Author: Nathan Sturtevant

Warning

Due: September 29th 2026, 2:00pm

Important

Click Use this template button (NOT fork) to create your repo based on it

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Background

Before starting this lab, please read the cpp references pages on std::function and this LearnC++ reference on lambda functions.

There is much more information on these pages than you need to understand at this point, but these are useful references with code examples of how to use lambda functions and std::function

Problems

Draw an animated circle

In the provided code, draw a circle that repeatedly moves from the left side to the right side of the screen. The y-location of the circle should be about 1/3 from the top of the screen and the x-location should be defined by the tween function given the number of elapsed frames. Decide and choose a constant for the number of frames per animation, and then use this to define the animation time. Then, pass that time into the tween function to get the circle location, and draw it to the screen.

Change the tween function

Implement nine different tween (easing) functions that are toggled between when you press the keys 1 to 9. You can take these functions from lecture, design them yourself, or use https://easings.net. You can look at the code when you click on a particular function, but you should implement it yourself in C++. When a key is pressed, the code should replace the global tween function with a new function written as a lambda expression.

Draw the tween function

At the bottom of the window plot the tween function. This plot should have an x-axis and a y-axis that go from $[0, 1]$ defining the bounds. Then, the code should loop from 0 to 1 sampling the tween function and drawing it on the screen. Example output is shown below. The code should draw the current location of the animation on this curve with a small circle.

Example Screenshot