glScalef as it applies to scaling of a pixel image
A question with regard to glScalef:
I render an image of size X by X, and wish to shrink it down to size Y by Y. I perform glReadPixels to read in the X by X pixels, and command glScalef before using glBegin(GL_POINTS) to redraw the Y by Y image. The red book says that Scalef is based on matrix manipulation, i.e. works on object vertices.
The image looks a little blurred after glScalef has been used on the X by X pixels compared to just rendering a shrunk version of the original model so it comes out as Y by Y pixels in the first place, so something is happening to the pixels due to glScalef.
Does glScalef command the image to be *resampled* from size X by X to Y by Y ??
Does anyone know of any command that enables the Y by Y image to be produced via averaging of the X by X pixels rather than just resampling to achieve the shrink?
Thanks in advance.