1 files changed, 137 insertions, 0 deletions
diff --git a/src/datavis3d/utils/vertexindexer.cpp b/src/datavis3d/utils/vertexindexer.cpp
new file mode 100644
index 00000000..c54cbf8a
--- /dev/null
+++ b/src/datavis3d/utils/vertexindexer.cpp
@@ -0,0 +1,137 @@
+#include "vertexindexer_p.h"
+
+#include <string.h> // for memcmp
+
+#include <QDebug>
+
+QTCOMMERCIALDATAVIS3D_BEGIN_NAMESPACE
+
+int unique_vertices = 0;
+
+// Returns true if v1 can be considered equal to v2
+bool VertexIndexer::is_near(float v1, float v2)
+{
+    return fabs(v1 - v2) < 0.01f;
+}
+
+// Searches through all already-exported vertices
+// for a similar one.
+// Similar = same position + same UVs + same normal
+bool VertexIndexer::getSimilarVertexIndex(QVector3D &in_vertex
+                                          , QVector2D &in_uv
+                                          , QVector3D &in_normal
+                                          , QVector<QVector3D> &out_vertices
+                                          , QVector<QVector2D> &out_uvs
+                                          , QVector<QVector3D> &out_normals
+                                          , unsigned short &result)
+{
+    // Lame linear search
+    for (int i = 0; i < out_vertices.size(); i++) {
+        if (is_near(in_vertex.x() , out_vertices[i].x())
+                && is_near(in_vertex.y() , out_vertices[i].y())
+                && is_near(in_vertex.z() , out_vertices[i].z())
+                && is_near(in_uv.x()     , out_uvs     [i].x())
+                && is_near(in_uv.y()     , out_uvs     [i].y())
+                && is_near(in_normal.x() , out_normals [i].x())
+                && is_near(in_normal.y() , out_normals [i].y())
+                && is_near(in_normal.z() , out_normals [i].z())) {
+            result = i;
+            return true;
+        }
+    }
+    // No other vertex could be used instead.
+    // Looks like we'll have to add it to the VBO.
+    return false;
+}
+
+bool VertexIndexer::getSimilarVertexIndex_fast(PackedVertex &packed
+                                               , QMap<PackedVertex, unsigned short> &VertexToOutIndex
+                                               , unsigned short &result)
+{
+    QMap<PackedVertex, unsigned short>::iterator it = VertexToOutIndex.find(packed);
+    if (it == VertexToOutIndex.end()) {
+        return false;
+    }
+    else {
+        result = it.value();
+        return true;
+    }
+}
+
+void VertexIndexer::indexVBO(QVector<QVector3D> &in_vertices
+                             , QVector<QVector2D> &in_uvs
+                             , QVector<QVector3D> &in_normals
+                             , QVector<unsigned short> &out_indices
+                             , QVector<QVector3D> &out_vertices
+                             , QVector<QVector2D> &out_uvs
+                             , QVector<QVector3D> &out_normals)
+{
+    unique_vertices = 0;
+    QMap<PackedVertex, unsigned short> VertexToOutIndex;
+
+    // For each input vertex
+    for (int i = 0; i < in_vertices.size(); i++) {
+        PackedVertex packed = {in_vertices[i], in_uvs[i], in_normals[i]};
+
+        // Try to find a similar vertex in out_XXXX
+        unsigned short index;
+        bool found = getSimilarVertexIndex_fast(packed, VertexToOutIndex, index);
+
+        if (found) { // A similar vertex is already in the VBO, use it instead !
+            out_indices.append(index);
+        }
+        else { // If not, it needs to be added in the output data.
+            unique_vertices++;
+            out_vertices.append(in_vertices[i]);
+            out_uvs.append(in_uvs[i]);
+            out_normals.append(in_normals[i]);
+            unsigned short newindex = (unsigned short)out_vertices.size() - 1;
+            out_indices.append(newindex);
+            VertexToOutIndex[packed] = newindex;
+        }
+    }
+    qDebug() << "unique vertices" << unique_vertices;
+}
+
+void VertexIndexer::indexVBO_TBN(QVector<QVector3D> &in_vertices
+                                 , QVector<QVector2D> &in_uvs
+                                 , QVector<QVector3D> &in_normals
+                                 , QVector<QVector3D> &in_tangents
+                                 , QVector<QVector3D> &in_bitangents
+                                 , QVector<unsigned short> &out_indices
+                                 , QVector<QVector3D> &out_vertices
+                                 , QVector<QVector2D> &out_uvs
+                                 , QVector<QVector3D> &out_normals
+                                 , QVector<QVector3D> &out_tangents
+                                 , QVector<QVector3D> &out_bitangents)
+{
+    unique_vertices = 0;
+    // For each input vertex
+    for (int i = 0; i < in_vertices.size(); i++) {
+
+        // Try to find a similar vertex in out_XXXX
+        unsigned short index;
+        bool found = getSimilarVertexIndex(in_vertices[i], in_uvs[i], in_normals[i]
+                                           , out_vertices, out_uvs, out_normals, index);
+
+        if (found) { // A similar vertex is already in the VBO, use it instead !
+            out_indices.append(index);
+
+            // Average the tangents and the bitangents
+            out_tangents[index] += in_tangents[i];
+            out_bitangents[index] += in_bitangents[i];
+        }
+        else { // If not, it needs to be added in the output data.
+            unique_vertices++;
+            out_vertices.append(in_vertices[i]);
+            out_uvs.append(in_uvs[i]);
+            out_normals.append(in_normals[i]);
+            out_tangents.append(in_tangents[i]);
+            out_bitangents.append(in_bitangents[i]);
+            out_indices.append((unsigned short)out_vertices.size() - 1);
+        }
+    }
+    qDebug() << "unique vertices" << unique_vertices;
+}
+
+QTCOMMERCIALDATAVIS3D_END_NAMESPACE