fix bad normal calculation

__init__.py

@@ -1,7 +1,7 @@
 bl_info = {
     "name": "gp interpolate",
     "author": "Christophe Seux, Samuel Bernou",
-    "version": (0, 7, 3),
+    "version": (0, 7, 4),
     "blender": (3, 6, 0),
     "location": "Sidebar > Gpencil Tab > Interpolate",
     "description": "Interpolate Grease pencil strokes over 3D",

interpolate_strokes/operators.py

@@ -3,7 +3,7 @@ import numpy as np
 from time import perf_counter, time, sleep
 from mathutils import Vector, Matrix
 
-from gp_interpolate.utils import (matrix_transform,
+from ..utils import (matrix_transform,
                                   plane_on_bone,
                                   ray_cast_point,
                                   obj_ray_cast,

utils.py

@@ -35,12 +35,30 @@ class attr_set():
 
 # --- Vector
 
-def triangle_normal(a, b, c):
+def triangle_normal(p1, p2, p3):
-    x = a[1] * b[2] - a[2] * b[1]
+    """
-    y = a[2] * b[0] - a[0] * b[2]
+    Calculate the normal of a triangle given its three vertices.
-    z = a[0] * b[1] - a[1] * b[0]
+
-    
+    Parameters:
-    return np.array([x, y, z], dtype='float64')
+    p1, p2, p3: the 3 vertices of the triangle
+
+    Returns:
+    mathutils.Vector: The normalized normal vector of the triangle.
+    """
+    ## Get edge vectors
+    edge1 = Vector(p2) - Vector(p1)
+    edge2 = Vector(p3) - Vector(p1)
+    ## Get normal (Cross product of the edge vectors)
+    normal = edge1.cross(edge2)
+    normal.normalize()
+    return normal
+
+## Bad normal calculation !!
+# def triangle_normal(a, b, c):
+#     x = a[1] * b[2] - a[2] * b[1]
+#     y = a[2] * b[0] - a[0] * b[2]
+#     z = a[0] * b[1] - a[1] * b[0]
+#     return np.array([x, y, z], dtype='float64')
 
 def plane_coords(size=1):
     v = size * 0.5
@@ -84,6 +102,20 @@ def get_tri_from_face(hit_location, face_index, object_hit, depsgraph):
     return tri, tri_indices
 
 def ray_cast_point(point, origin, depsgraph):
+    '''Return object hit by ray cast, hit location and triangle vertices coordinates and indices
+
+    point: point coordinate in world space
+    origin: origin of the ray in world space
+    depsgraph: current depsgraph (use bpy.context.evaluated_depsgraph_get())
+
+    return:
+        object_hit (object): Object that was hit
+        hit_location (Vector3, as np.array): Location Vector of the hit
+        tri (list(Vector)): List of Vector3 world space coordinate of hitten triangle (tesselated from face if needed)
+        tri_indices (list(int)): List of vertices index corresponding to tri coordinates
+
+    if nothing hit. return None, None, None, None 
+    '''
     ray = (point - origin)
     hit, hit_location, normal, face_index, object_hit, matrix = bpy.context.scene.ray_cast(depsgraph, origin, ray)
     
@@ -479,4 +511,25 @@ def index_list_from_bools(bool_list) -> list:
 ## -- animation
 
 def is_animated(obj):
-    return True
+    return True
+
+
+## -- regions operations
+
+def location_to_region(worldcoords) -> Vector:
+    '''Get a world 3d coordinate and return 2d region coordinate
+    
+    return: 2d vector in region space
+    '''
+    from bpy_extras import view3d_utils
+    return view3d_utils.location_3d_to_region_2d(bpy.context.region, bpy.context.space_data.region_3d, worldcoords)
+
+def region_to_location(viewcoords, depthcoords) -> Vector:
+    '''Get 3d world coordinate from viewport region 2d coordianate
+    viewcoords (Vector2): 2d region vector coordinate
+    depthcoords (Vector3): 3d coordinate to define the depth
+
+    return: Vector3 of the placed location
+    '''
+    from bpy_extras import view3d_utils
+    return view3d_utils.region_2d_to_location_3d(bpy.context.region, bpy.context.space_data.region_3d, viewcoords, depthcoords)