Map mouse click/touch event position to pdf page coordinate

[benjinus]

Is there a way to map mouse click/touch event position to pdf page coordinate?

[ccxvii]

If you want the coordinates to use with PDFAnnotation or the other public methods of mupdf.js, you need to figure out the position relative to the page image that you display. Transform these coordinates by the display matrix you used to render the page to reverse any scaling you've applied.

If you need to convert to the internal PDF coordinate space, use the PDFPage getTransform matrix.

[benjinus]

@ccxvii

if the pdf page has no rotation, i can get the right coordinate by apply the matrix from PDFPage.getTransform. but if the page rotation is not 0, the coordinate applied with page matrix is not correct. any ideals why?

[ccxvii]

The transform matrix maps from the PDF page space. Did you invert the matrix to transform the other direction?

[benjinus]

@ccxvii

thanks, i will try invert the matrix.