In the methods of two part texture mapping and environment mapping

a sphere is usually used as the intermediary surface

where a kind of sphere mapping algorithm is contained as their important component. Furthermore

the algorithm of sphere mapping may also be applied in recognition of surfaces and generation of landscapes

etc. In order to decrease the texture distortion caused by the algorithm of sphere mapping

the paper discusses the traditional algorithms of sphere mapping and its shortcomings at first according to the non|distortion criterions of sphere texture mapping. And then

a new algorithm of texture mapping is put forward

which is applicable to partial area of a sphere. Because the ratio of areas between a texture region on the texture plane and the corresponding mapping region on the partial sphere is used as a constraint

the quality of texture mapping is obviously improved. Finally

some of the experimental results are presented

which show that the new algorithm is quite effective and has certain advantage compared to the traditional algorithms of sphere mapping.