Mathematical equations in OPF posts

[Ted Cousins]

Hi, Ted,

Nice. I assume "=FULL" was an attribute of the BBCode IMG tag.

[/quote]
Nope, in XenForo, BBcode allows nothing inserted in the IMG part, says Googlke AI.

I don't remember how "=FULL" got in there

The "full" one reached side-to-side on my screen, regardless of the browser zoomage setting, for zoomages above a certain "step".

 

[Ted Cousins]

Starting over, - with JRuler measuring my screen pixel size:

After opening LibreOffice and messing with the equation editor's font-size and zoom, I cropped and got this image:

Link to original 664px wide:
https://kronometric.org/tmp/MML LibreOffice PNG.png

IMG BBcode here:

Open in FastStone Viewer on my desktop with JRuler on top ... screenshot in BBcode:

Actual original image is 644px wide in spite of how it looks here.

My Windows 11 screen magnification setting is 133%, hence Jruler's "X=494".

Comments invited on this first of several step posts ...

 

[Doug Kerr]

For this test my display "magnification" was set to 125% vs. the usual 150%.

In an OPF post was an image (a gray square) whose width was set numerically to 200 px. In the HTML code here (from the OPF site), style:width was 200 px.

With the zoomage of my browser (Firefox) set to 100%, the onscreen width of that image was essentially 250 px (I did not make a precise measurement.

This along with other recent tests suggests the following:

The onscreen width of an image in an OPF post as seen here, in pixels, is the product of (a) style:width in the HTML code, (b) the current zoomage setting of my browser, and (c) the current "magnification" of my display system.

This is of course what one might expect.

Doug

 

[Doug Kerr]

Hi, Ted,

Starting over, - with JRuler measuring my screen pixel size:

<snip>

Nice exercise.

Here, with the display magnification at 150%, and with the browser zoomage at 100%, your equation picture onscreen is approximately 1000 px wide (I did not attempt a precise measurement)

In the HTML code here there is no style:width attribute for that element, nor are the original image dimensions recited.

We might expect in that case that the browser would render that file at its inherent pixel dimensions (scaled by the browser zoomage and the display magnification).

In this case, that would suggest an onscreen width here of 996 px.

Maybe.

Best regards,

Doug

 

[Ted Cousins]

Hi, Ted,

<snip>

Nice exercise.

Here, with the display magnification at 150%, and with the browser zoomage at 100%, your equation picture onscreen is approximately 1000 px wide (I did not attempt a precise measurement)

In the HTML code here there is no style:width attribute for that element, nor are the original image dimensions recited.

We might expect in that case that the browser would render that file at its inherent pixel dimensions (scaled by the browser zoomage and the display magnification).

In this case, that would suggest an onscreen width here of 996 px.

Maybe.

Best regards,

Doug

Understood, Doug.

Perhaps our aim should be that the equation image size should be the same relative to other elements in the post content area, instead of us continually telling each other FWIW just how big an image looks on our screens ...

 

[Doug Kerr]

Hi, Ted

Perhaps our aim should be that the equation image size should be the same relative to other elements in the post content area, instead of us continually telling each other FWIW just how big an image looks on our screens ...

I have always thought of the matter, as to actual usage, in those terms.

Best regards,

Doug

 

[Ted Cousins]

Hi, Ted

I have always thought of the matter, as to actual usage, in those terms.

Best regards,

Doug

Then we are now on the same page.

Just installed a new screen ruler; AI says that Jruler is old and can be affected by obscure modern Windows stuff.

best,

Ted.

 

[Doug Kerr]

In the course of this inquiry, we have learned many things, and recognized many more things we don't know. I think that is all worthwhile.

But to get back to actual practice, I am hopeful that pictures of equations embedded in OPF posts using various techniques will all serve the intended purpose, in fairly good style, for the various persons that might regard those posts. I have not yet seen examples that clearly show otherwise (assuming "normal" access to the post via the OPF site).

I do note that none of these techniques, involving "pictures" of the equations, will lead to the ideal display outcome for persons that have set their OPF profile to use a display style other then "black on white".

I suspect that for that to work out "nicely" would require the equation, in the HTML code sent to all visitors, to be encoded in MathML.

And I have not yet discovered a way to get that.

Best regards,

Doug

 

[Doug Kerr]

A complication in seeking to reconstruct on the screens of other members the display size of a picture of an equation as compared to the size of the body text is that the body text may not be displayed in the same typeface seen by the originator.

For example, this phrase:

The quick brown fox

is rendered here in the default typeface used by my browser, in the default point size.

This phrase:

The quick brown fox

is rendered here in the default typeface used by my browser, at a explicit point size of 12 points.

This phrase:

The quick brown fox

is rendered here in the Book Antique typeface, which is one of the many typefaces installed in my system, at the explicit point size of 12 points.

If the viewer's system does not include that typeface, one installed there that is considered "similar" will be used to render the phrase.

I do not see this as a problem, given that the exact display size of an included picture of an equation, considered as with respect to the display size of the body test, would rarely be critical.

I think.

Best regards,

Doug

 

[Ted Cousins]

A complication in seeking to reconstruct on the screens of other members the display size of a picture of an equation as compared to the size of the body text is that the body text may not be displayed in the same typeface seen by the originator.

For example, this phrase:

The quick brown fox

is rendered here in the default typeface used by my browser, in the default point size.

This phrase:

The quick brown fox

is rendered here in the default typeface used by my browser, at a explicit point size of 12 points.

This phrase:

The quick brown fox

is rendered here in the Book Antique typeface, which is one of the many typefaces installed in my system, at the explicit point size of 12 points.

If the viewer's system does not include that typeface, one installed there that is considered "similar" will be used to render the phrase.

I do not see this as a problem, given that the exact display size of an included picture of an equation, considered as with respect to the display size of the body test, would rarely be critical.

Glad to hear that, Doug.

best,

Ted.