//Legacy code i've written that may still be useful for ideas

Links I've found.

Algorithms:
http://www-cs-students.stanford.edu/~amitp/gameprog.html (algorithms. A* tilemap, etc...)
paulbourke.net/geometry/polygonise/ (if ever want to try out marching cubes)
https://blackpawn.com/texts/pointinpoly/ (fast point in triangle test using barycentric coordinates)

PDF Online books:
Procedural Content Generation in games... http://pcgbook.com/
Game Programming Patterns
https://craftinginterpreters.com/ (by same as gameprogrammingpatterns.com)
natureofcode.com

3d graphics
arcsynthesis tutorials https://www.roiatalla.com/public/arcsynthesis/html/index.html (someone saved them)
https://www.scratchapixel.com/

Differential Equations
https://tutorial.math.lamar.edu/Classes/DE/DE.aspx

win32
//was a relisoft/win32/index.html back in the day had bookmarked but gone now