This example is for Processing 3+. If you have a previous version, use the examples included with your software. If you see any errors or have suggestions, please let us know.

**Moving On Curves.**

In this example, the circles moves along the curve y = x^4. Click the mouse to have it move to a new position.

float beginX = 20.0; // Initial x-coordinate float beginY = 10.0; // Initial y-coordinate float endX = 570.0; // Final x-coordinate float endY = 320.0; // Final y-coordinate float distX; // X-axis distance to move float distY; // Y-axis distance to move float exponent = 4; // Determines the curve float x = 0.0; // Current x-coordinate float y = 0.0; // Current y-coordinate float step = 0.01; // Size of each step along the path float pct = 0.0; // Percentage traveled (0.0 to 1.0) void setup() { size(640, 360); noStroke(); distX = endX - beginX; distY = endY - beginY; } void draw() { fill(0, 2); rect(0, 0, width, height); pct += step; if (pct < 1.0) { x = beginX + (pct * distX); y = beginY + (pow(pct, exponent) * distY); } fill(255); ellipse(x, y, 20, 20); } void mousePressed() { pct = 0.0; beginX = x; beginY = y; endX = mouseX; endY = mouseY; distX = endX - beginX; distY = endY - beginY; }