I'm studying a text about texture mapping
and in the preparing to draw
session, I read:
Define the texture wrapping parameters. This will control what happens when a texture coordinate greater than 1.0 or less than 0.0 is encountered:
glTexParameteri( GL_TEXTURE_2D, GL_TEXTURE_WRAP_S,wrap);
glTexParameteri( GL_TEXTURE_2D, GL_TEXTURE_WRAP_T,wrap);
where wrap is:
GL_REPEAT : specifies that this pattern will repeat (i.e., wrap-around) if transformed texture coordinates less than 0.0 or greater than 1.0 are encountered.
GL_CLAMP : specifies that the pattern will “stick” to the value at 0.0 or 1.0.
But there's no explanation what is the reason of encountering such texture coordinates?
For example suppose that I have just drawen a rectangle and I want to apply an image as a texture on it, is it possible to encounter such coordinates?