Take the 2-minute tour ×
Game Development Stack Exchange is a question and answer site for professional and independent game developers. It's 100% free, no registration required.

I know that what both glEdgeFlagv and glEdgeFlag do is toggle boundary edge status, but my question is why does the v version exist when the documentation specifies that the only difference is that glEdgeFlagv takes (quoting from documentation):

a pointer to an array that contains a single Boolean element, which replaces the current edge flag value.

What's the point of having a special version that takes a pointer to an array of length one? I can't imagine its to let you toggle the pointed-to bool to change the value later because the documentation would have to mention that to avoid inadvertent frees. I don't know of any platform where a pointer is smaller than a bool. When would one use glEdgeFlagv instead of glEdgeFlag?

share|improve this question
add comment

2 Answers

up vote 3 down vote accepted

It is there for the sake of completeness and consistency with the other APIs. There are vector forms of glVertex, glColor, glTexCoord, etc. glEdgeFlag is part of that group of functions; therefore, there is a vector version of glEdgeFlag.

share|improve this answer
add comment

If you are looking for just the outline portion of the graphic, you could try using an emboss filter on it. The outline will be highlighted in white and remove the other non-white pixels below a certain tolerance.

Here's a decent link talking about various image filters and matrices for accomplishing them: Image Processing for Dummies with C# and GDI+ Part 2 - Convolution Filters

share|improve this answer
    
This doesn't seem to answer the question. –  Tetrad Aug 11 '11 at 16:21
add comment

Your Answer

 
discard

By posting your answer, you agree to the privacy policy and terms of service.

Not the answer you're looking for? Browse other questions tagged or ask your own question.