void ZoaDebugFunctions::addQuadToMesh( ci::TriMesh& mesh, const ci::Vec3f& P0, const ci::Vec3f& P1, const ci::Vec3f& P2, const ci::Vec3f& P3, const ci::ColorA& color )
{
ci::Vec3f e0 = P2 - P0;
ci::Vec3f e1 = P2 - P1;
ci::Vec3f n = e0.cross(e1).normalized();
mesh.appendVertex( P0 );
mesh.appendColorRGBA( color );
mesh.appendNormal( n );
mesh.appendVertex( P1 );
mesh.appendColorRGBA( color );
mesh.appendNormal( n );
mesh.appendVertex( P2 );
mesh.appendColorRGBA( color );
mesh.appendNormal( n );
mesh.appendVertex( P3 );
mesh.appendColorRGBA( color );
mesh.appendNormal( n );
int vert0 = mesh.getNumVertices() - 4;
int vert1 = mesh.getNumVertices() - 1;
int vert2 = mesh.getNumVertices() - 2;
int vert3 = mesh.getNumVertices() - 3;
mesh.appendTriangle( vert0, vert3, vert1 );
mesh.appendTriangle( vert3, vert2, vert1 );
}
void ZoaDebugFunctions::calculateTriMeshNormals( ci::TriMesh &mesh )
{
const std::vector<ci::Vec3f>& vertices = mesh.getVertices();
const std::vector<uint32_t>& indices = mesh.getIndices();
// remove all current normals
std::vector<ci::Vec3f>& normals = mesh.getNormals();
normals.reserve( mesh.getNumVertices() );
normals.clear();
// set the normal for each vertex to (0, 0, 0)
for(size_t i=0; i < mesh.getNumVertices(); ++i)
normals.push_back( ci::Vec3f::zero() );
// Average out the normal for each vertex at an index
for(size_t i=0; i< mesh.getNumTriangles(); ++i)
{
ci::Vec3f v0 = vertices[ indices[i * 3] ];
ci::Vec3f v1 = vertices[ indices[i * 3 + 1] ];
ci::Vec3f v2 = vertices[ indices[i * 3 + 2] ];
// calculate normal and normalize it, so each of the normals equally contributes to the final result
ci::Vec3f e0 = v2 - v0;
ci::Vec3f e1 = v2 - v1;
ci::Vec3f n = e0.cross(e1).normalized();
// add the normal to the final result, so we get an average of the normals of each triangle
normals[ indices[i * 3] ] += n;
normals[ indices[i * 3 + 1] ] += n;
normals[ indices[i * 3 + 2] ] += n;
}
// the normals are probably not normalized by now, so make sure their lengths will be 1.0 as expected
for(size_t i=0;i< normals.size();++i) {
normals[i].normalize();
}
}
TriMesh MeshHelper::subdivide( const ci::TriMesh &triMesh, uint32_t division, bool normalize )
{
if ( division <= 1 || triMesh.getNumIndices() == 0 || triMesh.getNumVertices() == 0 ) {
return triMesh;
}
vector<uint32_t> indices = triMesh.getIndices();
vector<Vec3f> normals = triMesh.getNormals();
vector<Vec3f> positions = triMesh.getVertices();
vector<Vec2f> texCoords = triMesh.getTexCoords();
vector<uint32_t> indicesBuffer( indices );
indices.clear();
indices.reserve( indicesBuffer.size() * 4 );
uint32_t index0;
uint32_t index1;
uint32_t index2;
uint32_t index3;
uint32_t index4;
uint32_t index5;
for ( vector<uint32_t>::const_iterator iter = indicesBuffer.begin(); iter != indicesBuffer.end(); ) {
index0 = *iter;
++iter;
index1 = *iter;
++iter;
index2 = *iter;
++iter;
if ( normalize ) {
index3 = positions.size();
positions.push_back( positions.at( index0 ).lerp( 0.5f, positions.at( index1 ) ).normalized() * 0.5f );
index4 = positions.size();
positions.push_back( positions.at( index1 ).lerp( 0.5f, positions.at( index2 ) ).normalized() * 0.5f );
index5 = positions.size();
positions.push_back( positions.at( index2 ).lerp( 0.5f, positions.at( index0 ) ).normalized() * 0.5f );
} else {
index3 = positions.size();
positions.push_back( positions.at( index0 ).lerp( 0.5f, positions.at( index1 ) ) );
index4 = positions.size();
positions.push_back( positions.at( index1 ).lerp( 0.5f, positions.at( index2 ) ) );
index5 = positions.size();
positions.push_back( positions.at( index2 ).lerp( 0.5f, positions.at( index0 ) ) );
}
if ( !normals.empty() ) {
normals.push_back( normals.at( index0 ).lerp( 0.5f, normals.at( index1 ) ) );
normals.push_back( normals.at( index1 ).lerp( 0.5f, normals.at( index2 ) ) );
normals.push_back( normals.at( index2 ).lerp( 0.5f, normals.at( index0 ) ) );
}
if ( !texCoords.empty() ) {
texCoords.push_back( texCoords.at( index0 ).lerp( 0.5f, texCoords.at( index1 ) ) );
texCoords.push_back( texCoords.at( index1 ).lerp( 0.5f, texCoords.at( index2 ) ) );
texCoords.push_back( texCoords.at( index2 ).lerp( 0.5f, texCoords.at( index0 ) ) );
}
indices.push_back( index0 );
indices.push_back( index3 );
indices.push_back( index5 );
indices.push_back( index3 );
indices.push_back( index1 );
indices.push_back( index4 );
indices.push_back( index5 );
indices.push_back( index4 );
indices.push_back( index2 );
indices.push_back( index3 );
indices.push_back( index4 );
indices.push_back( index5 );
}
ci::TriMesh mesh = create( indices, positions, normals, texCoords );
indices.clear();
normals.clear();
positions.clear();
texCoords.clear();
return subdivide( mesh, division - 1, normalize );
}
void World::generateMesh(ci::TriMesh & mesh)
{
using namespace ci;
Vec3f offset = Vec3f(m_size * -0.5f, m_size * -0.5f, m_size * -0.5f);
for (size_t z = 0; z < m_size; ++z)
for (size_t y = 0; y < m_size; ++y)
for (size_t x = 0; x < m_size; ++x)
{
if (cell(x, y, z) == AIR)
{
for (size_t i = 0; i < 6; ++i)
{
int index = getNeigbour(x, y, z, i);
if (index != -1)
{
if (cell(index) == DIRT)
{
Vec3f normal = getNeigbourOffset(i);
Vec3f up = std::abs(normal.dot(Vec3f::yAxis())) > 0.9f ? Vec3f::zAxis() : Vec3f::yAxis();
Vec3f side = normal.cross(up) * 0.5f;
up = up * 0.5f;
Vec3f pos = offset + Vec3f(x, y, z) + (normal * 0.5f);
size_t indexStart = mesh.getNumVertices();
// Layout of the quad
//
// 0 --------------- 3
// | ^ up |
// | | |
// | side | |
// | <-----o pos |
// | |
// | |
// | |
// 1 --------------- 2
// Create the vertex data
mesh.appendVertex(pos + side + up);
mesh.appendVertex(pos + side - up);
mesh.appendVertex(pos - side - up);
mesh.appendVertex(pos - side + up);
mesh.appendNormal(-normal);
mesh.appendNormal(-normal);
mesh.appendNormal(-normal);
mesh.appendNormal(-normal);
// Create triangle data
mesh.appendTriangle(indexStart + 0, indexStart + 1, indexStart + 2);
mesh.appendTriangle(indexStart + 0, indexStart + 2, indexStart + 3);
}
}
}
}
}
}