#include "loader.h"
-#include "mesh.h"
Loader::Loader(QObject* parent, const QString& filename)
: QThread(parent), filename(filename)
{
+ // Nothing to do here
}
void Loader::run()
{
- QTime timer;
- timer.start();
- emit got_mesh(Mesh::load_stl(filename));
- qDebug() << "Time taken:" << timer.elapsed();
+ Mesh* mesh = load_stl();
+ if (mesh)
+ {
+ emit got_mesh(mesh);
+ emit loaded_file(filename);
+ }
+}
+
+
+////////////////////////////////////////////////////////////////////////////////
+
+struct Vec3
+{
+ GLfloat x, y, z;
+ bool operator!=(const Vec3& rhs) const
+ {
+ return x != rhs.x || y != rhs.y || z != rhs.z;
+ }
+ bool operator<(const Vec3& rhs) const
+ {
+ if (x != rhs.x) return x < rhs.x;
+ else if (y != rhs.y) return y < rhs.y;
+ else if (z != rhs.z) return z < rhs.z;
+ else return false;
+ }
+};
+
+typedef std::pair<Vec3, GLuint> Vec3i;
+
+////////////////////////////////////////////////////////////////////////////////
+
+Mesh* Loader::load_stl()
+{
+ QFile file(filename);
+ file.open(QIODevice::ReadOnly);
+ if (file.read(5) == "solid")
+ {
+ emit error_ascii_stl();
+ return NULL;
+ }
+ // Skip the rest of the header material
+ file.read(75);
+
+ QDataStream data(&file);
+ data.setByteOrder(QDataStream::LittleEndian);
+ data.setFloatingPointPrecision(QDataStream::SinglePrecision);
+
+ // Load the triangle count from the .stl file
+ uint32_t tri_count;
+ data >> tri_count;
+
+ // Verify that the file is the right size
+ if (file.size() != 84 + tri_count*50)
+ {
+ emit error_bad_stl();
+ return NULL;
+ }
- emit loaded_file(filename);
+ // Extract vertices into an array of xyz, unsigned pairs
+ QVector<Vec3i> verts(tri_count*3);
+
+ // Dummy array, because readRawData is faster than skipRawData
+ char buffer[sizeof(float)*3];
+
+ // Store vertices in the array, processing one triangle at a time.
+ for (auto v=verts.begin(); v != verts.end(); v += 3)
+ {
+ // Skip face's normal vector
+ data.readRawData(buffer, 3*sizeof(float));
+
+ // Load vertex data from .stl file into vertices
+ data >> v[0].first.x >> v[0].first.y >> v[0].first.z;
+ data >> v[1].first.x >> v[1].first.y >> v[1].first.z;
+ data >> v[2].first.x >> v[2].first.y >> v[2].first.z;
+
+ // Skip face attribute
+ data.readRawData(buffer, sizeof(uint16_t));
+ }
+
+ // Save indicies as the second element in the array
+ // (so that we can reconstruct triangle order after sorting)
+ for (size_t i=0; i < tri_count*3; ++i)
+ {
+ verts[i].second = i;
+ }
+
+ // Sort the set of vertices (to deduplicate)
+ std::sort(verts.begin(), verts.end());
+
+ // This vector will store triangles as sets of 3 indices
+ std::vector<GLuint> indices(tri_count*3);
+
+ // Go through the sorted vertex list, deduplicating and creating
+ // an indexed geometry representation for the triangles.
+ // Unique vertices are moved so that they occupy the first vertex_count
+ // positions in the verts array.
+ size_t vertex_count = 0;
+ for (auto v : verts)
+ {
+ if (!vertex_count || v.first != verts[vertex_count-1].first)
+ {
+ verts[vertex_count++] = v;
+ }
+ indices[v.second] = vertex_count - 1;
+ }
+ verts.resize(vertex_count);
+
+ std::vector<GLfloat> flat_verts;
+ flat_verts.reserve(vertex_count*3);
+ for (auto v : verts)
+ {
+ flat_verts.push_back(v.first.x);
+ flat_verts.push_back(v.first.y);
+ flat_verts.push_back(v.first.z);
+ }
+
+ return new Mesh(flat_verts, indices);
}
+