├── LICENSE
├── README.md
├── demo.py
├── ease.py
├── ease2.py
├── tests
    ├── test_ease.py
    └── test_ease2.py
└── tween.py


/LICENSE:
--------------------------------------------------------------------------------
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621 |                      END OF TERMS AND CONDITIONS
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623 |             How to Apply These Terms to Your New Programs
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667 | <https://www.gnu.org/licenses/>.
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669 |   The GNU General Public License does not permit incorporating your program
670 | into proprietary programs.  If your program is a subroutine library, you
671 | may consider it more useful to permit linking proprietary applications with
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673 | Public License instead of this License.  But first, please read
674 | <https://www.gnu.org/licenses/why-not-lgpl.html>.
675 | 


--------------------------------------------------------------------------------
/README.md:
--------------------------------------------------------------------------------
  1 | 
  2 | # Tweener
  3 | 
  4 | Helper functions for easing and tweening
  5 | 
  6 | 
  7 | ## Installation
  8 | 
  9 | ```
 10 |   pip install tweener
 11 | ```
 12 |     
 13 | ## Reference
 14 | 
 15 | #### Tween object
 16 | 
 17 | ```python
 18 | Tween(begin, end, duration, easing, easing_mode, boomerang, loop, reps)
 19 | ```
 20 | 
 21 | | Parameter | Type     | Description                                         |
 22 | | :-------- | :------- | :-------------------------------------------------- |
 23 | | `begin`   | `float`  | The beginning value of a property (default: `0.0`)  |
 24 | | `end`     | `float`  | The end value of a property (default: `1.0`)        |
 25 | | `duration`| `int`    | The length of time that an animation takes to complete (default: `600 ms`) |
 26 | | `easing`  | `Easing` | The type of easing to apply. (default: `Easing.LINEAR`) |
 27 | | `easing_mode` | `EasingMode` | The mode of easing `IN`, `OUT`, `IN_OUT`, (default: `IN`) |
 28 | | `boomerang` | `bool` | Returns the animation back to its starting point and vice versa. (default: `False`) |
 29 | | `loop`    | `bool`  | Loops the animation. When used with `boomerang`, it does the back and forth animation. (default: `False`) |
 30 | | `reps`  | `int` | Number of times the animation will be repeated. Zero means infinite. (default: `0`) |
 31 | 
 32 | #### Starts the animation
 33 | 
 34 | ```python
 35 | Tween().start()
 36 | ```
 37 | 
 38 | #### Updates the animation state
 39 | 
 40 | ```python
 41 | Tween().update()
 42 | ```
 43 | 
 44 | #### Pauses the animation
 45 | 
 46 | ```python
 47 | Tween().pause()
 48 | ```
 49 | 
 50 | #### Resumes the animation
 51 | 
 52 | ```python
 53 | Tween().resume()
 54 | ```
 55 | 
 56 | ### Easing types
 57 |     LINEAR
 58 |     SINE
 59 |     QUAD
 60 |     CUBIC
 61 |     QUART
 62 |     QUINT
 63 |     EXPO
 64 |     CIRC
 65 |     BACK
 66 |     ELASTIC
 67 |     BOUNCE
 68 | 
 69 | ### Easing modes (except linear)
 70 |     IN
 71 |     OUT
 72 |     IN_OUT
 73 | 
 74 | ## Example
 75 | I used Python version **3.10.5** and **pygame 2.1.2**
 76 | ```python
 77 | import pygame
 78 | from tweener import *
 79 | 
 80 | WIDTH = 600
 81 | HEIGHT = 600
 82 | TITLE = "Motion Demo"
 83 | FPS = 60
 84 | 
 85 | pygame.init()
 86 | canvas = pygame.display.set_mode((WIDTH, HEIGHT))
 87 | pygame.display.set_caption(TITLE)
 88 | 
 89 | running = True
 90 | clock = pygame.time.Clock()
 91 | 
 92 | rect = pg.Rect(0, 100, 100, 100)
 93 | anim_y = Tween(begin=0, 
 94 |                end=WIDTH-100,
 95 |                duration=1000,
 96 |                easing=Easing.BOUNCE,
 97 |                easing_mode=EasingMode.OUT,
 98 |                boomerang=True, 
 99 |                loop=True)
100 | 
101 | while running:
102 |     for event in pygame.event.get():
103 |         if event.type == pygame.QUIT:
104 |             running = False
105 |         elif event.type == pygame.KEYUP:
106 |             match event.key:
107 |                 case pygame.K_SPACE:
108 |                     anim_y.start()
109 |                 case pygame.K_p:
110 |                     anim_y.pause()
111 |                 case pygame.K_r:
112 |                     anim_y.resume()
113 | 
114 |     canvas.fill(pygame.Color(255, 255, 255))
115 | 
116 |     # Update
117 |     anim_y.update()
118 |     rect.x = anim_y.value
119 | 
120 |     # Render
121 |     pygame.draw.rect(canvas, (255, 0, 0), rect)
122 |     pygame.display.flip()
123 |     clock.tick(FPS)
124 | 
125 | pygame.quit()
126 | ```
127 | 
128 | 
129 | ## Demo
130 | https://user-images.githubusercontent.com/44640489/178249122-dbb962c0-eefd-4193-9fee-a001cf4e51a8.mp4
131 | ## Contributing
132 | 
133 | Contributions are always welcome!
134 | 
135 | ## References
136 | 
137 | - https://easings.net/
138 | - http://robertpenner.com/easing/
139 | 


--------------------------------------------------------------------------------
/demo.py:
--------------------------------------------------------------------------------
  1 | import pygame as pg
  2 | from tween import Tween, Easing, EasingMode
  3 | 
  4 | WIDTH = 600
  5 | HEIGHT = 600
  6 | TITLE = "Motion Demo"
  7 | FPS = 60
  8 | 
  9 | 
 10 | if __name__ == '__main__':
 11 |     pg.init()
 12 |     canvas = pg.display.set_mode((WIDTH, HEIGHT))
 13 |     pg.display.set_caption(TITLE)
 14 | 
 15 |     running = True
 16 |     clock = pg.time.Clock()
 17 | 
 18 |     base_canvas = pg.Surface((WIDTH, HEIGHT), pg.SRCALPHA)
 19 | 
 20 |     font = pg.font.SysFont('arialblack', 14)
 21 | 
 22 |     BOX_SIZE = 30
 23 |     SPACING = 20
 24 |     boxes = []
 25 |     easings = (
 26 |         Easing.LINEAR,
 27 |         Easing.SINE,
 28 |         Easing.QUAD,
 29 |         Easing.CUBIC,
 30 |         Easing.QUART,
 31 |         Easing.QUINT,
 32 |         Easing.EXPO,
 33 |         Easing.CIRC,
 34 |         Easing.BACK,
 35 |         Easing.ELASTIC,
 36 |         Easing.BOUNCE
 37 |     )
 38 |     ease_txt = (
 39 |         'linear',
 40 |         'sinusoidal',
 41 |         'quadratic',
 42 |         'cubic',
 43 |         'quartic',
 44 |         'quintic',
 45 |         'exponential',
 46 |         'circular',
 47 |         'back',
 48 |         'elastic',
 49 |         'bounce'
 50 |     )
 51 | 
 52 |     mode = font.render('Mode: IN', True, pg.Color(76, 58, 81))
 53 | 
 54 |     for i in range(11):
 55 |         boxes.append({
 56 |             'rect': pg.Rect(0, (BOX_SIZE + SPACING) * i, BOX_SIZE, BOX_SIZE),
 57 |             'tween': Tween(0, WIDTH - BOX_SIZE,
 58 |                            duration=2000,
 59 |                            easing=easings[i],
 60 |                            easing_mode=EasingMode.IN,
 61 |                            boomerang=True,
 62 |                            loop=True,
 63 |                            reps=0),
 64 |             'text': font.render(ease_txt[i], True, pg.Color(119, 67, 96))
 65 |         })
 66 | 
 67 |     # You can't use special functions in colors
 68 |     alpha_tween = Tween(255, 0,
 69 |                         duration=2000,
 70 |                         easing=Easing.QUAD,
 71 |                         easing_mode=EasingMode.IN_OUT,
 72 |                         boomerang=True,
 73 |                         loop=True,
 74 |                         reps=0)
 75 | 
 76 |     FPS = 60
 77 | 
 78 |     while running:
 79 |         for event in pg.event.get():
 80 |             if event.type == pg.QUIT:
 81 |                 running = False
 82 |             elif event.type == pg.KEYUP:
 83 |                 match event.key:
 84 |                     case pg.K_SPACE:
 85 |                         for box in boxes:
 86 |                             box['tween'].start()
 87 |                         alpha_tween.start()
 88 |                     case pg.K_p:
 89 |                         for box in boxes:
 90 |                             box['tween'].pause()
 91 |                         alpha_tween.pause()
 92 |                     case pg.K_r:
 93 |                         for box in boxes:
 94 |                             box['tween'].resume()
 95 |                         alpha_tween.resume()
 96 |                     case pg.K_1:
 97 |                         for box in boxes:
 98 |                             box['tween'].easing_mode = EasingMode.IN
 99 |                         mode = font.render('Mode: IN', True, pg.Color(119, 67, 96))
100 |                     case pg.K_2:
101 |                         for box in boxes:
102 |                             box['tween'].easing_mode = EasingMode.OUT
103 |                         mode = font.render('Mode: OUT', True, pg.Color(119, 67, 96))
104 |                     case pg.K_3:
105 |                         for box in boxes:
106 |                             box['tween'].easing_mode = EasingMode.IN_OUT
107 |                         mode = font.render('Mode: IN_OUT', True, pg.Color(119, 67, 96))
108 | 
109 | 
110 |         canvas.fill(pg.Color(255, 255, 255))
111 | 
112 |         # Update
113 |         step = font.render(f'Step: {boxes[0]["tween"].step:.3f}', True, pg.Color(76, 58, 81))
114 | 
115 |         for box in boxes:
116 |             box['tween'].update()
117 |             box['rect'].x = box['tween'].value
118 | 
119 |             # Render
120 |             canvas.blit(box['text'], (WIDTH / 2 - box['text'].get_width() / 2, box['rect'].y))
121 |             pg.draw.rect(canvas, pg.Color(76, 58, 81), box['rect'])
122 | 
123 |         canvas.blit(mode, (20, 540))
124 |         canvas.blit(step, (20, 560))
125 | 
126 |         pg.display.flip()
127 |         clock.tick(FPS)
128 | 
129 |     pg.quit()
130 | 


--------------------------------------------------------------------------------
/ease.py:
--------------------------------------------------------------------------------
  1 | import math
  2 | 
  3 | PI = math.pi
  4 | TAU = math.tau
  5 | FBE = 1.70158  # Fallback effect constant
  6 | 
  7 | 
  8 | class Ease:
  9 |     """
 10 |     Easing functions based on https://easings.net/
 11 |     
 12 |     * time_step - The current time/step of the animation. Domain: **[0.0-1.0]**
 13 |     **Returns** a value from range **[0.0-1.0]**
 14 |     """
 15 |     #############################################################
 16 |     # LINEAR
 17 |     #############################################################
 18 |     @staticmethod
 19 |     def linear(time_step: float) -> float:
 20 |         return time_step
 21 | 
 22 |     #############################################################
 23 |     # SINUSOIDAL
 24 |     #############################################################
 25 |     @staticmethod
 26 |     def in_sine(time_step: float) -> float:
 27 |         return time_step if time_step == 1.0 else 1 - math.cos((time_step * PI) / 2)
 28 | 
 29 |     @staticmethod
 30 |     def out_sine(time_step: float) -> float:
 31 |         return math.sin((time_step * PI) / 2)
 32 | 
 33 |     @staticmethod
 34 |     def in_out_sine(time_step: float) -> float:
 35 |         return -(math.cos(PI * time_step) - 1) / 2
 36 | 
 37 |     #############################################################
 38 |     # QUADRATIC
 39 |     #############################################################
 40 |     @staticmethod
 41 |     def in_quad(time_step: float) -> float:
 42 |         return math.pow(time_step, 2)
 43 | 
 44 |     @staticmethod
 45 |     def out_quad(time_step: float) -> float:
 46 |         return 1 - math.pow(1 - time_step, 2)
 47 | 
 48 |     @staticmethod
 49 |     def in_out_quad(time_step: float) -> float:
 50 |         return 2 * math.pow(time_step, 2) if time_step < 0.5 \
 51 |             else 1 - math.pow(-2 * time_step + 2, 2) / 2
 52 | 
 53 |     #############################################################
 54 |     # CUBIC
 55 |     #############################################################
 56 |     @staticmethod
 57 |     def in_cubic(time_step: float) -> float:
 58 |         return math.pow(time_step, 3)
 59 | 
 60 |     @staticmethod
 61 |     def out_cubic(time_step: float) -> float:
 62 |         return 1 - math.pow(1 - time_step, 3)
 63 | 
 64 |     @staticmethod
 65 |     def in_out_cubic(time_step: float) -> float:
 66 |         return 4 * math.pow(time_step, 3) if time_step < 0.5 \
 67 |             else 1 - math.pow(-2 * time_step + 2, 3) / 2
 68 | 
 69 |     #############################################################
 70 |     # QUARTIC
 71 |     #############################################################
 72 |     @staticmethod
 73 |     def in_quart(time_step: float) -> float:
 74 |         return math.pow(time_step, 4)
 75 | 
 76 |     @staticmethod
 77 |     def out_quart(time_step: float) -> float:
 78 |         return 1 - math.pow(1 - time_step, 4)
 79 | 
 80 |     @staticmethod
 81 |     def in_out_quart(time_step: float) -> float:
 82 |         return 8 * math.pow(time_step, 4) if time_step < 0.5 \
 83 |             else 1 - math.pow(-2 * time_step + 2, 4) / 2
 84 | 
 85 |     #############################################################
 86 |     # QUINTIC
 87 |     #############################################################
 88 |     @staticmethod
 89 |     def in_quint(time_step: float) -> float:
 90 |         return math.pow(time_step, 5)
 91 | 
 92 |     @staticmethod
 93 |     def out_quint(time_step: float) -> float:
 94 |         return 1 - math.pow(1 - time_step, 5)
 95 | 
 96 |     @staticmethod
 97 |     def in_out_quint(time_step: float) -> float:
 98 |         return 16 * math.pow(time_step, 5) if time_step < 0.5 \
 99 |             else 1 - math.pow(-2 * time_step + 2, 5) / 2
100 | 
101 |     #############################################################
102 |     # EXPONENTIAL
103 |     #############################################################
104 |     @staticmethod
105 |     def in_expo(time_step: float) -> float:
106 |         return time_step if time_step == 0.0 \
107 |             else math.pow(2, 10 * time_step - 10)
108 | 
109 |     @staticmethod
110 |     def out_expo(time_step: float) -> float:
111 |         return time_step if time_step == 1.0 \
112 |             else 1 - math.pow(2, -10 * time_step)
113 | 
114 |     @staticmethod
115 |     def in_out_expo(time_step: float) -> float:
116 |         if time_step == 0.0 or time_step == 1.0:
117 |             return time_step
118 |         elif time_step < 0.5:
119 |             return math.pow(2, 20 * time_step - 10) / 2
120 |         else:
121 |             return (2 - math.pow(2, -20 * time_step + 10)) / 2
122 | 
123 |     #############################################################
124 |     # CIRCULAR
125 |     #############################################################
126 |     @staticmethod
127 |     def in_circ(time_step: float) -> float:
128 |         return 1 - math.sqrt(1 - math.pow(time_step, 2))
129 | 
130 |     @staticmethod
131 |     def out_circ(time_step: float) -> float:
132 |         return math.sqrt(1 - math.pow(time_step - 1, 2))
133 | 
134 |     @staticmethod
135 |     def in_out_circ(time_step: float) -> float:
136 |         return (1 - math.sqrt(1 - pow(2 * time_step, 2))) / 2 if time_step < 0.5\
137 |             else (math.sqrt(1 - math.pow(-2 * time_step + 2, 2)) + 1) / 2
138 | 
139 |     #############################################################
140 |     # SPECIAL FUNCTIONS
141 |     #############################################################
142 |     @staticmethod
143 |     def in_back(time_step: float) -> float:
144 |         return time_step if time_step == 1.0 \
145 |             else (FBE + 1) * math.pow(time_step, 3) - FBE * math.pow(time_step, 2)
146 | 
147 |     @staticmethod
148 |     def out_back(time_step: float) -> float:
149 |         return time_step if time_step == 0.0 \
150 |             else 1 + (FBE + 1) * math.pow(time_step - 1, 3) + FBE * math.pow(time_step - 1, 2)
151 | 
152 |     @staticmethod
153 |     def in_out_back(time_step: float) -> float:
154 |         FBE2 = 2.5949095
155 |         return math.pow(2 * time_step, 2) * ((FBE2 + 1) * 2 * time_step - FBE2) / 2 if time_step < 0.5 \
156 |             else (math.pow(2 * time_step - 2, 2) * ((FBE2 + 1) * (time_step * 2 - 2) + FBE2) + 2) / 2
157 | 
158 |     @staticmethod
159 |     def in_elastic(time_step: float) -> float:
160 |         ANGLE = TAU / 3
161 |         return time_step if time_step == 0 or time_step == 1 \
162 |             else -math.pow(2, 10 * time_step - 10) * math.sin((time_step * 10 - 10.75) * ANGLE)
163 | 
164 |     @staticmethod
165 |     def out_elastic(time_step: float) -> float:
166 |         ANGLE = TAU / 3
167 |         return time_step if time_step == 0.0 or time_step == 1.0 \
168 |             else math.pow(2, -10 * time_step) * math.sin((time_step * 10 - 0.75) * ANGLE) + 1
169 | 
170 |     @staticmethod
171 |     def in_out_elastic(time_step: float) -> float:
172 |         ANGLE = TAU / 4.5
173 |         if time_step == 0.0 or time_step == 1.0:
174 |             return time_step
175 |         elif time_step < 0.5:
176 |             return -(math.pow(2, 20 * time_step - 10) * math.sin((20 * time_step - 11.125) * ANGLE)) / 2
177 |         else:
178 |             return math.pow(2, -20 * time_step + 10) * math.sin((20 * time_step - 11.125) * ANGLE) / 2 + 1
179 | 
180 |     @staticmethod
181 |     def in_bounce(time_step: float) -> float:
182 |         return 1 - Ease.out_bounce(1 - time_step)
183 | 
184 |     @staticmethod
185 |     def out_bounce(time_step: float) -> float:
186 |         if time_step < (1 / 2.75):
187 |             return 7.5625 * math.pow(time_step, 2)
188 |         elif time_step < (2 / 2.75):
189 |             return 7.5625 * math.pow(time_step - 1.5 / 2.75, 2) + .75
190 |         elif time_step < (2.5 / 2.75):
191 |             return 7.5625 * math.pow(time_step - 2.25 / 2.75, 2) + .9375
192 |         else:
193 |             return 7.5625 * math.pow(time_step - 2.625 / 2.75, 2) + .984375
194 | 
195 |     @staticmethod
196 |     def in_out_bounce(time_step: float) -> float:
197 |         return (1 - Ease.out_bounce(1 - 2 * time_step)) / 2 if time_step < 0.5 \
198 |             else (1 + Ease.out_bounce(2 * time_step - 1)) / 2
199 |     
200 | 


--------------------------------------------------------------------------------
/ease2.py:
--------------------------------------------------------------------------------
  1 | import math
  2 | from typing import Union, NewType
  3 | 
  4 | PI = math.pi
  5 | TAU = math.tau
  6 | 
  7 | 
  8 | class Ease2:
  9 |     """
 10 |     Easing equations by Robert Penner
 11 | 
 12 |     * step - The current time/step of the animation. Domain: **[0.0-1.0]**
 13 |     * start - the starting value of the property
 14 |     * delta - the amount of change between the start and end values, i.e. (end - start)
 15 |     * duration - the total the length of time that an animation takes to complete
 16 |     **Returns** a value from range **[0.0-1.0]**
 17 |     """
 18 |     Number = NewType('Number', Union[int, float])
 19 |     
 20 |     #############################################################
 21 |     # LINEAR
 22 |     #############################################################
 23 |     @staticmethod
 24 |     def linear(step: float, start: Number, delta: Number, duration: int) -> float:
 25 |         step = min(step / duration, 1.0)
 26 |         return delta * step + start
 27 | 
 28 |     #############################################################
 29 |     # SINUSOIDAL
 30 |     #############################################################
 31 |     @staticmethod
 32 |     def in_sine(step: float, start: Number, delta: Number, duration: int) -> float:
 33 |         step = min(step / duration, 1.0)
 34 |         if step == 1.0:
 35 |             return start + delta
 36 |         return delta * (1 - math.cos(step * (PI / 2))) + start
 37 | 
 38 |     @staticmethod
 39 |     def out_sine(step: float, start: Number, delta: Number, duration: int) -> float:
 40 |         step = min(step / duration, 1.0)
 41 |         return delta * math.sin(step * (PI / 2)) + start
 42 | 
 43 |     @staticmethod
 44 |     def in_out_sine(step: float, start: Number, delta: Number, duration: int) -> float:
 45 |         step = min(step / duration, 1.0)
 46 |         return delta / 2 * (1 - math.cos(PI * step)) + start
 47 | 
 48 |     #############################################################
 49 |     # QUADRATIC
 50 |     #############################################################
 51 |     @staticmethod
 52 |     def in_quad(step: float, start: Number, delta: Number, duration: int) -> float:
 53 |         step = min(step / duration, 1.0)
 54 |         return delta * math.pow(step, 2) + start
 55 | 
 56 |     @staticmethod
 57 |     def out_quad(step: float, start: Number, delta: Number, duration: int) -> float:
 58 |         step = min(step / duration, 1.0)
 59 |         return -delta * step * (step - 2) + start
 60 | 
 61 |     @staticmethod
 62 |     def in_out_quad(step: float, start: Number, delta: Number, duration: int) -> float:
 63 |         step /= duration / 2
 64 |         if step < 1:
 65 |             return delta / 2 * math.pow(step, 2) + start
 66 | 
 67 |         step = min(step - 1, 1.0)
 68 |         return -delta / 2 * (step * (step - 2) - 1) + start
 69 | 
 70 |     #############################################################
 71 |     # CUBIC
 72 |     #############################################################
 73 |     @staticmethod
 74 |     def in_cubic(step: float, start: Number, delta: Number, duration: int) -> float:
 75 |         step = min(step / duration, 1.0)
 76 |         return delta * math.pow(step, 3) + start
 77 | 
 78 |     @staticmethod
 79 |     def out_cubic(step: float, start: Number, delta: Number, duration: int) -> float:
 80 |         step = min(step / duration, 1.0)
 81 |         return delta * (math.pow(step - 1, 3) + 1) + start
 82 | 
 83 |     @staticmethod
 84 |     def in_out_cubic(step: float, start: Number, delta: Number, duration: int) -> float:
 85 |         step = min(step / (duration / 2), 2.0)
 86 |         if step < 1:
 87 |             return delta / 2 * math.pow(step, 3) + start
 88 | 
 89 |         return delta / 2 * (math.pow(step - 2, 3) + 2) + start
 90 | 
 91 |     #############################################################
 92 |     # QUARTIC
 93 |     #############################################################
 94 |     @staticmethod
 95 |     def in_quart(step: float, start: Number, delta: Number, duration: int) -> float:
 96 |         step = min(step / duration, 1.0)
 97 |         return delta * math.pow(step, 4) + start
 98 | 
 99 |     @staticmethod
100 |     def out_quart(step: float, start: Number, delta: Number, duration: int) -> float:
101 |         step = min(step / duration, 1.0)
102 |         return -delta * (math.pow(step - 1, 4) - 1) + start
103 | 
104 |     @staticmethod
105 |     def in_out_quart(step: float, start: Number, delta: Number, duration: int) -> float:
106 |         step = min(step / (duration / 2), 2.0)
107 |         if step < 1:
108 |             return delta / 2 * math.pow(step, 4) + start
109 | 
110 |         return -delta / 2 * (math.pow(step - 2, 4) - 2) + start
111 | 
112 |     #############################################################
113 |     # QUINTIC
114 |     #############################################################
115 |     @staticmethod
116 |     def in_quint(step: float, start: Number, delta: Number, duration: int) -> float:
117 |         step = min(step / duration, 1.0)
118 |         return delta * math.pow(step, 5) + start
119 | 
120 |     @staticmethod
121 |     def out_quint(step: float, start: Number, delta: Number, duration: int) -> float:
122 |         step = min(step / duration, 1.0)
123 |         return delta * (math.pow(step - 1, 5) + 1) + start
124 | 
125 |     @staticmethod
126 |     def in_out_quint(step: float, start: Number, delta: Number, duration: int) -> float:
127 |         step = min(step / (duration / 2), 2.0)
128 |         if step < 1:
129 |             return delta / 2 * math.pow(step, 5) + start
130 | 
131 |         return delta / 2 * (math.pow(step - 2, 5) + 2) + start
132 | 
133 |     #############################################################
134 |     # EXPONENTIAL
135 |     #############################################################
136 |     @staticmethod
137 |     def in_expo(step: float, start: Number, delta: Number, duration: int) -> float:
138 |         step = min(step / duration, 1.0)
139 |         return delta * math.pow(2, 10 * (step - 1)) + start
140 | 
141 |     @staticmethod
142 |     def out_expo(step: float, start: Number, delta: Number, duration: int) -> float:
143 |         step = min(step / duration, 1.0)
144 |         if step == 1.0:
145 |             return start + delta
146 |         return delta * (1 - math.pow(2, -10 * step)) + start
147 | 
148 |     @staticmethod
149 |     def in_out_expo(step: float, start: Number, delta: Number, duration: int) -> float:
150 |         step = min(step / (duration / 2), 2.0)
151 |         if step == 0.0:
152 |             return start
153 |         elif 0.0 < step < 1.0:
154 |             return delta / 2 * math.pow(2, 10 * (step - 1)) + start
155 |         elif step == 2.0:
156 |             return start + delta
157 | 
158 |         return delta / 2 * (2 - math.pow(2, -10 * (step - 1))) + start
159 | 
160 |     #############################################################
161 |     # CIRCULAR
162 |     #############################################################
163 |     @staticmethod
164 |     def in_circ(step: float, start: Number, delta: Number, duration: int) -> float:
165 |         step = min(step / duration, 1.0)
166 |         return -delta * (math.sqrt(1 - math.pow(step, 2)) - 1) + start
167 | 
168 |     @staticmethod
169 |     def out_circ(step: float, start: Number, delta: Number, duration: int) -> float:
170 |         step = min(step / duration, 1.0)
171 |         return delta * math.sqrt(1 - math.pow(step - 1, 2)) + start
172 | 
173 |     @staticmethod
174 |     def in_out_circ(step: float, start: Number, delta: Number, duration: int) -> float:
175 |         step = min(step / (duration / 2), 2.0)
176 |         if step < 1:
177 |             return delta / 2 * (1 - math.sqrt(1 - math.pow(step, 2))) + start
178 | 
179 |         return delta / 2 * (math.sqrt(1 - math.pow(step - 2, 2)) + 1) + start
180 | 
181 |     #############################################################################
182 |     # SPECIAL FUNCTIONS
183 |     # From: https://web.archive.org/web/20181122181216/http://kodhus.com/easings/
184 |     # P.S. The original link is dead :(
185 |     #############################################################################
186 |     @staticmethod
187 |     def in_back(step: float, start: Number, delta: Number, duration: int) -> float:
188 |         C1 = 1.70158
189 |         step = min(step / duration, 1.0)
190 |         if step == 1.0:
191 |             return start + delta
192 |         return delta * math.pow(step, 2) * ((C1 + 1) * step - C1) + start
193 | 
194 |     @staticmethod
195 |     def out_back(step: float, start: Number, delta: Number, duration: int) -> float:
196 |         C1 = 1.70158
197 |         step = min(step / duration, 1.0)
198 |         if step == 1.0:
199 |             return start + delta
200 |         return delta * (math.pow(step - 1, 2) * ((C1 + 1) * (step - 1) + C1) + 1) + start
201 | 
202 |     @staticmethod
203 |     def in_out_back(step: float, start: Number, delta: Number, duration: int) -> float:
204 |         C2 = 2.5949095
205 |         step = min(step / (duration / 2), 2.0)
206 | 
207 |         if step < 1:
208 |             return delta / 2 * (step * step * ((C2 + 1) * step - C2)) + start
209 | 
210 |         step -= 2
211 |         return delta / 2 * (step * step * ((C2 + 1) * step + C2) + 2) + start
212 | 
213 |     @staticmethod
214 |     def in_elastic(step: float, start: Number, delta: Number, duration: int) -> float:
215 |         s = 1.70158
216 |         p, a = 0, delta
217 | 
218 |         if step == 0:
219 |             return start
220 | 
221 |         step = min(step / duration, 1.0)
222 |         if step == 1:
223 |             return start + delta
224 | 
225 |         if p == 0:
226 |             p = duration * .3
227 | 
228 |         if a < math.fabs(delta):
229 |             a = delta
230 |             s = p / 4
231 |         else:
232 |             s = p / TAU * math.asin(delta / a)
233 | 
234 |         step -= 1
235 |         return -(a * math.pow(2, 10 * step) * math.sin((step * duration - s) * TAU / p)) + start
236 | 
237 |     @staticmethod
238 |     def out_elastic(step: float, start: Number, delta: Number, duration: int) -> float:
239 |         s = 1.70158
240 |         p, a = 0, delta
241 | 
242 |         if step == 0:
243 |             return start
244 | 
245 |         step = min(step / duration, 1.0)
246 |         if step == 1:
247 |             return start + delta
248 | 
249 |         if p == 0:
250 |             p = duration * .3
251 | 
252 |         if a < math.fabs(delta):
253 |             a = delta
254 |             s = p / 4
255 |         else:
256 |             s = p / TAU * math.asin(delta / a)
257 | 
258 |         return a * math.pow(2, -10 * step) * math.sin((step * duration - s) * TAU / p) + delta + start
259 | 
260 |     @staticmethod
261 |     def in_out_elastic(step: float, start: Number, delta: Number, duration: int) -> float:
262 |         s = 1.70158
263 |         p, a = 0, delta
264 | 
265 |         if step == 0:
266 |             return start
267 | 
268 |         step = min(step / (duration / 2), 2.0)
269 |         if step == 2:
270 |             return start + delta
271 | 
272 |         if p == 0:
273 |             p = duration * .3 * 1.5
274 | 
275 |         if a < math.fabs(delta):
276 |             a = delta
277 |             s = p / 4
278 |         else:
279 |             s = p / TAU * math.asin(delta / a)
280 | 
281 |         if step < 1:
282 |             step -= 1
283 |             return -.5 * a * math.pow(2, 10 * step) * math.sin((step * duration - s) * TAU / p) + start
284 | 
285 |         step -= 1
286 |         return a * math.pow(2, -10 * step) * math.sin((step * duration - s) * TAU / p) * .5 + delta + start
287 | 
288 |     @staticmethod
289 |     def in_bounce(step: float, start: Number, delta: Number, duration: int) -> float:
290 |         return delta - Ease2.out_bounce(duration - step, 0, delta, duration) + start
291 | 
292 |     @staticmethod
293 |     def out_bounce(step: float, start: Number, delta: Number, duration: int) -> float:
294 |         step = min(step / duration, 1.0)
295 | 
296 |         if step < 0.0:
297 |             step = 0.0
298 | 
299 |         if step < (1 / 2.75):
300 |             return delta * (7.5625 * math.pow(step, 2)) + start
301 |         elif step < (2 / 2.75):
302 |             return delta * (7.5625 * math.pow(step - (1.5 / 2.75), 2) + .75) + start
303 |         elif step < (2.5 / 2.75):
304 |             return delta * (7.5625 * math.pow(step - (2.25 / 2.75), 2) + .9375) + start
305 |         else:
306 |             return delta * (7.5625 * math.pow(step - (2.625 / 2.75), 2) + .984375) + start
307 | 
308 |     @staticmethod
309 |     def in_out_bounce(step: float, start: Number, delta: Number, duration: int) -> float:
310 |         if step < duration / 2:
311 |             return Ease2.in_bounce(step * 2, 0, delta, duration) * .5 + start
312 |         return Ease2.out_bounce(step * 2 - duration, 0, delta, duration) * .5 + delta * .5 + start
313 | 


--------------------------------------------------------------------------------
/tests/test_ease.py:
--------------------------------------------------------------------------------
  1 | from unittest import TestCase
  2 | from ease import Ease
  3 | 
  4 | 
  5 | class TestEase(TestCase):
  6 |     def test_linear(self):
  7 |         self.assertEqual(0.0, Ease.linear(0.0))
  8 |         self.assertEqual(1.0, Ease.linear(1.0))
  9 | 
 10 |     def test_in_sine(self):
 11 |         self.assertEqual(0.0, Ease.in_sine(0.0))
 12 |         self.assertEqual(1.0, Ease.in_sine(1.0))
 13 | 
 14 |     def test_out_sine(self):
 15 |         self.assertEqual(0.0, Ease.out_sine(0.0))
 16 |         self.assertEqual(1.0, Ease.out_sine(1.0))
 17 | 
 18 |     def test_in_out_sine(self):
 19 |         self.assertEqual(0.0, Ease.in_out_sine(0.0))
 20 |         self.assertEqual(1.0, Ease.in_out_sine(1.0))
 21 | 
 22 |     def test_in_quad(self):
 23 |         self.assertEqual(0.0, Ease.in_quad(0.0))
 24 |         self.assertEqual(1.0, Ease.in_quad(1.0))
 25 | 
 26 |     def test_out_quad(self):
 27 |         self.assertEqual(0.0, Ease.out_quad(0.0))
 28 |         self.assertEqual(1.0, Ease.out_quad(1.0))
 29 | 
 30 |     def test_in_out_quad(self):
 31 |         self.assertEqual(0.0, Ease.in_out_quad(0.0))
 32 |         self.assertEqual(1.0, Ease.in_out_quad(1.0))
 33 | 
 34 |     def test_in_cubic(self):
 35 |         self.assertEqual(0.0, Ease.in_cubic(0.0))
 36 |         self.assertEqual(1.0, Ease.in_cubic(1.0))
 37 | 
 38 |     def test_out_cubic(self):
 39 |         self.assertEqual(0.0, Ease.out_cubic(0.0))
 40 |         self.assertEqual(1.0, Ease.out_cubic(1.0))
 41 | 
 42 |     def test_in_out_cubic(self):
 43 |         self.assertEqual(0.0, Ease.in_out_cubic(0.0))
 44 |         self.assertEqual(1.0, Ease.in_out_cubic(1.0))
 45 | 
 46 |     def test_in_quart(self):
 47 |         self.assertEqual(0.0, Ease.in_quart(0.0))
 48 |         self.assertEqual(1.0, Ease.in_quart(1.0))
 49 | 
 50 |     def test_out_quart(self):
 51 |         self.assertEqual(0.0, Ease.out_quart(0.0))
 52 |         self.assertEqual(1.0, Ease.out_quart(1.0))
 53 | 
 54 |     def test_in_out_quart(self):
 55 |         self.assertEqual(0.0, Ease.in_out_quart(0.0))
 56 |         self.assertEqual(1.0, Ease.in_out_quart(1.0))
 57 | 
 58 |     def test_in_quint(self):
 59 |         self.assertEqual(0.0, Ease.in_quint(0.0))
 60 |         self.assertEqual(1.0, Ease.in_quint(1.0))
 61 | 
 62 |     def test_out_quint(self):
 63 |         self.assertEqual(0.0, Ease.out_quint(0.0))
 64 |         self.assertEqual(1.0, Ease.out_quint(1.0))
 65 | 
 66 |     def test_in_out_quint(self):
 67 |         self.assertEqual(0.0, Ease.in_out_quint(0.0))
 68 |         self.assertEqual(1.0, Ease.in_out_quint(1.0))
 69 | 
 70 |     def test_in_expo(self):
 71 |         self.assertEqual(0.0, Ease.in_expo(0.0))
 72 |         self.assertEqual(1.0, Ease.in_expo(1.0))
 73 | 
 74 |     def test_out_expo(self):
 75 |         self.assertEqual(0.0, Ease.out_expo(0.0))
 76 |         self.assertEqual(1.0, Ease.out_expo(1.0))
 77 | 
 78 |     def test_in_out_expo(self):
 79 |         self.assertEqual(0.0, Ease.in_out_expo(0.0))
 80 |         self.assertEqual(1.0, Ease.in_out_expo(1.0))
 81 | 
 82 |     def test_in_circ(self):
 83 |         self.assertEqual(0.0, Ease.in_circ(0.0))
 84 |         self.assertEqual(1.0, Ease.in_circ(1.0))
 85 | 
 86 |     def test_out_circ(self):
 87 |         self.assertEqual(0.0, Ease.out_circ(0.0))
 88 |         self.assertEqual(1.0, Ease.out_circ(1.0))
 89 | 
 90 |     def test_in_out_circ(self):
 91 |         self.assertEqual(0.0, Ease.in_out_circ(0.0))
 92 |         self.assertEqual(1.0, Ease.in_out_circ(1.0))
 93 | 
 94 |     def test_in_back(self):
 95 |         self.assertEqual(0.0, Ease.in_back(0.0))
 96 |         self.assertEqual(1.0, Ease.in_back(1.0))
 97 | 
 98 |     def test_out_back(self):
 99 |         self.assertEqual(0.0, Ease.out_back(0.0))
100 |         self.assertEqual(1.0, Ease.out_back(1.0))
101 | 
102 |     def test_in_out_back(self):
103 |         self.assertEqual(0.0, Ease.in_out_back(0.0))
104 |         self.assertEqual(1.0, Ease.in_out_back(1.0))
105 | 
106 |     def test_in_elastic(self):
107 |         self.assertEqual(0.0, Ease.in_elastic(0.0))
108 |         self.assertEqual(1.0, Ease.in_elastic(1.0))
109 | 
110 |     def test_out_elastic(self):
111 |         self.assertEqual(0.0, Ease.out_elastic(0.0))
112 |         self.assertEqual(1.0, Ease.out_elastic(1.0))
113 | 
114 |     def test_in_out_elastic(self):
115 |         self.assertEqual(0.0, Ease.in_out_elastic(0.0))
116 |         self.assertEqual(1.0, Ease.in_out_elastic(1.0))
117 | 
118 |     def test_in_bounce(self):
119 |         self.assertEqual(0.0, Ease.in_bounce(0.0))
120 |         self.assertEqual(1.0, Ease.in_bounce(1.0))
121 | 
122 |     def test_out_bounce(self):
123 |         self.assertEqual(0.0, Ease.out_bounce(0.0))
124 |         self.assertEqual(1.0, Ease.out_bounce(1.0))
125 | 
126 |     def test_in_out_bounce(self):
127 |         self.assertEqual(0.0, Ease.in_out_bounce(0.0))
128 |         self.assertEqual(1.0, Ease.in_out_bounce(1.0))
129 | 


--------------------------------------------------------------------------------
/tests/test_ease2.py:
--------------------------------------------------------------------------------
  1 | from unittest import TestCase
  2 | from ease2 import Ease2
  3 | 
  4 | 
  5 | class TestEase2(TestCase):
  6 |     def setUp(self):
  7 |         self.t = 3000
  8 |         self.b = 0
  9 |         self.c = 500
 10 |         self.d = 3000
 11 | 
 12 |     def test_linear(self):
 13 |         v = Ease2.linear(self.t, self.b, self.c, self.d)
 14 |         self.assertEqual(self.c + self.b, v)
 15 | 
 16 |         v = Ease2.linear(self.t, self.c + self.b, -self.c, self.d)
 17 |         self.assertEqual(self.b, v)
 18 | 
 19 |     def test_in_sine(self):
 20 |         v = Ease2.in_sine(self.t, self.b, self.c, self.d)
 21 |         self.assertEqual(self.c + self.b, v)
 22 | 
 23 |         v = Ease2.in_sine(self.t, self.c + self.b, -self.c, self.d)
 24 |         self.assertEqual(self.b, v)
 25 | 
 26 |     def test_out_sine(self):
 27 |         v = Ease2.out_sine(self.t, self.b, self.c, self.d)
 28 |         self.assertEqual(self.c + self.b, v)
 29 | 
 30 |         v = Ease2.out_sine(self.t, self.c + self.b, -self.c, self.d)
 31 |         self.assertEqual(self.b, v)
 32 | 
 33 |     def test_in_out_sine(self):
 34 |         v = Ease2.in_out_sine(self.t, self.b, self.c, self.d)
 35 |         self.assertEqual(self.c + self.b, v)
 36 | 
 37 |         v = Ease2.in_out_sine(self.t, self.c + self.b, -self.c, self.d)
 38 |         self.assertEqual(self.b, v)
 39 | 
 40 |     def test_in_quad(self):
 41 |         v = Ease2.in_quad(self.t, self.b, self.c, self.d)
 42 |         self.assertEqual(self.c + self.b, v)
 43 | 
 44 |         v = Ease2.in_quad(self.t, self.c + self.b, -self.c, self.d)
 45 |         self.assertEqual(self.b, v)
 46 | 
 47 |     def test_out_quad(self):
 48 |         v = Ease2.out_quad(self.t, self.b, self.c, self.d)
 49 |         self.assertEqual(self.c + self.b, v)
 50 | 
 51 |         v = Ease2.out_quad(self.t, self.c + self.b, -self.c, self.d)
 52 |         self.assertEqual(self.b, v)
 53 | 
 54 |     def test_in_out_quad(self):
 55 |         v = Ease2.in_out_quad(self.t, self.b, self.c, self.d)
 56 |         self.assertEqual(self.c + self.b, v)
 57 | 
 58 |         v = Ease2.in_out_quad(self.t, self.c + self.b, -self.c, self.d)
 59 |         self.assertEqual(self.b, v)
 60 | 
 61 |     def test_in_cubic(self):
 62 |         v = Ease2.in_cubic(self.t, self.b, self.c, self.d)
 63 |         self.assertEqual(self.c + self.b, v)
 64 | 
 65 |         v = Ease2.in_cubic(self.t, self.c + self.b, -self.c, self.d)
 66 |         self.assertEqual(self.b, v)
 67 | 
 68 |     def test_out_cubic(self):
 69 |         v = Ease2.out_cubic(self.t, self.b, self.c, self.d)
 70 |         self.assertEqual(self.c + self.b, v)
 71 | 
 72 |         v = Ease2.out_cubic(self.t, self.c + self.b, -self.c, self.d)
 73 |         self.assertEqual(self.b, v)
 74 | 
 75 |     def test_in_out_cubic(self):
 76 |         v = Ease2.in_out_cubic(self.t, self.b, self.c, self.d)
 77 |         self.assertEqual(self.c + self.b, v)
 78 | 
 79 |         v = Ease2.in_out_cubic(self.t, self.c + self.b, -self.c, self.d)
 80 |         self.assertEqual(self.b, v)
 81 | 
 82 |     def test_in_quart(self):
 83 |         v = Ease2.in_quart(self.t, self.b, self.c, self.d)
 84 |         self.assertEqual(self.c + self.b, v)
 85 | 
 86 |         v = Ease2.in_quart(self.t, self.c + self.b, -self.c, self.d)
 87 |         self.assertEqual(self.b, v)
 88 | 
 89 |     def test_out_quart(self):
 90 |         v = Ease2.out_quart(self.t, self.b, self.c, self.d)
 91 |         self.assertEqual(self.c + self.b, v)
 92 | 
 93 |         v = Ease2.out_quart(self.t, self.c + self.b, -self.c, self.d)
 94 |         self.assertEqual(self.b, v)
 95 | 
 96 |     def test_in_out_quart(self):
 97 |         v = Ease2.in_out_quart(self.t, self.b, self.c, self.d)
 98 |         self.assertEqual(self.c + self.b, v)
 99 | 
100 |         v = Ease2.in_out_quart(self.t, self.c + self.b, -self.c, self.d)
101 |         self.assertEqual(self.b, v)
102 | 
103 |     def test_in_quint(self):
104 |         v = Ease2.in_quint(self.t, self.b, self.c, self.d)
105 |         self.assertEqual(self.c + self.b, v)
106 | 
107 |         v = Ease2.in_quint(self.t, self.c + self.b, -self.c, self.d)
108 |         self.assertEqual(self.b, v)
109 | 
110 |     def test_out_quint(self):
111 |         v = Ease2.out_quint(self.t, self.b, self.c, self.d)
112 |         self.assertEqual(self.c + self.b, v)
113 | 
114 |         v = Ease2.out_quint(self.t, self.c + self.b, -self.c, self.d)
115 |         self.assertEqual(self.b, v)
116 | 
117 |     def test_in_out_quint(self):
118 |         v = Ease2.in_out_quint(self.t, self.b, self.c, self.d)
119 |         self.assertEqual(self.c + self.b, v)
120 | 
121 |         v = Ease2.in_out_quint(self.t, self.c + self.b, -self.c, self.d)
122 |         self.assertEqual(self.b, v)
123 | 
124 |     def test_in_expo(self):
125 |         v = Ease2.in_expo(self.t, self.b, self.c, self.d)
126 |         self.assertEqual(self.c + self.b, v)
127 | 
128 |         v = Ease2.in_expo(self.t, self.c + self.b, -self.c, self.d)
129 |         self.assertEqual(self.b, v)
130 | 
131 |     def test_out_expo(self):
132 |         v = Ease2.out_expo(self.t, self.b, self.c, self.d)
133 |         self.assertEqual(self.c + self.b, v)
134 | 
135 |         v = Ease2.out_expo(self.t, self.c + self.b, -self.c, self.d)
136 |         self.assertEqual(self.b, v)
137 | 
138 |     def test_in_out_expo(self):
139 |         v = Ease2.in_out_expo(self.t, self.b, self.c, self.d)
140 |         self.assertEqual(self.c + self.b, v)
141 | 
142 |         v = Ease2.in_out_expo(self.t, self.c + self.b, -self.c, self.d)
143 |         self.assertEqual(self.b, v)
144 | 
145 |     def test_in_circ(self):
146 |         v = Ease2.in_circ(self.t, self.b, self.c, self.d)
147 |         self.assertEqual(self.c + self.b, v)
148 | 
149 |         v = Ease2.in_circ(self.t, self.c + self.b, -self.c, self.d)
150 |         self.assertEqual(self.b, v)
151 | 
152 |     def test_out_circ(self):
153 |         v = Ease2.out_circ(self.t, self.b, self.c, self.d)
154 |         self.assertEqual(self.c + self.b, v)
155 | 
156 |         v = Ease2.out_circ(self.t, self.c + self.b, -self.c, self.d)
157 |         self.assertEqual(self.b, v)
158 | 
159 |     def test_in_out_circ(self):
160 |         v = Ease2.in_out_circ(self.t, self.b, self.c, self.d)
161 |         self.assertEqual(self.c + self.b, v)
162 | 
163 |         v = Ease2.in_out_circ(self.t, self.c + self.b, -self.c, self.d)
164 |         self.assertEqual(self.b, v)
165 | 
166 |     def test_in_back(self):
167 |         v = Ease2.in_back(self.t, self.b, self.c, self.d)
168 |         self.assertEqual(self.c + self.b, v)
169 | 
170 |         v = Ease2.in_back(self.t, self.c + self.b, -self.c, self.d)
171 |         self.assertEqual(self.b, v)
172 | 
173 |     def test_out_back(self):
174 |         v = Ease2.out_back(self.t, self.b, self.c, self.d)
175 |         self.assertEqual(self.c + self.b, v)
176 | 
177 |         v = Ease2.out_back(self.t, self.c + self.b, -self.c, self.d)
178 |         self.assertEqual(self.b, v)
179 | 
180 |     def test_in_out_back(self):
181 |         v = Ease2.in_out_back(self.t, self.b, self.c, self.d)
182 |         self.assertEqual(self.c + self.b, v)
183 | 
184 |         v = Ease2.in_out_back(self.t, self.c + self.b, -self.c, self.d)
185 |         self.assertEqual(self.b, v)
186 | 
187 |     def test_in_elastic(self):
188 |         v = Ease2.in_elastic(self.t, self.b, self.c, self.d)
189 |         self.assertEqual(self.c + self.b, v)
190 | 
191 |         v = Ease2.in_elastic(self.t, self.c + self.b, -self.c, self.d)
192 |         self.assertEqual(self.b, v)
193 | 
194 |     def test_out_elastic(self):
195 |         v = Ease2.out_elastic(self.t, self.b, self.c, self.d)
196 |         self.assertEqual(self.c + self.b, v)
197 | 
198 |         v = Ease2.out_elastic(self.t, self.c + self.b, -self.c, self.d)
199 |         self.assertEqual(self.b, v)
200 | 
201 |     def test_in_out_elastic(self):
202 |         v = Ease2.in_out_elastic(self.t, self.b, self.c, self.d)
203 |         self.assertEqual(self.c + self.b, v)
204 | 
205 |         v = Ease2.in_out_elastic(self.t, self.c + self.b, -self.c, self.d)
206 |         self.assertEqual(self.b, v)
207 | 
208 |     def test_in_bounce(self):
209 |         v = Ease2.in_bounce(self.t, self.b, self.c, self.d)
210 |         self.assertEqual(self.c + self.b, v)
211 | 
212 |         v = Ease2.in_bounce(self.t, self.c + self.b, -self.c, self.d)
213 |         self.assertEqual(self.b, v)
214 | 
215 |     def test_out_bounce(self):
216 |         v = Ease2.out_bounce(self.t, self.b, self.c, self.d)
217 |         self.assertEqual(self.c + self.b, v)
218 | 
219 |         v = Ease2.out_bounce(self.t, self.c + self.b, -self.c, self.d)
220 |         self.assertEqual(self.b, v)
221 | 
222 |     def test_in_out_bounce(self):
223 |         v = Ease2.in_out_bounce(self.t, self.b, self.c, self.d)
224 |         self.assertEqual(self.c + self.b, v)
225 | 
226 |         v = Ease2.in_out_bounce(self.t, self.c + self.b, -self.c, self.d)
227 |         self.assertEqual(self.b, v)
228 | 


--------------------------------------------------------------------------------
/tween.py:
--------------------------------------------------------------------------------
  1 | import time
  2 | from enum import Enum, auto
  3 | from ease import Ease
  4 | from collections.abc import Callable
  5 | 
  6 | 
  7 | class Easing(Enum):
  8 |     LINEAR = auto()
  9 |     SINE = auto()
 10 |     QUAD = auto()
 11 |     CUBIC = auto()
 12 |     QUART = auto()
 13 |     QUINT = auto()
 14 |     EXPO = auto()
 15 |     CIRC = auto()
 16 |     BACK = auto()
 17 |     ELASTIC = auto()
 18 |     BOUNCE = auto()
 19 | 
 20 | 
 21 | class EasingMode(Enum):
 22 |     IN = auto()
 23 |     OUT = auto()
 24 |     IN_OUT = auto()
 25 | 
 26 | 
 27 | class Tween:
 28 |     def __init__(self,
 29 |                  begin: float = 0.0, end: float = 1.0,
 30 |                  duration: int = 600,
 31 |                  easing: Easing = Easing.LINEAR,
 32 |                  easing_mode: EasingMode = EasingMode.IN,
 33 |                  boomerang: bool = False,
 34 |                  loop: bool = False,
 35 |                  reps: int = 0):
 36 | 
 37 |         self._begin = begin
 38 |         self._origin = begin
 39 |         self._end = end
 40 |         self._duration = duration
 41 |         self._boomerang = boomerang
 42 |         self._loop = loop
 43 |         self._reps = reps
 44 |         self._count = 1
 45 | 
 46 |         self._easing = easing
 47 |         self._easing_mode = easing_mode
 48 | 
 49 |         self._pause_start = 0
 50 |         self._pause_dur = 0
 51 |         self._paused = False
 52 | 
 53 |         self._start_time = 0
 54 |         self._animating = False
 55 |         self._value = self._begin
 56 |         self._step = 0
 57 | 
 58 |         # Determine which function to use
 59 |         self._ease: Callable[[float], float]
 60 |         self._eval_func()
 61 | 
 62 |     def _eval_func(self):
 63 |         match self._easing:
 64 |             case Easing.SINE:
 65 |                 match self._easing_mode:
 66 |                     case EasingMode.IN:
 67 |                         self._ease = Ease.in_sine
 68 |                     case EasingMode.OUT:
 69 |                         self._ease = Ease.out_sine
 70 |                     case EasingMode.IN_OUT:
 71 |                         self._ease = Ease.in_out_sine
 72 |             case Easing.QUAD:
 73 |                 match self._easing_mode:
 74 |                     case EasingMode.IN:
 75 |                         self._ease = Ease.in_quad
 76 |                     case EasingMode.OUT:
 77 |                         self._ease = Ease.out_quad
 78 |                     case EasingMode.IN_OUT:
 79 |                         self._ease = Ease.in_out_quad
 80 |             case Easing.CUBIC:
 81 |                 match self._easing_mode:
 82 |                     case EasingMode.IN:
 83 |                         self._ease = Ease.in_cubic
 84 |                     case EasingMode.OUT:
 85 |                         self._ease = Ease.out_cubic
 86 |                     case EasingMode.IN_OUT:
 87 |                         self._ease = Ease.in_out_cubic
 88 |             case Easing.QUART:
 89 |                 match self._easing_mode:
 90 |                     case EasingMode.IN:
 91 |                         self._ease = Ease.in_quart
 92 |                     case EasingMode.OUT:
 93 |                         self._ease = Ease.out_quart
 94 |                     case EasingMode.IN_OUT:
 95 |                         self._ease = Ease.in_out_quart
 96 |             case Easing.QUINT:
 97 |                 match self._easing_mode:
 98 |                     case EasingMode.IN:
 99 |                         self._ease = Ease.in_quint
100 |                     case EasingMode.OUT:
101 |                         self._ease = Ease.out_quint
102 |                     case EasingMode.IN_OUT:
103 |                         self._ease = Ease.in_out_quint
104 |             case Easing.EXPO:
105 |                 match self._easing_mode:
106 |                     case EasingMode.IN:
107 |                         self._ease = Ease.in_expo
108 |                     case EasingMode.OUT:
109 |                         self._ease = Ease.out_expo
110 |                     case EasingMode.IN_OUT:
111 |                         self._ease = Ease.in_out_expo
112 |             case Easing.CIRC:
113 |                 match self._easing_mode:
114 |                     case EasingMode.IN:
115 |                         self._ease = Ease.in_circ
116 |                     case EasingMode.OUT:
117 |                         self._ease = Ease.out_circ
118 |                     case EasingMode.IN_OUT:
119 |                         self._ease = Ease.in_out_circ
120 |             case Easing.BACK:
121 |                 match self._easing_mode:
122 |                     case EasingMode.IN:
123 |                         self._ease = Ease.in_back
124 |                     case EasingMode.OUT:
125 |                         self._ease = Ease.out_back
126 |                     case EasingMode.IN_OUT:
127 |                         self._ease = Ease.in_out_back
128 |             case Easing.ELASTIC:
129 |                 match self._easing_mode:
130 |                     case EasingMode.IN:
131 |                         self._ease = Ease.in_elastic
132 |                     case EasingMode.OUT:
133 |                         self._ease = Ease.out_elastic
134 |                     case EasingMode.IN_OUT:
135 |                         self._ease = Ease.in_out_elastic
136 |             case Easing.BOUNCE:
137 |                 match self._easing_mode:
138 |                     case EasingMode.IN:
139 |                         self._ease = Ease.in_bounce
140 |                     case EasingMode.OUT:
141 |                         self._ease = Ease.out_bounce
142 |                     case EasingMode.IN_OUT:
143 |                         self._ease = Ease.in_out_bounce
144 |             case _:
145 |                 self._ease = Ease.linear
146 | 
147 |     def start(self):
148 |         if not self.animating:
149 |             self._start_time = time.time()
150 |             self._animating = True
151 | 
152 |     @property
153 |     def easing_mode(self):
154 |         return self._easing_mode
155 | 
156 |     @easing_mode.setter
157 |     def easing_mode(self, value):
158 |         self._easing_mode = value
159 |         self._eval_func()
160 | 
161 |     @property
162 |     def step(self):
163 |         return self._step
164 | 
165 |     @property
166 |     def value(self):
167 |         return self._value
168 | 
169 |     @property
170 |     def animating(self):
171 |         return self._animating
172 | 
173 |     def pause(self):
174 |         if not self._paused:
175 |             self._paused = True
176 |             self._pause_start = time.time()
177 | 
178 |     def resume(self):
179 |         if self._paused:
180 |             self._paused = False
181 |             self._pause_dur = time.time() - self._pause_start
182 |             self._start_time += self._pause_dur
183 | 
184 |     def update(self):
185 |         if self.animating and not self._paused:
186 |             this_time = time.time()
187 |             elapsed = (this_time - self._start_time) * 1000.0  # convert to ms
188 |             self._step = min(elapsed / self._duration, 1.0)
189 |             delta = self._end - self._begin
190 | 
191 |             # Normalized version
192 |             self._value = self._ease(self.step) * delta + self._begin
193 |             # Absolute version
194 |             # self._value = Ease2.linear(elapsed, self._begin, delta, self._duration)
195 | 
196 |             # Once this is the end of the animation state...
197 |             if self.step == 1.0:
198 |                 if self._boomerang:
199 |                     self._start_time = this_time
200 |                     self._begin, self._end = self._end, self._begin
201 | 
202 |                     if self.value == self._origin:
203 |                         if self._loop:
204 |                             self._do_loop()
205 |                         else:
206 |                             self._animating = False
207 |                 else:
208 |                     if self._loop:
209 |                         self._do_loop()
210 |                     else:
211 |                         self._animating = False
212 | 
213 |     def _do_loop(self):
214 |         if self._reps == 0:
215 |             self._animating = False
216 |             self.start()
217 |         else:
218 |             if self._count < self._reps:
219 |                 self._count += 1
220 |                 self._animating = False
221 |                 self.start()
222 |             else:
223 |                 self._count = 1
224 |                 self._animating = False
225 | 


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