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<canvas id="myCanvas" />
canvas {
border: 1px solid grey;
}
function getLines(ctx, text, maxWidth) {
var words = text.split(" ");
var lines = [];
var currentLine = words[0];
for (var i = 1; i < words.length; i++) {
var word = words[i];
var width = ctx.measureText(currentLine + " " + word).width;
if (width < maxWidth) {
currentLine += " " + word;
} else {
lines.push(currentLine);
currentLine = word;
}
}
lines.push(currentLine);
return lines;
}
let loadImageOnCanvasAndThenWriteText = (
canvas,
imageUrl,
textToWrite,
textStyleOptions,
xCordOfText,
yCordOfText,
textBoundingBoxWidth
) => {
// Get the 2D Context from the canvas
let ctx = canvas.getContext("2d");
// Create a new Image
let img = new Image();
// Setting up a function with the code to run after the image is loaded
img.onload = () => {
// Once the image is loaded, we will get the width & height of the image
let loadedImageWidth = img.width;
let loadedImageHeight = img.height;
// Set the canvas to the same size as the image.
canvas.width = loadedImageWidth;
canvas.height = loadedImageHeight;
// Draw the image on to the canvas.
ctx.drawImage(img, 0, 0);
// Set all the properties of the text based on the input params
ctx.font = `${textStyleOptions.fontSize}px ${textStyleOptions.fontFamily}`;
ctx.fillStyle = textStyleOptions.textColor;
ctx.textAlign = textStyleOptions.textAlign;
// Setting this so that the postion of the text can be set
// based on the x and y cord from the top right corner
ctx.textBaseline = "top";
// Get lines array
let arrayOfLines = getLines(ctx, textToWrite, textBoundingBoxWidth);
// Set line height as a little bit bigger than the font size
let lineheight = textStyleOptions.fontSize + 10;
// Loop over each of the lines and write it over the canvas
for (let i = 0; i < arrayOfLines.length; i++) {
ctx.fillText(arrayOfLines[i], xCordOfText, yCordOfText + i * lineheight);
}
};
// Now that we have set up the image "onload" handeler, we can assign
// an image URL to the image.
img.src = imageUrl;
};
document.fonts.load('100px "Mouse Memoirs"').then(() => {
// Setting up the canvas
let theCanvas = document.getElementById("myCanvas");
// Some image URL..
let imageUrl =
"https://livefiredev.com/wp-content/uploads/2022/08/mona-lisa.jpeg";
let textStyleOptions = {
fontSize: 25,
fontFamily: "Mouse Memoirs",
textColor: "rgba(255, 255, 255, 0.9)",
textAlign: "left"
};
let textToWrite =
"The Mona Lisa is one of the most valuable paintings in the world.";
let xCordOfText = 10;
let yCordOfText = 10;
let textBoundingBoxWidth = 350;
// Load image on the canvas & then write text
loadImageOnCanvasAndThenWriteText(
theCanvas,
imageUrl,
textToWrite,
textStyleOptions,
xCordOfText,
yCordOfText,
textBoundingBoxWidth
);
});
Also see: Tab Triggers