1. A method of rendering image data in a rendering system, comprising: determining an order of rendering a plurality of surfaces for forming a resultant image based on a distance between a rendering viewpoint, different from an original viewpoint, and a surface, of the plurality of surfaces, by referring to three-dimensional space data for the image data; selectively, using at least one processing device, performing a blending on a splat of the surface in a same path as a generating of the depth information values for a plurality of splats included in the surface, in the order of rendering, based on an offset with respect to a range for the blending of the splat, the offset being surface depth information; and generating splat information values in the same path as the performing of the blending of the splat.