From 457a39c0939e9b195d5f7b48b56ed93e21217521 Mon Sep 17 00:00:00 2001
From: iperov <lepersorium@gmail.com>
Date: Sat, 10 Apr 2021 09:58:33 +0400
Subject: [PATCH] mathlib update

---
 core/mathlib/__init__.py | 74 +++++++++++++++++++++++++++++++++++++++-
 1 file changed, 73 insertions(+), 1 deletion(-)

diff --git a/core/mathlib/__init__.py b/core/mathlib/__init__.py
index a11e725..7e5fa13 100644
--- a/core/mathlib/__init__.py
+++ b/core/mathlib/__init__.py
@@ -1,7 +1,12 @@
-import numpy as np
 import math
+
+import cv2
+import numpy as np
+import numpy.linalg as npla
+
 from .umeyama import umeyama
 
+
 def get_power_of_two(x):
     i = 0
     while (1 << i) < x:
@@ -23,3 +28,70 @@ def rotationMatrixToEulerAngles(R) :
 
 def polygon_area(x,y):
     return 0.5*np.abs(np.dot(x,np.roll(y,1))-np.dot(y,np.roll(x,1)))
+
+def rotate_point(origin, point, deg):
+    """
+    Rotate a point counterclockwise by a given angle around a given origin.
+
+    The angle should be given in radians.
+    """
+    ox, oy = origin
+    px, py = point
+
+    rad = deg * math.pi / 180.0
+    qx = ox + math.cos(rad) * (px - ox) - math.sin(rad) * (py - oy)
+    qy = oy + math.sin(rad) * (px - ox) + math.cos(rad) * (py - oy)
+    return np.float32([qx, qy])
+    
+def transform_points(points, mat, invert=False):
+    if invert:
+        mat = cv2.invertAffineTransform (mat)
+    points = np.expand_dims(points, axis=1)
+    points = cv2.transform(points, mat, points.shape)
+    points = np.squeeze(points)
+    return points
+
+    
+def transform_mat(mat, res, tx, ty, rotation, scale):
+    """
+    transform mat in local space of res
+    scale -> translate -> rotate
+    
+        tx,ty       float
+        rotation    int degrees
+        scale       float
+    """
+    
+    
+    lt, rt, lb, ct = transform_points (  np.float32([(0,0),(res,0),(0,res),(res / 2, res/2) ]),mat, True)
+    
+    hor_v = (rt-lt).astype(np.float32)
+    hor_size = npla.norm(hor_v)
+    hor_v /= hor_size
+    
+    ver_v = (lb-lt).astype(np.float32)
+    ver_size = npla.norm(ver_v)
+    ver_v /= ver_size
+    
+    bt_diag_vec = (rt-ct).astype(np.float32)
+    half_diag_len = npla.norm(bt_diag_vec)
+    bt_diag_vec /= half_diag_len
+    
+    tb_diag_vec = np.float32( [ -bt_diag_vec[1], bt_diag_vec[0] ]  )
+
+    rt = ct + bt_diag_vec*half_diag_len*scale 
+    lb = ct - bt_diag_vec*half_diag_len*scale
+    lt = ct - tb_diag_vec*half_diag_len*scale
+    
+    rt[0] += tx*hor_size
+    lb[0] += tx*hor_size
+    lt[0] += tx*hor_size
+    rt[1] += ty*ver_size
+    lb[1] += ty*ver_size
+    lt[1] += ty*ver_size
+    
+    rt = rotate_point(ct, rt, rotation)
+    lb = rotate_point(ct, lb, rotation)
+    lt = rotate_point(ct, lt, rotation)
+    
+    return cv2.getAffineTransform( np.float32([lt, rt, lb]), np.float32([ [0,0], [res,0], [0,res] ]) )