2D Capacitive Touchscreen Grid Sensing Simulator

This simulator visualizes what a touchscreen controller actually measures: a grid of row and column electrodes, each crossing holding a small baseline mutual capacitance. Dragging a virtual finger over the grid locally increases the coupling to ground and pulls the capacitance down at nearby nodes with an inverse-square-like falloff, painted live as a heatmap. A simple peak-finding and weighted-centroid algorithm scans the whole grid every frame and reconstructs the touch position from the capacitance dip alone — drag the second dot to see the same scan resolve two simultaneous contacts (multi-touch), and use the sliders to see how grid density, contact strength, field radius and sensor noise change localization accuracy.