Why does OpenGL use degrees instead of radians?

Question

The OpenGL designers were never afraid of mathematics, and knowledge of linear algebra is essential for all but the simplest OpenGL applications. I think it can safely be assumed that OpenGL programmers are familiar with angles in radians.

Mathematically, radians are more elegant than degrees in every respect. They also have practical advantages:

• The C standard library uses radians.
• Pretty much any other library out there uses radians as well.
• Radians are more convenient in some computations, e.g. the length of a circular arc.

Why, then, did the OpenGL designers decide to specify functions like glRotatef and gluPerspective to use degrees?

(I know it's of no practical importance, and it's not going to change anyway. I'm just curious, and I couldn't find the answer on OpenGL.org.)

Answer 1

2 가지 방법이 있습니다.

첨부 파일 목록에 숨겨진 필드를 생성하고 이벤트 수신자의 도움으로 첨부 파일이 추가 된 경우 삭제되면 설정합니다.이제 첨부 파일 이름이 있습니다 (필요한 경우 링크로 추가하십시오.이 열은 멀티 행 텍스트 상자 (서식있는 텍스트 필드 유형) 여야합니다.

두 번째 및 쉬운 방법은 SharePoint Designer를 사용하는 수정입니다."nofollow"> http : // amitphule을 참조하십시오.blogspot.in/2012/04/display-item-tatchment-in-sharepoint.html

추가 도움이 필요하면 알려주십시오.

Answer 2

I'd say that since OpenGL was designed with the end-user in mind, degrees were used because one can specify important angles (90, 180, 270 ...) with integers only, and so there is no need for a floating point GL_PI constant.

Answer 3

I think it is because you should be able to get an exact rotation matrix for certain angles like 90 or 180 degrees. Like other people here has specified, if you use pi/2 instead of 90 degrees, rounding errors may lead to a transformation matrix that almost performs a rotation by 90 degrees.

Answer 4

Code is easier to read, it eases learning curve for newbies and allows quick hacking.

As stated already - degrees HAVE advantage - humans are better used to degrees, compare: 0.78539816339744830961566084581988... to 45 degrees for example :/.

For advanced uses of OpenGL you provide your own matrices anyway.

Answer 5

Well, what happens in most cases is that you use a Math library to convert from radians to degrees and back to radians. I agree with most of what was said by the previous awesome posters.

It's more human readable.