calculate polygon normal, tangent, and bitangent,

next step, use them for calculation
This commit is contained in:
Anakin 2017-02-05 16:39:37 +01:00
parent 4c40d140a9
commit cdf19911f6
2 changed files with 187 additions and 6 deletions

View File

@ -18,6 +18,9 @@ struct VertexData
QVector3D position;
QVector2D texCoord;
QVector3D vertexNormal;
QVector3D polygonNormal;
QVector3D tangent;
QVector3D bitangent;
};
struct Segment {

View File

@ -572,18 +572,106 @@ void MshFile::analyseSegmChunks(Model * dataDestination, QList<ChunkHeader*>& ch
if (tmp_buffer.size() == 5)
{
for (size_t i = 0; i < 3; i++)
new_segment->indices.push_back(tmp_buffer.takeFirst());
// calculate poylgon normal, tangent and bitangent
QVector3D vec1, vec2, norm, tan, bi;
QVector2D uv1, uv2;
float f;
vec1 = new_segment->vertices[tmp_buffer[0]].position - new_segment->vertices[tmp_buffer[1]].position;
vec2 = new_segment->vertices[tmp_buffer[0]].position - new_segment->vertices[tmp_buffer[2]].position;
uv1 = new_segment->vertices[tmp_buffer[0]].texCoord - new_segment->vertices[tmp_buffer[1]].texCoord;
uv2 = new_segment->vertices[tmp_buffer[0]].texCoord - new_segment->vertices[tmp_buffer[2]].texCoord;
f = 1.0f / (uv1.x() * uv2.y() - uv2.x() * uv1.y());
norm = QVector3D::crossProduct(vec1, vec2).normalized();
tan.setX(f * (uv2.y() * vec1.x() - uv1.y() * vec2.x()));
tan.setY(f * (uv2.y() * vec1.y() - uv1.y() * vec2.y()));
tan.setZ(f * (uv2.y() * vec1.z() - uv1.y() * vec2.z()));
tan.normalize();
bi.setX(f * (-uv2.x() * vec1.x() + uv1.x() * vec2.x()));
bi.setY(f * (-uv2.x() * vec1.y() + uv1.x() * vec2.y()));
bi.setZ(f * (-uv2.x() * vec1.z() + uv1.x() * vec2.z()));
bi.normalize();
for (int k = 0; k < 3; k++)
{
// polygon normal wasn't calculated before
if (new_segment->vertices[tmp_buffer[k]].polygonNormal == QVector3D(0, 0, 0))
{
new_segment->vertices[tmp_buffer[k]].polygonNormal = norm;
new_segment->vertices[tmp_buffer[k]].tangent = tan;
new_segment->vertices[tmp_buffer[k]].bitangent = bi;
new_segment->indices.push_back(tmp_buffer[k]);
}
// polygon normal already calculated so duplicate the vertex
else
{
new_segment->vertices.push_back(new_segment->vertices[tmp_buffer[k]]);
new_segment->vertices.back().polygonNormal = norm;
new_segment->vertices.back().tangent = tan;
new_segment->vertices.back().bitangent = bi;
new_segment->indices.push_back(new_segment->vertices.size() - 1);
}
}
tmp_buffer.remove(0, 3);
}
else if (tmp_buffer.size() > 5)
{
unsigned int tmp_multiPolySize = tmp_buffer.size() - 2;
// calculate poylgon normal, tangent and bitangent
QVector3D vec1, vec2, norm, tan, bi;
QVector2D uv1, uv2;
float f;
vec1 = new_segment->vertices[tmp_buffer[0]].position - new_segment->vertices[tmp_buffer[1]].position;
vec2 = new_segment->vertices[tmp_buffer[0]].position - new_segment->vertices[tmp_buffer[2]].position;
uv1 = new_segment->vertices[tmp_buffer[0]].texCoord - new_segment->vertices[tmp_buffer[1]].texCoord;
uv2 = new_segment->vertices[tmp_buffer[0]].texCoord - new_segment->vertices[tmp_buffer[2]].texCoord;
f = 1.0f / (uv1.x() * uv2.y() - uv2.x() * uv1.y());
norm = QVector3D::crossProduct(vec1, vec2).normalized();
tan.setX(f * (uv2.y() * vec1.x() - uv1.y() * vec2.x()));
tan.setY(f * (uv2.y() * vec1.y() - uv1.y() * vec2.y()));
tan.setZ(f * (uv2.y() * vec1.z() - uv1.y() * vec2.z()));
tan.normalize();
bi.setX(f * (-uv2.x() * vec1.x() + uv1.x() * vec2.x()));
bi.setY(f * (-uv2.x() * vec1.y() + uv1.x() * vec2.y()));
bi.setZ(f * (-uv2.x() * vec1.z() + uv1.x() * vec2.z()));
bi.normalize();
// for every triangle of the multi polygon..
for (unsigned int tri = 0; tri < tmp_multiPolySize - 2; tri++)
{
// ..calculate the edge indices
for (int triEdge = 0; triEdge < 3; triEdge++)
new_segment->indices.push_back(tmp_buffer[(tri + triEdge - ((tri % 2) * (triEdge - 1) * 2))]);
{
int curIndi = tmp_buffer[(tri + triEdge - ((tri % 2) * (triEdge - 1) * 2))];
// polygon normal wasn't calculated before
if (new_segment->vertices[curIndi].polygonNormal == QVector3D(0, 0, 0))
{
new_segment->vertices[curIndi].polygonNormal = norm;
new_segment->vertices[curIndi].tangent = tan;
new_segment->vertices[curIndi].bitangent = bi;
new_segment->indices.push_back(curIndi);
}
// polygon normal already calculated so duplicate the vertex
else
{
new_segment->vertices.push_back(new_segment->vertices[curIndi]);
new_segment->vertices.back().polygonNormal = norm;
new_segment->vertices.back().tangent = tan;
new_segment->vertices.back().bitangent = bi;
new_segment->indices.push_back(new_segment->vertices.size() - 1);
}
}
}
tmp_buffer.remove(0, tmp_multiPolySize);
}
@ -594,17 +682,107 @@ void MshFile::analyseSegmChunks(Model * dataDestination, QList<ChunkHeader*>& ch
// save the last polygon (no 2 high bit followed)
if (tmp_buffer.size() == 3)
{
for (size_t i = 0; i < 3; i++)
new_segment->indices.push_back(tmp_buffer.takeFirst());
// calculate poylgon normal, tangent and bitangent
QVector3D vec1, vec2, norm, tan, bi;
QVector2D uv1, uv2;
float f;
vec1 = new_segment->vertices[tmp_buffer[0]].position - new_segment->vertices[tmp_buffer[1]].position;
vec2 = new_segment->vertices[tmp_buffer[0]].position - new_segment->vertices[tmp_buffer[2]].position;
uv1 = new_segment->vertices[tmp_buffer[0]].texCoord - new_segment->vertices[tmp_buffer[1]].texCoord;
uv2 = new_segment->vertices[tmp_buffer[0]].texCoord - new_segment->vertices[tmp_buffer[2]].texCoord;
f = 1.0f / (uv1.x() * uv2.y() - uv2.x() * uv1.y());
norm = QVector3D::crossProduct(vec1, vec2).normalized();
tan.setX(f * (uv2.y() * vec1.x() - uv1.y() * vec2.x()));
tan.setY(f * (uv2.y() * vec1.y() - uv1.y() * vec2.y()));
tan.setZ(f * (uv2.y() * vec1.z() - uv1.y() * vec2.z()));
tan.normalize();
bi.setX(f * (-uv2.x() * vec1.x() + uv1.x() * vec2.x()));
bi.setY(f * (-uv2.x() * vec1.y() + uv1.x() * vec2.y()));
bi.setZ(f * (-uv2.x() * vec1.z() + uv1.x() * vec2.z()));
bi.normalize();
for (int k = 0; k < 3; k++)
{
//TODO: buffer size == 1; k = 2;
// polygon normal wasn't calculated before
if (new_segment->vertices[tmp_buffer[k]].polygonNormal == QVector3D(0, 0, 0))
{
new_segment->vertices[tmp_buffer[k]].polygonNormal = norm;
new_segment->vertices[tmp_buffer[k]].tangent = tan;
new_segment->vertices[tmp_buffer[k]].bitangent = bi;
new_segment->indices.push_back(tmp_buffer[k]);
}
// polygon normal already calculated so duplicate the vertex
else
{
new_segment->vertices.push_back(new_segment->vertices[tmp_buffer[k]]);
new_segment->vertices.back().polygonNormal = norm;
new_segment->vertices.back().tangent = tan;
new_segment->vertices.back().bitangent = bi;
new_segment->indices.push_back(new_segment->vertices.size() - 1);
}
}
tmp_buffer.remove(0, 3);
}
else if (tmp_buffer.size() > 3)
{
unsigned int tmp_multiPolySize = tmp_buffer.size();
// calculate poylgon normal, tangent and bitangent
QVector3D vec1, vec2, norm, tan, bi;
QVector2D uv1, uv2;
float f;
vec1 = new_segment->vertices[tmp_buffer[0]].position - new_segment->vertices[tmp_buffer[1]].position;
vec2 = new_segment->vertices[tmp_buffer[0]].position - new_segment->vertices[tmp_buffer[2]].position;
uv1 = new_segment->vertices[tmp_buffer[0]].texCoord - new_segment->vertices[tmp_buffer[1]].texCoord;
uv2 = new_segment->vertices[tmp_buffer[0]].texCoord - new_segment->vertices[tmp_buffer[2]].texCoord;
f = 1.0f / (uv1.x() * uv2.y() - uv2.x() * uv1.y());
norm = QVector3D::crossProduct(vec1, vec2).normalized();
tan.setX(f * (uv2.y() * vec1.x() - uv1.y() * vec2.x()));
tan.setY(f * (uv2.y() * vec1.y() - uv1.y() * vec2.y()));
tan.setZ(f * (uv2.y() * vec1.z() - uv1.y() * vec2.z()));
tan.normalize();
bi.setX(f * (-uv2.x() * vec1.x() + uv1.x() * vec2.x()));
bi.setY(f * (-uv2.x() * vec1.y() + uv1.x() * vec2.y()));
bi.setZ(f * (-uv2.x() * vec1.z() + uv1.x() * vec2.z()));
bi.normalize();
// for every triangle of the multi polygon..
for (unsigned int tri = 0; tri < tmp_multiPolySize - 2; tri++)
{
// ..calculate the edge indices
for (int triEdge = 0; triEdge < 3; triEdge++)
new_segment->indices.push_back(tmp_buffer[(tri + triEdge - ((tri % 2) * (triEdge - 1) * 2))]);
{
int curIndi = tmp_buffer[(tri + triEdge - ((tri % 2) * (triEdge - 1) * 2))];
// polygon normal wasn't calculated before
if (new_segment->vertices[curIndi].polygonNormal == QVector3D(0, 0, 0))
{
new_segment->vertices[curIndi].polygonNormal = norm;
new_segment->vertices[curIndi].tangent = tan;
new_segment->vertices[curIndi].bitangent = bi;
new_segment->indices.push_back(curIndi);
}
// polygon normal already calculated so duplicate the vertex
else
{
new_segment->vertices.push_back(new_segment->vertices[curIndi]);
new_segment->vertices.back().polygonNormal = norm;
new_segment->vertices.back().tangent = tan;
new_segment->vertices.back().bitangent = bi;
new_segment->indices.push_back(new_segment->vertices.size() - 1);
}
}
}
}
}
}