To provide a rendering program, a rendering apparatus, and a rendering method, which are capable of displaying a sterical model surface using a fabric in which the real feel of material is reproduced. A reflection property measurement device 10 receives reflected light of an actual yarn T2 and measures a reflection property representing the energy of the reflected light of the yarn T2. A correction portion 106 calculates a specular reflection coefficient Ks, a glossiness coefficient p, and first and second diffuse reflection coefficients Kd1, Kd2 by using parameter fitting so that the error between the reflection property of the actual yarn and the energy of the reflected light obtained from a reflection function becomes minimum. A rendering portion 107 renders the sterical model by using the reflection function in which the coefficients are calculated and a texture which is the model of a fabric subjected to a napping treatment.