glGetMaterial(3G)glGetMaterial(3G)NAME
glGetMaterial, glGetMaterialfv, glGetMaterialiv - return material
parameters
SYNOPSIS
void glGetMaterialfv(
GLenum face,
GLenum pname,
GLfloat *params ); void glGetMaterialiv(
GLenum face,
GLenum pname,
GLint *params );
PARAMETERS
Specifies which of the two materials is being queried. GL_FRONT or
GL_BACK are accepted, representing the front and back materials,
respectively. Specifies the material parameter to return. GL_AMBIENT,
GL_DIFFUSE, GL_SPECULAR, GL_EMISSION, GL_SHININESS, and
GL_COLOR_INDEXES are accepted. Returns the requested data.
DESCRIPTIONglGetMaterial() returns in params the value or values of parameter
pname of material face. Six parameters are defined: params returns four
integer or floating-point values representing the ambient reflectance
of the material. Integer values, when requested, are linearly mapped
from the internal floating-point representation such that 1.0 maps to
the most positive representable integer value, and -1.0 maps to the
most negative representable integer value. If the internal value is
outside the range [-1, 1], the corresponding integer return value is
undefined. The initial value is (0.2, 0.2, 0.2, 1.0) params returns
four integer or floating-point values representing the diffuse
reflectance of the material. Integer values, when requested, are lin‐
early mapped from the internal floating-point representation such that
1.0 maps to the most positive representable integer value, and -1.0
maps to the most negative representable integer value. If the internal
value is outside the range [-1, 1], the corresponding integer return
value is undefined. The initial value is (0.8, 0.8, 0.8, 1.0). params
returns four integer or floating-point values representing the specular
reflectance of the material. Integer values, when requested, are lin‐
early mapped from the internal floating-point representation such that
1.0 maps to the most positive representable integer value, and -1.0
maps to the most negative representable integer value. If the internal
value is outside the range [-1, 1], the corresponding integer return
value is undefined. The initial value is (0, 0, 0, 1). params returns
four integer or floating-point values representing the emitted light
intensity of the material. Integer values, when requested, are linearly
mapped from the internal floating-point representation such that 1.0
maps to the most positive representable integer value, and -1.0 maps to
the most negative representable integer value. If the internal value is
outside the range [-1, 1.0], the corresponding integer return value is
undefined. The initial value is (0, 0, 0, 1). params returns one inte‐
ger or floating-point value representing the specular exponent of the
material. Integer values, when requested, are computed by rounding the
internal floating-point value to the nearest integer value. The initial
value is 0. params returns three integer or floating-point values rep‐
resenting the ambient, diffuse, and specular indices of the material.
These indices are used only for color index lighting. (All the other
parameters are used only for RGBA lighting.) Integer values, when
requested, are computed by rounding the internal floating-point values
to the nearest integer values.
NOTES
If an error is generated, no change is made to the contents of params.
ERRORS
GL_INVALID_ENUM is generated if face or pname is not an accepted value.
GL_INVALID_OPERATION is generated if glGetMaterial() is executed
between the execution of glBegin() and the corresponding execution of
glEnd().
SEE ALSOglMaterial(3)glGetMaterial(3G)