1	CS425 OpenGL Materials
2	What Color Is It?
3	What Color Is It?
4	What Color Is It?
5	What Color Is It?
6	What Color Is It?
7	What Color Is It?
8	What Color Is It?
9	Material Response to Light The material specified in OpenGL can have three different responses to the light hitting it plus one emissive characteristic. You can separately specify the response to: Ambient Diffuse Specular And you can specify that the material “emits light”
10	glMaterial{if}v(face, pname, param) face GL_FRONT GL_BACK GL_FRONT_AND_BACK
11	glMaterial{if}v(face, pname, param) pname GL_AMBIENT (ambient color of material) GL_DIFFUSE (diffuse color of material) GL_AMBIENT_AND_DIFFUSE (both) GL_SPECULAR (specular color of material) GL_SHININESS (specular exponent) GL_EMISSION (emissive color of material) GL_COLOR_INDEXES (ambient, diffuse, and specular color indices)
12	glMaterial{if}v(face, pname, param ) param The value for the pname’d material property Example GLfloat mat_amb_diff [ ] = {0.1, 0.5, 0.8, 1.0}; glMaterialfv( GL_FRONT_AND_BACK, GL_AMBIENT_AND_DIFFUSE, mat_amb_diff);
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14	Nate Robbins Lightmaterial
15	Color Material Mode I didn’t find this previously. Causes the material property specified to track the value of the current color (glColor*) glColorMaterial(face, mode) “face” and “mode” are same as for glMaterial. Must use glEnable (see example)
16	glColorMaterial example
17	colormat.c
18	Two Sided Materials
19	Additional Clipping Plane
20	Two Sided Materials with Cutting Plane
21	OpenGL Attenuation Same formula that Denbigh gave.
22	Function Calls You use the glLightf function to select attenuation factors. Default values are kc=1, kl=0, kq=0. glLightf(GL_LIGHT0, GL_CONSTANT_ATTENUATION, 2.0); glLightf(GL_LIGHT0, GL_LINEAR_ATTENUATION, 0.0); glLlightf(GL_LIGHT0, GL_QUADRATIC_ATTENUATION, 0.0);
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