// hidden-start import {camera} from "./cameraGasket" // hidden-end function imageIndex( width: number, x: number, y: number ) { return y * (width * 4) + x * 4; } export function plot( x: number, y: number, img: ImageData ) { let [pixelX, pixelY] = camera(img.width, x, y); const i = imageIndex( img.width, pixelX, pixelY ); // Skip pixels outside the display range if ( i < 0 || i > img.data.length ) { return; } // Set the pixel to black by writing 0 // to the first three elements at the index // (red, green, and blue, respectively), // and 255 to the last element (alpha) img.data[i] = 0; img.data[i + 1] = 0; img.data[i + 2] = 0; img.data[i + 3] = 0xff; }