3 ms·

> if font rendering could be improved by using a Lanczos filter instead of a box filter You don't want an ideal filter for rendering fonts -- you want sharp ed

by vardump 10y ago

> if font rendering could be improved by using a Lanczos filter instead of a box filter You don't want an ideal filter for rendering fonts -- you want sharp edges instead. A lot of work [1][2] has been done to achieve this. In font rendering, alignment to pixel boundaries is intentional, it's called hinting. So you could say aliasing is used for an advantage. [1]: https://en.wikipedia.org/wiki/Font_hinting https://en.wikipedia.org/wiki/Font_hinting [2]: https://en.wikipedia.org/wiki/Subpixel_rendering https://en.wikipedia.org/wiki/Subpixel_rendering

Ericson2314 10y ago
I think on today's high density mobile phone screens, these techniques are no longer needed.
- wtallis 10y ago
  They can still provide some benefit, but it's true that modern high-DPI mobile screens don't need the heavy-handed hinting of Windows and doing subpixel rendering when the subpixel orientation keeps changing as the device is rotated can be more trouble than it's worth.
- TheRealPomax 10y ago
  if those were the only screens in the world, I would agree wholeheartedly, but there are millions, if not more, non-mobile screens in use today. This problem is unlike to go away with high-dpi technology in the next 20 maybe even 50 years.
  - Ericson2314 10y ago
    Well, a different render can be written for those screens. I assume 4K will come do predominate, but we'll see.
Mathnerd314 10y ago
> you want sharp edges instead It depends on your philosophy: https://blog.codinghorror.com/font-rendering-respecting-the-pixel-grid/ https://blog.codinghorror.com/font-rendering-respecting-the-... http://www.joelonsoftware.com/items/2007/06/12.html http://www.joelonsoftware.com/items/2007/06/12.html In general antialiasing and font hinting are at odds; you want one but not the other. With recent displays, the pixels are small enough that you can use anti-aliasing all the time, and no hinting: http://lh5.ggpht.com/-tsgwX-9fsRc/U6armqjI6QI/AAAAAAAAB9E/Bw_maJHnDIc/s1600-h/ppi-size-2%25255B9%25255D.png http://lh5.ggpht.com/-tsgwX-9fsRc/U6armqjI6QI/AAAAAAAAB9E/Bw... Subpixel rendering is just another anti-aliasing technique; it can be used on any bitmap. Of course, it's also true that the sinc filter is not the best possible. There's interesting research on shearlet transformations http://colorlab.no/content/download/46570/721686/file/2014_CIC22_PEDERSEN_PG37.pdf http://colorlab.no/content/download/46570/721686/file/2014_C... and other weird filters http://www.ansatt.hig.no/mariusp/publications/Pedersen2015_ICIP.pdf http://www.ansatt.hig.no/mariusp/publications/Pedersen2015_I.... Or just avoid the filtering stuff entirely and optimize a whole-eye model: http://michaelfrankdeering.com/blog/projects/eye_work/eye_model/ http://michaelfrankdeering.com/blog/projects/eye_work/eye_mo...

by vardump 10y ago

Ericson2314 10y ago

I think on today's high density mobile phone screens, these techniques are no longer needed.

wtallis 10y ago
They can still provide some benefit, but it's true that modern high-DPI mobile screens don't need the heavy-handed hinting of Windows and doing subpixel rendering when the subpixel orientation keeps changing as the device is rotated can be more trouble than it's worth.
TheRealPomax 10y ago
if those were the only screens in the world, I would agree wholeheartedly, but there are millions, if not more, non-mobile screens in use today. This problem is unlike to go away with high-dpi technology in the next 20 maybe even 50 years.
- Ericson2314 10y ago
  Well, a different render can be written for those screens. I assume 4K will come do predominate, but we'll see.

Mathnerd314 10y ago

> you want sharp edges instead It depends on your philosophy: https://blog.codinghorror.com/font-rendering-respecting-the-pixel-grid/ https://blog.codinghorror.com/font-rendering-respecting-the-... http://www.joelonsoftware.com/items/2007/06/12.html http://www.joelonsoftware.com/items/2007/06/12.html In general antialiasing and font hinting are at odds; you want one but not the other. With recent displays, the pixels are small enough that you can use anti-aliasing all the time, and no hinting: http://lh5.ggpht.com/-tsgwX-9fsRc/U6armqjI6QI/AAAAAAAAB9E/Bw_maJHnDIc/s1600-h/ppi-size-2%25255B9%25255D.png http://lh5.ggpht.com/-tsgwX-9fsRc/U6armqjI6QI/AAAAAAAAB9E/Bw... Subpixel rendering is just another anti-aliasing technique; it can be used on any bitmap. Of course, it's also true that the sinc filter is not the best possible. There's interesting research on shearlet transformations http://colorlab.no/content/download/46570/721686/file/2014_CIC22_PEDERSEN_PG37.pdf http://colorlab.no/content/download/46570/721686/file/2014_C... and other weird filters http://www.ansatt.hig.no/mariusp/publications/Pedersen2015_ICIP.pdf http://www.ansatt.hig.no/mariusp/publications/Pedersen2015_I.... Or just avoid the filtering stuff entirely and optimize a whole-eye model: http://michaelfrankdeering.com/blog/projects/eye_work/eye_model/ http://michaelfrankdeering.com/blog/projects/eye_work/eye_mo...