In an online bookstore, the mathematical symbols are not displayed correctly in a certain font when displaying the reading sample of a certain book. Instead of an equal sign, for example, the Unicode character 𝕴 U+1D574 is displayed. And that's just one character out of many that is not displayed correctly. The error occurs on both Firefox and Chromium.
At first I thought it might be the website, but that doesn't seem to be the case. Because when I view the sample of the book in a VM on a Debian Live CD, in Linux Mint Debian Edition, Ubuntu 24.04 Beta or Windows 10, the mathematical symbols are all displayed correctly. The problem only seems to occur on my Debian installation. Which is Debian 12.5 (stable). The initial installation was with Debian 10 stable and was then upgraded to Debian 11 and later to Debian 12.I only use packages from the official Debian package repository. And apart from the Intel microcode and the NVIDIA drivers, nothing proprietary is installed.
Now I would like to know why that is. While a fresh Debian Live CD hardly installed anything, I of course installed a lot of other packages from the Debian repository. What's also strange is that the affected font could be a font embedded in the document. In this case, I'm surprised that the formulas are displayed correctly in a fresh Debian installation. Because if the font is embedded in the data, then it should also be displayed incorrectly in the Debian Live CD, but that is not the case.
Steps to reproduce (if you are affected):
1. Open the following link, it is showing the page of the book "Real-time Rendering" ISBN 978-1-138-62700-0
https://www.thalia.de/shop/home/artikel ... 1049479583
2. Make sure that JavaScript is enabled in your browser, then click below the book's front cover picture on the word "Leseprobe" (in English this can be translated to "Read sample").
3. This will open the reading sample of the book. The book itself is in English.
4. Now go to chapter "1.2.1 Mathematical Notation" and look at the representation of a vector.
On my system I see the following on Firefox and Chromium:
But the following should be shown:
Yes, bracketing is missing for the vector in the document, but this is missing not only on my system, but also in the VM with the guest systems of a Debian Live CD, Windows 10 and the other systems mentioned above where the other characters are displayed correctly. The brackets are displayed in the reading sample on Amazon. The same applies to the square bracket for displaying the matrix.
Since this is just one example of many, it gets even worse a few pages later in the book. Instead of mathematical symbols, completely different symbols are displayed. In the matrix display under formula (1.1), the infinity symbol is displayed instead of subscript digits for numbering for each entry.
The font in use can be changed in this reading sample view by pressing on the font button labeled with AA in the upper right corner and there you can change the selected font in the key value pair labeled with "Schriftart". If i change the selected fonts from "Verlagsschrift" to something else, for example "Ubuntu" then everything is shown correctly.
At first I thought it might be the website, but that doesn't seem to be the case. Because when I view the sample of the book in a VM on a Debian Live CD, in Linux Mint Debian Edition, Ubuntu 24.04 Beta or Windows 10, the mathematical symbols are all displayed correctly. The problem only seems to occur on my Debian installation. Which is Debian 12.5 (stable). The initial installation was with Debian 10 stable and was then upgraded to Debian 11 and later to Debian 12.
Code:
$ inxi -SSystem: Host: ########### Kernel: 6.1.0-20-amd64 arch: x86_64 bits: 64 Desktop: KDE Plasma v: 5.27.5 Distro: Debian GNU/Linux 12 (bookworm)Now I would like to know why that is. While a fresh Debian Live CD hardly installed anything, I of course installed a lot of other packages from the Debian repository. What's also strange is that the affected font could be a font embedded in the document. In this case, I'm surprised that the formulas are displayed correctly in a fresh Debian installation. Because if the font is embedded in the data, then it should also be displayed incorrectly in the Debian Live CD, but that is not the case.
Steps to reproduce (if you are affected):
1. Open the following link, it is showing the page of the book "Real-time Rendering" ISBN 978-1-138-62700-0
https://www.thalia.de/shop/home/artikel ... 1049479583
2. Make sure that JavaScript is enabled in your browser, then click below the book's front cover picture on the word "Leseprobe" (in English this can be translated to "Read sample").
3. This will open the reading sample of the book. The book itself is in English.
4. Now go to chapter "1.2.1 Mathematical Notation" and look at the representation of a vector.
On my system I see the following on Firefox and Chromium:
vxv 𝕴 vy⇔ vzBut the following should be shown:
vxv = vy, vzYes, bracketing is missing for the vector in the document, but this is missing not only on my system, but also in the VM with the guest systems of a Debian Live CD, Windows 10 and the other systems mentioned above where the other characters are displayed correctly. The brackets are displayed in the reading sample on Amazon. The same applies to the square bracket for displaying the matrix.
Since this is just one example of many, it gets even worse a few pages later in the book. Instead of mathematical symbols, completely different symbols are displayed. In the matrix display under formula (1.1), the infinity symbol is displayed instead of subscript digits for numbering for each entry.
The font in use can be changed in this reading sample view by pressing on the font button labeled with AA in the upper right corner and there you can change the selected font in the key value pair labeled with "Schriftart". If i change the selected fonts from "Verlagsschrift" to something else, for example "Ubuntu" then everything is shown correctly.
Statistics: Posted by Borg — 2024-04-15 10:42 — Replies 0 — Views 91