software: you can redistribute it and/or modify */
/* it under the terms of the GNU General Public License as published by */
/* the Free Software Foundation, either version 3 of the License, or */
/* (at your option) any later version. */
/* */
/* VDrift is distributed in the hope that it will be useful, */
/* but WITHOUT ANY WARRANTY; without even the implied warranty of */
/* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the */
/* GNU General Public License for more details. */
/* */
/* You should have received a copy of the GNU General Public License */
/* along with VDrift. If not, see <http://www.gnu.org/licenses/>. */
/* */
/************************************************************************/
#include "mesh_gen.h"
#include "vertexarray.h"
#include "mathvector.h"
static double sinD(double degrees)
{
return (double) sin(degrees * M_PI / 180.000f);
}
static double cosD(double degrees)
{
return (double) cos(degrees * M_PI / 180.000f);
}
namespace MESHGEN
{
/////////////////////////////////////////////////////////////////////////////////////////////
// mg_tire
void mg_tire(VERTEXARRAY & tire, float sectionWidth_mm, float aspectRatio, float rimDiameter_in)
{
// configurable parameters - set to defaults
int segmentsAround = 32;
float innerRadius = 0.65f;
float innerWidth = 0.60f;
float sidewallRadius = 0.75f;
float sidewallBulge = 0.05f; // bulge from tread
float shoulderRadius = 0.95f;
float shoulderBulge = 0.00f; // bulge from tread
float treadRadius = 1.00f;
float treadWidth = 0.60f;
float vertexNormalLength = 0.025f;
// use this to build a tire based on the tire code passed to this function
// if the code under this if doesn't happen, then the parameters are meaningless
if (true)
{
// use function parameters - comment out this section
float sectionWidth_m = sectionWidth_mm / 1000.0f;
float rimRadius_m = rimDiameter_in * 0.0254f * 0.5;
innerRadius = rimRadius_m;
// fudge number: based on 15 inch rims on my car and truck - this number has to be synchronized with the one in wheel_edge
innerRadius *= 1.08f;
treadWidth = sectionWidth_m - (sectionWidth_m / 4.0f); // subtract 1/8th from section width, to get the tread width (not really sure, looks ok though)
// aspect ratio is a little strange, but i didn't make this stuff up
// en.wikipedia.org/wiki/Tire_code
// auto.howstuffworks.com/tire2.htm
if (aspectRatio <= 0) // aspect ratio ommitted default to 82%
{
aspectRatio = 82.0f;
}
////////////////////////////////////////////////////////
// this isn't iso standard, but it is sorta important
// math says a percent should be less than 1
// but the tire code has it as a whole number
// could use a uint, but floats are always best for 3d
if (aspectRatio > 1) // then he gave us a whole number
{
aspectRatio = aspectRatio / 100.0f;
}
// if he gave us a large number (specifically over 200) we need to assume that he told us the diameter of the tire in mm
if (aspectRatio > 2) // he gave us a mm diameter for the entire tire (instead of a % of the section width)
{
treadRadius = aspectRatio / 2000.0f;
}
else // otherwise: he gave us the normal percent
{
treadRadius = sectionWidth_m * aspectRatio + rimRadius_m;
}
// fudge some values by what looks ok.
innerWidth = treadWidth;
sidewallBulge = innerWidth * 0.050f;
shoulderBulge = treadWidth * 0.050f;
float totalSidewallHeight = sectionWidth_m * aspectRatio;
sidewallRadius = totalSidewallHeight/2.0f + rimRadius_m;
shoulderRadius = totalSidewallHeight/1.1f + rimRadius_m;
}
// non-configurable parameters
int vertexRings = 8;
float angleIncrement = 360.0f / (float) segmentsAround;
/////////////////////////////////////
//
// vertices (temporary data)
//
int vertexesAround = segmentsAround + 1;
int vertexCount = vertexesAround * vertexRings;
int vertexFloatCount = vertexCount * 3; // * 3 cause there are 3 floats in a vertex
std::vector<float> vertexData;
vertexData.resize(vertexFloatCount);
// Right-side, Inner Ring
for (int lv=0 ; lv<vertexesAround ; lv++)
{
vertexData[(lv+vertexesAround * 0) * 3 + 0] = 1.0f * (innerWidth / 2.0f);
vertexData[(lv+vertexesAround * 0) * 3 + 1] = innerRadius * cosD(angleIncrement * lv);
vertexData[(lv+vertexesAround * 0) * 3 + 2] = innerRadius * sinD(angleIncrement * lv);
}
// Right-side, Sidewall Ring
for (int lv=0 ; lv<vertexesAround ; lv++)
{
vertexData[(lv+vertexesAround * 1) * 3 + 0] = 1.0f * (treadWidth / 2.0f + sidewallBulge);
vertexData[(lv+vertexesAround * 1) * 3 + 1] = sidewallRadius * cosD(angleIncrement * lv);
vertexData[(lv+vertexesAround * 1) * 3 + 2] = sidewallRadius * sinD(angleIncrement * lv);
}
// Right-side, Shoulder Ring
for (int lv=0 ; lv<vertexesAround ; lv++)
{
vertexData[(lv+vertexesAround * 2) * 3 + 0] = 1.0f * (treadWidth / 2.0f + shoulderBulge);
vertexData[(lv+vertexesAround * 2) * 3 + 1] = shoulderRadius * cosD(angleIncrement * lv);
vertexData[(lv+vertexesAround * 2) * 3 + 2] = shoulderRadius * sinD(angleIncrement * lv);
}
// Right-side, Tread Ring
for (int lv=0 ; lv<vertexesAround ; lv++)
{
vertexData[(lv+vertexesAround * 3) * 3 + 0] = 1.0f * (treadWidth / 2.0f);
vertexData[(lv+vertexesAround * 3) * 3 + 1] = treadRadius * cosD(angleIncrement * lv);
vertexData[(lv+vertexesAround * 3) * 3 + 2] = treadRadius * sinD(angleIncrement * lv);
}
// Left-side, Tread Ring
for (int lv=0 ; lv<vertexesAround ; lv++)
{
vertexData[(lv+vertexesAround * 4) * 3 + 0] = -1.0f * (treadWidth / 2.0f);
vertexData[(lv+vertexesAround * 4) * 3 + 1] = treadRadius * cosD(angleIncrement * lv);
vertexData[(lv+vertexesAround * 4) * 3 + 2] = treadRadius * sinD(angleIncrement * lv);
}
// Left-side, Shoulder Ring
for (int lv=0 ; lv<vertexesAround ; lv++)
{
vertexData[(lv+vertexesAround * 5) * 3 + 0] = -1.0f * (treadWidth / 2.0f + shoulderBulge);
vertexData[(lv+vertexesAround * 5) * 3 + 1] = shoulderRadius * cosD(angleIncrement * lv);
vertexData[(lv+vertexesAround * 5) * 3 + 2] = shoulderRadius * sinD(angleIncrement * lv);
}
// Left-side, Sidewall Ring
for (int lv=0 ; lv<vertexesAround ; lv++)
{
vertexData[(lv+vertexesAround * 6) * 3 + 0] = -1.0f * (treadWidth / 2.0f + sidewallBulge);
vertexData[(lv+vertexesAround * 6) * 3 + 1] = sidewallRadius * cosD(angleIncrement * lv);
vertexData[(lv+vertexesAround * 6) * 3 + 2] = sidewallRadius * sinD(angleIncrement * lv);
}
// Left-side, Inner Ring
for (int lv=0 ; lv<vertexesAround ; lv++)
{
vertexData[(lv+vertexesAround * 7) * 3 + 0] = -1.0f * (innerWidth / 2.0f);
vertexData[(lv+vertexesAround * 7) * 3 + 1] = innerRadius * cosD(angleIncrement * lv);
vertexData[(lv+vertexesAround * 7) * 3 + 2] = innerRadius * sinD(angleIncrement * lv);
}
/////////////////////////////////////
//
// now let's build triangles
//
int triVIndexCount = 2 * segmentsAround * (vertexRings-1) * 3; // 2 * triangles make a square, * 3 indexes in a triangle
std::vector<int> triData;
triData.resize(triVIndexCount);
int triIndex = 0;
for (int circleSegment=0; circleSegment<segmentsAround; circleSegment++)
{
// 1st triangle (Right-side - Inner to Sidewall)
triData[ (triIndex+0)*3 + 0 ] = circleSegment;
triData[ (triIndex+0)*3 + 1 ] = circleSegment+vertexesAround;
triData[ (triIndex+0)*3 + 2 ] = circleSegment+1;
// 2nd triangle
triData[ (triIndex+1)*3 + 0 ] = circleSegment+vertexesAround;
triData[ (triIndex+1)*3 + 1 ] = circleSegment+vertexesAround+1;
triData[ (triIndex+1)*3 + 2 ] = circleSegment+1;
// 3rd triangle (Right-side - Sidewall to shoulder)
triData[ (triIndex+2)*3 + 0 ] = circleSegment+vertexesAround*1;
triData[ (triIndex+2)*3 + 1 ] = circleSegment+vertexesAround*2;
triData[ (triIndex+2)*3 + 2 ] = circleSegment+vertexesAround*1+1;
// 4th triangle
triData[ (triIndex+3)*3 + 0 ] = circleSegment+vertexesAround*2;
triData[ (triIndex+3)*3 + 1 ] = circleSegment+vertexesAround*2+1;
triData[ (triIndex+3)*3 + 2 ] = circleSegment+vertexesAround*1+1;
// 5th triangle (Right-side - Shoulder to Tread)
triData[ (triIndex+4)*3 + 0 ] = circleSegment+vertexesAround*2;
triData[ (triIndex+4)*3 + 1 ] = circleSegment+vertexesAround*3;
triData[ (triIndex+4)*3 + 2 ] = circleSegment+vertexesAround*2+1;
// 6th triangle
triData[ (triIndex+5)*3 + 0 ] = circleSegment+vertexesAround*3;
triData[ (triIndex+5)*3 + 1 ] = circleSegment+vertexesAround*3+1;
triData[ (triIndex+5)*3 + 2 ] = circleSegment+vertexesAround*2+1;
//////////////////////////////////////////////////////////////
// 7th triangle (Right-side Tread to Left-side Tread)
triData[ (triIndex+6)*3 + 0 ] = circleSegment+vertexesAround*3;
triData[ (triIndex+6)*3 + 1 ] = circleSegment+vertexesAround*4;
triData[ (triIndex+6)*3 + 2 ] = circleSegment+vertexesAround*3+1;
// 8th triangle
triData[ (triIndex+7)*3 + 0 ] = circleSegment+vertexesAround*4;
triData[ (triIndex+7)*3 + 1 ] = circleSegment+vertexesAround*4+1;
triData[ (triIndex+7)*3 + 2 ] = circleSegment+vertexesAround*3+1;
/////////////////////////////////////////////////////////////
// 9th triangle (Left-side - Tread to Shoulder)
triData[ (triIndex+8)*3 + 0 ] = circleSegment+vertexesAround*4;
triData[ (triIndex+8)*3 + 1 ] = circleSegment+vertexesAround*5;
triData[ (triIndex+8)*3 + 2 ] = circleSegment+vertexesAround*4+1;
// 10th triangle
triData[ (triIndex+9)*3 + 0 ] = circleSegment+vertexesAround*5;
triData[ (triIndex+9)*3 + 1 ] = circleSegment+vertexesAround*5+1;
triData[ (triIndex+9)*3 + 2 ] = circleSegment+vertexesAround*4+1;
// 11th triangle (Left-side - Shoulder to Sidewall)
triData[ (triIndex+10)*3 + 0 ] = circleSegment+vertexesAround*5;
triData[ (triIndex+10)*3 + 1 ] = circleSegment+vertexesAround*6;
triData[ (triIndex+10)*3 + 2 ] = circleSegment+vertexesAround*5+1;
// 12th triangle
triData[ (triIndex+11)*3 + 0 ] = circleSegment+vertexesAround*6;
triData[ (triIndex+11)*3 + 1 ] = circleSegment+vertexesAround*6+1;
triData[ (triIndex+11)*3 + 2 ] = circleSegment+vertexesAround*5+1;
// 13th triangle (Left-side - Sidewall to Inner)
triData[ (triIndex+12)*3 + 0 ] = circleSegment+vertexesAround*6;
triData[ (triIndex+12)*3 + 1 ] = circleSegment+vertexesAround*7;
triData[ (triIndex+12)*3 + 2 ] = circleSegment+vertexesAround*6+1;
// 14th triangle
triData[ (triIndex+13)*3 + 0 ] = circleSegment+vertexesAround*7;
triData[ (triIndex+13)*3 + 1 ] = circleSegment+vertexesAround*7+1;
triData[ (triIndex+13)*3 + 2 ] = circleSegment+vertexesAround*6+1;
triIndex +=14;
}
///////////////////////////////////////////////////////////
//
// Texture Coordinates
//
// the tread pattern should always take up the middle 33%
// of the texture
// tried writting distance calculation support to get the
// sides of the tire to always have even xyz <-> uv space
// but it was sorta tedious. and this hard coded approach
// insures any tire texture will work ok on any size tire.
// though wider tires will experience more tread stretching
// unless they also have a texture with a more appropriate
// resolution.
int texCoordFloats = vertexCount * 2;
std::vector<float> texData;
texData.resize(texCoordFloats);
for ( int uvl=0 ; uvl< vertexCount ; uvl++ )
{
// U coord
float u = uvl % vertexesAround;
u = u / segmentsAround;
texData[ uvl * 2 ] = u;
// V coord
float v = 0.00f;
// v = floor ( uvl * + 1 / vertexesAround );
// v = v / (vertexRings-1);
if ( uvl < vertexesAround*1 )
v = 0.00f;
else if ( uvl < vertexesAround*2 )
v = 0.10f;
else if ( uvl < vertexesAround*3 )
v = 0.25f;
else if ( uvl < vertexesAround*4 )
v = 0.333333333f;
else if ( uvl < vertexesAround*5 )
v = 0.666666666f;
else if ( uvl < vertexesAround*6 )
v = 0.75f;
else if ( uvl < vertexesAround*7 )
v = 0.90f;
else if ( uvl < vertexesAround*8 )
v = 1.00f;
else
{
// shouldn't be able to get here
// maybe put an error message here
// "tiregen error: accessing code that shouldn't be reachable"
assert(0);
}
texData[ uvl * 2 + 1 ] = v;
// so for the very last segment it will need something a little special
// otherwise it draws the entire texture in that tiny last segment space
/*if ( (uvl % segmentsAround == 0) && (uvl > vertexRings * 8) )
{
*u = 1.0f;
}*/
}
//////////////////////////////////////////////
// build some vertex normals
std::vector<float> normalData;
normalData.resize(vertexFloatCount);
MATHVECTOR <float, 3> tri1Edge; // one of the edges of a triangle that goes around the tire's circle
MATHVECTOR <float, 3> tri2Edge; // one of the edges of a triangle that goes around the tire's circle
MATHVECTOR <float, 3> triUpEdge; // one of the edges that wraps around the tire's tread which both faces share, not used on the last vertex ring
MATHVECTOR <float, 3> triDownEdge; // the other edges that wraps around the tire's tread which both faces share, not used on the first vertex ring
for (int nlv=0 ; nlv<vertexCount ; nlv++)
{
/*// one way, not too bad, but not accurate
// this one is messed up
normalData[nlv*3 + 0] = vertexData[nlv*3 +0] * 0.15f; //0.05f;
// these other 2 are actually in the correct direction since its a cylinder
normalData[nlv*3 + 1] = vertexData[nlv*3 + 1] * 0.15f;
normalData[nlv*3 + 2] = vertexData[nlv*3 + 2] * 0.15f;*/
// this is gonna be grizzly
if ( nlv < vertexesAround*1 ) // first ring of vertexes
{
///////////////////////////////////////////////////
// first ring of vertexes
if ((nlv % vertexesAround) == 0 ) // first vertex
{
tri1Edge.Set(
vertexData[nlv*3 ] - vertexData[(nlv+1)*3 ],
vertexData[nlv*3 +1] - vertexData[(nlv+1)*3 +1],
vertexData[nlv*3 +2] - vertexData[(nlv+1)*3 +2]
);
tri2Edge.Set(
vertexData[nlv*3 ] - vertexData[(nlv+segmentsAround-1)*3 ],
vertexData[nlv*3 +1] - vertexData[(nlv+segmentsAround-1)*3 +1],
vertexData[nlv*3 +2] - vertexData[(nlv+segmentsAround-1)*3 +2]
);
triUpEdge.Set(
vertexData[nlv*3 ] - vertexData[(nlv+segmentsAround+1)*3 ],
vertexData[nlv*3 +1] - vertexData[(nlv+segmentsAround+1)*3 +1],
vertexData[nlv*3 +2] - vertexData[(nlv+segmentsAround+1)*3 +2]
);
}
else if ((nlv % vertexesAround) == segmentsAround ) // first ring, last vertex
{
tri1Edge.Set(
vertexData[nlv*3 ] - vertexData[(nlv-segmentsAround+1)*3 ],
vertexData[nlv*3 +1] - vertexData[(nlv-segmentsAround+1)*3 +1],
vertexData[nlv*3 +2] - vertexData[(nlv-segmentsAround+1)*3 +2]
);
tri2Edge.Set(
vertexData[nlv*3 ] - vertexData[(nlv-1)*3 ],
vertexData[nlv*3 +1] - vertexData[(nlv-1)*3 +1],
vertexData[nlv*3 +2] - vertexData[(nlv-1)*3 +2]
);
triUpEdge.Set(
vertexData[nlv*3 ] - vertexData[(nlv+segmentsAround+1)*3 ],
vertexData[nlv*3 +1] - vertexData[(nlv+segmentsAround+1)*3 +1],
vertexData[nlv*3 +2] - vertexData[(nlv+segmentsAround+1)*3 +2]
);
}
else // first ring, most vertexes
{
tri1Edge.Set(
vertexData[nlv*3 ] - vertexData[(nlv+1)*3 ],
vertexData[nlv*3 +1] - vertexData[(nlv+1)*3 +1],
vertexData[nlv*3 +2] - vertexData[(nlv+1)*3 +2]
);
tri2Edge.Set(
vertexData[nlv*3 ] - vertexData[(nlv-1)*3 ],
vertexData[nlv*3 +1] - vertexData[(nlv-1)*3 +1],
vertexData[nlv*3 +2] - vertexData[(nlv-1)*3 +2]
);
triUpEdge.Set(
vertexData[nlv*3 ] - vertexData[(nlv+segmentsAround+1)*3 ],
vertexData[nlv*3 +1] - vertexData[(nlv+segmentsAround+1)*3 +1],
vertexData[nlv*3 +2] - vertexData[(nlv+segmentsAround+1)*3 +2]
);
/*normalData[nlv*3 + 0] = vertexData[nlv*3 +0] * 0.015f; //0.05f;
// these other 2 are actually in the correct direction since its a cylinder
normalData[nlv*3 + 1] = vertexData[nlv*3 + 1] * 0.015f;
normalData[nlv*3 + 2] = vertexData[nlv*3 + 2] * 0.015f;
continue;*/
}
MATHVECTOR <float, 3> faceNormal1 = triUpEdge.cross(tri1Edge);
MATHVECTOR <float, 3> faceNormal2 = tri2Edge.cross(triUpEdge);
MATHVECTOR <float, 3> vNormal = faceNormal1 + faceNormal2;
vNormal = vNormal.Normalize();
vNormal = vNormal * vertexNormalLength;
normalData[nlv*3 + 0] = vNormal[0];
normalData[nlv*3 + 1] = vNormal[1];
normalData[nlv*3 + 2] = vNormal[2];
}
///////////////////////////////////////////////////
// last ring of vertexes
else if ( nlv >= vertexesAround*7 )
{
if ((nlv % vertexesAround) == 0 ) // last ring, first vertex
{
tri1Edge.Set(
vertexData[nlv*3 ] - vertexData[(nlv+1)*3 ],
vertexData[nlv*3 +1] - vertexData[(nlv+1)*3 +1],
vertexData[nlv*3 +2] - vertexData[(nlv+1)*3 +2]
);
tri2Edge.Set(
vertexData[nlv*3 ] - vertexData[(nlv+segmentsAround)*3 ],
vertexData[nlv*3 +1] - vertexData[(nlv+segmentsAround)*3 +1],
vertexData[nlv*3 +2] - vertexData[(nlv+segmentsAround)*3 +2]
);
triUpEdge.Set(
vertexData[nlv*3 ] - vertexData[(nlv-segmentsAround-1)*3 ],
vertexData[nlv*3 +1] - vertexData[(nlv-segmentsAround-1)*3 +1],
vertexData[nlv*3 +2] - vertexData[(nlv-segmentsAround-1)*3 +2]
);
}
else if ( nlv == vertexCount-1 ) // last ring, last vertex (last vertex in mesh)
{
tri2Edge.Set(
vertexData[nlv*3 ] - vertexData[(nlv-1)*3 ],
vertexData[nlv*3 +1] - vertexData[(nlv-1)*3 +1],
vertexData[nlv*3 +2] - vertexData[(nlv-1)*3 +2]
);
tri1Edge.Set(
vertexData[nlv*3 ] - vertexData[(nlv-segmentsAround)*3 ],
vertexData[nlv*3 +1] - vertexData[(nlv-segmentsAround)*3 +1],
vertexData[nlv*3 +2] - vertexData[(nlv-segmentsAround)*3 +2]
);
triUpEdge.Set(
vertexData[nlv*3 ] - vertexData[(nlv-segmentsAround-1)*3 ],
vertexData[nlv*3 +1] - vertexData[(nlv-segmentsAround-1)*3 +1],
vertexData[nlv*3 +2] - vertexData[(nlv-segmentsAround-1)*3 +2]
);
}
else // last ring, most vertexes
{
tri2Edge.Set(
vertexData[nlv*3 ] - vertexData[(nlv+1)*3 ],
vertexData[nlv*3 +1] - vertexData[(nlv+1)*3 +1],
vertexData[nlv*3 +2] - vertexData[(nlv+1)*3 +2]
);
tri1Edge.Set(
vertexData[nlv*3 ] - vertexData[(nlv-1)*3 ],
vertexData[nlv*3 +1] - vertexData[(nlv-1)*3 +1],
vertexData[nlv*3 +2] - vertexData[(nlv-1)*3 +2]
);
triUpEdge.Set(
vertexData[nlv*3 ] - vertexData[(nlv-segmentsAround+1)*3 ],
vertexData[nlv*3 +1] - vertexData[(nlv-segmentsAround+1)*3 +1],
vertexData[nlv*3 +2] - vertexData[(nlv-segmentsAround+1)*3 +2]
);
/*normalData[nlv*3 + 0] = vertexData[nlv*3 +0] * 0.015f; //0.05f;
// these other 2 are actually in the correct direction since its a cylinder
normalData[nlv*3 + 1] = vertexData[nlv*3 + 1] * 0.015f;
normalData[nlv*3 + 2] = vertexData[nlv*3 + 2] * 0.015f;
continue;*/
}
// all actual normal calculation takes place here
MATHVECTOR <float, 3> faceNormal1 = tri1Edge.cross(triUpEdge);
MATHVECTOR <float, 3> faceNormal2 = triUpEdge.cross(tri2Edge);
MATHVECTOR <float, 3> vNormal = faceNormal1 + faceNormal2;
vNormal = vNormal.Normalize();
vNormal = vNormal * vertexNormalLength;
normalData[nlv*3 + 0] = vNormal[0];
normalData[nlv*3 + 1] = vNormal[1];
normalData[nlv*3 + 2] = vNormal[2];
}
///////////////////////////////////////////////////
// this is for the majority of the rings
else
{
///////////////////////////////////////////////////
// first vertex in ring
if ((nlv % vertexesAround) == 0 )
{
tri1Edge.Set(
vertexData[nlv*3 ] - vertexData[(nlv+1)*3 ],
vertexData[nlv*3 +1] - vertexData[(nlv+1)*3 +1],
vertexData[nlv*3 +2] - vertexData[(nlv+1)*3 +2]
);
tri2Edge.Set(
vertexData[nlv*3 ] - vertexData[(nlv+segmentsAround-1)*3 ],
vertexData[nlv*3 +1] - vertexData[(nlv+segmentsAround-1)*3 +1],
vertexData[nlv*3 +2] - vertexData[(nlv+segmentsAround-1)*3 +2]
);
triUpEdge.Set(
vertexData[nlv*3 ] - vertexData[(nlv+segmentsAround+1)*3 ],
vertexData[nlv*3 +1] - vertexData[(nlv+segmentsAround+1)*3 +1],
vertexData[nlv*3 +2] - vertexData[(nlv+segmentsAround+1)*3 +2]
);
triDownEdge.Set(
vertexData[(nlv-segmentsAround-1)*3 ] - vertexData[nlv*3 ],
vertexData[(nlv-segmentsAround-1)*3 +1] - vertexData[nlv*3 +1],
vertexData[(nlv-segmentsAround-1)*3 +2] - vertexData[nlv*3 +2]
);
/*normalData[nlv*3 + 0] = vertexData[nlv*3 +0] * 0.015f; //0.05f;
// these other 2 are actually in the correct direction since its a cylinder
normalData[nlv*3 + 1] = vertexData[nlv*3 + 1] * 0.015f;
normalData[nlv*3 + 2] = vertexData[nlv*3 + 2] * 0.015f;
continue;*/
}
else if ((nlv % vertexesAround ) == segmentsAround ) // last vertex in ring
{
tri1Edge.Set(
vertexData[nlv*3 ] - vertexData[(nlv-segmentsAround+1)*3 ],
vertexData[nlv*3 +1] - vertexData[(nlv-segmentsAround+1)*3 +1],
vertexData[nlv*3 +2] - vertexData[(nlv-segmentsAround+1)*3 +2]
);
tri2Edge.Set(
vertexData[nlv*3 ] - vertexData[(nlv-1)*3 ],
vertexData[nlv*3 +1] - vertexData[(nlv-1)*3 +1],
vertexData[nlv*3 +2] - vertexData[(nlv-1)*3 +2]
);
triUpEdge.Set(
vertexData[nlv*3 ] - vertexData[(nlv+segmentsAround+1)*3 ],
vertexData[nlv*3 +1] - vertexData[(nlv+segmentsAround+1)*3 +1],
vertexData[nlv*3 +2] - vertexData[(nlv+segmentsAround+1)*3 +2]
);
triDownEdge.Set(
vertexData[(nlv-segmentsAround-1)*3 ] - vertexData[nlv*3 ],
vertexData[(nlv-segmentsAround-1)*3 +1] - vertexData[nlv*3 +1],
vertexData[(nlv-segmentsAround-1)*3 +2] - vertexData[nlv*3 +2]
);
/*normalData[nlv*3 + 0] = vertexData[nlv*3 +0] * 0.015f; //0.05f;
// these other 2 are actually in the correct direction since its a cylinder
normalData[nlv*3 + 1] = vertexData[nlv*3 + 1] * 0.015f;
normalData[nlv*3 + 2] = vertexData[nlv*3 + 2] * 0.015f;
continue;*/
}
else // most vertexes
{
tri1Edge.Set(
vertexData[nlv*3 ] - vertexData[(nlv+1)*3 ],
vertexData[nlv*3 +1] - vertexData[(nlv+1)*3 +1],
vertexData[nlv*3 +2] - vertexData[(nlv+1)*3 +2]
);
tri2Edge.Set(
vertexData[nlv*3 ] - vertexData[(nlv-1)*3 ],
vertexData[nlv*3 +1] - vertexData[(nlv-1)*3 +1],
vertexData[nlv*3 +2] - vertexData[(nlv-1)*3 +2]
);
triUpEdge.Set(
vertexData[nlv*3 ] - vertexData[(nlv+segmentsAround+1)*3 ],
vertexData[nlv*3 +1] - vertexData[(nlv+segmentsAround+1)*3 +1],
vertexData[nlv*3 +2] - vertexData[(nlv+segmentsAround+1)*3 +2]
);
triDownEdge.Set(
vertexData[(nlv-segmentsAround-1)*3 ] - vertexData[nlv*3 ],
vertexData[(nlv-segmentsAround-1)*3 +1] - vertexData[nlv*3 +1],
vertexData[(nlv-segmentsAround-1)*3 +2] - vertexData[nlv*3 +2]
);
/*normalData[nlv*3 + 0] = vertexData[nlv*3 +0] * 0.015f; //0.05f;
// these other 2 are actually in the correct direction since its a cylinder
normalData[nlv*3 + 1] = vertexData[nlv*3 + 1] * 0.015f;
normalData[nlv*3 + 2] = vertexData[nlv*3 + 2] * 0.015f;
continue;*/
}
MATHVECTOR <float, 3> faceNormal1 = triUpEdge.cross(tri1Edge);
MATHVECTOR <float, 3> faceNormal2 = tri2Edge.cross(triUpEdge);
MATHVECTOR <float, 3> faceNormal3 = triDownEdge.cross(tri1Edge);
MATHVECTOR <float, 3> faceNormal4 = tri2Edge.cross(triDownEdge);
MATHVECTOR <float, 3> vNormal = faceNormal1 + faceNormal2 + faceNormal3 + faceNormal4;
vNormal = vNormal.Normalize();
vNormal = vNormal * vertexNormalLength;
normalData[nlv*3 + 0] = vNormal[0];
normalData[nlv*3 + 1] = vNormal[1];
normalData[nlv*3 + 2] = vNormal[2];
}
/*else
{
normalData[nlv*3 + 0] = vertexData[nlv*3 +0] * 0.015f; //0.05f;
// these other 2 are actually in the correct direction since its a cylinder
normalData[nlv*3 + 1] = vertexData[nlv*3 + 1] * 0.015f;
normalData[nlv*3 + 2] = vertexData[nlv*3 + 2] * 0.015f;
}*/
}
//////////////////////////////////////////////
// VERTEXARRAY will copy this data
tire.SetVertices(&vertexData.front(), vertexFloatCount);
tire.SetFaces(&triData.front(), triVIndexCount);
tire.SetTexCoordSets(1);
tire.SetTexCoords(0, &texData.front(), texCoordFloats);
tire.SetNormals(&normalData.front(), vertexFloatCount);
//printf("tire created: v=%u, tri=%u\n", vertexCount, (triVIndexCount/3));
}
/////////////////////////////////////////////////////////////////////////////////////////////
// mg_wheelEdge
void mg_rim(VERTEXARRAY & rim, float sectionWidth_mm, float aspectRatio, float rimDiameter_in, float flangeDisplacement_mm)
{
int segmentsAround = 32;
float vertexNormalLength = 0.025f;
// some defaults that all get reset in the next decision
float innerRadius = 0.65f;
float flangeOuterRadius = 0.22f;
float flangeOutsideWidth = 0.17f;
float innerWidth = 0.16f; // the main part of the wheel
if (true)
{
innerRadius = rimDiameter_in * 0.0254f * 0.5f; // convert to a meter radius.
// fudge number: based on 15 inch rims on my car and truck - must be synchronized with the one in mg_tire
flangeOuterRadius = innerRadius * 1.08f;
innerRadius -= 0.010f; // knock off 10mm for the thickness of the sheet metal.
// calculate some messumenets of the tire
float sectionWidth_m = sectionWidth_mm / 1000.0f;
flangeOutsideWidth = sectionWidth_m - (sectionWidth_m / 4.0f); // subtract 1/8th from section width, to get the tread width (not really sure, looks ok though)
//flangeDisplacement_mm = abs(flangeDisplacement_mm); // make it so it can't spike outward
innerWidth = flangeOutsideWidth - (flangeDisplacement_mm/1000.0f * 2.0f);
}
// non-configurable parameters
int vertexRings = 6;
float angleIncrement = 360.0f / (float) segmentsAround;
/////////////////////////////////////
//
// vertices (temporary data)
//
int vertexesAround = segmentsAround + 1;
int vertexCount = vertexesAround * vertexRings;
int vertexFloatCount = vertexCount * 3; // * 3 cause there are 3 floats in a vertex
std::vector<float> vertexData;
vertexData.resize(vertexFloatCount);
// Right-side bevel, outer lip
for (int lv=0 ; lv<vertexesAround ; lv++)
{
vertexData[(lv+vertexesAround * 0) * 3 + 0] = 1.0f * (flangeOutsideWidth / 2.0f);
vertexData[(lv+vertexesAround * 0) * 3 + 1] = flangeOuterRadius * cosD(angleIncrement * lv);
vertexData[(lv+vertexesAround * 0) * 3 + 2] = flangeOuterRadius * sinD(angleIncrement * lv);
}
// Right-side bevel, inner lip
for (int lv=0 ; lv<vertexesAround ; lv++)
{
vertexData[(lv+vertexesAround * 1) * 3 + 0] = 1.0f * (innerWidth / 2.0f);
vertexData[(lv+vertexesAround * 1) * 3 + 1] = (innerRadius) * cosD(angleIncrement * lv);
vertexData[(lv+vertexesAround * 1) * 3 + 2] = (innerRadius) * sinD(angleIncrement * lv);
}
// Right-side of main cylinder
for (int lv=0 ; lv<vertexesAround ; lv++)
{
vertexData[(lv+vertexesAround * 2) * 3 + 0] = 1.0f * (innerWidth / 2.0f);
vertexData[(lv+vertexesAround * 2) * 3 + 1] = (innerRadius) * cosD(angleIncrement * lv);
vertexData[(lv+vertexesAround * 2) * 3 + 2] = (innerRadius) * sinD(angleIncrement * lv);
}
// Left-side of main cylinder,
for (int lv=0 ; lv<vertexesAround ; lv++)
{
vertexData[(lv+vertexesAround * 3) * 3 + 0] = -1.0f * (innerWidth / 2.0f);
vertexData[(lv+vertexesAround * 3) * 3 + 1] = (innerRadius) * cosD(angleIncrement * lv);
vertexData[(lv+vertexesAround * 3) * 3 + 2] = (innerRadius) * sinD(angleIncrement * lv);
}
// Left-side bevel, inner lip
for (int lv=0 ; lv<vertexesAround ; lv++)
{
vertexData[(lv+vertexesAround * 4) * 3 + 0] = -1.0f * (innerWidth / 2.0f);
vertexData[(lv+vertexesAround * 4) * 3 + 1] = innerRadius * cosD(angleIncrement * lv);
vertexData[(lv+vertexesAround * 4) * 3 + 2] = innerRadius * sinD(angleIncrement * lv);
}
// Left-side bevel, outer lip
for (int lv=0 ; lv<vertexesAround ; lv++)
{
vertexData[(lv+vertexesAround * 5) * 3 + 0] = -1.0f * (flangeOutsideWidth / 2.0f);
vertexData[(lv+vertexesAround * 5) * 3 + 1] = (flangeOuterRadius) * cosD(angleIncrement * lv);
vertexData[(lv+vertexesAround * 5) * 3 + 2] = (flangeOuterRadius) * sinD(angleIncrement * lv);
}
/////////////////////////////////////
//
// build triangles
// different from the last one
// 2 triangles * segmentsAround * 3 VertexIndexes * 3 completely separate tubes
int triVIndexCount = 2 * segmentsAround * 3 * 3;
std::vector<int> triData(triVIndexCount, 0);
//triData.resize(triVIndexCount);
int triIndex = 0;
for (int circleSegment=0 ; circleSegment<segmentsAround; circleSegment++)
{
// 1st triangle (Right-side - Inner to Sidewall)
triData[ (triIndex+0)*3 + 0 ] = circleSegment;
triData[ (triIndex+0)*3 + 1 ] = circleSegment+1;
triData[ (triIndex+0)*3 + 2 ] = circleSegment+vertexesAround;
// 2nd triangle
triData[ (triIndex+1)*3 + 0 ] = circleSegment+vertexesAround;
triData[ (triIndex+1)*3 + 1 ] = circleSegment+1;
triData[ (triIndex+1)*3 + 2 ] = circleSegment+vertexesAround+1;
triIndex +=2;
}
for (int circleSegment=0 ; circleSegment<segmentsAround; circleSegment++)
{
// 1st triangle (Right-side - Inner to Sidewall)
triData[ (triIndex+0)*3 + 0 ] = (2*vertexesAround)+circleSegment;
triData[ (triIndex+0)*3 + 1 ] = (2*vertexesAround)+circleSegment+1;
triData[ (triIndex+0)*3 + 2 ] = (2*vertexesAround)+circleSegment+vertexesAround;
// 2nd triangle
triData[ (triIndex+1)*3 + 0 ] = (2*vertexesAround)+circleSegment+vertexesAround;
triData[ (triIndex+1)*3 + 1 ] = (2*vertexesAround)+circleSegment+1;
triData[ (triIndex+1)*3 + 2 ] = (2*vertexesAround)+circleSegment+vertexesAround+1;
triIndex +=2;
}
for (int circleSegment=0 ; circleSegment<segmentsAround; circleSegment++)
{
// 1st triangle (Right-side - Inner to Sidewall)
triData[ (triIndex+0)*3 + 0 ] = (4*vertexesAround)+circleSegment+0;
triData[ (triIndex+0)*3 + 1 ] = (4*vertexesAround)+circleSegment+1;
triData[ (triIndex+0)*3 + 2 ] = (4*vertexesAround)+circleSegment+vertexesAround;
// 2nd triangle
triData[ (triIndex+1)*3 + 0 ] = (4*vertexesAround)+circleSegment+vertexesAround;
triData[ (triIndex+1)*3 + 1 ] = (4*vertexesAround)+circleSegment+1;
triData[ (triIndex+1)*3 + 2 ] = (4*vertexesAround)+circleSegment+vertexesAround+1;
triIndex +=2;
}
//////////////////////////////////////////////
// Texture Coordinates
int texCoordFloats = vertexCount * 2;
std::vector<float> texData;
texData.resize(texCoordFloats);
// set them all to zero for the time being
for ( int tlv=0 ; tlv< vertexCount ; tlv++ )
{
float u = tlv % vertexesAround;
u = u / segmentsAround;
texData[ tlv * 2 ] = u;
float v = 0;
if ( tlv < vertexesAround*1 )
{
v = 1.0 - 0.0f;
}
else if ( tlv < vertexesAround*2 )
{
v = 1.0 - 0.125f;
}
else if ( tlv < vertexesAround*3 )
{
v = 1.0 - 0.125f;
}
else if ( tlv < vertexesAround*4 )
{
v = 1.0 - 0.25f;
}
else if ( tlv < vertexesAround*5 )
{
v = 1.0 - 0.125f;
}
else //if ( tlv < vertexesAround*6 )
{
v = 1.0 - 0.25f;
}
texData[ tlv * 2 + 1 ] = v;
}
///////////////////////////////////////////////////////
// time for normals
std::vector<float> normalData;
normalData.resize(vertexFloatCount);
MATHVECTOR <float, 3> tri1Edge; // one of the edges of a triangle that goes around the tire's circle
MATHVECTOR <float, 3> tri2Edge; // one of the edges of a triangle that goes around the tire's circle
MATHVECTOR <float, 3> triUpEdge;
for (int nlv=0 ; nlv<vertexCount ; nlv++)
{
normalData[nlv*3+0] = 0.1;
normalData[nlv*3+1] = 0;
normalData[nlv*3+2] = 0;
}
for (int nlv=0 ; nlv<vertexCount ; nlv++)
{
if ( nlv < vertexesAround*1 ) // first ring of vertexes
{
///////////////////////////////////////////////////
// first ring of vertexes
if ((nlv % vertexesAround) == 0 ) // first vertex
{
tri1Edge.Set(
vertexData[nlv*3 ] - vertexData[(nlv+1)*3 ],
vertexData[nlv*3 +1] - vertexData[(nlv+1)*3 +1],
vertexData[nlv*3 +2] - vertexData[(nlv+1)*3 +2]
);
tri2Edge.Set(