Re: [NTG-context] Zooming in to a specific part of the page

On Wed, 17 Nov 2010, Mojca Miklavec wrote:


On Wed, Nov 17, 2010 at 01:52, Aditya Mahajan wrote:

Hi,

Is it possible to zoom into a specific part of the page? I am thinking of
the following scenario. Suppose I have the following document

\setuppapersize[S6][S6]
\starttext
\placefigure[right,none]{\externalfigure[dummy][width=0.3\textwidth]}
\input knuth

\page

\input tufte

\stoptext

I want that when I click on the image, the pdf is zoomed in so that the
image occupies the full screen[1], and when I click on the zoomed in image,
it zooms out and I get the previous page view.

How do I achieve this? I am guessing that some javascript magic might be
needed, but I do not understand the interaction code at all. This feature
will be pretty handy for presentations.


You don't need JavaScript. You can use a normal hyperlink:

[page /FitR left bottom right top]


I hope that I do not have to write raw PDF literals.


Display the page designated by page, with its contents magnified just
enough to fit the rectangle specified by the coordinates left, bottom,
right, and top entirely within the window both horizontally and
vertically. If the required horizontal and vertical magnification
factors are different, use the smaller of the two, centering the
rectangle within the window in the other dimension.

Section "8.2.1 Destinations" of PDFReference16.pdf


Thanks.


You only need to find a way to transfer the data from nice interface
in ConTeXt into PDF literals.



I don't know if this data is available when a figure is being placed. At the very least, I need to know the xy location of one of the corners of the figure (and can compute other corners based on height and width)


PS: in case that you start hacking with that, please also convince
Hans to fix hyperlinks in formulas/chapters/tables/... (see equation
\in[eq:formulalabel]) to point to specific location on some page, not
to the whole page.



I thought that you were the most persuasive person :) This has been around for a while. Maybe we should open a tracker item for it.