celestia/src/tools/cmod/common/cmodops.cpp

1475 lines
42 KiB
C++

// cmodops.cpp
//
// Copyright (C) 2004-2010, Chris Laurel <claurel@gmail.com>
//
// This program 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 2
// of the License, or (at your option) any later version.
//
// Perform various adjustments to a Celestia mesh.
#include "cmodops.h"
#include <celmodel/modelfile.h>
#include <celmath/mathlib.h>
#include <Eigen/Core>
#include <algorithm>
#include <vector>
#ifdef TRISTRIP
#include <NvTriStrip.h>
#endif
using namespace cmod;
using namespace Eigen;
using namespace std;
class VertexComparator : public std::binary_function<Vertex, Vertex, bool>
{
public:
virtual bool compare(const Vertex& a, const Vertex& b) const = 0;
bool operator()(const Vertex& a, const Vertex& b) const
{
return compare(a, b);
}
};
class FullComparator : public VertexComparator
{
public:
FullComparator(int _vertexSize) :
vertexSize(_vertexSize)
{
}
bool compare(const Vertex& a, const Vertex& b) const override
{
const auto* s0 = reinterpret_cast<const char*>(a.attributes);
const auto* s1 = reinterpret_cast<const char*>(b.attributes);
for (int i = 0; i < vertexSize; i++)
{
if (s0[i] < s1[i])
return true;
if (s0[i] > s1[i])
return false;
}
return false;
}
private:
int vertexSize;
};
class PointOrderingPredicate : public VertexComparator
{
public:
PointOrderingPredicate() = default;
bool compare(const Vertex& a, const Vertex& b) const override
{
const Vector3f* p0 = reinterpret_cast<const Vector3f*>(a.attributes);
const Vector3f* p1 = reinterpret_cast<const Vector3f*>(b.attributes);
if (p0->x() < p1->x())
{
return true;
}
if (p0->x() > p1->x())
{
return false;
}
else
{
if (p0->y() < p1->y())
return true;
if (p0->y() > p1->y())
return false;
else
return p0->z() < p1->z();
}
}
private:
int ignore;
};
class PointTexCoordOrderingPredicate : public VertexComparator
{
public:
PointTexCoordOrderingPredicate(uint32_t _posOffset,
uint32_t _texCoordOffset,
bool _wrap) :
posOffset(_posOffset),
texCoordOffset(_texCoordOffset),
wrap(_wrap)
{
}
bool compare(const Vertex& a, const Vertex& b) const override
{
const auto* adata = reinterpret_cast<const char*>(a.attributes);
const auto* bdata = reinterpret_cast<const char*>(b.attributes);
const Vector3f* p0 = reinterpret_cast<const Vector3f*>(adata + posOffset);
const Vector3f* p1 = reinterpret_cast<const Vector3f*>(bdata + posOffset);
const Vector2f* tc0 = reinterpret_cast<const Vector2f*>(adata + texCoordOffset);
const Vector2f* tc1 = reinterpret_cast<const Vector2f*>(bdata + texCoordOffset);
if (p0->x() < p1->x())
{
return true;
}
if (p0->x() > p1->x())
{
return false;
}
else
{
if (p0->y() < p1->y())
{
return true;
}
if (p0->y() > p1->y())
{
return false;
}
else
{
if (p0->z() < p1->z())
{
return true;
}
if (p0->z() > p1->z())
{
return false;
}
else
{
if (tc0->x() < tc1->x())
return true;
if (tc0->x() > tc1->x())
return false;
else
return tc0->y() < tc1->y();
}
}
}
}
private:
uint32_t posOffset;
uint32_t texCoordOffset;
bool wrap;
};
bool approxEqual(float x, float y, float prec)
{
return abs(x - y) <= prec * min(abs(x), abs(y));
}
class PointEquivalencePredicate : public VertexComparator
{
public:
PointEquivalencePredicate(uint32_t _posOffset,
float _tolerance) :
posOffset(_posOffset),
tolerance(_tolerance)
{
}
bool compare(const Vertex& a, const Vertex& b) const override
{
const auto* adata = reinterpret_cast<const char*>(a.attributes);
const auto* bdata = reinterpret_cast<const char*>(b.attributes);
const Vector3f* p0 = reinterpret_cast<const Vector3f*>(adata + posOffset);
const Vector3f* p1 = reinterpret_cast<const Vector3f*>(bdata + posOffset);
return (approxEqual(p0->x(), p1->x(), tolerance) &&
approxEqual(p0->y(), p1->y(), tolerance) &&
approxEqual(p0->z(), p1->z(), tolerance));
}
private:
uint32_t posOffset;
float tolerance;
};
class PointTexCoordEquivalencePredicate : public VertexComparator
{
public:
PointTexCoordEquivalencePredicate(uint32_t _posOffset,
uint32_t _texCoordOffset,
bool _wrap,
float _tolerance) :
posOffset(_posOffset),
texCoordOffset(_texCoordOffset),
wrap(_wrap),
tolerance(_tolerance)
{
}
bool compare(const Vertex& a, const Vertex& b) const override
{
const auto* adata = reinterpret_cast<const char*>(a.attributes);
const auto* bdata = reinterpret_cast<const char*>(b.attributes);
const Vector3f* p0 = reinterpret_cast<const Vector3f*>(adata + posOffset);
const Vector3f* p1 = reinterpret_cast<const Vector3f*>(bdata + posOffset);
const Vector2f* tc0 = reinterpret_cast<const Vector2f*>(adata + texCoordOffset);
const Vector2f* tc1 = reinterpret_cast<const Vector2f*>(bdata + texCoordOffset);
return (approxEqual(p0->x(), p1->x(), tolerance) &&
approxEqual(p0->y(), p1->y(), tolerance) &&
approxEqual(p0->z(), p1->z(), tolerance) &&
approxEqual(tc0->x(), tc1->x(), tolerance) &&
approxEqual(tc0->y(), tc1->y(), tolerance));
}
private:
uint32_t posOffset;
uint32_t texCoordOffset;
bool wrap;
float tolerance;
};
bool equal(const Vertex& a, const Vertex& b, uint32_t vertexSize)
{
const auto* s0 = reinterpret_cast<const char*>(a.attributes);
const auto* s1 = reinterpret_cast<const char*>(b.attributes);
for (uint32_t i = 0; i < vertexSize; i++)
{
if (s0[i] != s1[i])
return false;
}
return true;
}
bool equalPoint(const Vertex& a, const Vertex& b)
{
const Vector3f* p0 = reinterpret_cast<const Vector3f*>(a.attributes);
const Vector3f* p1 = reinterpret_cast<const Vector3f*>(b.attributes);
return *p0 == *p1;
}
bool operator==(const Mesh::VertexAttribute& a,
const Mesh::VertexAttribute& b)
{
return (a.semantic == b.semantic &&
a.format == b.format &&
a.offset == b.offset);
}
bool operator<(const Mesh::VertexAttribute& a,
const Mesh::VertexAttribute& b)
{
if (a.semantic < b.semantic)
{
return true;
}
if (b.semantic < a.semantic)
{
return false;
}
else
{
if (a.format < b.format)
return true;
if (b.format < a.format)
return false;
else
return a.offset < b.offset;
}
}
bool operator==(const Mesh::VertexDescription& a,
const Mesh::VertexDescription& b)
{
if (a.stride != b.stride || a.nAttributes != b.nAttributes)
return false;
for (uint32_t i = 0; i < a.nAttributes; i++)
{
if (!(a.attributes[i] == b.attributes[i]))
return false;
}
return true;
}
bool operator<(const Mesh::VertexDescription& a,
const Mesh::VertexDescription& b)
{
if (a.stride < b.stride)
return true;
if (b.stride < a.stride)
return false;
if (a.nAttributes < b.nAttributes)
return true;
if (b.nAttributes < b.nAttributes)
return false;
for (uint32_t i = 0; i < a.nAttributes; i++)
{
if (a.attributes[i] < b.attributes[i])
return true;
else if (b.attributes[i] < a.attributes[i])
return false;
}
return false;
}
class MeshVertexDescComparator :
public std::binary_function<const Mesh*, const Mesh*, bool>
{
public:
MeshVertexDescComparator() = default;
bool operator()(const Mesh* a, const Mesh* b) const
{
return a->getVertexDescription() < b->getVertexDescription();
}
private:
int ignore;
};
bool
UniquifyVertices(Mesh& mesh)
{
uint32_t nVertices = mesh.getVertexCount();
const Mesh::VertexDescription& desc = mesh.getVertexDescription();
if (nVertices == 0)
return false;
const char* vertexData = reinterpret_cast<const char*>(mesh.getVertexData());
if (vertexData == nullptr)
return false;
// Initialize the array of vertices
vector<Vertex> vertices(nVertices);
uint32_t i;
for (i = 0; i < nVertices; i++)
{
vertices[i] = Vertex(i, vertexData + i * desc.stride);
}
// Sort the vertices so that identical ones will be ordered consecutively
sort(vertices.begin(), vertices.end(), FullComparator(desc.stride));
// Count the number of unique vertices
uint32_t uniqueVertexCount = 0;
for (i = 0; i < nVertices; i++)
{
if (i == 0 || !equal(vertices[i - 1], vertices[i], desc.stride))
uniqueVertexCount++;
}
// No work left to do if we couldn't eliminate any vertices
if (uniqueVertexCount == nVertices)
return true;
// Build the vertex map and the uniquified vertex data
vector<uint32_t> vertexMap(nVertices);
auto* newVertexData = new char[uniqueVertexCount * desc.stride];
const char* oldVertexData = reinterpret_cast<const char*>(mesh.getVertexData());
uint32_t j = 0;
for (i = 0; i < nVertices; i++)
{
if (i == 0 || !equal(vertices[i - 1], vertices[i], desc.stride))
{
if (i != 0)
j++;
assert(j < uniqueVertexCount);
memcpy(newVertexData + j * desc.stride,
oldVertexData + vertices[i].index * desc.stride,
desc.stride);
}
vertexMap[vertices[i].index] = j;
}
// Replace the vertex data with the compacted data
mesh.setVertices(uniqueVertexCount, newVertexData);
mesh.remapIndices(vertexMap);
return true;
}
Vector3f
getVertex(const void* vertexData,
int positionOffset,
uint32_t stride,
uint32_t index)
{
const float* fdata = reinterpret_cast<const float*>(reinterpret_cast<const char*>(vertexData) + stride * index + positionOffset);
return Vector3f(fdata[0], fdata[1], fdata[2]);
}
Vector2f
getTexCoord(const void* vertexData,
int texCoordOffset,
uint32_t stride,
uint32_t index)
{
const float* fdata = reinterpret_cast<const float*>(reinterpret_cast<const char*>(vertexData) + stride * index + texCoordOffset);
return Vector2f(fdata[0], fdata[1]);
}
Vector3f
averageFaceVectors(const vector<Face>& faces,
uint32_t thisFace,
uint32*_t vertexFaces,
uint32_t vertexFaceCount,
float cosSmoothingAngle)
{
const Face& face = faces[thisFace];
Vector3f v = Vector3f(0, 0, 0);
for (uint32_t i = 0; i < vertexFaceCount; i++)
{
uint32_t f = vertexFaces[i];
float cosAngle = face.normal.dot(faces[f].normal);
if (f == thisFace || cosAngle > cosSmoothingAngle)
v += faces[f].normal;
}
if (v.squaredNorm() == 0.0f)
v = Vector3f(1.0f, 0.0f, 0.0f);
else
v.normalize();
return v;
}
void
copyVertex(void* newVertexData,
const Mesh::VertexDescription& newDesc,
const void* oldVertexData,
const Mesh::VertexDescription& oldDesc,
uint32_t oldIndex,
const uint32_t fromOffsets[])
{
const char* oldVertex = reinterpret_cast<const char*>(oldVertexData) +
oldDesc.stride * oldIndex;
auto* newVertex = reinterpret_cast<char*>(newVertexData);
for (uint32_t i = 0; i < newDesc.nAttributes; i++)
{
if (fromOffsets[i] != ~0u)
{
memcpy(newVertex + newDesc.attributes[i].offset,
oldVertex + fromOffsets[i],
Mesh::getVertexAttributeSize(newDesc.attributes[i].format));
}
}
}
void
augmentVertexDescription(Mesh::VertexDescription& desc,
Mesh::VertexAttributeSemantic semantic,
Mesh::VertexAttributeFormat format)
{
Mesh::VertexAttribute* attributes = new Mesh::VertexAttribute[desc.nAttributes + 1];
uint32_t stride = 0;
uint32_t nAttributes = 0;
bool foundMatch = false;
for (uint32_t i = 0; i < desc.nAttributes; i++)
{
if (semantic == desc.attributes[i].semantic &&
format != desc.attributes[i].format)
{
// The semantic matches, but the format does not; skip this
// item.
}
else
{
if (semantic == desc.attributes[i].semantic)
foundMatch = true;
attributes[nAttributes] = desc.attributes[i];
attributes[nAttributes].offset = stride;
stride += Mesh::getVertexAttributeSize(desc.attributes[i].format);
nAttributes++;
}
}
if (!foundMatch)
{
attributes[nAttributes++] = Mesh::VertexAttribute(semantic,
format,
stride);
stride += Mesh::getVertexAttributeSize(format);
}
delete[] desc.attributes;
desc.attributes = attributes;
desc.nAttributes = nAttributes;
desc.stride = stride;
}
/** Generate surface normals for a mesh. A new mesh with normals is returned, and
* the original mesh is unmodified.
*
* @param mesh the mesh to generate normals for
* @param smoothAngle maximum angle (in radians) between two faces that are
* treated as belonging to the same smooth surface patch
* @param weld true if vertices with identical positions should be treated
* as the same during normal generation (typically should be true)
* @param weldTolerance maximum difference between positions that should be
* considered identical during the weld step.
*/
cmod::Mesh*
GenerateNormals(const cmod::Mesh& mesh, float smoothAngle, bool weld, float weldTolerance)
{
uint32_t nVertices = mesh.getVertexCount();
float cosSmoothAngle = (float) cos(smoothAngle);
const Mesh::VertexDescription& desc = mesh.getVertexDescription();
if (desc.getAttribute(Mesh::Position).format != Mesh::Float3)
{
cerr << "Vertex position must be a float3\n";
return nullptr;
}
uint32_t posOffset = desc.getAttribute(Mesh::Position).offset;
uint32_t nFaces = 0;
uint32_t i;
for (i = 0; mesh.getGroup(i) != nullptr; i++)
{
const Mesh::PrimitiveGroup* group = mesh.getGroup(i);
switch (group->prim)
{
case Mesh::TriList:
if (group->nIndices < 3 || group->nIndices % 3 != 0)
{
cerr << "Triangle list has invalid number of indices\n";
return nullptr;
}
nFaces += group->nIndices / 3;
break;
case Mesh::TriStrip:
case Mesh::TriFan:
if (group->nIndices < 3)
{
cerr << "Error: tri strip or fan has less than three indices\n";
return nullptr;
}
nFaces += group->nIndices - 2;
break;
default:
cerr << "Cannot generate normals for non-triangle primitives\n";
return nullptr;
}
}
// Build the array of faces; this may require decomposing triangle strips
// and fans into triangle lists.
vector<Face> faces(nFaces);
uint32_t f = 0;
for (i = 0; mesh.getGroup(i) != nullptr; i++)
{
const Mesh::PrimitiveGroup* group = mesh.getGroup(i);
switch (group->prim)
{
case Mesh::TriList:
{
for (uint32_t j = 0; j < group->nIndices / 3; j++)
{
assert(f < nFaces);
faces[f].i[0] = group->indices[j * 3];
faces[f].i[1] = group->indices[j * 3 + 1];
faces[f].i[2] = group->indices[j * 3 + 2];
f++;
}
}
break;
case Mesh::TriStrip:
{
for (uint32_t j = 2; j < group->nIndices; j++)
{
assert(f < nFaces);
if (j % 2 == 0)
{
faces[f].i[0] = group->indices[j - 2];
faces[f].i[1] = group->indices[j - 1];
faces[f].i[2] = group->indices[j];
}
else
{
faces[f].i[0] = group->indices[j - 1];
faces[f].i[1] = group->indices[j - 2];
faces[f].i[2] = group->indices[j];
}
f++;
}
}
break;
case Mesh::TriFan:
{
for (uint32_t j = 2; j < group->nIndices; j++)
{
assert(f < nFaces);
faces[f].i[0] = group->indices[0];
faces[f].i[1] = group->indices[j - 1];
faces[f].i[2] = group->indices[j];
f++;
}
}
break;
default:
assert(0);
break;
}
}
assert(f == nFaces);
const void* vertexData = mesh.getVertexData();
// Compute normals for the faces
for (f = 0; f < nFaces; f++)
{
Face& face = faces[f];
Vector3f p0 = getVertex(vertexData, posOffset, desc.stride, face.i[0]);
Vector3f p1 = getVertex(vertexData, posOffset, desc.stride, face.i[1]);
Vector3f p2 = getVertex(vertexData, posOffset, desc.stride, face.i[2]);
face.normal = (p1 - p0).cross(p2 - p1);
if (face.normal.squaredNorm() > 0.0f)
{
face.normal.normalize();
}
}
// For each vertex, create a list of faces that contain it
uint32*_t faceCounts = new uint32[nVertices];_t
uint32**_t vertexFaces = new uint32*[nVertices];_t
// Initialize the lists
for (i = 0; i < nVertices; i++)
{
faceCounts[i] = 0;
vertexFaces[i] = nullptr;
}
// If we're welding vertices before generating normals, find identical
// points and merge them. Otherwise, the point indices will be the same
// as the attribute indices.
if (weld)
{
JoinVertices(faces, vertexData, desc,
PointOrderingPredicate(),
PointEquivalencePredicate(0, weldTolerance));
}
else
{
for (f = 0; f < nFaces; f++)
{
faces[f].vi[0] = faces[f].i[0];
faces[f].vi[1] = faces[f].i[1];
faces[f].vi[2] = faces[f].i[2];
}
}
// Count the number of faces in which each vertex appears
for (f = 0; f < nFaces; f++)
{
Face& face = faces[f];
faceCounts[face.vi[0]]++;
faceCounts[face.vi[1]]++;
faceCounts[face.vi[2]]++;
}
// Allocate space for the per-vertex face lists
for (i = 0; i < nVertices; i++)
{
if (faceCounts[i] > 0)
{
vertexFaces[i] = new uint32[faceCounts[i]_t + 1];
vertexFaces[i][0] = faceCounts[i];
}
}
// Fill in the vertex/face lists
for (f = 0; f < nFaces; f++)
{
Face& face = faces[f];
vertexFaces[face.vi[0]][faceCounts[face.vi[0]]--] = f;
vertexFaces[face.vi[1]][faceCounts[face.vi[1]]--] = f;
vertexFaces[face.vi[2]][faceCounts[face.vi[2]]--] = f;
}
// Compute the vertex normals by averaging
vector<Vector3f> vertexNormals(nFaces * 3);
for (f = 0; f < nFaces; f++)
{
Face& face = faces[f];
for (uint32_t j = 0; j < 3; j++)
{
vertexNormals[f * 3 + j] =
averageFaceVectors(faces, f,
&vertexFaces[face.vi[j]][1],
vertexFaces[face.vi[j]][0],
cosSmoothAngle);
}
}
// Finally, create a new mesh with normals included
// Create the new vertex description
Mesh::VertexDescription newDesc(desc);
augmentVertexDescription(newDesc, Mesh::Normal, Mesh::Float3);
// We need to convert the copy the old vertex attributes to the new
// mesh. In order to do this, we need the old offset of each attribute
// in the new vertex description. The fromOffsets array will contain
// this mapping.
uint32_t normalOffset = 0;
uint32_t fromOffsets[16];
for (i = 0; i < newDesc.nAttributes; i++)
{
fromOffsets[i] = ~0;
if (newDesc.attributes[i].semantic == Mesh::Normal)
{
normalOffset = newDesc.attributes[i].offset;
}
else
{
for (uint32_t j = 0; j < desc.nAttributes; j++)
{
if (desc.attributes[j].semantic == newDesc.attributes[i].semantic)
{
assert(desc.attributes[j].format == newDesc.attributes[i].format);
fromOffsets[i] = desc.attributes[j].offset;
break;
}
}
}
}
// Copy the old vertex data along with the generated normals to the
// new vertex data buffer.
void* newVertexData = new char[newDesc.stride * nFaces * 3];
for (f = 0; f < nFaces; f++)
{
Face& face = faces[f];
for (uint32_t j = 0; j < 3; j++)
{
char* newVertex = reinterpret_cast<char*>(newVertexData) +
(f * 3 + j) * newDesc.stride;
copyVertex(newVertex, newDesc,
vertexData, desc,
face.i[j],
fromOffsets);
memcpy(newVertex + normalOffset, &vertexNormals[f * 3 + j],
Mesh::getVertexAttributeSize(Mesh::Float3));
}
}
// Create the Celestia mesh
Mesh* newMesh = new Mesh();
newMesh->setVertexDescription(newDesc);
newMesh->setVertices(nFaces * 3, newVertexData);
// Create a trivial index list
uint32*_t indices = new uint32[nFaces_t * 3];
for (i = 0; i < nFaces * 3; i++)
{
indices[i] = i;
}
uint32_t firstIndex = 0;
for (uint32_t groupIndex = 0; mesh.getGroup(groupIndex) != 0; ++groupIndex)
{
const Mesh::PrimitiveGroup* group = mesh.getGroup(groupIndex);
unsigned int faceCount = 0;
switch (group->prim)
{
case Mesh::TriList:
faceCount = group->nIndices / 3;
break;
case Mesh::TriStrip:
case Mesh::TriFan:
faceCount = group->nIndices - 2;
break;
default:
assert(0);
break;
}
newMesh->addGroup(Mesh::TriList, mesh.getGroup(groupIndex)->materialIndex, faceCount * 3, indices + firstIndex);
firstIndex += faceCount * 3;
}
// Clean up
delete[] faceCounts;
for (i = 0; i < nVertices; i++)
{
if (vertexFaces[i] != nullptr)
delete[] vertexFaces[i];
}
delete[] vertexFaces;
return newMesh;
}
Mesh*
GenerateTangents(const Mesh& mesh, bool weld)
{
uint32_t nVertices = mesh.getVertexCount();
// In order to generate tangents, we require positions, normals, and
// 2D texture coordinates in the vertex description.
const Mesh::VertexDescription& desc = mesh.getVertexDescription();
if (desc.getAttribute(Mesh::Position).format != Mesh::Float3)
{
cerr << "Vertex position must be a float3\n";
return nullptr;
}
if (desc.getAttribute(Mesh::Normal).format != Mesh::Float3)
{
cerr << "float3 format vertex normal required\n";
return nullptr;
}
if (desc.getAttribute(Mesh::Texture0).format == Mesh::InvalidFormat)
{
cerr << "Texture coordinates must be present in mesh to generate tangents\n";
return nullptr;
}
if (desc.getAttribute(Mesh::Texture0).format != Mesh::Float2)
{
cerr << "Texture coordinate must be a float2\n";
return nullptr;
}
// Count the number of faces in the mesh.
// (All geometry should already converted to triangle lists)
uint32_t i;
uint32_t nFaces = 0;
for (i = 0; mesh.getGroup(i) != nullptr; i++)
{
const Mesh::PrimitiveGroup* group = mesh.getGroup(i);
if (group->prim == Mesh::TriList)
{
assert(group->nIndices % 3 == 0);
nFaces += group->nIndices / 3;
}
else
{
cerr << "Mesh should contain just triangle lists\n";
return nullptr;
}
}
// Build the array of faces; this may require decomposing triangle strips
// and fans into triangle lists.
vector<Face> faces(nFaces);
uint32_t f = 0;
for (i = 0; mesh.getGroup(i) != nullptr; i++)
{
const Mesh::PrimitiveGroup* group = mesh.getGroup(i);
switch (group->prim)
{
case Mesh::TriList:
{
for (uint32_t j = 0; j < group->nIndices / 3; j++)
{
assert(f < nFaces);
faces[f].i[0] = group->indices[j * 3];
faces[f].i[1] = group->indices[j * 3 + 1];
faces[f].i[2] = group->indices[j * 3 + 2];
f++;
}
}
break;
default:
break;
}
}
uint32_t posOffset = desc.getAttribute(Mesh::Position).offset;
uint32_t texCoordOffset = desc.getAttribute(Mesh::Texture0).offset;
const void* vertexData = mesh.getVertexData();
// Compute tangents for faces
for (f = 0; f < nFaces; f++)
{
Face& face = faces[f];
Vector3f p0 = getVertex(vertexData, posOffset, desc.stride, face.i[0]);
Vector3f p1 = getVertex(vertexData, posOffset, desc.stride, face.i[1]);
Vector3f p2 = getVertex(vertexData, posOffset, desc.stride, face.i[2]);
Vector2f tc0 = getTexCoord(vertexData, texCoordOffset, desc.stride, face.i[0]);
Vector2f tc1 = getTexCoord(vertexData, texCoordOffset, desc.stride, face.i[1]);
Vector2f tc2 = getTexCoord(vertexData, texCoordOffset, desc.stride, face.i[2]);
float s1 = tc1.x() - tc0.x();
float s2 = tc2.x() - tc0.x();
float t1 = tc1.y() - tc0.y();
float t2 = tc2.y() - tc0.y();
float a = s1 * t2 - s2 * t1;
if (a != 0.0f)
face.normal = (t2 * (p1 - p0) - t1 * (p2 - p0)) * (1.0f / a);
else
face.normal = Vector3f(0.0f, 0.0f, 0.0f);
}
// For each vertex, create a list of faces that contain it
uint32*_t faceCounts = new uint32[nVertices];_t
uint32**_t vertexFaces = new uint32*[nVertices];_t
// Initialize the lists
for (i = 0; i < nVertices; i++)
{
faceCounts[i] = 0;
vertexFaces[i] = nullptr;
}
// If we're welding vertices before generating normals, find identical
// points and merge them. Otherwise, the point indices will be the same
// as the attribute indices.
if (weld)
{
JoinVertices(faces, vertexData, desc,
PointTexCoordOrderingPredicate(posOffset, texCoordOffset, true),
PointTexCoordEquivalencePredicate(posOffset, texCoordOffset, true, 1.0e-5f));
}
else
{
for (f = 0; f < nFaces; f++)
{
faces[f].vi[0] = faces[f].i[0];
faces[f].vi[1] = faces[f].i[1];
faces[f].vi[2] = faces[f].i[2];
}
}
// Count the number of faces in which each vertex appears
for (f = 0; f < nFaces; f++)
{
Face& face = faces[f];
faceCounts[face.vi[0]]++;
faceCounts[face.vi[1]]++;
faceCounts[face.vi[2]]++;
}
// Allocate space for the per-vertex face lists
for (i = 0; i < nVertices; i++)
{
if (faceCounts[i] > 0)
{
vertexFaces[i] = new uint32[faceCounts[i]_t + 1];
vertexFaces[i][0] = faceCounts[i];
}
}
// Fill in the vertex/face lists
for (f = 0; f < nFaces; f++)
{
Face& face = faces[f];
vertexFaces[face.vi[0]][faceCounts[face.vi[0]]--] = f;
vertexFaces[face.vi[1]][faceCounts[face.vi[1]]--] = f;
vertexFaces[face.vi[2]][faceCounts[face.vi[2]]--] = f;
}
// Compute the vertex tangents by averaging
vector<Vector3f> vertexTangents(nFaces * 3);
for (f = 0; f < nFaces; f++)
{
Face& face = faces[f];
for (uint32_t j = 0; j < 3; j++)
{
vertexTangents[f * 3 + j] =
averageFaceVectors(faces, f,
&vertexFaces[face.vi[j]][1],
vertexFaces[face.vi[j]][0],
0.0f);
}
}
// Create the new vertex description
Mesh::VertexDescription newDesc(desc);
augmentVertexDescription(newDesc, Mesh::Tangent, Mesh::Float3);
// We need to convert the copy the old vertex attributes to the new
// mesh. In order to do this, we need the old offset of each attribute
// in the new vertex description. The fromOffsets array will contain
// this mapping.
uint32_t tangentOffset = 0;
uint32_t fromOffsets[16];
for (i = 0; i < newDesc.nAttributes; i++)
{
fromOffsets[i] = ~0;
if (newDesc.attributes[i].semantic == Mesh::Tangent)
{
tangentOffset = newDesc.attributes[i].offset;
}
else
{
for (uint32_t j = 0; j < desc.nAttributes; j++)
{
if (desc.attributes[j].semantic == newDesc.attributes[i].semantic)
{
assert(desc.attributes[j].format == newDesc.attributes[i].format);
fromOffsets[i] = desc.attributes[j].offset;
break;
}
}
}
}
// Copy the old vertex data along with the generated tangents to the
// new vertex data buffer.
void* newVertexData = new char[newDesc.stride * nFaces * 3];
for (f = 0; f < nFaces; f++)
{
Face& face = faces[f];
for (uint32_t j = 0; j < 3; j++)
{
char* newVertex = reinterpret_cast<char*>(newVertexData) +
(f * 3 + j) * newDesc.stride;
copyVertex(newVertex, newDesc,
vertexData, desc,
face.i[j],
fromOffsets);
memcpy(newVertex + tangentOffset, &vertexTangents[f * 3 + j],
Mesh::getVertexAttributeSize(Mesh::Float3));
}
}
// Create the Celestia mesh
Mesh* newMesh = new Mesh();
newMesh->setVertexDescription(newDesc);
newMesh->setVertices(nFaces * 3, newVertexData);
// Create a trivial index list
uint32*_t indices = new uint32[nFaces_t * 3];
for (i = 0; i < nFaces * 3; i++)
indices[i] = i;
uint32_t firstIndex = 0;
for (uint32_t groupIndex = 0; mesh.getGroup(groupIndex) != 0; ++groupIndex)
{
const Mesh::PrimitiveGroup* group = mesh.getGroup(groupIndex);
unsigned int faceCount = 0;
switch (group->prim)
{
case Mesh::TriList:
faceCount = group->nIndices / 3;
break;
case Mesh::TriStrip:
case Mesh::TriFan:
faceCount = group->nIndices - 2;
break;
default:
assert(0);
break;
}
newMesh->addGroup(Mesh::TriList, mesh.getGroup(groupIndex)->materialIndex, faceCount * 3, indices + firstIndex);
firstIndex += faceCount * 3;
}
// Clean up
delete[] faceCounts;
for (i = 0; i < nVertices; i++)
{
if (vertexFaces[i] != nullptr)
delete[] vertexFaces[i];
}
delete[] vertexFaces;
return newMesh;
}
void
addGroupWithOffset(Mesh& mesh,
const Mesh::PrimitiveGroup& group,
uint32_t offset)
{
if (group.nIndices == 0)
return;
uint32*_t newIndices = new uint32[group.nIndices];_t
for (uint32_t i = 0; i < group.nIndices; i++)
newIndices[i] = group.indices[i] + offset;
mesh.addGroup(group.prim, group.materialIndex,
group.nIndices, newIndices);
}
// Merge all meshes that share the same vertex description
Model*
MergeModelMeshes(const Model& model)
{
vector<Mesh*> meshes;
for (uint32_t i = 0; model.getMesh(i) != nullptr; i++)
{
meshes.push_back(model.getMesh(i));
}
// Sort the meshes by vertex description
sort(meshes.begin(), meshes.end(), MeshVertexDescComparator());
Model* newModel = new Model();
// Copy materials into the new model
for (uint32_t i = 0; model.getMaterial(i) != nullptr; i++)
{
newModel->addMaterial(model.getMaterial(i));
}
uint32_t meshIndex = 0;
while (meshIndex < meshes.size())
{
const Mesh::VertexDescription& desc =
meshes[meshIndex]->getVertexDescription();
// Count the number of matching meshes
uint32_t nMatchingMeshes;
for (nMatchingMeshes = 1;
meshIndex + nMatchingMeshes < meshes.size();
nMatchingMeshes++)
{
if (!(meshes[meshIndex + nMatchingMeshes]->getVertexDescription() == desc))
{
break;
}
}
// Count the number of vertices in all matching meshes
uint32_t totalVertices = 0;
uint32_t j;
for (j = meshIndex; j < meshIndex + nMatchingMeshes; j++)
{
totalVertices += meshes[j]->getVertexCount();
}
char* vertexData = new char[totalVertices * desc.stride];
// Create the new empty mesh
Mesh* mergedMesh = new Mesh();
mergedMesh->setVertexDescription(desc);
mergedMesh->setVertices(totalVertices, vertexData);
// Copy the vertex data and reindex and add primitive groups
uint32_t vertexCount = 0;
for (j = meshIndex; j < meshIndex + nMatchingMeshes; j++)
{
const Mesh* mesh = meshes[j];
memcpy(vertexData + vertexCount * desc.stride,
mesh->getVertexData(),
mesh->getVertexCount() * desc.stride);
for (uint32_t k = 0; mesh->getGroup(k) != nullptr; k++)
{
addGroupWithOffset(*mergedMesh, *mesh->getGroup(k),
vertexCount);
}
vertexCount += mesh->getVertexCount();
}
assert(vertexCount == totalVertices);
newModel->addMesh(mergedMesh);
meshIndex += nMatchingMeshes;
}
return newModel;
}
static Material*
cloneMaterial(const Material* other)
{
Material* material = new Material();
material->diffuse = other->diffuse;
material->specular = other->specular;
material->emissive = other->emissive;
material->specularPower = other->specularPower;
material->opacity = other->opacity;
material->blend = other->blend;
for (int i = 0; i < Material::TextureSemanticMax; ++i)
{
if (other->maps[i])
{
material->maps[i] = new Material::DefaultTextureResource(other->maps[i]->source());
}
}
return material;
}
/*! Generate normals for an entire model. Return the new model, or null if
* normal generation failed due to an out of memory error.
*/
Model*
GenerateModelNormals(const Model& model, float smoothAngle, bool weldVertices, float weldTolerance)
{
Model* newModel = new Model();
// Copy materials
for (unsigned int i = 0; model.getMaterial(i) != nullptr; i++)
{
newModel->addMaterial(cloneMaterial(model.getMaterial(i)));
}
bool ok = true;
for (unsigned int i = 0; model.getMesh(i) != nullptr; i++)
{
Mesh* mesh = model.getMesh(i);
Mesh* newMesh = nullptr;
newMesh = GenerateNormals(*mesh, smoothAngle, weldVertices, weldTolerance);
if (newMesh == nullptr)
{
ok = false;
}
else
{
newModel->addMesh(newMesh);
}
}
if (!ok)
{
// If all of the meshes weren't processed due to an out of memory error,
// delete the new model and return nullptr rather than a partially processed
// model.
delete newModel;
newModel = nullptr;
}
return newModel;
}
#ifdef TRISTRIP
bool
convertToStrips(Mesh& mesh)
{
vector<Mesh::PrimitiveGroup*> groups;
// NvTriStrip library can only handle 16-bit indices
if (mesh.getVertexCount() >= 0x10000)
{
return true;
}
// Verify that the mesh contains just tri strips
uint32_t i;
for (i = 0; mesh.getGroup(i) != nullptr; i++)
{
if (mesh.getGroup(i)->prim != Mesh::TriList)
return true;
}
// Convert the existing groups to triangle strips
for (i = 0; mesh.getGroup(i) != nullptr; i++)
{
const Mesh::PrimitiveGroup* group = mesh.getGroup(i);
// Convert the vertex indices to shorts for the TriStrip library
unsigned short* indices = new unsigned short[group->nIndices];
uint32_t j;
for (j = 0; j < group->nIndices; j++)
{
indices[j] = (unsigned short) group->indices[j];
}
PrimitiveGroup* strips = nullptr;
unsigned short nGroups;
bool r = GenerateStrips(indices,
group->nIndices,
&strips,
&nGroups,
false);
if (!r || strips == nullptr)
{
cerr << "Generate tri strips failed\n";
return false;
}
// Call the tristrip library to convert the lists to strips. Then,
// convert from the NvTriStrip's primitive group structure to the
// CMOD one and add it to the collection that will be added once
// the mesh's original primitive groups are cleared.
for (j = 0; j < nGroups; j++)
{
Mesh::PrimitiveGroupType prim = Mesh::InvalidPrimitiveGroupType;
switch (strips[j].type)
{
case PT_LIST:
prim = Mesh::TriList;
break;
case PT_STRIP:
prim = Mesh::TriStrip;
break;
case PT_FAN:
prim = Mesh::TriFan;
break;
}
if (prim != Mesh::InvalidPrimitiveGroupType &&
strips[j].numIndices != 0)
{
Mesh::PrimitiveGroup* newGroup = new Mesh::PrimitiveGroup();
newGroup->prim = prim;
newGroup->materialIndex = group->materialIndex;
newGroup->nIndices = strips[j].numIndices;
newGroup->indices = new uint32[newGroup->nIndices];_t
for (uint32_t k = 0; k < newGroup->nIndices; k++)
newGroup->indices[k] = strips[j].indices[k];
groups.push_back(newGroup);
}
}
delete[] strips;
}
mesh.clearGroups();
// Add the stripified groups to the mesh
for (vector<Mesh::PrimitiveGroup*>::const_iterator iter = groups.begin();
iter != groups.end(); iter++)
{
mesh.addGroup(*iter);
}
return true;
}
#endif
#if 0
if (genNormals || genTangents)
{
Model* newModel = new Model();
uint32_t i;
// Copy materials
for (i = 0; model->getMaterial(i) != nullptr; i++)
{
newModel->addMaterial(model->getMaterial(i));
}
// Generate normals and/or tangents for each model in the mesh
for (i = 0; model->getMesh(i) != nullptr; i++)
{
Mesh* mesh = model->getMesh(i);
Mesh* newMesh = nullptr;
if (genNormals)
{
newMesh = generateNormals(*mesh,
degToRad(smoothAngle),
weldVertices);
if (newMesh == nullptr)
{
cerr << "Error generating normals!\n";
return 1;
}
// TODO: clean up old mesh
mesh = newMesh;
}
if (genTangents)
{
newMesh = generateTangents(*mesh, weldVertices);
if (newMesh == nullptr)
{
cerr << "Error generating tangents!\n";
return 1;
}
// TODO: clean up old mesh
mesh = newMesh;
}
newModel->addMesh(mesh);
}
// delete model;
model = newModel;
}
if (mergeMeshes)
{
model = mergeModelMeshes(*model);
}
if (uniquify)
{
for (uint32_t i = 0; model->getMesh(i) != nullptr; i++)
{
Mesh* mesh = model->getMesh(i);
uniquifyVertices(*mesh);
}
}
#ifdef TRISTRIP
if (stripify)
{
SetCacheSize(vertexCacheSize);
for (uint32_t i = 0; model->getMesh(i) != nullptr; i++)
{
Mesh* mesh = model->getMesh(i);
convertToStrips(*mesh);
}
}
#endif
#endif