glPixelZoom — specify the pixel zoom factors
void glPixelZoom( | GLfloat | xfactor, |
GLfloat | yfactor) ; |
glPixelZoom
specifies values for the and zoom factors. During the execution of glDrawPixels or glCopyPixels, if (, ) is the current raster position, and a given element is in the th row and th column of the pixel rectangle, then pixels whose centers are in the rectangle with corners at
(, )
(, )
are candidates for replacement. Any pixel whose center lies on the bottom or left edge of this rectangular region is also modified.
Pixel zoom factors are not limited to positive values. Negative zoom factors reflect the resulting image about the current raster position.
GL_INVALID_OPERATION
is generated if glPixelZoom
is executed between the execution of glBegin and the corresponding execution of glEnd.
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