---

Manual Reference Pages  - GLGETMATERIAL (3G)

---

glGetMaterialfv, glGetMaterialiv - return material parameters

CONTENTS

C Specification
Parameters
Description
Notes
Errors
See Also

void glGetMaterialfv( GLenum face,

                    GLenum pname,
                    GLfloat *params )

void glGetMaterialiv( GLenum face,

                    GLenum pname,
                    GLint *params )

face	Specifies which of the two materials is being queried.  GL_FRONT or  GL_BACK are accepted, representing the front and back materials, respectively.
pname	Specifies the material parameter to return.  GL_AMBIENT,  GL_DIFFUSE,  GL_SPECULAR,  GL_EMISSION,  GL_SHININESS, and  GL_COLOR_INDEXES are accepted.
params	Returns the requested data.

 glGetMaterial returns in params the value or values of parameter pname of material face. Six parameters are defined:

GL_AMBIENT	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)
GL_DIFFUSE	params returns four integer or floating-point values representing the diffuse 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 (0.8, 0.8, 0.8, 1.0).
GL_SPECULAR	params returns four integer or floating-point values representing the specular 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, 0, 0, 1).
GL_EMISSION	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).
GL_SHININESS	params returns one integer 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.
GL_COLOR_INDEXES	params returns three integer or floating-point values representing 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.

If an error is generated, no change is made to the contents of params.

 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.

 glMaterial(3G)

Jump to page    or go to Top of page |  Section 3G |  Main Index.