Bounding rectangle calculation / transformation

[jamesioppolo]

Can you please clarify the calculation of the bounding rectangle for the “Type Checking for Javascript” example shown on the webpage https://agentcooper.github.io/react-pdf-highlighter/ ?

Coordinate Values from PDF

A string find query on the PDF itself (https://arxiv.org/pdf/1708.08021.pdf) for the string “Type Checking for Javascript” obtains the following coordinate values:

const coordinatesFromPdf = {
  width: 298.81699979999996,
  height: 14.3462,
  str: "Fast and Precise Type Checking for JavaScript",
  transform: [14.3462, 0, 0, 14.3462, 45.828, 625.368], 
};

Hardcoded values in example

However, the hardcoded value in the example to highlight the subtext “Type Checking for javascript” requires the definition the hardcoded coordinates below (https://github.com/agentcooper/react-pdf-highlighter/blob/main/example/src/test-highlights.ts#L5)

const hardcodedCoordinates = {
  content: {
    text: " Type Checking for JavaScript",
  },
  position: {
    boundingRect: {
      x1: 255.73419189453125,
      y1: 139.140625,
      x2: 574.372314453125,
      y2: 165.140625,
      width: 809.9999999999999,
      height: 1200,
    },
    rects: [
      {
        ..as above...
      },
    ],
}

Transformation function

• Is it possible to explain how the values of x1, y1, x2, y2, width and height are obtained ?
• A transformation function would be a useful feature that would assist the highlighting arbitrary blocks of text

[RBSUS]

I think there is an argument that this library should be modified to use coordinatesFromPdf as the default highlight state, rather than the existing boundingRect approach. The former would enable more advanced manipulation of highlights and highlights to be added 'headlessly' without rendering the dom