This project used thermochromatic paint as well as a thermoelectric pad to activate the paint. The pad would be turned on using a capacitive sensor once a threshold was hit.
Below was a picture of the circuit in total. The picture also represents the thermochromatic paint before it was activated.
Here is another picture when the thermochromatic paint was partially activated.
Below is a schematic of the project. A very rough portrayal of the project.
Lastly shown below is the code that was used for the project. This code corresponds with the schematic above.