1GLGETMATERIAL(3G) GLGETMATERIAL(3G)
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6 glGetMaterialfv, glGetMaterialiv - return material parameters
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10 void glGetMaterialfv( GLenum face,
11 GLenum pname,
12 GLfloat *params )
13 void glGetMaterialiv( GLenum face,
14 GLenum pname,
15 GLint *params )
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19 face Specifies which of the two materials is being queried.
20 GL_FRONT or GL_BACK are accepted, representing the front and
21 back materials, respectively.
22 pname Specifies the material parameter to return. GL_AMBIENT,
24 GL_DIFFUSE, GL_SPECULAR, GL_EMISSION, GL_SHININESS, and
25 GL_COLOR_INDEXES are accepted.
26 params Returns the requested data.
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30 glGetMaterial returns in params the value or values of parameter pname
31 of material face. Six parameters are defined:
32 GL_AMBIENT params returns four integer or floating-point
34 values representing the ambient reflectance of
35 the material. Integer values, when requested,
36 are linearly mapped from the internal floating-
37 point representation such that 1.0 maps to the
38 most positive representable integer value, and
39 -1.0 maps to the most negative representable
40 integer value. If the internal value is outside
41 the range [-1, 1], the corresponding integer
42 return value is undefined. The initial value is
43 (0.2, 0.2, 0.2, 1.0)
44 GL_DIFFUSE params returns four integer or floating-point
46 values representing the diffuse reflectance of
47 the material. Integer values, when requested,
48 are linearly mapped from the internal floating-
49 point representation such that 1.0 maps to the
50 most positive representable integer value, and
51 -1.0 maps to the most negative representable
52 integer value. If the internal value is outside
53 the range [-1, 1], the corresponding integer
54 return value is undefined. The initial value is
55 (0.8, 0.8, 0.8, 1.0).
56 GL_SPECULAR params returns four integer or floating-point
58 values representing the specular reflectance of
59 the material. Integer values, when requested,
60 are linearly mapped from the internal floating-
61 point representation such that 1.0 maps to the
62 most positive representable integer value, and
63 -1.0 maps to the most negative representable
64 integer value. If the internal value is outside
65 the range [-1, 1], the corresponding integer
66 return value is undefined. The initial value is
67 (0, 0, 0, 1).
68 GL_EMISSION params returns four integer or floating-point
70 values representing the emitted light intensity
71 of the material. Integer values, when requested,
72 are linearly mapped from the internal floating-
73 point representation such that 1.0 maps to the
74 most positive representable integer value, and
75 -1.0 maps to the most negative representable
76 integer value. If the internal value is outside
77 the range [-1, 1.0], the corresponding integer
78 return value is undefined. The initial value is
79 (0, 0, 0, 1).
80 GL_SHININESS params returns one integer or floating-point
82 value representing the specular exponent of the
83 material. Integer values, when requested, are
84 computed by rounding the internal floating-point
85 value to the nearest integer value. The initial
86 value is 0.
87 GL_COLOR_INDEXES params returns three integer or floating-point
89 values representing the ambient, diffuse, and
90 specular indices of the material. These indices
91 are used only for color index lighting. (All the
92 other parameters are used only for RGBA light‐
93 ing.) Integer values, when requested, are com‐
94 puted by rounding the internal floating-point
95 values to the nearest integer values.
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98 If an error is generated, no change is made to the contents of params.
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101 GL_INVALID_ENUM is generated if face or pname is not an accepted value.
102 GL_INVALID_OPERATION is generated if glGetMaterial is executed between
104 the execution of glBegin and the corresponding execution of glEnd.
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107 glMaterial(3G)
108 GLGETMATERIAL(3G)