We built Render Engine, a mockup SaaS with a WebGL editor and three Nuxt apps. We can build yours.

const organizedData = () => {
  let distortionData = {
    enableWrapTool: true,
    numRows: numRows.value,
    numCols: numCols.value,
    scale: currentScale.value,
    currentRotation: currentRotation.value,
    currentXPosition: currentXPosition.value,
    currentYPosition: currentYPosition.value,
    cornerLocalX: cornerLocalX.value,
    cornerLocalY: cornerLocalY.value,
    controlPoints: controlPoints,
    rotationGroup: {
      position: rotationGroup.position,
      rotation: rotationGroup.rotation,
    },
  };
  canvasStore.setRenderSettings(distortionData);
  canvasStore.setIsLocalDistortionEnabled(true);
  return distortionData;
};

async function initBrowser() {
  if (browserInstance) return browserInstance;

  if (isInitializing) {
    while (isInitializing) {
      await new Promise((resolve) => setTimeout(resolve, 100));
    }
    return browserInstance;
  }

  try {
    isInitializing = true;
    browserInstance = await puppeteer.launch({
      args: chromium.args,
      executablePath: await chromium.executablePath(
        "https://github.com/Sparticuz/chromium/releases/download/v119.0.2/chromium-v119.0.2-pack.tar"
      ),
      headless: chromium.headless,
    });
    return browserInstance;
  } finally {
    isInitializing = false;
  }
}

function calculateFFDPoint(u, v) {
  const curveX = [];

  // Adjust interpolation for special cases
  for (let i = 0; i < numRows; i++) {
    const points = [];
    for (let j = 0; j < numCols; j++) {
      points.push(controlPoints[i * numCols + j].position.clone());
    }

    let interpolatedPoint;
    if (numCols === 2) {
      // Linear interpolation for 2 columns
      const start = points[0];
      const end = points[1];
      interpolatedPoint = new THREE.Vector3(
        start.x + (end.x - start.x) * u,
        start.y + (end.y - start.y) * u,
        0
      );
    } else {
      // Curve interpolation for 3 or more columns
      const horizontalCurve = new THREE.CatmullRomCurve3(points);
      interpolatedPoint = horizontalCurve.getPoint(u);
    }
    curveX.push(interpolatedPoint);
  }
  // …

const canvas = new fabric.Canvas(null, {
  width: renderLayerImageDimensions.renderLayerImageWidth || 1000,
  height: renderLayerImageDimensions.renderLayerImageHeight || 1000,
  enableRetinaScaling: false, // Performance improvement
  renderOnAddRemove: false,
});

// Load objects into canvas
await new Promise((resolve) => {
  canvas.loadFromJSON(fabricCanvas, () => {
    canvas.renderAll();
    resolve();
  });
});

// Calculate scale factors between screen coordinates and SVG viewBox coordinates
// The frontend sends coordinates based on how the SVG is displayed on screen
// We need to convert these to SVG viewBox coordinates
const scaleX = viewBoxWidth / originalWidth;
const scaleY = viewBoxHeight / originalHeight;

// Convert frontend crop coordinates to SVG viewBox coordinates
const svgCropX = viewBoxX + left * scaleX;
const svgCropY = viewBoxY + top * scaleY;
const svgCropWidth = width * scaleX;
const svgCropHeight = height * scaleY;

const originalUrl = image.image.url;

// Save the image first with original URL for immediate response
const savedImage = await this.prisma.file.create({
  data: {
    url: originalUrl, // Keep original high-res URL
    optimizedUrl: originalUrl, // Temporary - will be updated
    thumbnailUrl: originalUrl,  // Temporary - will be updated
    fileName: fileName,
    fileType: fileType,
    createdAt: new Date(),
    updatedAt: new Date(),
    ...(options.companyId && { companyId: options.companyId }),
    ...(options.customerId && { customerId: options.customerId }),
  },
});

// Process and upload optimized versions in the background (non-blocking)
this.processAndUploadOptimizedVersions(savedImage.id, originalUrl, fileName, options);

generateApiKey(): { keyId: string; secret: string; fullKey: string } {
  // Generate random bytes for key ID and secret
  const keyIdBytes = crypto.randomBytes(16)
  const secretBytes = crypto.randomBytes(32)

  // Create readable key ID and secret
  const keyId = this.KEY_PREFIX + keyIdBytes.toString('hex')
  const secret = this.SECRET_PREFIX + secretBytes.toString('hex')
  const fullKey = `${keyId}.${secret}`

  return { keyId, secret, fullKey }
}

/**
 * Generate checksum for integrity verification
 */
generateChecksum(keyId: string, secret: string): string {
  return crypto.createHash('sha256').update(`${keyId}:${secret}`).digest('hex')
}

// Get credit purchases in FIFO order (oldest first)
const creditPurchases = await tx.companyCreditPurchase.findMany({
  where: {
    companyId: data.companyId,
    creditsRemaining: { gt: 0 },
    status: CompanyCreditPurchaseStatus.COMPLETED,
  },
  orderBy: { purchasedAt: "asc" }, // FIFO: oldest first
});

// Deduct from each purchase until we've deducted enough
for (const purchase of creditPurchases) {
  if (remainingToDeduct <= 0) break;

  const deductFromThisPurchase = Math.min(
    remainingToDeduct,
    purchase.creditsRemaining
  );

  await tx.companyCreditPurchase.update({
    where: { id: purchase.id },
    data: {
      creditsUsed: { increment: deductFromThisPurchase },
      creditsRemaining: { decrement: deductFromThisPurchase },
      lastUsedAt: new Date(),
      // …
    },
  });

  remainingToDeduct -= deductFromThisPurchase;
}