[QUOTE=Alfonse Reinheart;1264930]I will say this: neither the OpenGL Wiki search nor Google were terribly useful in finding the answer. Oh sure, I know that the answer was in the fourth result in Google when searching for “OpenGL Interpolation”. But I only knew that because I knew what I was looking for already.
However, I just fixed the OpenGL Wiki to be more helpful in this question. Searching for “Interpolation” takes you to a disambiguation page, the first version of which links you directly to what you need to know.
Namely, that interpolation is not controlled by an “api function” but by shaders. That’s why you couldn’t find it; you were looking in the wrong place.
That being said, this thread was absolutely terrible from the first post. That post made it very difficult to determine what you were asking for. You said something about “color render function”, which doesn’t make any sense. Furthermore, the code you posted was sufficiently broken that nobody could tell what you were looking for without you further clarifying it.
Indeed, it took until the 7th post that it became marginally clear what you were looking for. In response to something you said in post #8, no, it is not clear that interpolation was happening, because you failed to explain what was going on or what you were interested in discovering.
In the future, please spend more time formulating your question so that it’s at least clear what information you’re looking for. If you’re not going to actually follow any of the tutorials that would explain all this stuff to you (note: there’s a difference between actually following a tutorial and just scanning through it for an answer to your current problem. Don’t use tutorials for the latter), then you could at least try to ask a whole and complete question that clearly explains what your problem is.[/QUOTE]
Questing is a kind of art, one can make it sense of it, one not, which has to be guessed by ansewers. after exchange times, they could understand each other.
I may not make it clearly at all, What I want to know is in this program, which statement described the roit of colors in the triangle? or which math formula in it describe the interpolation?
Is the interpolation processed in this example by linear or exponent? or other way of curves?
for examle, we draw a point by POINT()… what is it in the triangle to present the color?