gluScaleImage
[New
- Windows 95, OEM Service Release 2]
The gluScaleImage function scales an image to
an arbitrary size.
int gluScaleImage(
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GLenum format, |
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GLint widthin, |
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GLint heightin, |
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GLenum typein,
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const void * datain, |
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GLint widthout,
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GLint heightout,
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GLenum typeout, |
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void * dataout |
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Parameters
format
The format of
the pixel data. The following symbolic values are valid: GL_COLOR_INDEX,
GL_STENCIL_INDEX, GL_DEPTH_COMPONENT, GL_RED, GL_GREEN, GL_BLUE, GL_ALPHA,
GL_RGB, GL_RGBA, GL_BGR_EXT, GL_BGRA_EXT, GL_LUMINANCE, and GL_LUMINANCE_ALPHA.
widthin,
heightin
The width and
height, respectively, of the source image that is scaled.
typein
The data type
for datain. Must be one of the following: GL_UNSIGNED_BYTE, GL_BYTE,
GL_BITMAP, GL_UNSIGNED_SHORT, GL_SHORT, GL_UNSIGNED_INT, GL_INT, or GL_FLOAT.
datain
A pointer to
the source image.
widthout,
heightout
The width and
height, respectively, of the destination image.
typeout
The data type
for dataout. Must be one of the following: GL_UNSIGNED_BYTE, GL_BYTE,
GL_BITMAP, GL_UNSIGNED_SHORT, GL_SHORT, GL_UNSIGNED_INT, GL_INT, or GL_FLOAT.
dataout
A pointer to
the destination image.
Return Values
If the function succeeds, the return value is zero.
If the function fails, the return value is a GLU error
code (see gluErrorString).
Remarks
The gluScaleImage function scales a pixel image
using the appropriate pixel store modes to unpack data from the source image
and pack data into the destination image.
When shrinking an image, gluScaleImage uses a
box filter to sample the source image and create pixels for the destination
image. When magnifying an image, the pixels from the source image are linearly
interpolated to create the destination image.
For a description of the acceptable values for the format,
typein, and typeout parameters, see glReadPixels.
See Also