How to animate an object using Arcade module?

Prerequisite: Arcade Library

The world of Programming is very vast, and animation is its key soul. In this, tutorial you will learn how to animate objects in Python using Arcade Module. Arcade is a present day Programming module used for developing 2D games with gripping sound and graphics.

Before starting with the article, you must revise your concepts of arcade Python module. To explain the whole concept of animating an object, Let’s take an example to understand it completely. You all must aware with the nested loop being in C, Python or Java and have probably created a lot of patterns using it. Here, we will animate a box with the help of arcade Python library. 

Step-by-step Approach:

Step1) Import arcade library.

Python3

# Import required module
import arcade

Step2) Here we will specify some parameters, that we will be using later in the program to declare width, height and title of the screen.

Python3

# Set up the constants

# Size of the screen
SCREEN_WIDTH = 720
SCREEN_HEIGHT = 480
SCREEN_TITLE = "Bouncing Box"

# Size of the rectangle
RECT_WIDTH = 50
RECT_HEIGHT = 50

Step3) Define the function for drawing the box  arcade.draw_rectangle_filled( ) Modify rectangles position based on the delta vector.

Python3

# Explicilt function generate animated bouncing box
def on_draw(delta_time):

    # Start the render.
    arcade.start_render()

    arcade.draw_rectangle_filled(on_draw.center_x, on_draw.center_y,
                                 RECT_WIDTH, RECT_HEIGHT,
                                 arcade.color.GREEN)

    on_draw.center_x += on_draw.delta_x * delta_time
    on_draw.center_y += on_draw.delta_y * delta_time

    # Figure out if we hit the edge and need to reverse.
    if on_draw.center_x < RECT_WIDTH // 2 \
            or on_draw.center_x > SCREEN_WIDTH - RECT_WIDTH // 2:
        on_draw.delta_x *= -1
    if on_draw.center_y < RECT_HEIGHT // 2 \
            or on_draw.center_y > SCREEN_HEIGHT - RECT_HEIGHT // 2:
        on_draw.delta_y *= -1

Step4:-Now, define function-specific variables. Also, we need to give them initial values. Then the values will persist between function calls.

Python3

# Set initial positions
on_draw.center_x = 100
on_draw.center_y = 50
on_draw.delta_x = 115
on_draw.delta_y = 130

Step5) Now, last step is define the main function. Under which, you need to define background colors.

Python3

# Driver code

# Open up our window
arcade.open_window(SCREEN_WIDTH, SCREEN_HEIGHT, SCREEN_TITLE)
arcade.set_background_color(arcade.color.WHITE)

# Tell the computer to call the draw command at the specified interval.
arcade.schedule(on_draw, 1 / 80)

# Run the program
arcade.run()

Below is the complete program of the above approach:

Python3

# Import required module
import arcade


# Set up the constants

# Size of the screen
SCREEN_WIDTH = 720
SCREEN_HEIGHT = 480
SCREEN_TITLE = "Bouncing Box"

# Size of the rectangle
RECT_WIDTH = 50
RECT_HEIGHT = 50


# Explicilt function generate animated bouncing box
def on_draw(delta_time):

    # Start the render.
    arcade.start_render()

    arcade.draw_rectangle_filled(on_draw.center_x, on_draw.center_y,
                                 RECT_WIDTH, RECT_HEIGHT,
                                 arcade.color.GREEN)

    on_draw.center_x += on_draw.delta_x * delta_time
    on_draw.center_y += on_draw.delta_y * delta_time

    # Figure out if we hit the edge and need to reverse.
    if on_draw.center_x < RECT_WIDTH // 2 \
            or on_draw.center_x > SCREEN_WIDTH - RECT_WIDTH // 2:
        on_draw.delta_x *= -1
    if on_draw.center_y < RECT_HEIGHT // 2 \
            or on_draw.center_y > SCREEN_HEIGHT - RECT_HEIGHT // 2:
        on_draw.delta_y *= -1


# Set initial positions
on_draw.center_x = 100
on_draw.center_y = 50
on_draw.delta_x = 115
on_draw.delta_y = 130


# Driver code

# Open up our window
arcade.open_window(SCREEN_WIDTH, SCREEN_HEIGHT, SCREEN_TITLE)
arcade.set_background_color(arcade.color.WHITE)

# Tell the computer to call the draw command at the specified interval.
arcade.schedule(on_draw, 1 / 80)

# Run the program
arcade.run()

Output: