How to plot negative x and y values on canvas?

@addison 

To plot negative x and y values on a canvas, you can simply adjust the origin point of your coordinate system. By default, the origin point in most canvas systems is at the top left corner with positive x values increasing to the right and positive y values increasing downwards.

To plot negative values, you can change the origin point to the center of the canvas or any other desired location. Here's an example code snippet in JavaScript to plot negative x and y values on a canvas:

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const canvas = document.getElementById('myCanvas');
const ctx = canvas.getContext('2d');

// Set the origin point to the center of the canvas
ctx.translate(canvas.width / 2, canvas.height / 2);

// Plot a point with negative x and y values
const x = -50;
const y = -50;

ctx.beginPath();
ctx.arc(x, y, 5, 0, 2*Math.PI);
ctx.fillStyle = 'red';
ctx.fill();
ctx.closePath();

In this code, we first get the canvas element and its 2D rendering context. We then use the translate method to set the origin point to the center of the canvas. Finally, we plot a point at the specified negative x and y values using the arc method.

By changing the origin point and adjusting the coordinate system, you can plot negative x and y values on the canvas.