Mouse position bug in string diagram editor

[epost]

Problem

There seems to be some multiplier >1 at work when moving blocks around in the string diagram editor. When you move the block to the right or down, it moves more than it should.

Steps

I haven't looked into what causes this yet. Any information on work on this would be appreicated.

[epost]

@marcosh Maybe you could have a look at this?

[marcosh]

I had a look at this. The problem is caused by different unit of measurement being used. Somewhere is pixels, somewhere else (the mouse position) is something else. I need to refresh a bit my frontend skills to fix it

[epost]

@marcosh Cool, thanks for the research! It might be the scale factor being used here and there. It's not absolutely necessary that you fix this thing btw; this mostly seemed like a good issue to start with qua familiarising yourself with the code.

[marcosh]

as far as I understood it is not a problem with the code itself. It's just that the unit of measurement in svg is different from the one used in the normal DOM.

Something like what is done in the DOM to SVG Coordinate Translation section here should be done, using FFI to import getScreenCTM() from Javascript.

I could try to do this

[epost]

Like we discussed just now, for now let's do the transformation on the js side and pull out the translated coordinates through the FFI, instead of exposing getScreenCTM itself.

[epost]

@marcosh related: kwohlfahrt/purescript-halogen-svg#8

[marcosh]

cool, thanks for the pointer. That's almost the same function I wrote

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On Fri, 11 Jan 2019, 19:06 Erik Post ***@***.*** wrote: @marcosh <https://github.com/marcosh> related: kwohlfahrt/purescript-halogen-svg#8 <kwohlfahrt/purescript-halogen-svg#8> — You are receiving this because you were mentioned. Reply to this email directly, view it on GitHub <#90 (comment)>, or mute the thread <https://github.com/notifications/unsubscribe-auth/AChYBNW-sQ0oTkaJXqlx1wbeSIHpO6HEks5vCNKPgaJpZM4Z0u9D> .