Exposed simplify_mesh_lossless / tests required to see if advantages

pyfqmr/Simplify.pyx

@@ -17,18 +17,19 @@ class _hidden_ref(object):
         self.faces = None
         self.verts = None
 
-_REF = _hidden_ref() 
+_REF = _hidden_ref()
 
 cdef extern from "Simplify.h" namespace "Simplify" :
-    void simplify_mesh( int target_count, int update_rate, double aggressiveness, 
-                        bool verbose, int max_iterations,double alpha, int K, 
+    void simplify_mesh( int target_count, int update_rate, double aggressiveness,
+                        bool verbose, int max_iterations,double alpha, int K,
                         bool lossless, double threshold_lossless, bool preserve_border)
+    void simplify_mesh_lossless(bool verbose, double epsilon, int max_iterations)
     void setMeshFromExt(vector[vector[double]] vertices, vector[vector[int]] faces)
     vector[vector[int]] getFaces()
     vector[vector[double]] getVertices()
     vector[vector[double]] getNormals()
 
-cdef class Simplify : 
+cdef class Simplify :
 
     cdef int[:,:] faces_mv
     cdef double[:,:] vertices_mv
@@ -37,7 +38,7 @@ cdef class Simplify :
     cdef vector[vector[int]] triangles_cpp
     cdef vector[vector[double]] vertices_cpp
     cdef vector[vector[double]] normals_cpp
-    
+
     def __cinit__(self):
         pass
 
@@ -82,7 +83,7 @@ cdef class Simplify :
 
     cpdef void setMesh(self, vertices, faces, face_colors=None):
         """Method to set the mesh of the simplifier object.
-        
+
         Arguments
         ---------
         vertices : numpy.ndarray
@@ -93,7 +94,7 @@ cdef class Simplify :
             array of face_colors of shape (n_faces,3)
             this is not yet implemented
         """
-        _REF.faces = faces 
+        _REF.faces = faces
         _REF.verts = vertices
         # We have to clear the vectors to avoid overflow when using the simplify object
         # multiple times
@@ -107,9 +108,9 @@ cdef class Simplify :
         self.vertices_cpp = setVerticesNogil(self.vertices_mv, self.vertices_cpp)
         setMeshFromExt(self.vertices_cpp, self.triangles_cpp)
 
-    cpdef void simplify_mesh(self, int target_count = 100, int update_rate = 5, 
-        double aggressiveness=7., max_iterations = 100, bool verbose=True,  
-        bool lossless = False, double threshold_lossless=1e-3, double alpha = 1e-9, 
+    cpdef void simplify_mesh(self, int target_count = 100, int update_rate = 5,
+        double aggressiveness=7., max_iterations = 100, bool verbose=True,
+        bool lossless = False, double threshold_lossless=1e-3, double alpha = 1e-9,
         int K = 3, bool preserve_border = True):
         """Simplify mesh
 
@@ -118,23 +119,23 @@ cdef class Simplify :
             target_count : int
                 Target number of triangles, not used if lossless is True
             update_rate : int
-                Number of iterations between each update. 
+                Number of iterations between each update.
                 If lossless flag is set to True, rate is 1
             aggressiveness : float
-                Parameter controlling the growth rate of the threshold at each 
-                iteration when lossless is False. 
+                Parameter controlling the growth rate of the threshold at each
+                iteration when lossless is False.
             max_iterations : int
-                Maximal number of iterations 
+                Maximal number of iterations
             verbose : bool
                 control verbosity
             lossless : bool
-                Use the lossless simplification method 
+                Use the lossless simplification method
             threshold_lossless : float
-                Maximal error after which a vertex is not deleted, only for 
-                lossless method. 
-            alpha : float 
+                Maximal error after which a vertex is not deleted, only for
+                lossless method.
+            alpha : float
                 Parameter for controlling the threshold growth
-            K : int 
+            K : int
                 Parameter for controlling the thresold growth
             preserve_border : Bool
                 Flag for preserving vertices on open border
@@ -155,21 +156,52 @@ cdef class Simplify :
                 round(t_end-t_start,4), N_start, N_end)
             )
 
+    cpdef void simplify_mesh_lossless(self, bool verbose = True, double epsilon=1e-3, int max_iterations=9999):
+        """Simplify mesh using lossless method
+
+            Parameters
+            ----------
+            verbose : bool
+                Control verbosity
+            epsilon : float
+                Maximal error after which a vertex is not deleted, controlling the precision
+                of the lossless simplification.
+            max_iterations : int
+                Maximum number of iterations to perform the simplification.
+
+            Note
+            ----
+            This function simplifies the mesh while preserving vertex positions
+            within the specified error tolerance (`epsilon`). The process continues
+            until either the `max_iterations` is reached or no further simplifications
+            can be made within the specified tolerance.
+        """
+        N_start = self.faces_mv.shape[0]
+        t_start = _time()
+        simplify_mesh_lossless(verbose, epsilon, max_iterations)
+        t_end = _time()
+        N_end = getFaces().size()
+
+        if verbose:
+            print('simplified mesh in {} seconds from {} to {} triangles'.format(
+                round(t_end-t_start,4), N_start, N_end)
+            )
+
 @cython.boundscheck(False)
 @cython.wraparound(False)  # turn off negative index wrapping for entire function
 @cython.nonecheck(False)
 cdef vector[vector[double]] setVerticesNogil(double[:,:] vertices, vector[vector[double]] vector_vertices )nogil:
     """nogil function for filling the vector of vertices, "vector_vertices",
-    with the data found in the memory view of the array "vertices" 
+    with the data found in the memory view of the array "vertices"
     """
-    cdef vector[double] vertex 
+    cdef vector[double] vertex
     vector_vertices.reserve(vertices.shape[0])
 
     cdef size_t i = 0
     cdef size_t j = 0
     for i in range(vertices.shape[0]):
         vertex.clear()
-        for j in range(3):  
+        for j in range(3):
             vertex.push_back(vertices[i,j])
         vector_vertices.push_back(vertex)
     return vector_vertices
@@ -181,14 +213,14 @@ cdef vector[vector[int]] setFacesNogil(int[:,:] faces, vector[vector[int]] vecto
     """nogil function for filling the vector of faces, "vector_faces",
     with the data found in the memory view of the array "faces"
     """
-    cdef vector[int] triangle 
+    cdef vector[int] triangle
     vector_faces.reserve(faces.shape[0]);
 
     cdef size_t i = 0
     cdef size_t j = 0
     for i in range(faces.shape[0]):
         triangle.clear()
-        for j in range(3):  
+        for j in range(3):
             triangle.push_back(faces[i,j])
         vector_faces.push_back(triangle)
     return vector_faces
@@ -221,4 +253,4 @@ verts, faces = mesh.vertices, mesh.faces
 simpl.setMesh(verts, faces)
 simpl.getMesh()
 faces.shape
-"""
+"""