# OpenGL Translation Tutorial - Help me determine what _ means

This topic is 3588 days old which is more than the 365 day threshold we allow for new replies. Please post a new topic.

## Recommended Posts

I'm reading possibly one of the best tutorials for studying OpenGL here: http://jerome.jouvie.free.fr/OpenGl/Tutorials/Tutorial26.php and under the Translation Transformation area (copy and paste: " How to expressed a vector in the fixed coordinate system ?" to search where I'm at) he uses an underscore to perform some calculation, although I don't know what it represents. I tried looking at the end of the page where he wrote some code, but I can't figure it out. I was hoping someone with experience of doing this might know what it means. He used the period '.' to represent dot-product so I figured the underscore was division or maybe a typo of the substraction sign. -------------------------------------------------------------------------- *EDIT* I think I didn't look hard enough: I found this: //Calculate the formula x = (float)( dx*left.getX() + dy*up.getX() + dz*forward.getX() ); y = (float)( dx*left.getY() + dy*up.getY() + dz*forward.getY() ); z = (float)( dx*left.getZ() + dy*up.getZ() + dz*forward.getZ() );

##### Share on other sites
The underscore doesn't mean a calculation but denotes an index subscription. E.g. V_x means the x component of the vector V. Having the layout mechanisms of HTML at hand, it can be re-written as Vx.

1. 1
Rutin
32
2. 2
3. 3
4. 4
5. 5

• 11
• 13
• 86
• 11
• 10
• ### Forum Statistics

• Total Topics
632972
• Total Posts
3009613
• ### Who's Online (See full list)

There are no registered users currently online

×