Eric Lengyel
@ericlengyel.bsky.social
• Creator of Radical Pie equation editor, Slug Library, C4 Engine
• Math / gamedev author
• Geometric algebra researcher
• Former Naughty Dog, Apple, Sierra
• Math / gamedev author
• Geometric algebra researcher
• Former Naughty Dog, Apple, Sierra
Visual Studio 2026 has a new "Generate preprocessed output for any C++ file" feature that brings us one step closer to parity with the development functionality available in 1995 with CodeWarrior.
November 21, 2025 at 7:16 AM
Visual Studio 2026 has a new "Generate preprocessed output for any C++ file" feature that brings us one step closer to parity with the development functionality available in 1995 with CodeWarrior.
Version 1.1 of the Radical Pie equation editor has been released. This is a free upgrade for all users.
radicalpie.com
radicalpie.com
November 20, 2025 at 2:17 AM
Version 1.1 of the Radical Pie equation editor has been released. This is a free upgrade for all users.
radicalpie.com
radicalpie.com
Projective Geometric Algebra Illuminated has also been remastered with the Radical Pie equation editor in both the soft and hard cover formats. The content is the same, but all 4919 equations appearing in the text plus every equation in every figure has been upgraded with RP.
November 18, 2025 at 10:57 PM
Projective Geometric Algebra Illuminated has also been remastered with the Radical Pie equation editor in both the soft and hard cover formats. The content is the same, but all 4919 equations appearing in the text plus every equation in every figure has been upgraded with RP.
FGED 1&2 have been remastered with the Radical Pie equation editor, and the new versions are now available on Amazon (links below). The content is exactly the same, but the mathematical typesetting got an upgrade. The remaster applies to the soft cover versions only.
November 18, 2025 at 10:47 PM
FGED 1&2 have been remastered with the Radical Pie equation editor, and the new versions are now available on Amazon (links below). The content is exactly the same, but the mathematical typesetting got an upgrade. The remaster applies to the soft cover versions only.
Writing documentation and watching game 7 of the World Series tonight.
November 2, 2025 at 2:07 AM
Writing documentation and watching game 7 of the World Series tonight.
New blog post about the development of Radical Pie:
terathon.com/blog/radical...
terathon.com/blog/radical...
November 1, 2025 at 10:32 PM
New blog post about the development of Radical Pie:
terathon.com/blog/radical...
terathon.com/blog/radical...
About two months from now, I'll be showing Radical Pie at the Joint Mathematics Meetings in Washington, D.C. I already have the best booth location on the exhibit floor.
jointmathematicsmeetings.org/jmm
jointmathematicsmeetings.org/jmm
October 29, 2025 at 10:38 PM
About two months from now, I'll be showing Radical Pie at the Joint Mathematics Meetings in Washington, D.C. I already have the best booth location on the exhibit floor.
jointmathematicsmeetings.org/jmm
jointmathematicsmeetings.org/jmm
With a couple quick color changes, Radical Pie runs in dark mode.
October 29, 2025 at 8:33 PM
With a couple quick color changes, Radical Pie runs in dark mode.
I am excited to announce the release of Radical Pie, version 1.0! This is the professional equation typesetting application that I've been working on for the last year. See the website for details.
radicalpie.com
radicalpie.com
October 28, 2025 at 10:39 PM
I am excited to announce the release of Radical Pie, version 1.0! This is the professional equation typesetting application that I've been working on for the last year. See the website for details.
radicalpie.com
radicalpie.com
Radical Pie has a gazillion typesetting parameters that you can fine-tune to your heart's content. Here's all the stuff you can tweak for parentheses, brackets, braces, etc.
October 24, 2025 at 3:53 AM
Radical Pie has a gazillion typesetting parameters that you can fine-tune to your heart's content. Here's all the stuff you can tweak for parentheses, brackets, braces, etc.
When I wrote PGA Illuminated, I had to paste an equation in Illustrator to draw highlights and annotations like these. Not any more. With Radical Pie, they get drawn directly in the equation editor, they auto-resize during edits, and everything stays live when embedding in Word.
October 21, 2025 at 11:23 PM
When I wrote PGA Illuminated, I had to paste an equation in Illustrator to draw highlights and annotations like these. Not any more. With Radical Pie, they get drawn directly in the equation editor, they auto-resize during edits, and everything stays live when embedding in Word.
The Radical Pie editor has 16 palettes across the top containing just over 600 common symbols and mathematical structures. (The entirety of Unicode can be accessed through a separate dialog.) radicalpie.com
October 20, 2025 at 9:35 PM
The Radical Pie editor has 16 palettes across the top containing just over 600 common symbols and mathematical structures. (The entirety of Unicode can be accessed through a separate dialog.) radicalpie.com
Radical Pie has a large number of user-configurable parameters that control precise spacing, positioning, sizing, and various shapes (like arrowheads) in an equation. The final count is 335, and they can all be set in 23 different panels shown in a couple big dialog boxes.
October 19, 2025 at 10:23 PM
Radical Pie has a large number of user-configurable parameters that control precise spacing, positioning, sizing, and various shapes (like arrowheads) in an equation. The final count is 335, and they can all be set in 23 different panels shown in a couple big dialog boxes.
Some people are particular about how much their integrals lean forward. Radical Pie is going to let you choose whatever angle you want, and it will generate the corresponding Bézier curves. These examples range from −2.5° to 15° right of vertical through the center.
October 7, 2025 at 11:05 PM
Some people are particular about how much their integrals lean forward. Radical Pie is going to let you choose whatever angle you want, and it will generate the corresponding Bézier curves. These examples range from −2.5° to 15° right of vertical through the center.
I'm getting valuable feedback from the Radical Pie beta test. Some minor bugs have been discovered. No major issues. It's looking good!
October 4, 2025 at 10:34 PM
I'm getting valuable feedback from the Radical Pie beta test. Some minor bugs have been discovered. No major issues. It's looking good!