Create vector3_for_2d_rendering.py

graphics/vector3_for_2d_rendering.py

@@ -0,0 +1,96 @@
+"""
+render 3d points for 2d surfaces.
+"""
+
+from __future__ import annotations
+import math
+
+__version__ = "2020.9.26"
+__author__ = "xcodz-dot, cclaus, dhruvmanila"
+
+
+def convert_to_2d(x: float, y: float, z: float, scale: float,
+                  distance: float) -> tuple[float, float]:
+    """
+    Converts 3d point to a 2d drawable point
+
+    >>> convert_to_2d(1.0, 2.0, 3.0, 10.0, 10.0)
+    (7.6923076923076925, 15.384615384615385)
+
+    >>> convert_to_2d(1, 2, 3, 10, 10)
+    (7.6923076923076925, 15.384615384615385)
+
+    >>> convert_to_2d("1", 2, 3, 10, 10)  # '1' is str
+    Traceback (most recent call last):
+        ...
+    TypeError: Input values must either be float or int: ['1', 2, 3, 10, 10]
+    """
+    if not all(isinstance(val, (float, int)) for val in locals().values()):
+        raise TypeError("Input values must either be float or int: "
+                        f"{list(locals().values())}")
+    projected_x = ((x * distance) / (z + distance)) * scale
+    projected_y = ((y * distance) / (z + distance)) * scale
+    return projected_x, projected_y
+
+
+def rotate(x: float, y: float, z: float, axis: str,
+           angle: float) -> tuple[float, float, float]:
+    """
+    rotate a point around a certain axis with a certain angle
+    angle can be any integer between 1, 360 and axis can be any one of
+    'x', 'y', 'z'
+
+    >>> rotate(1.0, 2.0, 3.0, 'y', 90.0)
+    (3.130524675073759, 2.0, 0.4470070007889556)
+
+    >>> rotate(1, 2, 3, "z", 180)
+    (0.999736015495891, -2.0001319704760485, 3)
+
+    >>> rotate('1', 2, 3, "z", 90.0)  # '1' is str
+    Traceback (most recent call last):
+        ...
+    TypeError: Input values except axis must either be float or int: ['1', 2, 3, 90.0]
+
+    >>> rotate(1, 2, 3, "n", 90)  # 'n' is not a valid axis
+    Traceback (most recent call last):
+        ...
+    ValueError: not a valid axis, choose one of 'x', 'y', 'z'
+
+    >>> rotate(1, 2, 3, "x", -90)
+    (1, -2.5049096187183877, -2.5933429780983657)
+
+    >>> rotate(1, 2, 3, "x", 450)  # 450 wrap around to 90
+    (1, 3.5776792428178217, -0.44744970165427644)
+    """
+    if not isinstance(axis, str):
+        raise TypeError("Axis must be a str")
+    input_variables = locals()
+    del input_variables["axis"]
+    if not all(isinstance(val, (float, int)) for val in input_variables.values()):
+        raise TypeError("Input values except axis must either be float or int: "
+                        f"{list(input_variables.values())}")
+    angle = (angle % 360) / 450 * 180 / math.pi
+    if axis == 'z':
+        new_x = x * math.cos(angle) - y * math.sin(angle)
+        new_y = y * math.cos(angle) + x * math.sin(angle)
+        new_z = z
+    elif axis == 'x':
+        new_y = y * math.cos(angle) - z * math.sin(angle)
+        new_z = z * math.cos(angle) + y * math.sin(angle)
+        new_x = x
+    elif axis == 'y':
+        new_x = x * math.cos(angle) - z * math.sin(angle)
+        new_z = z * math.cos(angle) + x * math.sin(angle)
+        new_y = y
+    else:
+        raise ValueError("not a valid axis, choose one of 'x', 'y', 'z'")
+
+    return new_x, new_y, new_z
+
+
+if __name__ == "__main__":
+    import doctest
+
+    doctest.testmod()
+    print(f"{convert_to_2d(1.0, 2.0, 3.0, 10.0, 10.0) = }")
+    print(f"{rotate(1.0, 2.0, 3.0, 'y', 90.0) = }")