SFTtech/openage

Pure fixed-point math functions

Open

#1,543 创建于 2023年9月17日

在 GitHub 查看
 (13 评论) (0 反应) (0 负责人)Python (12,130 star) (1,135 fork)batch import
good first issuelang: c++nice new thing ☺

描述

Required Skills: C++

Difficulty: Easy

We should add additional math operations to our fixed-point implementation, so that all calculations can be done purely deterministic. The fpm library already has these operations and could be used as an inspiration.

Important here: These operations must not use any floating point arithmetic for the calculation. They must receive fixed-point values as input and must also return a fixed-point value. This means std library calculations should not be used for solving this issue.

Interesting for us:

  • sqrt
  • min
  • max
  • abs
  • hypot
  • atan2

Nice to have:

  • sin
  • cos
  • tan
  • pow
  • log

Further Reading

贡献者指南

技术栈
cpp
领域
backend
议题类型
feature
难度面向新贡献者的预计实现难度，1 表示很小改动，5 表示专家级工作。
2
预计时间有经验贡献者完成调查、实现、测试并准备 pull request 的粗略时间范围。
1-2 days
活动状态议题当前的可参与程度：新鲜、活跃、陈旧、阻塞或等待维护者输入。
stale
清晰度议题是否清楚说明期望改动、验收标准和下一步。
clear
前置要求
C++fixed point arithmeticfpm library understandingopenage fixed point header
新手友好度1-100 的估计分数，表示该议题对首次贡献者的友好程度。
70
研究方向
Study the existing fixed point.h in libopenage/util. Understand how sqrt, min, max, abs, hypot are implemented (they are already done). Then examine the fpm library's implementation of atan2 and the nice to have functions. Implement the functions ensuring no floating point arithmetic, and add tests and documentation. Pay attention to potential overflow and precision issues.