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@jan-j
Created January 9, 2018 16:04
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const path = require('path');
const fs = require('fs');
const Canvas = require('canvas');
const targetWidth = 6000;
const targetHeight = 50;
const deltaX = 50;
const sourceWidth = deltaX * 20
const sourceHeight = targetHeight * 20;
const sourceCanvas = new Canvas(sourceWidth, sourceHeight);
sourceCanvas.getContext('2d').fillStyle = 'red';
sourceCanvas.getContext('2d').fillRect(0, 0, sourceWidth, sourceHeight);
const targetCanvas = new Canvas(targetWidth, targetHeight);
targetCanvas.getContext('2d').fillStyle = 'blue';
targetCanvas.getContext('2d').fillRect(0, 0, targetWidth, targetHeight);
for (let x = 0; x < targetWidth; x = x + deltaX) {
targetCanvas.getContext('2d').drawImage(
sourceCanvas,
0,
0,
sourceWidth,
sourceHeight,
x,
0,
deltaX,
targetHeight
);
}
fs.writeFileSync(
path.join(__dirname, 'target.png'),
new Buffer(
targetCanvas.toDataURL('image/png').replace(/^data.*?;base64,/, ''),
'base64'
)
);
const path = require('path');
const fs = require('fs');
const { createCanvas } = require('canvas');
const targetWidth = 6000;
const targetHeight = 50;
const deltaX = 50;
const sourceWidth = deltaX * 20
const sourceHeight = targetHeight * 20;
const sourceCanvas = createCanvas(sourceWidth, sourceHeight);
sourceCanvas.getContext('2d').fillStyle = 'red';
sourceCanvas.getContext('2d').fillRect(0, 0, sourceWidth, sourceHeight);
const targetCanvas = createCanvas(targetWidth, targetHeight);
targetCanvas.getContext('2d').fillStyle = 'blue';
targetCanvas.getContext('2d').fillRect(0, 0, targetWidth, targetHeight);
for (let x = 0; x < targetWidth; x = x + deltaX) {
targetCanvas.getContext('2d').drawImage(
sourceCanvas,
0,
0,
sourceWidth,
sourceHeight,
x,
0,
deltaX,
targetHeight
);
}
fs.writeFileSync(
path.join(__dirname, 'target.png'),
new Buffer(
targetCanvas.toDataURL('image/png').replace(/^data.*?;base64,/, ''),
'base64'
)
);
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